9 February 2006

 

Avian influenza H5N1 in Nigeria

The World Organisation for Animal Health (OIE) has been officially notified of an outbreak of avian influenza H5N1 amongst poultry in Nigeria [1].

The outbreak occurred at a poultry farm in the northern Nigerian state of Kaduna, where large numbers of chickens were being kept in battery cages. Samples were analysed at the OIE/Food and Agriculture Organization (FAO) reference laboratory in Padova, Italy where highly pathogenic H5N1 was confirmed.

Although poultry deaths have also been reported from neighbouring Kano State, the cause has not yet been identified [2].

Control measures have been implemented in the area, which include quarantine, control of animal movement within the country, and disinfection of the infected premises. A team of OIE/FAO experts are to be sent to the area to assess the situation and provide technical support. WHO is ready to respond to requests of support from Nigeria.

The confirmation of H5N1 in domestic birds in Nigeria marks the further geographical spread of the virus. Although evidence continues to indicate that the virus does not spread easily from birds to humans, WHO have acknowledged that careful monitoring of the situation is required [2].

The source of the outbreak in Nigeria has not yet been identified, but the country is known to lie in the flight path of migratory birds from central Asia. Full sequence information about the virus will be forthcoming, and will assist with identifying the origins of the outbreak.

Advice for travellers

There remain no restrictions for travel to countries that have been infected with avian influenza. Nevertheless, travellers should exercise precautions that have been previously posted [3]. In 2004, an estimated 98,000 persons travelled to Nigeria, the majority for the purpose of visiting friends and relatives [4].

Management of returning travellers or new entrants

The Health Protection Agency (HPA) Centre for Infections have revised the algorithm for the management of travellers or new entrants arriving from countries affected by avian influenza [5]. This algorithm now applies to persons arriving from Kaduna State, Nigeria.

The algorithm provides guidance on the recognition, investigation and management of persons with fever or history of fever and respiratory symptoms, and who have travelled to or lived in countries affected by avian influenza within 7 days of their arrival in the UK.

Physicians who see persons whom they suspect may have avian influenza, should evaluate them according to this HPA algorithm [5].

References

1. World Organisation for Animal Health. Avian influenza outbreak in Nigeria. 8 February 2006. [cited 9 February 2006] Available at: http://www.oie.int/eng/press/en_060208.htm

2. World Health Organization. Avian influenza - situation (birds) in Nigeria. 8 February 2006. [cited 9 February 2006] Available at: http://www.who.int/csr/don/2006_02_08/en/index.html

3. NaTHNaC. Avian influenza - advice for travellers to affected areas. 4 November 2005. [cited 9 February 2006] Available at: http://www.NaTHNaC.org/pro/clinical_updates/aviani

nfluenza_advice_041105.htm

4. Office for National Statistics (ONS). International Passenger Survey 2004. London: ONS; 2005.

5. Health Protection Agency. Algorithm for the management of returning travellers from countries affected by avian influenza presenting with a febrile illness: recognition, investigation and initial management. 8 February 2006. [cited 9 February 2006] Available at: http://www.hpa.org.uk/web/HPAweb&HPA

webStandard/HPAweb_C/1195733851442