Skip to Content

Yellow Fever Vaccine

Class: Vaccines
ATC Class: J07B101
VA Class: IM100
Brands: YF-VAX

Introduction

Live, attenuated virus vaccine.100 106 115 106 Available in US as vaccine prepared using the 17D-204 strain of yellow fever virus;100 106 available in other countries as vaccines prepared using either the 17D-204 or 17DD strain.100 106 115

Uses for Yellow Fever Vaccine

Prevention of Disease Caused by Yellow Fever Virus

Prevention of disease caused by yellow fever virus in adults, adolescents, and children ≥9 months of age residing or traveling in areas of Africa or South America where yellow fever is endemic or officially reported or where an International Certificate of Vaccination or Prophylaxis (ICVP) against yellow fever is required as a condition for entry.106 115

Prevention of disease caused by yellow fever virus in laboratory personnel who might be exposed by direct or indirect contact or by aerosols to virulent yellow fever virus or to concentrated preparations of the yellow fever vaccine strain.100 106

Yellow fever virus, a Flavivirus100 105 106 115 closely related to Dengue, Japanese encephalitis virus, St. Louis encephalitis viruses, and West Nile virus (WNV),100 105 is transmitted to humans through the bite of infected mosquitoes that acquired the virus by biting infected humans or nonhuman primates (monkeys).100 101 106 115

Disease caused by yellow fever virus ranges from mild, nonspecific febrile illness to severe disease with jaundice, hemorrhagic symptoms, and eventually shock and multisystem organ failure;100 104 115 case fatality rate for severe disease is 20–50%.100 104 WHO estimates that about 200,000 cases of yellow fever and 30,000 fatalities related to the disease occur annually worldwide.100 101

Travelers to areas of sub-Saharan Africa and tropical South America where yellow fever virus is endemic and intermittently epidemic are at high risk of disease caused by yellow fever virus.100 101 104 115 Risk depends on several factors, including vaccination status, use of personal protective measures against mosquito bites, travel locations, season, duration of exposure, occupational and recreational activities while traveling, and local rate of yellow fever virus transmission at the time of travel.100 101 104 115

For US travelers, the US Public Health Service Advisory Committee on Immunization Practices (ACIP) and CDC recommend primary immunization with yellow fever vaccine in adults, adolescents, and children ≥9 months of age who will be traveling to or living in yellow fever endemic or epidemic areas of Africa and South America.100 115 However, because serious adverse effects have been reported with yellow fever vaccine (see Cautions), base vaccination decisions on careful consideration of the individual's overall risk for travel-associated yellow fever, the high mortality rate reported for yellow fever, international regulations regarding yellow fever vaccination for countries on the travel itinerary, and all known precautions and contraindications for the vaccine.100 115

ACIP states that primary immunization with a single dose of yellow fever vaccine provides long-lasting protection and is adequate for most travelers, but revaccination is recommended for certain travelers who will be visiting countries with a risk of yellow fever virus transmission (e.g., women who received primary immunization during pregnancy, individuals who received a hematopoietic stem cell transplant after receiving primary immunization, individuals who had HIV infection when they received their last dose of yellow fever vaccine).104 ACIP also states revaccination (booster dose) may be given to travelers who received their last dose of yellow fever vaccine at least 10 years previously and who will be in higher-risk settings based on location, season, activities, and duration of travel.104 This includes travelers who plan to spend prolonged periods in endemic areas or those traveling to highly endemic areas (e.g., rural West Africa during peak transmission season) or to areas with an ongoing outbreak of yellow fever.104

International health regulations (IHR) of the World Health Organization (WHO) allow countries to require proof of yellow fever vaccination documented on a validated ICVP as a condition of entry for travelers arriving from infected areas or from countries with infected areas, even if only in transit.100 115 Some countries require evidence of yellow fever vaccination from all entering travelers, including those traveling directly from the US.100 115 Travelers who have a specific contraindication to yellow fever vaccine and who cannot avoid travel to a country requiring vaccination should obtain a medical waiver before embarking on travel (see Medical Waivers under Cautions).100 115 Requirements regarding ICVPs may be strictly enforced and travelers arriving without a valid ICVP or medical waiver may be quarantined for up to 6 days, denied entry, or possibly vaccinated or revaccinated at the point of entry.100 115

Vaccinees should receive a completed yellow fever vaccine ICVP that is signed and validated with the official uniform stamp of the yellow fever vaccination center where the vaccine was given.100 106 115 These certificates are valid for 10 years beginning 10 days after vaccination with yellow fever vaccine.100 106 115 As of July 2016, WHO no longer requires revaccination (booster dose) of yellow fever vaccine every 10 years and states that a completed ICVP is considered valid for the lifetime of the vaccinee.115 However, it is uncertain when or if all countries with entry requirements for yellow fever vaccination will adopt this change.115

In addition to vaccination, individuals traveling to areas with yellow fever should take precautions to avoid exposure to mosquitoes (e.g., stay in air-conditioned or well-screened quarters, wear long-sleeved shirts and long pants to cover the body, use appropriate insect repellents, use mosquito nets between dusk and dawn).115 Although yellow fever transmission is unusual in urban areas and only occurs during an epidemic, travelers to rural areas of South America and Africa may be exposed to mosquitoes transmitting the disease and other mosquito-borne diseases.115

The most recent information regarding geographic areas associated with risk of yellow fever, information on country-specific requirements for yellow fever vaccination for travelers, and information on regulations regarding ICVPs and medical waivers is available from CDC at and .115

Laboratory personnel with potential exposure to virulent yellow fever virus or to concentrated preparations of yellow fever vaccine virus by direct or indirect aerosol contact should receive primary immunization with yellow fever vaccine.106 ACIP states that laboratory workers who routinely handle wild-type yellow fever virus and are at continued high risk of exposure to the virus should be tested for yellow fever virus-specific neutralizing antibody titers at least every 10 years after primary immunization to determine whether revaccination (booster dose) of the vaccine is indicated.104 (See Duration of Immunity under Cautions.)

Yellow Fever Vaccine Dosage and Administration

General

  • Because of risk of serious adverse effects in vaccine recipients (see Cautions), administer yellow fever vaccine only when clearly indicated for individuals truly at risk for exposure to yellow fever virus.100 106 115 (See Uses.)

  • Prior to administration, evaluate patient for history of sensitivity to egg or chicken protein.106 (See Allergy to Egg-related Antigens under Cautions.) If the vaccine is considered essential in an individual with history of hypersensitivity to eggs or egg products, perform sensitivity test.100 106 115 (See Sensitivity Testing and Desensitization under Cautions.)

  • In the US, yellow fever vaccine can only be administered at certain sites authorized to issue valid ICVPs.100 106 115 Vaccinees should receive a completed ICVP that is signed and validated with the official uniform stamp of the yellow fever vaccination center.100 106 115 Consult CDC or local or state public health departments for information regarding locations of these vaccination centers.115 (See Restricted Distribution under Preparations.)

Administration

Administer by sub-Q injection.106

Do not administer IM.100 However, if inadvertently given IM, ACIP states that a repeat dose given sub-Q is unnecessary since immunologic response probably not affected.100

After vaccination, observe vaccinee for at least 15 minutes for signs and symptoms of allergic reaction.100 (See Sensitivity Reactions under Cautions.)

Syncope (vasovagal or vasodepressor reaction; fainting) may occur following vaccination;134 such reactions occur most frequently in adolescents and young adults.134 Syncope and secondary injuries may be averted if vaccinees sit or lie down during and for 15 minutes after vaccination.134 If syncope occurs, observe patient until symptoms resolve.134

If multiple parenteral vaccines are administered during a single health-care visit, give each vaccine using different syringe and at a different injection site.134 Separate injection sites by at least 1 inch (if anatomically feasible) to allow appropriate attribution of any local adverse effects that may occur.134

Sub-Q Injection

In infants <12 months of age, administer sub-Q preferably into anterolateral thigh.134

In adults, adolescents, and children ≥12 months of age, administer sub-Q into upper-outer triceps area.134

To ensure appropriate delivery, make sub-Q injections at a 45° angle using a 5/8-inch, 23- to 25-gauge needle.106 134

Before withdrawing dose, carefully swirl reconstituted vaccine until a uniform suspension is obtained;106 avoid vigorous shaking to prevent foaming.106

Reconstituted vaccine should appear as a slightly pink-brown suspension;106 discard if it appears discolored or contains extraneous particulates.106

After administering vaccine, carefully dispose of vial and any unused vaccine (e.g., sterilize, discard as medical waste).106

Reconstitution

To reconstitute, withdraw volume of diluent specified by the manufacturer from the vial containing diluent (0.9% sodium chloride injection) using a syringe and slowly inject into vial of lyophilized vaccine.106 Use only the diluent supplied by the manufacturer.106

Allow reconstituted vaccine to stand for 1–2 minutes, then carefully swirl until a uniform suspension is obtained.106 Avoid vigorous shaking to prevent foaming.106

Must be administered within 1 hour following reconstitution.106

Dosage

Pediatric Patients

Prevention of Disease Caused by Yellow Fever Virus
Children and Adolescents 9 Months to 18 Years of Age
Sub-Q

Primary immunization consists of a single dose of 0.5 mL.100 106

Administer at least 10 days prior to potential exposure to yellow fever virus.100 106 115

Manufacturer recommends revaccination with a single 0.5-mL dose every 10 years in individuals at risk of exposure to yellow fever virus.106 ACIP states revaccination no longer considered necessary for most travelers, but is recommended in certain individuals (see Uses).104 WHO states revaccination every 10 years no longer considered necessary, but uncertain whether all countries with entry requirements for yellow fever vaccination will adopt this change.115 (See Duration of Immunity under Cautions.)

Adults

Prevention of Disease Caused by Yellow Fever Virus
Adults ≥19 Years of Age
Sub-Q

Primary immunization consists of a single dose of 0.5 mL.106

Administer at least 10 days prior to potential exposure to yellow fever virus.100 106 115

Manufacturer recommends revaccination with a single 0.5-mL dose every 10 years in individuals at risk of exposure to yellow fever virus.106 ACIP states revaccination no longer considered necessary for most US travelers, but is recommended in certain individuals (see Uses).104 WHO states revaccination every 10 years no longer considered necessary, but uncertain whether all countries with entry requirements for yellow fever vaccination will adopt this change.115 (See Duration of Immunity under Cautions.)

Laboratory Personnel
Sub-Q

Primary immunization consists of a single dose of 0.5 mL.106

To determine need for revaccination (booster dose) in those at continued high risk of exposure, ACIP recommends measuring yellow fever virus-specific neutralizing antibody titers at least every 10 years after primary immunization.104 If neutralizing antibody titers cannot be measured,104 ACIP recommends giving a vaccine dose every 10 years as long as laboratory worker remains at risk.104

Special Populations

Geriatric Patients

No specific dosage recommendations.106 Use with caution and consider possibility of increased risk for adverse systemic effects in this age group.100 106 115 (See Geriatric Use under Cautions.)

Cautions for Yellow Fever Vaccine

Contraindications

  • History of acute hypersensitivity to eggs, egg products, or chicken protein.106 (See Allergy to Egg-related Antigens under Cautions.)

  • Hypersensitivity to any ingredient in the formulation, including gelatin.106 (See Sensitivity Reactions under Cautions.)

  • Immunosuppression.106 (See Individuals with Altered Immunocompetence under Cautions.)

  • Immunosuppressive therapy.106 (See Specific Drugs and Laboratory Tests under Interactions.)

  • Children <9 months of age.106 (See Pediatric Use under Cautions.)

  • Nursing mothers, particularly when nursing infants are <9 months of age.106 (See Lactation under Cautions.)

Warnings/Precautions

Warnings

Vaccine-associated Neurotropic Disease

Yellow fever vaccine-associated neurotropic disease (YEL-AND; formerly known as postvaccinal encephalitis) occurs rarely following administration of yellow fever vaccine.100 106 108 115

Potentially fatal and may include meningoencephalitis (neurotropic disease), Guillain-Barré syndrome (GBS), acute disseminated encephalomyelitis, and, rarely, cranial nerve palsies.100 115

Historically, most cases reported in children <9 months of age;100 106 has now been reported in vaccinees in all age groups.115 Almost all cases reported worldwide have occurred after primary vaccination;104 115 only rarely reported following revaccination (booster dose).104

CDC estimates that the incidence of YEL-AND in vaccine recipients in the US is 0.8 cases per 100,000 doses administered, but may be 2.2 cases per 100,000 doses in vaccinees ≥60 years of age.115 In documented US cases of YEL-AND, onset of illness was 2–56 days after vaccination.115

Other adverse neurologic effects (e.g., Guillain-Barré syndrome [GBS], seizures, focal neurologic deficits) reported rarely.106

Because of risk for serious YEL-AND, use the vaccine only in individuals truly at risk for exposure to yellow fever virus.100 106 115

Promptly report any patients with symptoms suggestive of neurotropic illness following a dose of yellow fever vaccine to the Vaccine Adverse Event Reporting System (VAERS) at 800-822-7967 or .106

Vaccine-associated Viscerotropic Disease

Yellow fever vaccine-associated viscerotropic disease (YEL-AVD; previously known as febrile multiple organ system failure) reported rarely following administration of yellow fever vaccine.100 106 108 110 115 120

Resembles fulminant yellow fever caused by wild-type yellow fever virus.100 106 Varies in severity from moderate illness with focal organ dysfunction to fatal disease with overt multiple organ system failure and death.115 120

All cases reported to date worldwide have occurred after primary vaccination;100 115 laboratory-confirmed cases not reported to date following revaccination (booster dose).100 115

CDC estimates that the incidence of YEL-AVD in vaccine recipients in the US is 0.3 cases per 100,000 doses;115 incidence is higher (1.2 cases per 100,000 doses) in vaccinees ≥60 years of age and may be even higher in those ≥70 years of age.115 In US cases of YEL-AVD, median time from vaccine administration to onset of symptoms has been 4 days (range: 1–18 days) and case fatality rate has been approximately 46%.115

Risk factors for YEL-AVD include older age and history of thymus disease associated with abnormal immune cell function (e.g., myasthenia gravis, thymoma) or thymectomy.100 106 No conclusive evidence to date that this adverse effect is caused by a reversion to increased virulence in the vaccine virus.100

Because of risk for serious YEL-AVD, use the vaccine only in individuals truly at risk for exposure to yellow fever virus.100 106 115

Promptly report any patients with symptoms suggestive of viscerotropic illness following a dose of yellow fever vaccine to VAERS at 800-822-7967 or .106

Individuals with Altered Immunocompetence

Because yellow fever vaccine contains live, attenuated virus, viral replication and development of infection with the vaccine virus may be potentiated by altered immune status and risk of encephalitis or other serious adverse effects may be increased in immunocompromised individuals.100 106 134 155

Contraindicated in individuals with severe underlying disease (e.g., leukemia, lymphoma, thymic disease, generalized malignancy), gammaglobulin deficiency (e.g., agammaglobulinemia, hypogammaglobulinemia, dysgammaglobulinemia), or immunosuppression secondary to AIDS or other manifestations of HIV infection.100 106 115 Also contraindicated in individuals receiving immunosuppressive agents or immunomodulatory therapy (e.g., alkylating agents, antimetabolites, corticosteroids, interleukin-1 blocking agents, monoclonal antibodies targeting immune cells, tumor necrosis factor alpha [TNF-α] inhibitors, radiation).100 106 115 (See Specific Drugs and Laboratory Tests under Interactions.)

Evidence suggests that thymic dysfunction may be an independent risk factor for development of YEL-AVD.106 (See Vaccine-associated Viscerotropic Disease under Cautions.) Prior to administration of yellow fever vaccine, ask individuals about a history of thymus disorder (e.g., myasthenia gravis, thymoma, prior thymectomy) since the vaccine is contraindicated in such individuals.106 However, ACIP and CDC state that the vaccine can be used in individuals who have undergone incidental surgical removal of their thymus or have had direct radiation therapy in the distant past since there is no evidence of immune dysfunction or increased risk of yellow fever vaccine-associated serious adverse effects in such individuals.100 115

Advise individuals with altered immunocompetence to postpone or avoid travel to yellow fever endemic areas.106 If travel to such areas cannot be avoided, advise immunocompromised patients of the risk, give instructions on methods for avoiding bites by vector mosquitoes, and provide a medical waiver letter to use with the required ICVP to fulfill international health regulations.100 106 115 (See Medical Waivers under Cautions.)

Individuals with symptomatic HIV infection and severe immunosuppression (i.e., CD4+ T-cell count <200/mm3 in adults and children ≥6 years of age or CD4+ T-cell percentage <15% in children <6 years of age): Contraindicated.100 115

Individuals with asymptomatic HIV infection and moderate immunosuppression (i.e., CD4+ T-cell count of 200–499/mm3 in adults and children ≥6 years of age or CD4+ T-cell percentage of 15–24% in children <6 years of age): Use with caution and monitor closely for possible adverse effects.100 106 115 Because immune response may be reduced,100 103 106 115 116 consider serologic testing to document seroconversion prior to travel (see Pre- and Postvaccination Serologic Testing under Cautions).106 115

Individuals with asymptomatic HIV infection and no evidence of immunosuppression (i.e., CD4+ T-cell count ≥500/mm3 in adults and children ≥6 years of age or CD4+ T-cell percentage ≥25% in children <6 years of age): May be administered if indicated based on the destination-specific risk for exposure to yellow fever virus.100 115 155

The manufacturer, ACIP, and CDC state that family members of immunosuppressed or HIV-infected individuals may receive yellow fever vaccine, provided they have no contraindications for the vaccine.100 106 115

Sensitivity Reactions

Hypersensitivity Reactions

Anaphylaxis and other immediate hypersensitivity reactions manifested as rash, urticaria, and/or respiratory symptoms (e.g., asthma, dyspnea, bronchospasm, pharyngeal edema) reported rarely following administration of yellow fever vaccine.100 106

Hypersensitivity reactions reported principally in individuals with history of egg allergy,100 106 but anaphylaxis also reported in individuals with no history of reactions to the components of yellow fever vaccine.100

Epinephrine and other appropriate agents should be readily available in case anaphylaxis or other serious allergic reaction occurs.106

Allergy to Egg-related Antigens

Because yellow fever vaccine is produced in chick embryos, it is contraindicated in individuals with a history of acute hypersensitivity to eggs, egg products, or chicken protein.106 Less severe or localized manifestations of allergy to eggs or to feathers not considered contraindications.106

Prior to administration of yellow fever vaccine, obtain a history for evidence of sensitivity to egg or chicken protein.106 Asking individuals whether they can eat eggs without adverse effects is a reasonable screening method since individuals who are able to eat eggs or egg products generally can receive the vaccine safely.100 106 115 134

If yellow fever vaccine is considered necessary in an individual with a possible history of acute hypersensitivity to eggs or egg products, perform a skin test for hypersensitivity prior to administration of the vaccine.100 115 Less severe or localized manifestations of allergy to eggs or to feathers usually do not warrant skin testing with the vaccine.106 If vaccination is considered essential despite a positive skin test, desensitization can be considered.106 (See Sensitivity Testing and Desensitization under Cautions.)

If international travel regulations are the only reason to vaccinate an individual hypersensitive to egg or chicken protein, make efforts to obtain a medical waiver.115 (See Medical Waivers under Cautions.)

Sensitivity Testing and Desensitization

In individuals hypersensitive to eggs or chicken protein, perform a scratch and intradermal skin test prior to administration of yellow fever vaccine.106 Consider desensitization only if the vaccine is considered essential in an individual with history of severe egg sensitivity and positive sensitivity test.100 106 115

Scratch test: Use a 1:10 dilution of yellow fever vaccine in 0.9% sodium chloride.106 Place a drop of the 1:10 dilution of vaccine on a superficial scratch, prick, or puncture on the volar surface of the forearm;106 also use positive (histamine) and negative (0.9% sodium chloride) controls.106 Read scratch test after 15–20 minutes.106 A positive scratch test consists of a wheal with a diameter that is 3 mm larger than that of the 0.9% sodium chloride negative control, usually with surrounding erythema.106 The histamine control must be positive for valid interpretation.106 If scratch test is negative, perform an intradermal test.106

Intradermal skin test: Use 0.02 mL of a 1:100 dilution of yellow fever vaccine in 0.9% sodium chloride injection.106 Give intradermally on the volar surface of the forearm.106 Administer positive and negative controls intradermally concurrently at separate sites.106 A positive intradermal skin test reaction consists of a wheal that has a diameter that is at least 5 mm larger than that of the negative control and with surrounding erythema.106

Desensitization: Perform only under direct supervision of a clinician experienced in management of anaphylaxis and with necessary emergency equipment immediately available.106 Give the following increasing doses of yellow fever vaccine sub-Q at 15- to 20-minute intervals: 0.05 mL of a 1:10 dilution, 0.05 mL of undiluted vaccine, 0.1 mL of undiluted vaccine, 0.15 mL of undiluted vaccine, 0.2 mL of undiluted vaccine.106

Gelatin Sensitivity

Contains gelatin as a stabilizer.106 Consider possibility of allergic reactions in individuals sensitive to gelatin.106 134

ACIP states use vaccines containing gelatin as a stabilizer with extreme caution in individuals who have had an anaphylactic reaction to gelatin or gelatin-containing products.134

General Precautions

Acute Illness

Decision whether to administer or delay administration of yellow fever vaccine in an individual with a current or recent febrile illness depends largely on the severity and etiology of the illness.134

Manufacturer recommends deferring vaccination in individuals with acute or febrile illness, but minor acute illness with low-grade fever generally does not preclude vaccination.106

ACIP states that minor acute illness, such as mild upper respiratory infection (with or without fever) or mild diarrhea, does not preclude vaccination.134 However, vaccination of individuals with moderate or severe acute illness generally should be deferred until they have recovered from the acute phase of the illness.134

Chronic Illness

Contraindicated in individuals with chronic illness associated with altered immunocompetence.100 105 106 115 134 (See Individuals with Altered Immunocompetence under Cautions.)

Data limited regarding possible increased incidence of adverse effects or decreased vaccine efficacy if administered to patients with other chronic medical conditions (e.g., diabetes mellitus, renal disease, HCV infection or other liver disease).115 Consider use in such patients with caution, taking into account patient's general level of immune competence, disease severity and duration, and comorbidities.115

Pre- and Postvaccination Serologic Testing

Because immunocompromised individuals may have a reduced immune response to yellow fever vaccine, consider postvaccination serologic testing to document seroconversion if the vaccine is used in asymptomatic HIV-infected individuals.106 115

Because there is some evidence that the immune response to yellow fever vaccine may be lower in pregnant women than in other healthy women, consider postvaccination serologic testing to document seroconversion if the vaccine is used in a pregnant woman.100 115 (See Pregnancy under Cautions.)

ACIP recommends serologic testing at least every 10 years to determine whether revaccination with yellow fever vaccine is indicated in laboratory workers who routinely handle wild-type yellow fever virus and are at continued high risk of exposure to the virus.104

Consult appropriate state health departments or CDC (970-221-6400) for information on serologic testing.100 115

Medical Waivers

If international health regulations are the only reason to vaccinate a traveler with a contraindication to yellow fever vaccine (e.g., hypersensitivity to egg or chicken protein, immunosuppression, pregnancy), the medical contraindications to vaccination section of the ICVP should be filled out and signed by a clinician.100 115 In addition, provide a letter clearly stating the traveler's contraindication;115 the letter should be written on letterhead stationery and stamped with the uniform stamp of the yellow fever vaccination center.100 115

Issuance of a medical waiver does not guarantee its acceptance by the destination country.100 115 It also is helpful for the traveler to obtain specific and authoritative advice from the country or countries to be visited (e.g., by contacting their embassies or consulates).115 Document any waivers of requirements obtained from embassies or consulates with appropriate letters and retain for presentation with the ICVP.115

Information on country-specific requirements for yellow fever vaccination for travelers and information on regulations regarding ICVPs and medical waivers is available from CDC at .100 115

Transmission of Vaccine Virus

Yellow fever vaccine contains live, attenuated yellow fever virus.106 Low-level viremia caused by the yellow fever vaccine virus (17D-204 strain) may occur 3–7 days after vaccination and persist for 1–3 days.100 This level of viremia is high enough for the vaccine virus to be transmitted through blood products.100

Transfusion-related transmission of yellow fever vaccine virus has been documented in a few individuals who received blood products that were collected from individuals who received yellow fever vaccine 4 days before their blood donation.100 Advise vaccinees to defer blood donation for 2 weeks after receiving yellow fever vaccine.100

A least 1 case of intrauterine transmission of yellow fever vaccine virus from mother to child during pregnancy has been reported.100 115 (See Pregnancy under Cautions.)

There is evidence that yellow fever vaccine virus can be transmitted via milk to nursing infants.100 122 123 (See Lactation under Cautions.)

Limitations of Vaccine Effectiveness

May not protect all vaccine recipients against yellow fever virus infection.106

A single dose of yellow fever vaccine given 10–14 days prior to yellow fever virus exposure probably will protect most individuals.106

Data suggest the small percentage of immunologically healthy individuals who fail to develop an immune response to initial vaccination with yellow fever vaccine may do so following revaccination.106

Duration of Immunity

Duration of protection and need for revaccination or additional (booster) doses after primary immunization with yellow fever vaccine not fully determined.102 103 104 106

Following primary immunization with a single vaccine dose in healthy individuals, 80–100% of vaccinees develop protective levels of yellow fever virus neutralizing antibodies within 10 days and there is some evidence that immunity may persist for at least 30–35 years and possibly for life.100 101 103 106

Revaccination boosts levels of yellow fever virus-specific neutralizing antibody;100 106 the degree of this increase may be inversely correlated with the preexisting level of antibody.100

Manufacturer recommends revaccination every 10 years in those at risk of exposure to yellow fever virus.106

ACIP states that a single primary dose provides long-lasting protection against yellow fever virus and is adequate for most travelers.104 However, because data not available on vaccine efficacy or protective antibody titers (i.e., seroprotection) related to long-term immunogenicity after administration of yellow fever vaccine, ACIP recommends revaccination in certain individuals who may have had a less robust or less sustained immune response to the vaccine, certain travelers who will be in higher-risk settings, and laboratory personnel at continued high risk of exposure to yellow fever virus.104 (See Uses.)

WHO states that a single primary dose provides sustained immunity and lifelong protection against yellow fever virus and that revaccination (booster dose) every 10 years is no longer considered necessary.115 Although international health regulations no longer require revaccination and WHO states that an ICVP is considered valid for the lifetime of the vaccinee, it is uncertain when or if all countries with entry requirements for yellow fever vaccination will adopt this change.115 (See Uses.)

Improper Storage and Handling

Improper storage or handling of vaccines may reduce vaccine potency resulting in reduced or inadequate immune response in vaccinees.134

Inspect all vaccines upon delivery and monitor during storage to ensure that the appropriate temperature is maintained.134 (See Storage under Stability.)

Do not administer yellow fever vaccine that has been mishandled or has not been stored at the recommended temperature.134

Yellow fever vaccine is heat sensitive and potency is substantially reduced if stored at room temperature.106 This information is important for countries or areas where there is an inadequate cold chain and where there is potential for inadvertent exposure to abnormal temperatures during shipping and/or storage of the vaccine.106

If there are concerns about mishandling, contact the manufacturer or state or local immunization or health departments for guidance on whether the vaccine is usable.134

Specific Populations

Pregnancy

Category C.106

Not known whether yellow fever vaccine can cause fetal harm when administered to pregnant women.106 Animal reproduction studies not performed.106

Limited data indicate that if yellow fever vaccine is administered during pregnancy, the vaccine virus can cross the placenta and infect the developing fetus;100 106 potential risks of such congenital infection not known.115

Live, attenuated virus vaccines administered during pregnancy pose a theoretical risk to the fetus and such vaccines generally are contraindicated during pregnancy unless the disease to be prevented poses a greater risk to the pregnant woman or fetus than the vaccine.105 134

Postpone travel to areas with a substantial risk of exposure to yellow fever until after delivery.105 115

If travel to high-risk areas is unavoidable during pregnancy and the risks of the vaccine are felt to outweigh the risks of exposure to yellow fever virus, advise pregnant women of the risk, give information on methods for avoiding bites by vector mosquitoes, and provide a medical waiver letter to use with the required ICVP to fulfill international health regulations.100 105 115 (See Medical Waivers under Cautions.)

If travel to high-risk areas is unavoidable during pregnancy and the risks of exposure to yellow fever virus are felt to outweigh the risks of the vaccine (e.g., travel to high-risk area unavoidable and high level of protection against mosquito exposure not feasible), ACIP, CDC, and AAP state that yellow fever vaccine can be administered.100 105 115

If a pregnant woman receives yellow fever vaccine, monitor her infant closely for evidence of congenital infection and other possible vaccine adverse effects.115 In addition, because some data indicate lower seroconversion rates in pregnant women, consider performing serologic testing to document seroconversion after vaccination.100 115 (See Pre- and Postvaccination Serologic Testing under Cautions.)

Although specific data not available, ACIP and CDC recommend advising women who are planning to become pregnant to wait ≥4 weeks after vaccination before conceiving.100 115

Lactation

Contraindicated in nursing women, especially those with infants <9 months of age.106

ACIP and CDC state avoid yellow fever vaccine in nursing women whenever possible.100 115 However, these experts state that the vaccine can be used with caution in a nursing woman if travel with their infants to areas with substantial risk of exposure to yellow fever cannot be postponed.100 115

There is evidence that yellow fever vaccine virus can be transmitted via milk from nursing mothers to their infants.100 122 123

Pediatric Use

Contraindicated in children <9 months of age because of increased risk of serious adverse reactions in this age group, especially an increased risk of YEL-AND.106 (See Vaccine-associated Neurotropic Disease under Cautions.)

Individuals planning to travel with infants <9 months of age to areas where yellow fever is endemic or epidemic should postpone or avoid such travel, whenever possible.100 106 115

ACIP, CDC, and AAP state that there might be some situations in which vaccination of a child 6–8 months of age might be considered;100 105 115 base such decisions on the relative risk of exposure to yellow fever virus and risk of serious adverse effects associated with yellow fever vaccine.100 105 115

ACIP, CDC, and AAP state that children <6 months of age should not receive yellow fever vaccine under any circumstance.100 105 115

Geriatric Use

Adults ≥60 years of age may be at increased risk for adverse systemic effects after receiving yellow fever vaccine compared with younger adults.100 106 115

Manufacturer states limit use of yellow fever vaccine in adults >65 years of age to those traveling to or residing in known yellow fever endemic or epidemic areas.106

ACIP and CDC state use yellow fever vaccine with caution in adults ≥60 years of age, especially in those receiving their first dose of the vaccine (i.e., primary immunization).100 115

If travel is unavoidable, base decision regarding whether to vaccinate an adult ≥60 years of age on the risks and benefits of the vaccine in the context of the destination-specific risk for exposure to yellow fever virus.100 115

If use of yellow fever vaccine considered necessary in a geriatric individual, evaluate their health status prior to vaccination and carefully monitor for adverse effects for 10 days after vaccination.106

Common Adverse Effects

Low-grade fever, mild headache, myalgia, malaise, injection site reactions (edema, hypersensitivity, erythema, pain).106 115

Interactions for Yellow Fever Vaccine

Other Vaccines

Only limited data available regarding concurrent administration of yellow fever vaccine with other vaccines.106 (See Specific Drugs and Laboratory Tests under Interactions)

Make decisions regarding whether to administer yellow fever vaccine concomitantly with other vaccines based on information regarding possible interference with immune responses to the vaccines and take into consideration the convenience to the traveler in completing desired vaccinations before travel.100 106 If data not available to support concurrent administration, manufacturer states give yellow fever vaccine and the other vaccine 4 weeks apart.106

Yellow fever vaccine is a live, attenuated virus vaccine.100 106 Because of theoretical concerns that immune responses to a parenteral live virus vaccine might be impaired if given within 28–30 days (i.e., 4 weeks) of another parenteral live virus vaccine, administer either concurrently with (using different syringes and different injection sites) or at least 30 days (4 weeks) apart from other live vaccines.100 134

May be administered concurrently with (using different syringes and different injection sites) or at any interval before or after inactivated vaccines, recombinant vaccines, polysaccharide vaccines, or toxoids.100 134

Specific Drugs and Laboratory Tests

Drug or Test

Interaction

Comments

BCG vaccine

Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100

Blood products (e.g., whole blood, packed RBCs, plasma)

Blood products prepared in US unlikely to contain substantial amounts of antibody to yellow fever vaccine virus134

Yellow fever vaccine virus can be transmitted via blood products collected from individuals vaccinated a few days before their blood donation100

May be given concurrently or at any interval before or after yellow fever vaccine134

Vaccinees should defer blood donation for 2 weeks after receiving yellow fever vaccine100

Chloroquine

Inhibits replication of yellow fever virus in vitro;100 no evidence of adverse effects on antibody response to yellow fever vaccine in individuals receiving antimalarial prophylaxis100

Has been given concurrently with yellow fever vaccine106

Hepatitis A (HepA) vaccine

Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100 106 109

May be given concurrently (using different syringes and different injection sites) or at any interval before or after yellow fever vaccine100 134

Hepatitis B (HepB) vaccine

Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100 106

May be given concurrently (using different syringes and different injection sites) or at any interval before or after yellow fever vaccine100 134

Human papillomavirus vaccine (HPV)

Data not available100 106

Manufacturer of yellow fever vaccine states give 4 weeks apart since data not available regarding concurrent administration106

Immune globulin (IGIM, IGIV) or specific immune globulin (HBIG, RIG, TIG, VZIG)

No evidence that immune globulin preparations interfere with immune response to yellow fever vaccine100 105 106 111 134

Yellow fever vaccine may be given concurrently (using different syringes and different injection sites) or at any time before or after immune globulin preparations105 134

Immunosuppressive or immunomodulatory agents (e.g., alkylating agents, antimetabolites, corticosteroids, interleukin-1 blocking agents, monoclonal antibodies targeting immune cells, tumor necrosis factor alpha [TNF-α] inhibitors, radiation)

Potential for decreased or suboptimal antibody response to yellow fever vaccine and increased risk of adverse effects (e.g., encephalitis)100 106 114 115 134

Short-term (<2 weeks), low- to moderate-dose (e.g., <20 mg of prednisone daily or equivalent) systemic corticosteroid therapy; long-term, alternate-day therapy with short-acting corticosteroids; maintenance physiologic doses (replacement therapy); topical corticosteroids (e.g., cutaneous, ophthalmic); inhaled corticosteroids; or intra-articular, bursal, or tendon injections with corticosteroids should not be immunosuppressive134

Yellow fever vaccine contraindicated in individuals receiving immunosuppressive or immunomodulatory therapy100 106 115

Postpone vaccination and avoid travel to yellow fever endemic areas until immunosuppressive or immunomodulatory therapy discontinued and immune function improves106

Influenza vaccine

Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100

Japanese encephalitis virus vaccine

Data not available100 106

Manufacturer of yellow fever vaccine states give 4 weeks apart since data not available regarding concurrent administration106

Measles, mumps, and rubella vaccine (MMR)

Has been given either concurrently (at a different site) or 30 days after MMR;117 antibody responses to measles antigen were similar with both schedules, but seroconversion rates to mumps, rubella, and yellow fever antigens were lower when the vaccines were given concurrently compared with 30 days apart117

May be given concurrently (using different syringes and different injection sites) with yellow fever vaccine;134 if not given concurrently, give at least 4 weeks apart100 106 115 134

Meningococcal vaccine

MPSV4 (Menomune): Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100 106

Meningococcal vaccine: May be given concurrently (using different syringes and different injection sites) or at any interval before or after yellow fever vaccine100 134

Poliovirus vaccine inactivated (IPV)

Has been given concurrently with yellow fever vaccine without interference with immune responses or increased adverse effects100

May be given concurrently (using different syringes and different injection sites) or at any interval before or after yellow fever vaccine100 134

Rabies vaccine

Data not available100 106

Manufacturer of yellow fever vaccine states give 4 weeks apart since data not available regarding concurrent administration106

Tuberculin

Effect of yellow fever vaccine, if any, on tuberculin testing not determined;134 another live virus vaccine (measles vaccine) reported to temporarily suppress tuberculin skin sensitivity134

ACIP states a tuberculin skin test can be given during the same health-care visit as yellow fever vaccine;134 if not given simultaneously, tuberculin test should be delayed until ≥4 weeks after the vaccine dose134

Do not delay vaccination with yellow fever vaccine based only on theoretical concern about a possible interaction with tuberculin skin testing134

Typhoid vaccine

Oral live typhoid vaccine (Vivotif): Concurrent administration with yellow fever vaccine does not interfere with immune response to the typhoid antigen113

Parenteral inactivated typhoid vaccine (Typhim Vi): Has been given concurrently with yellow fever vaccine with or without concomitant HepA vaccine (Vaqta) or meningococcal vaccine (Menveo) without any apparent decrease in immune responses or increase in adverse effects109 121

Oral live typhoid vaccine (Vivotif): May be given concurrently or at any interval before or after yellow fever vaccine100

Parenteral inactivated typhoid vaccine (Typhim Vi): May be given concurrently (using different syringes and different injection sites) or at any interval before or after yellow fever vaccine100 134

Varicella vaccine

Data not available100

Manufacturer of yellow fever vaccine states administer 4 weeks after yellow fever vaccine since no data available regarding concurrent administration106

Stability

Storage

Parenteral

For Injection, for Sub-Q Use

Prior to reconstitution, store at 2–8°C.106 Do not freeze.106

Discard reconstituted yellow fever vaccine if not used within 1 hour.106

Yellow fever vaccine does not contain thimerosal or any other preservatives.106

Actions

  • Yellow fever vaccine available in US is a lyophilized preparation of live, attenuated organisms of the 17D-204 strain of yellow fever virus.106 The vaccine is prepared by culturing the 17D-204 strain of live yellow fever virus in living chick embryos free of avian leukosis virus (ALV).106

  • Each 0.5-mL of the vaccine contains ≥4.74 log10 plaque-forming units (PFU) throughout the life of the product.106

  • Yellow fever is transmitted by mosquito vectors.100 106 115 The disease has an abrupt onset after an incubation period of 3–6 days.100 106 A subclinical illness and influenza-like syndrome may occur or the disease may progress to an overwhelming pansystemic disease with hepatic and renal failure and hemorrhage caused by platelet and clotting abnormalities.106 108 115

  • Yellow fever vaccine stimulates active immunity to yellow fever virus infection by inducing production of yellow fever virus-specific IgM neutralizing antibodies.106 Immune response to the vaccine is similar to that induced by wild-type infection.106

  • Anti-yellow fever antibodies are detectable in most individuals within 10–14 days after a single dose of yellow fever vaccine.106

  • Yellow fever vaccine is highly immunogenic in most adults, adolescents, and children >9 months of age.106 In US studies using the currently available vaccine, the seroconversion rate was 80–100% in adults.100 106 Although there was no evidence of age-related differences in the immune response to the vaccine in early studies,103 106 more recent studies suggest that children have lower immune responses than adults and that the difference in seroconversion rates is most pronounced in children 9–36 months of age.103

  • Reduced immune responses to yellow fever vaccine and lower antibody titers may occur in immunocompromised individuals (e.g., HIV-infected individuals).100 103 106 115 116

  • Seroconversion rate after vaccination in pregnant women may be reduced compared with that in other healthy women, especially when the vaccine is given late in pregnancy.100 103 106

  • The minimum titer of anti-yellow fever antibodies conferring protection against yellow fever not definitely established to date.106 WHO considers a log10 neutralization index of ≥0.7 measured by a plaque reduction assay to be indicative of an adequate response to yellow fever vaccine and this was the level used to define seroconversion in clinical trials of the vaccine.106

Advice to Patients

  • Prior to administration of the vaccine dose, provide a copy of the appropriate CDC Vaccine Information Statement (VIS) to the patient or patient's legal representative (VISs are available at ).112

  • Advise patient and/or patient's parent or guardian of the risks and benefits of vaccination with yellow fever vaccine.106

  • Advise patient and/or patient's parent or guardian that yellow fever vaccine should not be used in individuals with life-threatening allergic reactions to eggs, egg products, or chicken protein, vaccine ingredients or packaging components (e.g., gelatin), or a previous dose of the vaccine.106 Importance of informing clinician of any history of sensitivity to egg or chicken protein since sensitivity testing may be necessary prior to vaccination.106 (See Sensitivity Reactions under Cautions.)

  • Importance of informing clinicians if the patient has a weakened immune system (e.g., leukemia, lymphoma, HIV/AIDS, thymic disease) or is receiving treatment that may weaken the immune system (e.g., high-dose corticosteroids).

  • Advise patient and/or patient's parent or guardian that yellow fever vaccine is given only at certain vaccination centers authorized to issue valid ICVPs and that the completed document will be needed as proof of vaccination before the individual is allowed to enter certain countries.100 106 115 Current information regarding which countries are in yellow fever endemic zones and/or have vaccination requirements for entry is available at CDC website ().115

  • Advise patient and/or patient's parent or guardian that yellow fever vaccine may not provide protection in all vaccinees.106 In addition to being vaccinated, importance of avoiding exposure to mosquitoes while in yellow fever endemic areas (e.g., stay in air-conditioned or well-screened areas, wear long-sleeved shirts and long pants to cover the body, use appropriate insect repellents, use mosquito nets between dusk and dawn).115

  • Advise patient and/or patient's guardian of the signs and symptoms of an allergic reaction (e.g., urticaria, angioedema, rash, dyspnea, bronchospasm, pharyngeal edema, wheezing, throat tightness) and importance of immediately contacting a clinician if any symptoms of an allergic reaction develop following vaccination.100

  • Importance of informing clinicians if any adverse reactions (including allergic reactions) occur ≤30 days after vaccination with yellow fever vaccine.106 Clinicians or individuals can report any adverse reactions that occur following vaccination to VAERS at 800-822-7967 or .106

  • Advise individuals ≥60 years of age that they may be at increased risk for adverse effects after receiving yellow fever vaccine compared with younger adults.106 115 (See Geriatric Use under Cautions.)

  • Advise patients with young children that yellow fever vaccine should not be used in infants <9 months of age and of the importance of avoiding yellow fever endemic areas if traveling with children in this age group.106 (See Pediatric Use under Cautions.)

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.106

  • Importance of women informing clinicians if they are or plan to become pregnant.106 Advise such women that the vaccine should be used during pregnancy only when clearly needed and that efforts should be made to postpone travel to yellow fever endemic areas until after delivery. 106 If travel to yellow fever endemic areas cannot be avoided during pregnancy, discuss the risks and benefits of vaccination. (See Pregnancy under Cautions.)

  • Importance of women informing clinicians if they plan to breast-feed.106 Advise such women that the vaccine is not recommended for use in nursing women, particularly when breast-feeding infants are <9 months of age.106 (See Lactation under Cautions.)

  • Importance of informing patients of other important precautionary information.106 (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

In the US, yellow fever vaccine is supplied only to designated Yellow Fever Vaccination Centers authorized to issue valid ICVPs for documentation of vaccination against yellow fever.100 106 115 Consult CDC yellow fever vaccination clinic search page at or local or state public health departments for information regarding the location of these vaccination centers.100 106 115

Sanofi Pasteur announced that YF-VAX, the only yellow fever vaccine licensed in the US, may be unavailable from mid-2017 until mid-2018 because of production delays.124 125 FDA is allowing a similar yellow fever vaccine manufactured by Sanofi Pasteur in France (Stamaril) to be available in the US under an expanded access investigational new drug (IND) protocol for use when YF-VAX becomes unavailable.124 125 Stamaril is registered and distributed in more than 70 countries, but considered investigational in the US.124 125 Stamaril will be provided at only a limited number of designated Yellow Fever Vaccination Centers;124 125 consult CDC yellow fever vaccination clinic search page to find such clinics.124 125

Yellow Fever Vaccine

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Parenteral

For injection, for sub-Q use

≥4.74 log10 plaque-forming units (PFU) per 0.5 mL

YF-VAX

Sanofi Pasteur

AHFS DI Essentials. © Copyright 2017, Selected Revisions July 10, 2017. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

† Use is not currently included in the labeling approved by the US Food and Drug Administration.

References

100. Staples JE, Gershman M, Fischer M et al. Yellow fever vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2010; 59(RR-7):1-27. [PubMed 20671663]

101. . Vaccines and vaccination against yellow fever. WHO position paper -- June 2013. Wkly Epidemiol Rec. 2013; 88:269-83. [PubMed 23909008]

102. Collaborative group for studies on yellow fever vaccines. Duration of post-vaccination immunity against yellow fever in adults. Vaccine. 2014; 32:4977-84. [PubMed 25090646]

103. Gotuzzo E, Yactayo S, Córdova E. Efficacy and duration of immunity after yellow fever vaccination: systematic review on the need for a booster every 10 years. Am J Trop Med Hyg. 2013; 89:434-44. [PubMed 24006295]

104. Staples JE, Bocchini JA, Rubin L et al. Yellow Fever Vaccine Booster Doses: Recommendations of the Advisory Committee on Immunization Practices, 2015. MMWR Morb Mortal Wkly Rep. 2015; 64:647-50. [PubMed 26086636]

105. American Academy of Pediatrics. Red Book: 2015 Report of the Committee on Infectious Diseases. 30th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2015.

106. Sanofi Pasteur. YF-VAX (yellow fever vaccine) yellow fever virus strain 17d-204 live antigen injection, powder, lyophilized, for suspension) prescribing information. Swiftwater, PA; 2016 Feb.

108. Centers for Disease Control and Prevention. Adverse events associated with 17D-derived yellow fever vaccination—United States, 2001-2002. MMWR Morb Mortal Wkly Rep. 2002; 51:989-93. [PubMed 12455906]

109. Jong EC, Kaplan KM, Eves KA et al. An open randomized study of inactivated hepatitis A vaccine administered concomitantly with typhoid fever and yellow fever vaccines. J Travel Med. 2002; 9:66-70. [PubMed 12044272]

110. Martin M, Tsai TF, Cropp B et al. Fever and multisystem organ failure associated with 17D-204 yellow fever vaccination: a report of four cases. Lancet. 2001; 358:98-104. [PubMed 11463410]

111. Edupuganti S, Eidex RB, Keyserling H et al. A randomized, double-blind, controlled trial of the 17D yellow fever virus vaccine given in combination with immune globulin or placebo: comparative viremia and immunogenicity. Am J Trop Med Hyg. 2013; 88:172-7. [PubMed 23208880]

112. Centers for Disease Control and Prevention. Yellow fever vaccine information statement. 2011 Mar 30. From CDC website.

113. Crucell Vaccines Inc. Vivotif (tyhpoid vaccine live oral TY21a) prescribing information. Miami Lakes, FL; 2013 Sep.

114. Kernéis S, Launay O, Ancelle T et al. Safety and immunogenicity of yellow fever 17D vaccine in adults receiving systemic corticosteroid therapy: an observational cohort study. Arthritis Care Res (Hoboken). 2013; 65:1522-8. [PubMed 23554297]

115. Centers for Disease Control and Prevention. CDC health information for international travel, 2016. Atlanta, GA: US Department of Health and Human Services. Updates may be available at CDC website.

116. Sidibe M, Yactayo S, Kalle A et al. Immunogenicity and safety of yellow fever vaccine among 115 HIV-infected patients after a preventive immunisation campaign in Mali. Trans R Soc Trop Med Hyg. 2012; 106:437-44. [PubMed 22627101]

117. Nascimento Silva JR, Camacho LA, Siqueira MM et al. Mutual interference on the immune response to yellow fever vaccine and a combined vaccine against measles, mumps and rubella. Vaccine. 2011; 29:6327-34. [PubMed 21640779]

120. DeSilva M, Sharma A, Staples E et al. Notes from the field: fatal yellow Fever vaccine-associated viscerotropic disease - Oregon, september 2014. MMWR Morb Mortal Wkly Rep. 2015; 64:279-81. [PubMed 25789744]

121. Alberer M, Burchard G, Jelinek T et al. Safety and immunogenicity of typhoid fever and yellow fever vaccines when administered concomitantly with quadrivalent meningococcal ACWY glycoconjugate vaccine in healthy adults. J Travel Med. 2015 Jan-Feb; 22:48-56. [PubMed 25308927]

122. Kuhn S, Twele-Montecinos L, MacDonald J et al. Case report: probable transmission of vaccine strain of yellow fever virus to an infant via breast milk. CMAJ. 2011; 183:E243-5. [PubMed 21324845]

123. Centers for Disease Control and Prevention (CDC). Transmission of yellow fever vaccine virus through breast-feeding - Brazil, 2009. MMWR Morb Mortal Wkly Rep. 2010; 59:130-2. [PubMed 20150888]

124. Sanofi Pasteur. Yellow fever vaccine access. From Sanofi Pasteur US website. Accessed 2017 May 1.

125. Gershman Md, Angelo KM, Richey J. Addressing a yellow fever vaccine shortage - United States, 2016-2017. MMWR Morb Mortal Wkly Rep. 2017; 66:457-9. [PubMed 28472025]

134. National Center for Immunization and Respiratory Diseases. General recommendations on immunization --- recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2011; 60:1-64. [PubMed 21293327]

155. Panel on Opportunistic Infection in HIV-infected Adults and Adolescents, US Department of Health and Human Services (HHS). Guidelines for the prevention and treatment of opportunistic infections in HIV-infected adults and adolescents: recommendations from the Centers for Disease Control and Prevention, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America (September 17, 2015). Updates may be available at HHS AIDS Information (AIDSinfo) website.

Hide