South Dakota and Maine report more high-path avian flu outbreaks
South Dakota reported three more highly pathogenic avian flu outbreaks on commercial poultry farms, while Maine reported another detection in a backyard flock, according to the latest updates from the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS).
The outbreaks in South Dakota raised the state's total to eight. The three new ones all occurred on turkey farms that have a total of 189,250 birds. Locations include two counties that have already reported similar outbreaks: Charles Mix and Hanson. The third event struck birds in Beadle County near Huron in the east central part of the state.
In Maine, the virus was found in a backyard flock for the eighth time, this time in a Cumberland County location that houses 150 mixed species of birds. Cumberland County is in the southern part of the state on the Atlantic coast.
The outbreaks are part of ongoing activity involving the Eurasian H5N1 strain, which has infected poultry in multiple parts of the world and has been implicated in one human infection, an individual who had very close contact with poultry. In the United States, the virus has led to the loss of about 13.4 million birds in 17 states since January.
USDA APHIS poultry outbreak page
WHO: Flu levels trend up again in parts of Northern Hemisphere
Flu levels, after peaking at the end of 2021, are creeping up again in some Northern Hemisphere countries, mainly due to the H3N2 strain, the World Health Organization (WHO) said in its latest global flu update, which covers the end of February and the first week of March.
In temperate parts of the Northern Hemisphere, flu activity rose or remained stable. For example, in North America, flu activity has increased over the past weeks, but is still at levels lower for this time of year for typical pre–COVID-19 pandemic seasons. Europe's levels also rose, mainly due to H3N2, while an increase in China was mainly from the influenza B Victoria lineage.
Tropical African countries reported ongoing flu spread in the eastern region from both H3N2 and influenza B. Meanwhile, in temperate Southern Hemisphere countries, flu remained low overall, but with some ongoing H3N2 detections in parts of South America.
Of the respiratory samples that tested positive for flu at national labs during the latest reporting period, 74.2% were influenza A and 25.8% were influenza B. Of the subtyped influenza A samples, 88% were H3N2. And of the characterized influenza B samples, all belonged to the Victoria lineage.
Mar 21 WHO global flu update