SCIENTISTS WARN H5N1 BIRD FLU SPREADING TO HUMANS FROM PIGEONS OCTOBER 2...: http://t.co/GBIekov0 via @youtube
The global spread of highly pathogenic H5N1 influenza in birds is considered a significant pandemic threat.
While other H5N1 influenza strains are known, they are significantly different from a current, highly pathogenic H5N1 strain on a genetic level, making the global spread of this new strain unprecedented. The H5N1 strain is a fast-mutating, highly pathogenic avian influenza virus (HPAI) found in multiple bird species. It is both epizootic (an epidemic in non-humans) and panzootic (a disease affecting animals of many species especially over a wide area). Unless otherwise indicated, "H5N1" in this timeline refers to the recent highly pathogenic strain of H5N1.
"Since 1997, studies of H5N1 influenza indicate that these viruses continue to evolve, with changes in antigenicity and internal gene constellations; an expanded host range in avian species and the ability to infect felids; enhanced pathogenicity in experimentally infected mice and ferrets, in which they cause systemic infections; and increased environmental stability."[1]
Cumulative Human Cases of and Deaths from H5N1
As of April 11, 2007
Notes:
Source WHO Confirmed Human Cases of H5N1
"[T]he incidence of human cases peaked, in each of the three years in which cases have occurred, during the period roughly corresponding to winter and spring in the northern hemisphere. If this pattern continues, an upsurge in cases could be anticipated starting in late 2006 or early 2007." Avian influenza -- epidemiology of human H5N1 cases reported to WHO
The regression curve for deaths is y = a + ek x, and is shown extended through the end of April, 2007.
Tens of millions of birds have died of H5N1 influenza and hundreds of millions of birds have been slaughtered and disposed of, to limit the spread of H5N1. Countries that have reported one or more major highly pathogenic H5N1 outbreaks in birds (causing at least thousands but in some cases millions of dead birds) are (in order of first outbreak occurrence): South Korea, Vietnam, Japan, Thailand, Cambodia, Laos, Indonesia, China, Malaysia, Russia, Kazakhstan, Mongolia, Turkey, Romania, Croatia, Ukraine, Cyprus, Iraq, Nigeria, Egypt, India, France, Niger, Bosnia, Azerbaijan, Albania, Cameroon, Myanmar, Afghanistan, Israel, Pakistan, Jordan, Burkina Faso, Germany, Sudan, Ivory Coast, Djibouti, Hungary, United Kingdom, Kuwait, Bangladesh, Saudi Arabia, Ghana, Czech Republic, Togo, Nepal.
H5N1
Influenza A virus
subtype H5N1
Genetic structure
Infection
Human mortality
Global spread
in 2004
in 2005
in 2006
in 2007
Social impact
Pandemic
Vaccine
v t e
Highly pathogenic H5N1 has been found in birds in the wild in numerous other countries: Austria, Bulgaria, Denmark, Greece, Iran, Italy, Poland, Serbia and Montenegro, Slovakia, Slovenia, Spain, Sweden, Switzerland. Surveillance of H5N1 in humans, poultry, wild birds, cats and other animals remains very weak in many parts of Asia and Africa. Much remains unknown about the exact extent of its spread.
H5N1 has low pathogenic varieties endemic in birds in North America. H5N1 has a highly pathogenic variety that is endemic in dozens of species of birds throughout south Asia and parts of Africa. So far, it is very difficult for humans to become infected with H5N1. The presence of highly pathogenic (deadly) H5N1 around the world in both birds in the wild (swans, magpies, ducks, geese, pigeons, eagles, etc.) and in chickens and turkeys on farms has been demonstrated in millions of cases with the virus isolate actually sequenced in hundreds of cases yielding definitive proof of the evolution of this strain of this subtype of the species Influenzavirus A (bird flu virus).
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