The World Health Organization (WHO) has recently reported the detection of the H5N1 avian influenza virus at high levels in the milk of infected cows. While it is still unclear how long the virus can persist in milk, experts are studying its longevity in the liquid. This comes after a person contracted bird flu after coming into contact with infected dairy cows earlier in the month, bringing concerns about the spread of the virus to new hosts.
In Texas, USA, this is the second case of A/H5N1 influenza in humans, with the first case involving a mammal infected with the virus. However, health officials have assured that there is no risk to commercial milk supply and that all milk from infected cows must be destroyed. Pasteurization can also kill the virus and maintain food safety through consumption of pasteurized dairy products.
Since its emergence in 1996, avian influenza A/H5N1 has caused numerous outbreaks in birds and more recently mammals as well. The virus has led to millions of deaths among poultry, wild birds, and various types of mammals worldwide. While cases in Europe or US typically feature mild symptoms, severe cases have been reported globally.
As of April 1st, 2021, WHO has recorded 463 deaths and 889 cases of H5N1 infection in humans across 23 countries globally, with a mortality rate of 52%. There have been no reports of human-to-human transmission of H5N1 but primarily through contact with infected animals. Nearly 20 vaccines are available for A/H5N1 influenza should a pandemic occur and adapt to specific virus strains.
