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Reprinted from Cayman Net News
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Letter: Spread of avian flu by drinking water
Published on Tuesday, January 22, 2008


Dear Sir,

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.

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. Infected poultry can everywhere contaminate the drinking water. All humans have contact to drinking water. Special in cases of small water supplies this pathway can explain small clusters in households.

In hot climates and the tropics flood-related influenza is typical after extreme weather and natural after floods.

The virulence of the influenza virus depends on temperature and time. If young and fresh H5N1 contaminated water from low local wells, cisterns, tanks, rain barrels or rice fields is used for water supply the water temperature for infection may be higher (at 24°C the virulence of influenza viruses amount to 2 days) as 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 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.

In temperate climates strong seasonal waterborne infections like the norovirus, rotavirus, salmonella, campylobacter and - differing from the usual dogma - influenza are mainly triggered by drinking water, dependent on the water’s temperature (in Germany it is at a minimum in February and March and at a maximum in August). There is no evidence that influenza primarily is transmitted by saliva droplets.

In temperate climates the strong interdependence between influenza infections and environmental temperatures can’t be explained by the primary biotic transmission by saliva droplets from human to human at temperatures of 37.5°C. There must be an abiotic vehicle like cold drinking water. There is no other appropriate abiotic vehicle.

In Germany about 98 percent of inhabitants have a central public water supply with older and better protected water. Therefore, in Germany cold water is decisive to the virulence of viruses.

Dipl.-Ing. Wilfried Soddemann
Free Science Journalist