#18,087
While I was away from my desk for a few hours doing some badly needed pre-hurricane season prepping (4 new tires for the car), Helen Branswell tweeted a belated announcement from the USDA on the first detection of H5 in Alpacas.
The statement provides little information, other than these alpacas were from a premises where HPAI affected poultry were recently culled.Highly Pathogenic Avian Influenza (HPAI) H5N1 Detections in Alpacas
Last Modified: May 28, 2024
The National Veterinary Services Laboratories (NVSL) confirmed the detection of Highly Pathogenic Avian Influenza (HPAI) H5N1 in alpacas from a premises where HPAI-affected poultry were depopulated in May 2024. While this HPAI confirmation is not unexpected due to the previous HPAI detection on the premises, the high amount of virus in the environment, and co-mingling of multiple livestock species on-farm, it is the first HPAI detection in alpacas.
NVSL has confirmed that the viral genome sequence for these samples is the same sequence currently circulating in dairy cattle (B3.13), which is consistent with sequences from the depopulated poultry on this premises. (NVSL PCR confirmation was completed on May 16. APHIS reported the confirmation to the World Organisation for Animal Health and on the HPAI livestock website upon completion of additional gene sequencing, per APHIS policy for disease detections in new species.)
Alpacas belong the the family Camelidae, which includes 3 types of camels ( dromedary camels, Bactrian camels, wild Bactrian camels), and 4 lamoids (llama, alpaca, guanaco, and vicuña).
Camelidae - including both camels and alpacas - are known to be susceptible to MERS-CoV (see EID Journal: MERS-CoV Antibodies In Alpacas - Qatar), but less is known about their susceptibility to influenza A viruses.
A 2022 study, Influenza A Virus Infections in Dromedary Camels, Nigeria and Ethiopia, 2015–2017, reported:
We examined nasal swabs and serum samples acquired from dromedary camels in Nigeria and Ethiopia during 2015–2017 for evidence of influenza virus infection. We detected antibodies against influenza A(H1N1) and A(H3N2) viruses and isolated an influenza A(H1N1)pdm09–like virus from a camel in Nigeria. Influenza surveillance in dromedary camels is needed.
Last year Chinese scientists reported finding LPAI A/H7N9 in Mongolian camels back in 2020 (see ASM Journal: Characterization of an H7N9 Influenza Virus Isolated from Camels in Inner Mongolia, China), while in 2014 we saw an EID Journal report on the discovery of Equine H3N8 In Mongolian Bactrian Camel.
Immunization of Alpacas with H5N1 has been done in a laboratory setting (see Single-Cell Transcriptome Analysis of H5N1-HA-Stimulated Alpaca PBMCs) resulting in the animals mounting a robust immune response.
As far as I can tell, however, there have been no confirmed reports of natural infection of camelids with HPAI H5 until now. But, given H5's rapidly expanding host range, it is getting harder and harder to be surprised when a new species is added to the list..
The dangers of mixed-species farming, where poultry, pigs, cattle, mink, and yes . . . even alpacas, can readily exchange viruses are well known (see Study: Seroconversion of a Swine Herd in a Free-Range Rural Multi-Species Farm against HPAI H5N1 2.3.4.4b Clade Virus ).
But whether we've got the will, or the time, to change those practices is the $64 question.
