A fourth human case was reported in Colorado by US health authorities.
ADVERTISEMENTThere have now been four human cases of highly pathogenic avian influenza, known as bird flu, in the US linked to an outbreak among dairy cows.
The US Centers for Disease Control and Prevention (CDC) reported that a dairy worker in the state of Colorado tested positive for the virus.
Three other cases have been reported in the US since April, one in Texas and two in Michigan.
The person reported eye symptoms, received an antiviral treatment, and recovered from the infection.
The dairy worker was being monitored due to their proximity to bird flu-infected cattle.
The infection "does not change CDC’s current H5N1 bird flu human health risk assessment for the US general public, which the agency considers to be low," the governmental agency said.
H5N1 bird flu is currently circulating in wild birds and has caused outbreaks in US poultry and dairy cows. It has so far impacted nearly 140 dairy cow herds in 12 states, according to the CDC.
In a May report, the European Centres for Disease Prevention and Control (ECDC) assessed the risk of infection from highly pathogenic avian influenza in Europe to be "low for the general population and low-to-moderate for those with activities that expose them to infected animals or a contaminated environment".
The ECDC said that the genotype of the virus detected in humans and cows in the US has "not currently been detected in Europe".
