After the recent outbreak of the H5N1 strain of Avian Influenza and the subsequent allegations that migratory birds are responsible for the spread of the disease to local poultry farms WWF Pakistan is concerned that such statements could have serious repercussion against wild bird populations and their habitats.

Since the recent outbreak in the Sindh, WWF Pakistan has been in close contact with the BirdLife International that has already carried out significant research on the role of wild birds, including migratory species in the spread of HPAI H5N1. WWF Pakistan would like to highlight some of the scientific facts that support the case that though there is some evidence to back the case that migratory wild-birds can spread the H5N1 virus, they are not the main source of the virus nor are they solely responsible for the spread of H5N1. There is no information available on the ability of an infected bird capable of migration therefore migratory birds cannot be held responsible.

• The FAO collected samples from between 300,000 to 350,000 wild-birds across the world. None of these were found H5N1 positive. Likewise, sampling of 5000 water-birds after the outbreak in Nigeria during 2006 found no traces of the virus (AIWEB website). In fact despite increased sampling around the world, no fully documented healthy migratory wild birds have tested positive for H5N1.

• Mapping of the outbreaks across the world has shown that they follow trade routes of poultry rather than migratory flyway of wild-birds. After a comprehensive critical review of recent scientific literature it has been concluded that that poultry trade, rather than bird migration, is the main mechanism of global dispersal of the virus. 

• The widespread illegal trade in cage birds has transported H5N1 infected birds over large distances. The most likely source of infection in captive birds is at live animal ‘wet’ markets in Asia, where domestic and wild-caught birds are kept in close proximity, posing a high-risk of cross-contamination. There is a healthy bird trade in the cities of Pakistan and as of yet there has been no study to determine whether this is a factor in the spread of the disease or not.

• Avian influenza viruses are readily transmitted from farm to farm by the movement of live birds, people (especially when shoes and other clothing are contaminated), and contaminated vehicles, equipment, feed, and cages. Highly pathogenic viruses can survive for long periods in the environment, especially when temperatures are low. For example, the highly pathogenic H5N1 virus can survive in bird faeces for at least 35 days at low temperature (4oC). At a much higher temperature (37oC), H5N1 viruses have been shown to survive, in faecal samples, for six days (WHO)

 
In conclusion it is unlikely that wild birds play a major role in spreading avian influenza. The total number of wild birds affected has so far been small and although billions of wild birds cross continents regularly during their migrations they do not seem to have a significant impact on spreading the virus on a large scale. In fact, it seems that with the degradation and destruction of lake and wetlands, migratory birds are forced to feed and live in areas populated by domestic poultry (and humans), putting the wild-birds at risk of infection.

Keeping this information in mind WWF Pakistan calls for the following actions and approaches to be adopted in the best interest of the environment and the poultry industry that is being directly affected:

• Media should play a responsible role in the dissemination of information based on facts and scientific research, especially to that pertaining to the role of wild migratory birds in spreading the H5N1 disease;

• Relevant academia should work alongside the concerned government departments to test for the H5N1 strain in wild birds and caged birds traded in the major cities of Pakistan;
• Relevant authorities should establish a mechanism to monitor any suspicious mortality of bird species in the wild;
• All government departments, private and public sectors should share information and data related to the outbreak of Avian Influenza freely and transparently;
• Help in mobilisation of resources of surveillance.
• Vaccination of birds housed in zoos.
• Humane culling of birds should be adopted in case of an outbreak and proper disposal.
• It should be made mandatory for poultry to have a tracking number, because once they are in shops, they cannot be tracked back to a poultry farm.
• Strict hygiene and bio-security measures at poultry farms and zoos are needed. People and vehicle coming into these places should be disinfected, caretakers should meticulous clean utensils and of course their hands and feet. The main risks of virus entry are: bringing in live birds, bringing in objects such as animal and bird cages or feed that has been contaminated by birds, bringing in dirty (faeces contaminated) footware, vehicles, clothing, that has recently passed through animal markets or chicken or duck farms.

In conclusion, WWF Pakistan does not support any mass culling of wild-birds or the destruction of their habitats.  On the contrary WWF Pakistan advises that wild birds and there associated habitats are left undisturbed so that wild birds can inhabit them in safety and do not seek out refuges near human settlements, and therefore not coming into contact with the virus.

Source of information:
www.birdlife.org
www.aiweb.info/document.aspx?DocID=296
http://www.who.int/mediacentre/factsheets/avian_influenza/en/
http://www.fao.org/docs/eims/upload/191072/EW_HPAIwildbird_aug05.pdf

Dr. Ghulam Akbar, Director, Indus For All Programme, gakbar@wwf.org.pk
Uzma Khan, Manager Conservation Programme, ukhan@wwf.org.pk
Samman Ehsan, Senior Communication Executive, publications@wwf.org.pk