Sunday, December 04, 2005
Bird Flu News From Asia
Vietnam has been more open than most other Asian countries about their battle with H5N1, and so I place much importance on their accounts. There also were changes to the H5N1 strains and a different case pattern between north and south Vietnam noted this summer. The emergence of milder cases with a higher survival rate might have signaled at least one strain of H5N1 adapting to humans.
On December 1st, a report appeared of 5 to 10 pneumonia patients a day (CurEvents.com thread) being admitted at Bach Mai hospital:
Health care workers in Indonesia have complained that they have gotten ill from treating bird flu victims. I don't think that H2H can be too far away, although I doubt that it will be all that efficient at first. Before widespread deaths the virus has to become efficient at infecting victims.
Recent developments in Asia point to human clusters. The latest cluster in Indonesia:
Even WHO concedes that this latest cluster may indicate human to human transmission:
In the Americas we are still ramping up bird-testing programs. Maybe we should turn our attention to human testing programs. I doubt we are going to catch the first H5N1 cases in the US for several months. This is why I am watching the CDC's morbidity and mortality report. Click on mortality tables at the bottom of the screen and then you can see figures for pneumonia/flu deaths from selected US cities by week and year (for comparison purposes). You need to compare same city to same city for the previous two years, because average death rates will differ between cities.
On December 1st, a report appeared of 5 to 10 pneumonia patients a day (CurEvents.com thread) being admitted at Bach Mai hospital:
The Hospital for Tropical Diseases said it receives five to 10 cases of suspected bird flu everyday and the condition of some of the patients is worsening. Some are hospitalised in the morning but their lungs are severely damaged by the afternoon.A commenter on the CurEvents.com thread wrote this:
However, there hasn’t been any official conclusion about the cause for their disease because almost all the cases being treated in the hospital show negative response to the test for H5N1 avian virus.
Most likely they are testing for it using PCR--that's the only way they can get results so quickly. PCR requires the primers being exactly the same as the H5N1 sequence. Most likely they are using primers designed for the H5N1 that has been in Vietnam for the last year, and now those primers are not working for the new, highly pathogenic Qinghai Lake H5N1 that has arrived very recently--that has the same effect on birds in the Crimea. We should get more results soon hopefully. Alternatively, it could have recombined or reassorted.This raises questions about testing and clinical surveillance in the west. It's not that easy to determine exact flu strains circulating among humans, which is why it is taking an average of more than three weeks to get confirmation of Indonesian H5N1 cases from Hong Kong. All of this raises questions about how efficient European and American hospitals will be about detecting H5N1 cases when they start to pop up.
Health care workers in Indonesia have complained that they have gotten ill from treating bird flu victims. I don't think that H2H can be too far away, although I doubt that it will be all that efficient at first. Before widespread deaths the virus has to become efficient at infecting victims.
Recent developments in Asia point to human clusters. The latest cluster in Indonesia:
The latest confirmed case was that of a 16-year-old boy admitted to a state hospital in West Java's provincial capital Bandung on November 15.Stories like these, combined with complaints from health care workers about becoming ill after treating bird flu patients, are ominous. This is not the first cluster case in Indonesia. By my count it is the fourth with at least three deaths and a significant delay (greater than a week) between the first case and the last. In this case the surviving brother was hospitalized more than two weeks after the first two brothers became ill. They were diagnosed as having typhoid fever. The family's chickens are reported to have become ill and died two weeks before the first two kids became ill. Either we are looking at extremely long onset periods or we are looking at human to human transmission. The first confirmed H5N1 case in Jakarta was the first cluster. Three people died. Similar clusters have also been noted in Thailand and Vietnam.
Local radio reported that health officials on Sunday took blood and mucus samples from 24 of the boy's relatives and neighbours.
Two of his brothers, showing symptoms associated with bird flu, died of as yet undetermined causes a few weeks before he was taken to hospital, the report said.
Even WHO concedes that this latest cluster may indicate human to human transmission:
The WHO didn't assess the likelihood that the two deceased brothers had H5N1 or that the virus spread from person to person in the family. The statement said investigators found that chickens in the household had died in the 2 weeks before the deceased brothers got sick, and samples from the birds are being tested.Odd that samples from the birds are available but not from the two dead brothers! Other signficant developments in the last two weeks are that Beijing has set up some sort of clinical protocol in its hospitals (screening incoming patients with bird flu patients before admitting them to common patient areas) and several Asian countries have set up temperature screening for airports, etc.The doctors in the area seem to feel that human to human transmission is becoming more likely.
Most human cases of H5N1 have been attributed to exposure to sick poultry. Family clusters of cases raise the possibility of person-to-person transmission of the virus, which could signal an increase in the risk of a pandemic. Researchers reported recently that 15 family clusters occurred in Southeast Asia between January 2004 and July 2005. But only one family cluster, which occurred in Thailand in September 2004, has been classified as a probable result of person-to-person spread.
In the Americas we are still ramping up bird-testing programs. Maybe we should turn our attention to human testing programs. I doubt we are going to catch the first H5N1 cases in the US for several months. This is why I am watching the CDC's morbidity and mortality report. Click on mortality tables at the bottom of the screen and then you can see figures for pneumonia/flu deaths from selected US cities by week and year (for comparison purposes). You need to compare same city to same city for the previous two years, because average death rates will differ between cities.
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It's like the tide coming in- maybe imperceptable at first, but inevitable.
It seems we're still all gathered in the bottomland, unprepared.
It seems we're still all gathered in the bottomland, unprepared.
Uggh - after what happened on the Gulf Coast & NO I don't like the sound of "bottomland". I suppose you are being accurate, but here's hoping the virus becomes milder while adapting to humans and turns out to be less of an event than 1918.
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