Ed HillAug 4, 2023

1/ Three papers in latest #Eurosurveillance issue (03 Aug 2023) are on outbreaks of highly pathogenic #AvianInfluenza A(#H5N1) virus infection in animals. #HPAI

"Highly pathogenic avian influenza A(H5N1) virus infection on multiple fur farms in the South & Central Ostrobothnia regions of Finland, July 2023"

▶️ First reported on 14 July, an outbreak of avian influenza among farmed foxes, minks & raccoon dogs

▶️ Up to 27 July, animals on 20 farms have been affected

🔗: https://doi.org/10.2807/1560-7917.ES.2023.28.31.2300400

Eurosurveillance | Highly pathogenic avian influenza A(H5N1) virus infection on multiple fur farms in the South and Central Ostrobothnia regions of Finland, July 2023

Since mid-July 2023, an outbreak caused by highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b genotype BB is ongoing among farmed animals in South and Central Ostrobothnia, Finland. Infections in foxes, American minks and raccoon dogs have been confirmed on 20 farms. Genetic analysis suggests introductions from wild birds scavenging for food in farm areas. Investigations point to direct transmission between animals. While no human infections have been detected, control measures are being implemented to limit spread and human exposure.

Show threadChristian TestaAug 4, 2023

@EdMHill it’s interesting that attention was garnered here, it seems, as a result of an informal excess deaths framework (e.g., noting that mortality was rapidly increasing) applied to livestock (in this case, the foxes, minks, raccoon dogs, etc).

I only skimmed the beginning of the article, but I was wondering — do we have a sense of if there is mammal to mammal transmission happening in this or related outbreaks?

Show threadEd HillAug 4, 2023
@ctesta My commentary on what the authors have presented for this outbreak event is there being plausible support for mammal to mammal transmission having occurred , but the data/evidence is not sufficient to attribute high confidence to exact transmission mechanisms.
Show threadEd Hill

@ctesta Some quotes from the study (plus image from relevant section of the study)

▶️ "Phylogenetic analyses further suggest that several introductions from birds to the fur animals may have taken place but are also consistent with possible transmission among the fur animals themselves and potentially even between species"

▶️ "The exact mechanism of the transmission within and between farms is, however, not yet known."

Aug 4, 2023 at 12:39pmWeb
Show threadChristian TestaAug 5, 2023
@EdMHill thanks for the update! much appreciated