A big fear among health officials is that the bird flu will acquire the ability to jump easily between humans, leading to a pandemic and millions of deaths .In 1957 Robert G. (Rob) Webster (born May 7, 1932)(avian influenza expert)was the first to announce a link between human flu and bird flu.
What is Bird flu?
"Bird flu" is a phrase similar to "Swine flu", "Dog flu", "Horse flu", or "Human flu" in that it refers to an illness caused by any of many different strains of influenza viruses that have adapted to a specific host. All known viruses that cause influenza in birds belong to the species: Influenza A virus. All subtypes (but not all strains of all subtypes) of Influenza A virus are adapted to birds, which is why for many purposes avian flu virus is the Influenza A virus (note that the "A" does not stand for "avian").
Influenza virus A is a genus of the Orthomyxoviridae family of viruses. Influenza virus A includes only one species: influenza A virus which causes influenza in birds, humans, pigs, and horses.
What is human flu?
Human flu refers to a subset of Orthomyxoviridae that create influenza in humans and are endemic in humans. This is not a phylogenetics based taxonomic category.The species of Orthomyxoviridae that can cause flu in humans are Influenza A virus, Influenza B virus and Influenza C virus but not all genotypes of these three species infect humans.
Outbreak:
The global spread of highly pathogenic H5N1 in birds is considered a significant pandemic threat. While other H5N1 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).
Bird Flu Transmission:
• Direct contact with secretions from infected birds, excretion especially feces
• Contaminated feed, water, equipment and clothing
• Clinically normal waterfowl and sea birds may introduce the virus into flocks
• Broken contaminated eggs may infect chicks in the incubator
Sources of Virus
• Feces, respiratory secretions
• Highly pathogenic viruses may remain viable for long period of time in infected feces, tissues and water
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Spread of avian flu by drinking water
There is a widespread link between avian flu and water, e.g. in Egypt to the Nile delta or Indonesia to residential districts of less prosperous humans with backyard flocks and without central water supply as in Vietnam:
http://www.cdc.gov/ncidod/EID/vol12no12/06-0829.htm.
See also the WHO web side:
http://www.who.int/water_sanitation_health/emerging/h5n1background.pdf and
http://www.umg-verlag.de/umwelt-medizin-gesellschaft/407_m_s.html
“Influenza: Initial introduction of influenza viruses to the population via abiotic water supply versus biotic human viral respirated droplet shedding” and http://www.thelancet.com/journals/laninf/article/PIIS1473309907700294/abstract?iseop=true
“Transmission of influenza A in human beings”.
Avian flu infections may increase in consequence to increase of virus circulation. Transmission of avian flu by direct contact to infected poultry is an unproved assumption from the WHO. There is no evidence that influenza primarily is transmitted by saliva droplets.
Infected birds and poultry can everywhere contaminate the drinking water. All humans have very intensive contact to drinking water. To prove viruses in water is difficult because of dilution. If you find no viruses you can not be sure that there are not any. On the other hand in water viruses remain virulent for a long time. Water has to be tested for influenza viruses by cell culture and in particular by the more sensitive molecular biology method PCR.
In hot climates/the tropics flood-related influenza is typical after extreme weather and floods. Virulence of influenza viruses depends on temperature and time. Special in cases of local water supplies with “young” and fresh H5N1 contaminated water from low local wells, cisterns, tanks, rain barrels, ponds, rivers or rice paddies this pathway can explain small clusters in households. At 24°C e.g. in the tropics the virulence of influenza viruses in water amount to 2 days. In temperate climates for “older” water from central water supplies cold water is decisive to virulence of viruses. At 7°C the virulence of influenza viruses in water amount to 14 days.
Human to human and contact transmission of influenza occur - but are overvalued immense. In the course of influenza epidemics in Germany, recognized clusters are rare, accounting for just 9 percent of cases e.g. in the 2005 season. In temperate climates the lethal H5N1 virus will be transferred to humans via cold drinking water, as with the birds in February and March 2006, strong seasonal at the time when drinking water has its temperature minimum.
The performance to eliminate viruses from the drinking water processing plants regularly does not meet the requirements of the WHO and the USA/USEPA. Conventional disinfection procedures are poor, because microorganisms in the water are not in suspension, but embedded in particles. Even ground water used for drinking water is not free from viruses.
Dipl.-Ing. Wilfried Soddemann - Free Science Journalist - soddemann-aachen@t-online.de
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