Photo Credit – FAO
The big news today coming out of China, beyond the five new cases and 2 deaths (see Xinhua: Updating The H7N9 Case Counts In Shanghai), has been the detection of the H7N9 virus in pigeons tested at a live-bird market.
We are also seeing reports that at least one contact of a confirmed (fatal) case has now developed symptoms, and is in isolation.
The following update (h/t Eric) from Xinhua News indicates that extensive culling of poultry has now been ordered. The mention of a `contact’ in isolation may be significant, as it is at least suggestive of H2H transmission, although we have no laboratory confirmation of infection.
English.news.cn 2013-04-05 01:30:22
SHANGHAI, April 5 (Xinhua) -- Authorities in Shanghai on Thursday closed a live poultry trading zone in an agricultural products market and began slaughtering all birds there after detecting H7N9 bird flu virus from samples of pigeon from the market.
Meanwhile, a person who had close contact with a dead H7N9 bird flu patient in Shanghai has been under treatment in quarantine after developing symptoms of fever, running nose and throat itching, the Shanghai Municipal Health and Family Planning Commission said late Thursday.
China's Ministry of Agriculture said Thursday it found the H7N9 virus from pigeon samples collected at the Huhuai wholesale agricultural products market in Songjiang district of Shanghai.
After gene sequence analysis, the national avian flu reference laboratory concluded that the strain of the H7N9 virus found on pigeons was highly congenetic with those found on persons infected with H7N9 virus, the ministry said.
The Shanghai municipal agricultural commission said it has ordered proper disposal of the culled birds, their excrements and contaminated food as well as disinfection of the market and vehicles that carried them and other things that have contacts with them.
The commission will also investigate and track where the pigeons came from, it said.
Meanwhile, the agency ordered the closure of the live poultry trading areas of two markets in Minhang district after samples there were found with H7 bird flu virus.
You may recall that it was the controversial decision by Margaret Chan to cull all of the poultry in Hong Kong in 1997 that was credited with eventually stopping the first outbreak of H5N1 in its tracks.
In that case, the H5N1 bird flu virus was more geographically contained. We currently have reports of H7N9 cases from multiple cities across three provinces, which will make culling operations more difficult.
It is unknown at this time where or how the pigeons that tested positive in the Shanghai market contracted the virus, or how many of the human infections are due to poultry exposure.
Whether this virus has found a home in the wild bird population, or other host animals (like pigs, rodents, or other small mammals) is likewise an open question.
Until the actual sources and modes of transmission of this virus are better understood, containment and eradication strategies such as culling may only prove partially successful.