Symptomatic H5N1 Cullers in Chirang Assam Raise Concerns

Recombinomics Commentary 15:24
December 14, 2008


Four people, including two veterinary officials involved in the culling operations, were put under surveillance and blood samples collected after they complained of fever and cold in western Chirang district of Assam.

“We have sent blood samples of four people to a laboratory in New Delhi to ascertain if they had contracted the bird flu virus.

The above comments on four symptomatic cullers in Chirang raise additional concerns regarding H5N1 transmission to people in Assam, India. A recent Ministry of Health report details the status of URI patients which includes and increase from 60 to 90 in URI patients in Barpeta as well as and increase from 14 to 70 hospitalized patients in the Rampur area (see updated map).

Although bird flu has been said to have been excluded in these patients, they remain under observation and the criteria for exclusion, beyond a lack of link with poultry, remains unclear.

The cullers in Chirang obviously have a link, but detail on their symptoms and testing also remain unclear.

Last season India only reported H5N1 in poultry, which is also true for earlier outbreaks. However, piles of dead crows were filmed adjacent to dead poultry in West Bengal while jackals and dogs died after eating dead or dying poultry in Tripura.

Moreover, Bangladesh confirmed H5N1 in dead crows as well as a child in a Dhaka slum, who recovered. The human case was confirmed in routine testing of samples long after the patient recovered, raising concerns of mild cases linked to the H5N1 outbreaks in Bangladesh and India. It is also unclear if the child in Bangladesh developed pneumonia, which appears to be one of the criteria used in India.

The detail on testing of suspect human cases in India remains obscure. Poultry positives appear to be classified in limited and delayed testing in Bhopal using a rapid test, which is not very sensitive. Moreover, all of the initial positives in Assam were on tissue samples from dead birds, raising additional concerns regarding sensitivity of tests on serum or swabs (such as the "blood test" cited above).

Thus, the frequency and sensitivity of testing in India remains suspect, as the number of suspect patients continues to increase.