DJ A NL study did find out carnivores eating H5N1-infected birds had the H5N1-virus in their brain..One question I have is does that mean H5N1 now may be in rats, cats, mice their brains as well ? Did we miss a lot of spread by only looking at respitory system for H5N1 in carnivores ? (If that is what "we" did most of the time ?)

The study [url]https://www.mdpi.com/2076-0817/12/2/168[/url] or https://www.mdpi.com/2076-0817/12/2/168 - https://www.mdpi.com/2076-0817/12/2/168 ;

Abstract

-

3. Results

3.1. Virological Analysis of Infected Carnivores

During the period December 2021–February 2022, 21 wild carnivores suspected of HPAI H5N1 infection based on neurological signs or evidence of viral infection in post-mortem sections were submitted for testing. Of these, 14 animals tested positive for influenza A virus using the M-PCR. Three red foxes (Vulpes vulpes) were analyzed in a previous study [ https://www.mdpi.com/2076-0817/12/2/168#B8-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700;" title=" - 8 ]. The current study describes the analysis of the 11 other carnivores: red fox (n = 6), polecat (Mustela putorius) (n = 3), badger (Meles meles) (n = 1), and otter (Lutra lutra) (n = 1) ( https://www.mdpi.com/2076-0817/12/2/168#table_body_display_pathogens-12-00168-t001" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; outline: none; cursor: pointer; width: 200px; margin: 0px auto; - Table 1 ). The locations where the infected carnivores were found were dispersed over the Netherlands ( https://www.mdpi.com/2076-0817/12/2/168#fig_body_display_pathogens-12-00168-f001" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; outline: none; cursor: pointer; max-width: 400px; margin: 0px auto; - Figure 1 ) and the cases did not cluster geographically. When examined, overall viral loads in brain tissues were higher than those in the swabs of the throat and intestinal tract. All viruses detected were of the subtype HPAI H5N1. Virus isolation was performed in eight animals, showing the presence of the infectious virus in five animals ( https://www.mdpi.com/2076-0817/12/2/168#app1-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; - Table S1 ).

https://www.mdpi.com/2076-0817/12/2/168#fig_body_display_pathogens-12-00168-f001" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; outline: none; cursor: pointer; max-width: 400px; margin: 0px auto; background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABkAAAAyCAYAAACpgnCWAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAlpJREFUeNpiNDY2ZgACaSDuBWIbKJtS8BSIjwBxMYjNAiTUgfgYEAsxUA+AHBoOxK5AbMsEJFqobAEyAJnbwgS1jZbAFWQJP40t4WFioANgwSYYEBDAUFRUxMDFxYUhZ2JiAqYPHDjAwMPDg1OeoCUlJSUMHBwcDF+/fmX4//8/bXwCsgAE7O3tcWp0cHAA+2Tq1KkM2traeC0hO04EBQUZpk2bBrbg48eP1LcEZMGMGTMYtLS0GN69e8dQWFhIenARAn19fQzKysoMr169YkhPT2f48OED9X3S29vLcOvWLbAFjx8/Zvj8+TM4VWFLWWT75MqVKwxRUVFEq6daZjxz5gwY09QSuviE5NT148cPcIY8ePAgUTmekZERro9oS0CpB5T2ubm5iXbtt2/fGPr7+7E7Alj9/h8WcQKy5CON7fgCsmQfjS3ZDbKkBojf0cgCkLk1IEuuAbEeEK8B4hdUMvwF1DyQuddYJC1qYBJ/oZgaAMWs0cbdaOMOAdys5BlSgnQZODkwpX1zNoDpFd3eDNycrDjlCVqSFqLHwM7GzPDtxx/aNe5AFoBAeMkWnBojSreCfdKUY8WgJi9Im1KYn4edoTnXGmzB56+/qG8JyILWPGsGVTkBhg+ffzI0zzxB/cZdbbo5g7wUH8PbDz8YKiceZvj05Rf1LZm99jJDdqQBQ/ucUwzPX3/FmaoosuTmg/cMee376V/9bp4SAMYjsHH389dfcIZc2eNDUuMOpI9oS0CpJzlQh4GLg/h08R1YBM1df4V4S3YefQDGo4270cYdRY07gAADAEjYxGK8ZXdOAAAAAElFTkSuQmCC") 0px 0px no-repeat; vertical-align: middle; display: inline-block; width: 25px; height: 25px; position: absolute; top: 0px; right: -8px; -

Figure 1. Map of the locations were HPAI H5N1 infected carnivores were found during the 2021–2022 epizootic in the Netherlands. The infected carnivores analyzed in this study are marked in orange, and numbers are corresponding to  https://www.mdpi.com/2076-0817/12/2/168#table_body_display_pathogens-12-00168-t001" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; outline: none; cursor: pointer; width: 200px; margin: 0px auto; - Table 1 . The infected mammals analyzed in previous studies [ https://www.mdpi.com/2076-0817/12/2/168#B8-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700;" title=" - 8 ] are depicted in grey. The map was generated using the R software package tmap [ https://www.mdpi.com/2076-0817/12/2/168#B24-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700;" title=" - 24 ].

DJ discussion and results;

4. Discussion

-

Conclusions

DJ...in my non expert view this study is very alarming...H5N1 is spreading from infected birds into carnivores...very likely on a large scale. There are mutations enabling better mammal-to-mammal spread...that such spread so far has not been detected does not mean that it is not happening....

Finally, many of the wild carnivores were infested with lung parasites [ https://www.mdpi.com/2076-0817/12/2/168#B33-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; font-family: Arial, Arial, Helvetica, sans-serif; font-size: 13.2px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: justify; text-indent: 26.4px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255);" title=" - 33 ]. Especially in red foxes, the presence of A. vasorum larvae in the lungs was a common finding [ https://www.mdpi.com/2076-0817/12/2/168#B34-pathogens-12-00168" style="box-sizing: border-box; color: rgb(79, 86, 113); line-height: inherit; text-decoration: none; max-height: 1e+06px; font-weight: 700; font-family: Arial, Arial, Helvetica, sans-serif; font-size: 13.2px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: justify; text-indent: 26.4px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255);" title=" - 34 ] and may have overshadowed changes due to HPAI lung pathology. Furthermore, the lung pathology and the clinical relevance of these parasites is variable in wildlife and it is unclear if these co-infections influenced susceptibility to HPAI. Besides these limitations, our results can be used to improve HPAI wildlife surveillance.

Coinfections may complicate detecting H5N1 spread in mammals...

Minks did show high spread from mink to mink of H5N1..."mink-like animals" in the wild could become the missing gap between H5N1 spread in birds and H2H/ spread in humans...