# 5065
Timing, they say, is everything.
And so it is fitting that on a day when we learn of an H5N1 positive Hong Kong resident - who reportedly visited live bird markets on the mainland - we get this survey of H5N1 environmental contamination at LBMs (Live Bird Markets) in Indonesia.
The `big news’ here is that traces of the H5N1 virus were detected (using real-time reverse transcription–PCR and virus isolation) in nearly half (47%) of the 83 markets tested.
You should know, however, that RT-PCR testing can detect non-viable virus particles. And so just because the virus was detected, that doesn’t necessarily mean the virus was capable of infecting a new host.
Virus isolation, while less well suited for testing environment samples, only detects viable viral contamination.
As you might expect, the percentage of positives by virus isolation was considerably lower than that returned by RT-PCR.
Of the 280 positive samples by RT-PCR, only 13 (4.6%) were positive by virus isolation (Probably a low-ball number, given the sensitivity of the test).
These numbers do give us an idea of just how prevalent H5N1 is in domestic poultry in Indonesia, and argue compellingly for better sanitation procedures in live markets.
I suppose the solace we can take from all this is that – despite numerous contaminated live bird markets in Indonesia - we haven’t seen a huge number of human infections.
Given the amount of human contact with infected birds and contaminated environments, this strongly suggests that the virus remains poorly adapted to human physiology and difficult to contract.
This study is published ahead of print in today’s EID Journal.
Volume 16, Number 12–December 2010
Research
Environmental Sampling for Avian Influenza Virus A (H5N1) in Live-Bird Markets, Indonesia
Indriani R, Samaan G, Gultom A, Loth L, Indryani S, Adjid R, et al. Environmental sampling for avian influenza virus A (H5N1) in live-bird markets, Indonesia. Emerg Infect Dis [serial on the Internet]. 2010 Dec [date cited]. http://www.cdc.gov/EID/content/16/12/1889.htm
DOI: 10.3201/eid1612.100402
Abstract
To identify environmental sites commonly contaminated by avian influenza virus A (H5N1) in live-bird markets in Indonesia, we investigated 83 markets in 3 provinces in Indonesia.
At each market, samples were collected from up to 27 poultry-related sites to assess the extent of contamination. Samples were tested by using real-time reverse transcription–PCR and virus isolation. A questionnaire was used to ascertain types of birds in the market, general infrastructure, and work practices.
Thirty-nine (47%) markets showed contamination with avian influenza virus in >1 of the sites sampled. Risk factors were slaughtering birds in the market and being located in West Java province.
Protective factors included daily removal of waste and zoning that segregated poultry-related work flow areas. These results can aid in the design of evidence-based programs concerning environmental sanitation, food safety, and surveillance to reduce the risk for avian influenza virus A (H5N1) transmission in live-bird markets.
Follow the link to read details about the methods of sample collecting,testing and the results.
