UPDATED 0630 hrs 10/31 (See bottom of page)
# 5931
Ida at BFIC has a brief story (that I should also note has been picked up by the newshounds at The Flu Wiki and at FluTrackers) on the hospitalization and isolation of a mother and child in Bali suspected of H5N1 infection.
Denpasar, Bali ::: Sanglah hospital treats 2 bird flu suspects
Posted by Ida on October 30, 2011
Denpasar – A mother (42-year-old) and her daughter (10-year-old), residents of Banjar Pande, Abiansemal, Badung, treated intensively as bird flu suspect patients in Sanglah hospital. They were referred from Kapal hospital, Friday (28/10).
Spokesman of the hospital said the patients complained fever, and coughing. There is no history of contact with any birds. Hospital is still waiting for laboratory test for bird flu H5N1 diagnosis of both patients.
Patients are currently in stable condition. The fever and cough have stopped.
During 2011, Sanglah hospital has treated 20 bird flu suspect patients, and 2 of them tested positive H5N1 and died.
As noted in the article, of 20 suspected cases in Bali during the month of October, only 2 tested positive for the bird flu virus. Both of those died (see WHO: Indonesian Bird Flu Update #7).
A third case – the mother of the two children who – also died a week later, but we’ve not seen any confirmatory test results.
While unproven, H5N1 is strongly suspected.
As for the others who tested negative, the assumption is that they probably had some other illness (although it is possible – given well documented sensitivity issues with the tests - that some false-negatives may have been returned by the lab).
This is a pattern we’ve seen all along, both in Indonesia and in Egypt, where only a fraction of those suspected of having the H5N1 virus ever test positive for the disease.
Given the potential for spreading in the populace, it is only prudent to suspect H5N1 – and take the appropriate steps of isolation and testing of patients – in those regions where the virus is endemic.
There are plenty of other viral pathogens co-circulating in these regions (ie. seasonal influenza, dengue, RSV, etc.) capable of producing `bird flu symptoms’, hence, we tend to see a great many `suspected cases’.
Ideally, those who tested negative would undergo serological retesting 4 weeks later to see if they’d developed H5N1 specific antibodies, but if that is being done in Indonesia, it isn’t being advertised.
In November of last year we saw a proposal to do just that sort of seroprevalence testing in Egypt (see A Prospective Avian Influenza Transmission Study For Egypt).
And last month, we saw a study that reported the results of this kind of serological testing conducted in a rural village in Thailand in 2008 (see Bangladesh To Share H9N2 Bird Flu Virus).
Out of 800 villagers tested, the authors found 4.7% were seropositive for the Hong Kong H9N2 avian strain, 5.6% had antibodies to A/Thailand/676/2005 H5N1 bird flu, and 3.5% were shown to be seropositive to A/Thailand/384/2006 H5N1 .
Suggesting that mild or asymptomatic spread of these viruses may be going undetected in parts of Asia.
The simple fact that follow-up testing like this is the exception, and not the rule, is one of the reasons why there remain so many unanswered questions about how the virus transmits in humans.
But in many regions of the world where the virus is endemic (primarily Asia and the Middle East), a lack of political will, societal and religious customs, and economic barriers make this sort of testing extraordinarily difficult.
Although we continue to see isolated human infections around the world, and the virus continues to evolve (see H5N1: An Increasingly Complex Family Tree), for now H5N1 is primarily a threat to poultry.
The concern, of course, is that over time that could change.
And so the world remains at Pre-pandemic Phase III on the H5N1 virus, and we continue to watch for signs that the virus is adapting better to humans.
Updated 10/31/11: Ida at BFIC has a report from the Bali Post indicating that both patients tested negative, and have been discharged (see Denpasar, Bali ::: Two suspects test negative). A third patient – a 6 year-old with the initials JS – has been admitted for testing and treatment of a possible bird flu infection.
