By Julie Steenhuysen
(Reuters) -A second Missouri healthcare worker who had contact with a hospitalized patient infected with bird flu developed mild respiratory symptoms but was not tested for the virus, U.S. officials said on Friday.
The number of people who were in contact with the hospitalized bird flu patient in Missouri and developed symptoms is now up to three, officials said. All three have recovered.
The other two symptomatic cases included a healthcare worker who tested negative for influenza and a household contact of the patient who developed symptoms at the same time as the hospitalized patient, but was never tested.
The U.S. Centers for Disease Control and Prevention said serologic testing will be offered to the second healthcare worker.
Unlike prior U.S. bird flu cases this year, the Missouri patient had no known contact with infected animals, raising concerns the virus currently circulating in dairy cattle may have mutated in a way that makes it spread more easily in people.
CDC officials said in a Sept. 12 briefing the agency has been unable to determine if the Missouri case was related to the virus infecting U.S. dairy cattle.
Missouri is leading the state’s bird flu investigation with remote assistance from the CDC.
The state’s health officials said in an email last week Missouri is considering taking blood samples to look for antibodies that would indicate prior exposure to bird flu.
The confirmed Missouri case occurred in a patient who was admitted to the hospital with underlying health conditions and was tested for influenza as a part of his workup. It was unclear whether the patient’s underlying conditions caused the symptoms or the flu.
The Missouri case was the 14th person in the United States to be diagnosed with bird flu this year. The other 13 cases were among farm workers and linked to bird flu outbreaks on poultry or dairy farms.
Bird flu has infected more than 200 dairy herds in 14 states since March, according to US Department of Agriculture data.
