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Published online 17 December 2007 | Nature | doi:10.1038/news.2007.383
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Large bird flu cluster emerges
Human cases in Pakistan could hint of person-to-person spread.
A team of experts from the World Heath Organization (WHO) is making its way north in Pakistan to investigate a cluster of at least eight cases of avian flu in people living near the Afghan border. They will be seeking to establish whether the disease is spreading, and whether the cases were caused by human-to-human transmission.
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This outbreak already has set a record for the most contradictions published in 7 days or less. Every major point has at least two mutually exclusive stories related to disease onset dates as well as disease onset. Media reports indicate the larger cluster began with a cull October 21-23. The index case was a veterinarian, who developed symptoms on October 25, and 4 of 40 samples collected on or before October 30 were H5N1 positive. The two brothers were said to have died on November 19 and 29, but even the back end of the transmission chain is contradicted. A health care worker has been said to have tested positive on an "unreliable" test. One report says she was asymptomatic, while another said she had symptoms. Similarly, a brother residing in the US traveled to Pakistan for the funeral(s). One report said he returned with mild symptoms, saw a US doctor, and tested negative, while another report said he had no symptoms (and an earlier report said he tested positive in Pakistan). Thus, the most important aspects of this cluster (disease onset and disease onset dates), remain confused, at best.
The latest media report (Bloomberg) indicates a Tamiflu blanket was placed over contacts in Pakistan, but samples were collected for testing one to two days after the start of treatment. These collections can mask the spread of H5N1 because oseltamivir can lower viral RNA to levels below detection. Follow-up on H5 antibody levels in these patients would be useful for determining the extent of H5N1 spread among patients and contacts.
H5N1 avian flu: Spread by drinking water into small clusters: Human to human and contact transmission of influenza occur - but are overvalued immense. In the course of Influenza epidemics in Germany recognized clusters are rarely (9% of the cases in the season 2005). In temperate climates the lethal H5N1 avian flu virus will be transferred to humans strong seasonal in the cold via cold drinking water, as with the birds feb/mar 2006. Recent research must worry: So far the virus had to reach the bronchi and the lungs in order to infect humans. Now it infects the upper respiratory system (mucous membranes of the throat e.g. when drinking and mucous membranes of the nose and probably also the conjunctiva of the eyes as well as the eardrum e.g. at showering). In a few cases (Viet Nam, Thailand) stomach and intestine by the H5N1 virus were stricken but not the bronchi and the lungs. The virus might been orally taken up, e.g. when drinking contaminated water. The performance to eliminate viruses of the drinking water processing plants in Germany 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 the strong seasonal waterborne infections like norovirus, rotavirus, salmonellae, campylobacter and - differing from the usual dogma - influenza are mainly triggered by drinking water dependent on the drinking water temperature (in Germany minimum feb/mar – maximum august). There is no evidence that influenza primary is transmitted by saliva droplets. In temperate climates the strong interdependence between influenza infections and environmental temperatures can’t be explained with the primary biotic transmission by saliva droplets from human to human with 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% of inhabitants have a central public water supply with older and better protected water. Therefore in Germany cold water is decisive to virulence of viruses. In hot climates/tropics the flood-related influenza is typical after extreme weather and natural after floods. Virulence of 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 water temperature for infection may be higher as in temperate climates. Dipl.-Ing. Wilfried Soddemann eMail soddemann-aachen@t-online.de http://www.dugi-ev.de/information.html Epidemiological Analysis: http://www.dugi-ev.de/TW_INFEKTIONEN_H5N1_20071019.pdf
Pardon me for being non-academic for a moment, but could we hope this disease could get Osama bin Laden and his Taliban comrades?
It would be all right if it could get a particular American president too.
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Let's see: Al Queda engineers a pandemic form of the H5N1 virus and then spreads it around in a remote village to get it started. Right. That would only be added incompentence on top of the fact that they would have failed to create the kind of quick-spreading virus that could be a genuine pandemic virus. Then again, while I don't think that this outbreak is work of Al Queda, I do agree with you that the risk of Al Queda trying to create a pandemic H5N1 virus is real.
Letting aside political considerations it is extremely important to determine the extension of this possible "only human cluster". The virus ability to "humanize" is like a Russian Roulette where if the bullet finds the hole a single dead can be expected. In this case would be more than one. Odds increase proportionately to the number of infected (human/animal) beings introducing in each new event slight changes in virus DNA. Anyone of this changes could be a nightmare Bingo.
Recent media reports describe a male doctor hospitalized at the Khyber Teaching Hospital (KTH). The index case for the large cluster is a veterinarian who organized a cull October 21-23. He developed symptoms on October 25 and was hospitalized at KTH. His brothers, who were students and not involved in the cull, visited him there. They were subsequently hospitalized at KTH and died there on November 19 and 29. Earlier media reports described a female health care work who tested positive on an initial H5N1 test, If the two health care workers described in media reports are unique, and they became infected by the familial cluster members, then the transmission chain of almost two months, would be an H5N1 record.