Clusters in Pakistan Raise Pandemic Concerns
Recombinomics Commentary
December 14, 2007
The men died at least 10 days ago, but the Pakistani government did not disclose their deaths and has refused to confirm test results of whether they succumbed to the H5N1 avian influenza virus.
The victims, whose names were not released, were in the 20s and 30s and worked together on a chicken farm in Manshera, North-West Frontier Province, and had direct contact with birds, said Siddiqur Rahman, chief medical officer at the Khyber Teaching Hospital in Peshawar, the provincial capital.
He said the men were brought into the hospital in critical condition "about 10 days ago" suffering from pneumonia and died soon after.
"After having suspicions that the deaths were caused by bird flu, we informed the Health Ministry, which took blood samples and sent them to the government laboratory in Islamabad," Rahman told DPA.
Mazhar Barjis, chief public health officer at the National Institute of Health in Islamabad, which houses the laboratory, said testing of the samples was underway.
The above comments represent another media report suggesting the brothers who were said to die this month are distinct from the bothers said to have died on November 19 and November 29. The brothers who died last month were part of a four member familial cluster. The index case for that cluster was a veterinarian who participated in a cull of poultry from an outbreak in October. He tested positive as did a surviving brother, while two other brothers died with bird flu symptoms and samples were not collected.
In October, 40 human samples were tested and four were positive. Included was another culler, whose daughter has been hospitalized along with another person. Thus, the number of hospitalized, H5N1 positive, or fatal cases linked to the October outbreak may have involved as many as 8 patients, including at least two clusters.
The fatal cases from this month were said to have poultry contacts and are stll being tested. Although it is possible that the two sets of fatally infected brothers are the same, the media reports are quite different in time of death and prior linkages to poultry.
However, regardless of the number of reported clusters, the disclosure of the cases has been delayed. Moreover, the hospital alert raises concerns that the number of cases is markedly higher than the numbers being reported. Usually, H5N1 infections via contact with birds are uncommon, and cullers are rarely infected. Moreover, the four member H5N1 cluster is among the largest reported to date.
These data support a more efficient transmission of the H5N1 in Pakistan. No sequences from earlier isolates in Pakistan have been released, although sequences from Afghanistan and India isolates from 2006 show a close relationship, and these sequences are also related to H5N1 sequences released from isolates in Germany and Russia. Moreover, those sequences are said to be related to sequences in Kuwait, France, Czech Republic, and England. Moreover, the timing and location of outbreaks in Romania, Poland, Rostov, and Saudi Arabia suggest these outbreaks may also be related.
The WHO has not commented on the current situation in Pakistan or on the sequences from earlier poultry H5N1 outbreaks. This silence does not inspire confidence, since these outbreaks appear to link back to October.
Media Links
Recombinomics Presentations
Recombinomics Publications
Recombinomics Paper at Nature Precedings