Avian flu may spread via aerosol, droplets during poultry slaughtering
Slaughter of chickens infected with H5N1 avian influenza can produce airborne viruses that can infect birds and mammals, according to findings from a series of animal experiments done by a research team led by the US Department of Agriculture and the Centers for Disease Control and Prevention The investigators reported their finding on Oct 6 in Emerging Infectious Diseases.
Using lab-simulated processing of chickens asymptomatically infected with human- and avian-origin H5N1 viruses, the researchers identified both airborne infectious droplets and aerosols. However, they found fewer infectious particles in experiments involving ducks.
To assess if the airborne particles could infect flu-naive poultry and ferrets, they exposed the animals to the same airspace where the infected poultry were processed. They reported infections and deaths in chickens and ferrets housed next to chicken slaughtering, but not in ducks and ferrets kept in the same airspace with duck slaughtering.
The researchers said their findings support the hypothesis that highly pathogenic avian flu viruses can transmit among poultry and from poultry to humans during slaughter of infected poultry in homes or live-poultry markets.
Oct 6 Emerg Infect Dis study
H5N8 avian flu strikes more zoos and farms in South Africa
South Africa today reported several more highly pathogenic H5N8 avian flu outbreaks on commercial farms and in other settings, according to two notifications from the World Organization for Animal Health (OIE).
Seven more outbreaks were reported on farms, two of them involving backyard facilities, two at ostrich producers, and three on other commercial poultry farms. Six of the locations are in already hard-hit Western Cape province in the southwest, while one is in Free State province in the central part of the country.
The events began from Aug 30 to Sep 23, killing 102,522 of 428,136 susceptible birds. The surviving birds are slated for culling.
In a separate report, South Africa also reported five more H5N8 outbreaks involving other types of birds in other settings. Start dates range from Sep 6 to Sep 28.
Three occurred near Cape Town, two in hobby birds at backyard farms and one at a zoo housing a variety of domestic, exotic, and indigenous birds—200 different species. Another H5N8 detection occurred in a smaller number of birds at a zoo in Johannesburg. The fifth outbreak involved Egyptian geese found dead at a location in Gauteng province. The virus killed 26 of 558 susceptible birds, and 187 birds at the Cape Town zoo were culled to curb the spread of the virus.
Oct 9 OIE report on H5N8 at South African farms
Oct 9 OIE report on H5N8 in other South African birds
In other avian flu developments, Hungary reported 13 H5N8 outbreaks that occurred at the end of 2016 through Mar 20, 2017. The detections occurred across a wide part of the country, including the city of Budapest and six counties.
Most involved wild birds or captured wild geese, but one involved a pheasant breeding farm housing 1,800 birds. Outbreak response steps included culling, temporarily halting poultry transport, and enhanced surveillance.
Oct 9 OIE report on H5N8 in Hungary
No change in flu vaccine uptake after LAIV recommendation removed
A new study in Pediatrics shows that pediatric uptake of the flu vaccine did not change after the US Centers for Disease Control (CDC) recommended children not receive the live attenuated influenza vaccine (LAIV) for the 2016-17 flu season.
Researchers used Oregon's statewide immunization registry, the ALERT Immunization Information System, to compare vaccination rates during the 2015-16 season, when LAIV was recommended for children, and the 2016-17 season, when the CDC called for a return to injectable influenza vaccine (IIV) because of low effectiveness rates among LAIV users.
Children ages 3 to 10 were 1.03 times more likely to get an injectable influenza vaccine if they had received one in the previous season than those who had received an LAIV. Older children, ages 11 to 17, with previous IIV were 1.08 times more likely to return for an IIV. Overall, 53.1% of children with previous LAIV and 56.4% with a previous IIV returned for an IIV during the 2016017 season.
"For the great majority of parents, the likelihood of getting an influenza immunization for their children in the 2016-2017 season was only weakly dependent on whether they had previously chosen an LAIV or an IIV," the authors concluded.
Oct 6 Pediatrics study