Highly Pathogenic Avian Influenza (HPAI) H5N1

Avian influenza also known as the Bird Flu refers to the influenza viruses that occurs naturally among birds. Most of these influenza viruses cause mild or no infection in birds, however, the range of symptoms may vary depending on the strain. The severity of the disease in poultry determines whether the virus is "low pathogenic" LPAI or "highly pathogenic". 

HPAI stands for Highly Pathogenic Avian Influenza and H5N1 refers to the viral sub-type. It resides in the intestines of wild birds and is highly contagious among the bird population. This strain is of great concern because it can cause widespread disease and death among some species, especially domestic birds such as chickens and turkeys. 

The HPAI H5N1 is widespread in wild birds worldwide and has also been detected in many backyard poultry flocks.

It has been an ongoing multi-state outbreak in dairy cattle. It currently (as of November 5, 2024) is in a total of 15 states with 442 confirmed cases. (California, Michigan, New Mexico, Colorado, Minnesota, Idaho, Oklahoma, Iowa, Texas, South Dakota, Kansas, North Carolina, Ohio, and Utah)

The HPAI H5N1 has also infected some mammals believed to have eaten infected birds. These include seals, bears, foxes, skunks; farmed mink; stray or domestic animals, such as cats and dogs; and zoo animals, such as tigers and leopards. On October 30, it has been reported to be in a pig in Oregon.

This is a novel virus, and the world population has no immunity to it. The death rate of Covid-19 at its height was .0012[1](1.2%) The death rate of HPAI H5N1 globally from January 1, 2003, to July 19, 2024, is 52%. 463 deaths of 896 reported cases.[2]

[1] “Assessing the Impact of the Covid-19 Pandemic on US Mortality”, Andrew C Stokes, PhD, et al, National Institutes of Health (NIH) (gov). Revised March 22, 2022, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7480051/ Accessed October 11, 2024

[2] “Human Infection with Avian Influenza A(H5) Viruses,” World Health Organization, https://cdn.who.int/media/docs/default-source/wpro---documents/emergency/surveillance/avian-influenza/ai_20241004.pdf?sfvrsn=5f006f99_142, October 4, 2024, Accessed October 11, 2024.