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Human H5N1 Virus Replikin Count Overtakes That in H5N1 Bird Flu

BOSTON, Dec. 28, 2006 -- A common question asked at current scientific conferences is: "Where did bird flu go?"

The recent decrease in reported H5N1 human cases and bird outbreaks might indicate that the virus has become dormant. However, quantitative analysis by Replikins, Ltd. released yesterday of human H5N1 virus sequences in 2006 has found that the Replikin Count(TM) has significantly increased beyond all annual previous levels reported in chickens and humans. The Replikin Count(TM) determined by virus protein software analysis, provides an index of the capacity for virus rapid replication. The Replikin Count(TM) is defined as the number of replikin peptide sequences per 100 amino acids of virus protein, that is concentration, and is independent of the number of specimens examined.

Rather than declining, the Replikin Count(TM) in humans in 2006 has risen 35% over that in 2005, and outstripped the Count in all reported chicken H5N1 virus specimens, both with reference to the mean and the range, of the peptides in all human H5N1 virus specimens reported by the National Library of Medicine.

With the rise in Replikin Count(TM) in human H5N1, (3.7(+/-4.1) in 2005 to 5.0(+/-5.9) in 2006, p<0.001), the human Count exceeds that for H5N1 in chickens, which after rising from 2003, has been constant (3.2(+/-2.8) in 2005, and 3.2(+/-3.1) in 2006. The Replikin Count(TM) in H5N1 is now seen to have risen steadily, by a factor of 3.9 from the 1998 Replikin Count(TM) of 1.3(+/-0.4) in chickens to the Replikin Count(TM) in humans in 2006 of 5.0(+/-5.9) (p<0.001). The Replikin Count in the 1918 H1N1 influenza pandemic was 7.0. The mortality rate in human H5N1 cases has also increased 2.3 times, from 26 percent in 1997-98 to approximately 60 percent in 2006.

The increase in Replikin Count(TM) could have provided early warning of the last three H5N1 bird outbreaks (2001-2006). It was also found to precede or was an early association of the three influenza human pandemics - 1918 (H1N1), 1957 (H2N2) and 1968 (H3N2), and the H5N1 outbreak in Hong Kong (1997) (see for detailed data).

In contrast to H5N1, Replikin Count(TM) analyses of H3N2 influenza virus (the cause of the pandemic of 1968) has decreased (2.7(+/-0.6) in 2005 to 0.8(+/-1) in 2006, p<0.001). Such decreases have been associated with periods of relative viral quiescence.

"This rise in human H5N1 Replikin Count(TM) suggests that the replication rate of this virus in humans continues to increase. Humans may be becoming a preferred host for H5N1," according to Dr. Sam Bogoch, Chairman of Replikins, Ltd.

"The Replikin Count(TM) is specific to the virus strain, the host species, and the region, and can be used to indicate the threat level of a particular virus. We know of no other quantitative measures of particular peptide sequences of virus proteins, or of any other chemical constituent, which have this correlative and predictive value" he said.

In addition to FluForecast(R), Replikins, Ltd. has enlisted an international "Replikins Group" of several universities and research institutions to test the effect of its potential synthetic replikins vaccines and other products against these new targets related to rapid replication in H5N1 and other virus disorders.


Samuel Bogoch, M.D., Ph.D. Chairman Replikins, Ltd. 38 The Fenway Boston MA 02215 Ph. 646-320-5910

Carol Zepp PR 101 Ph. 978-500-5030

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Posted: January 2007