Wastewater testing finds H5N1 avian flu in 9 Texas cities

Researchers who sequenced viruses from wastewater samples from 10 Texas cities discovered H5N1 avian flu virus in 9 of them, generally at ranges that rivaled seasonal flu.

In different developments, the Facilities for Illness Management and Prevention (CDC) in updates on its response to H5N1 outbreaks in cattle mentioned experiments in ferrets started final week.

Findings tilt towards animal supply 

A group from Baylor Faculty of Drugs and the College of Texas Well being Sciences Middle detailed their whole-virome sequencing findings in a brand new preprint examine.

With many questions nonetheless unanswered about how the virus is spreading in dairy cows and the way extensively the virus is circulating, scientists are more and more eyeing wastewater sampling as a key surveillance device.

The group reported H5N1 in wastewater from March 4 to April 25. They mentioned 19 of 23 monitored wastewater websites had at the least one detection occasion and that, over time, H5N1 grew to become the dominant serotype. They didn’t title the ten cities they monitored, and the findings have but to be peer-reviewed. 

On X, Mike Tisza, PhD, the primary writer of the examine and assistant professor of virology and microbiology at Baylor, mentioned it is nonetheless not clear the place the viruses got here from, however the proof tilts towards an animal supply, as a result of the researchers did not see any mutations with recognized hyperlinks to human adaptation.

He added that the community in Texas seems to be the one one utilizing the wastewater sequencing expertise, however that H5N1 might be current in wastewater in different areas. If the virus turns into extra of an issue, Tisza mentioned wastewater sequencing could also be one of the best ways to determine new adaptive mutations. 

CDC launches ferret experiments

In a Could 10 response replace, the CDC mentioned greater than 260 folks have up to now been monitored for H5N1 signs following publicity to contaminated or probably contaminated animals. Of at the least 33 who had flulike signs, no further human instances have been reported past an preliminary case in a Texas dairy employee who had conjunctivitis.

The CDC mentioned it’s nonetheless in talks with a number of states about state-led subject epidemiologic investigations.

In the meantime, the group mentioned it’s shifting forward with scientific work to raised characterize the virus, Final week it experimentally contaminated ferrets with the virus that contaminated the Texas dairy employee to evaluate illness severity and transmission underneath totally different contact eventualities. Scientists usually use ferrets as a mannequin to evaluate flu viruses as a result of they get sick and transmit them just like folks.

Outcomes are anticipated in about 3 weeks, and the CDC mentioned experimental an infection of varied cell strains will observe.

In different developments:

The US Division of Agriculture (USDA) Animal and Plant Well being Inspection Service (APHIS) reported extra outbreaks in poultry in three states, together with two which have reported H5N1 in dairy herds. Idaho reported two extra poultry outbreaks, each in Jerome County. One occurred at a farm housing 1,000 birds and the opposite struck a yard location that has 20 birds. Michigan reported one other outbreak in Ionia County, which affected a yard flock. And California reported a detection at a live-bird market in San Francisco.An animal influenza professional group of the World Group for Animal Well being and the UN Meals and Agriculture Group, referred to as OFFLU, in the present day issued a press release on H5N1 in dairy cows, noting that the B3.13 genotype hadn’t been detected in poultry earlier than it turned up in cattle. Earlier than November 2023, it had been seen in only some wild birds and one skunk. Thus far, B3.13 hasn’t been detected exterior of the US, however the group mentioned it continues to watch the scenario.