Avian flu and risk of contagion from milking equipment, the discovery

Workers on dairy farms where the highly pathogenic avian influenza (H5N1) virus is circulating “are at risk of infection“not only through direct contact with unpasteurized milk, produced by sick cows, but also”through contaminated surfaces during the milking process“. On this point, Valerie Le Sage and colleagues from the Vaccine Research Center at the University of Pittsburgh, in the USA, have collected “convincing evidence”. The study is published in ‘Emerging Infectious Disease’, a journal of the Centers for Disease Control and Prevention (CDC).

In light of the Hpai-H5N1 virus epidemic in dairy cows in several American states, the authors tested the persistence of avian influenza A(H5N1) and human influenza A(H1N1) viruses in laboratory experiments. on the tools used for milking. The test found that “both remain infectious on milking equipment materials for several hours”, even more than three. Results that highlight precisely “the risk of transmission of the H5N1 virus to humans from contaminated surfaces during milking“. And beyond the intensity of the symptoms – which in the 4 human cases officially confirmed so far by the CDC as linked to the avian flu epidemic in cattle have been mild, almost always confined to the eyes – the fear is that “the increase in human infections by the H5 virus could allow the viruses themselves to adapt to humans, evolving within their organism, becoming capable of being transmitted from one person to another”.

Hence the recommendation: “To reduce the spread of the H5N1 virus from dairy cows to humans – scientists warn – farms should implement the use of personal protective equipment such as masksvisors and other eye protection among workers during milking.” An additional concern is about particular rubber liners used in the milking process: “Contaminated ones could be responsible for the animal-to-animal spread of the virus, observed in dairy cattle. Sanitizing the liners after milking each cow – the researchers suggest – could reduce the spread of the virus among animals and help curb the current epidemic.”