NBC News
A fourth person tested positive for bird flu in the outbreak linked to dairy cows. The diagnosis was made this time in Colorado.
The Centers for Disease Control and Prevention (CDC) reported Wednesday that the patient, a worker at a dairy farm where cows had also tested positive for the virus, developed eye symptoms and recovered after receiving the antiviral drug Tamiflu.
The case reflects the evolution of the disease seen in two previous cases in this outbreak, in dairy workers in Texas and Michigan. The only symptoms presented by both were conjunctivitis. A third patient, also from Michigan, presented upper respiratory symptoms, such as sore throat, cough and nasal congestion.
All patients have recovered, and none were related to each other.
“Based on the information available at this time, this infection does not change CDC’s current assessment of the risk from H5N1 avian influenza to the general public in the United States, which the agency considers to be low,” the CDC said in a news release Wednesday.
According to the CDC, there is no evidence of an increase in flu-like illnesses that suggests the virus – a strain called H5N1 – is spreading widely among people.
Since the outbreak was first detected in March, more than 780 people exposed to sick cows have been followed and 53 have been tested for the virus, the CDC said in a briefing with reporters Tuesday.
Federal health authorities said they could be in the coming weeks 4.8 million doses of a vaccine available against this particular strain of flu. Drugmaker Moderna is also in the early stages of developing an mRNA vaccine against bird flu.
As of Wednesday, 139 herds in 12 states had been affected, the Department of Agriculture reported.
The CDC recommended that anyone who comes into contact with dairy cattle wear protective gear, including safety glasses, waterproof aprons and boots that can be disinfected. Health officials also warned against consumption of raw, unpasteurized milkIt has been shown with milk samples that pasteurization neutralizes the virus.