WattAgNet: Asia, West Africa troubled by avian influenza

Written November 20, 2015 By Jackie Linden
The World Health Organization has put out an alert for a return of human cases of avian influenza in China as winter approaches, while new outbreaks have been reported in Asian and African poultry

Within the last ten days, there have been new reports about highly pathogenic avian influenza (HPAI) in 5 countries: Cambodia, Vietnam, South Korea, Nigeria and Cote d’Ivoire.

Asia battles H5 viruses
HPAI recently returned to South Korea with a vengeance, causing 12 new confirmed outbreaks between mid-September and the end of October, all on farms in the southwest of country. Ten were in South Jeolla province and two were in Gwangju city. All the premises had ducks and some also held chickens. Infected birds were identified through surveillance; none died but more than 144,000 birds have been destroyed as part of the stamping-out policy. The H5N8 variant of the virus was detected at each of the farms.

Meanwhile, Vietnam is battling to control the H5N1 and H5N6 subtypes of the HPAI virus in its poultry populations. There has been one outbreak of each type in backyard flocks in the last week; one involved 600 birds in Ca Mau province in the south of the country while the other was in Son La in the northwest and affected 326 birds. All the poultry in both outbreaks died or were destroyed.

There have been no reports of confirmed HPAI outbreaks in poultry in Taiwan. The Council of Agriculture has confirmed that a ban on the slaughter of live poultry at traditional markets has been implemented. The policy was proposed in 2006 in order to reduce the risks to public health but considerable resistance was encountered from some quarters. A program of intensive guidance and education was introduced to convince the public of the need to safeguard health following the experience of many human cases of avian influenza in China. 

H5N1 virus troubles West African poultry
Nigeria has reported its first outbreak on HPAI in more than a month in the state of Kano in the north of the country. A flock of 135 backyard layers was wiped out by the infection.

Following increased surveillance and testing at poultry markets in Abidjan, the veterinary authority in Cote d’Ivoire (Ivory Coast) has confirmed that 19 samples taken from 5,200 broilers and layers tested positive for the H5N1 virus during July of this year.

In South Africa, pre-slaughter monitoring of commercially reared ostriches revealed 12 out of 1,200 birds tested positive for an H7 low-pathogenic avian flu virus in Eastern Cape Province in August 2015. Recent cases have been in Western Cape Province.

H5N1, H7N9 viruses still threaten human health, warns WHO
The latest report from the World Health Organization (WHO) gives the total number of confirmed human cases for avian influenza A (H5N1) at 143, including 42 deaths. Of these, 136 cases and 39 deaths have been in Egypt, with the rest in China and Indonesia. This year already has more than twice as many cases as recent years. Since the outbreaks began in 2003, 844 people are confirmed to have been infected and 449 have died.

Two new confirmed human cases of avian influenza A (H7N9) virus infection have also been reported to the WHO from China in recent weeks, bringing the totals to 681 confirmed cases and at least 275 deaths. WHO states that this virus has continued to be detected in the animal population in multiple provinces across China this year, indicating that the virus persists in the poultry population. The organization warns that, if the pattern of human cases follows the trends seen in previous years, the number of human cases may rise over the coming months.