Confirmed H5N1 Clusters in Pakistan
Recombinomics Commentary
December 15, 2007
The Health Ministry said it had tested several patients and others they had been in contact with in late October. The results for six people from the Abbottabad and Mansehra districts of North West Frontier Province were positive, it said in a statement.
"Five of them have fully recovered. One of the confirmed cases died in hospital, while his brother who could not be tested has also died," the Health Ministry said in a statement.
The above comments indicate the Health Ministry has confirmed early media reports describing infections of cullers and contacts stemming from two H5N1 poultry outbreaks in October. Moreover, media reports indicate WHO has acknowledged the positive lab confirmations, and results from a second round of confirmatory test on Tuesday. Although a sample from one of the deceased brothers appears to be missing, there is little doubt that seven people were H5N1 infected and two died.
It is also clear that it has been more than six weeks since the culling was completed, which apparently was conducted between October 21-23, and it has been over six weeks since serum samples were collected in October. It is unclear why these data are being announced in the middle of December along with a hospital alert.
Media reports strongly suggest there were two familial clusters involving a veterinarian who was the index case for one cluster of four brothers, and a laborer who was the index case for another cluster, which included his daughter. The disease onset dates are still missing for these seven cases, and the dates of the death of the two brothers are not firm, although one report did indicate hey died on November 19 and 29.
The circumstances surrounding the brother that returned to the United States also remains cloudy. Rumors have circulated that he returned to New York and tested negative, but no agency in the United States has issue a statement on the circumstances surrounding this brother’s trip to and from Pakistan.
The reporting delays and lack of detail remain causes of concern, as is the large number of infections in cases and contacts. These numbers are similar to the initial outbreak in Turkey two years ago, but the human-to-human transmission appears to be more striking because several of the contacts appear to not have poultry contacts, and the transmission change may represent human-to-human-to-human, which would match the longest H5N1 reported to date.
Moreover, the sub-clade in Pakistan is likely to be similar to the Uva Lake strain, which has been widely reported in Europe and the Middle East. The most recent report in Europe is in eastern Germany, which is near other recent outbreaks in Poland. Similarly, Saudi Arabia and Egypt have ongoing poultry outbreaks creating additional concerns based on past human cases in Egypt, and the Haaj beginning in Saudi Arabia.
More detail on the cases in Pakistan, including sequences from poultry and patients would be useful,
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