None of the health care workers or other contact have tested positive for avian flu antibodies so far — but could their illness signal human-to-human transmission?

A cluster of healthcare workers has been tested for H5N1 bird flu in what could be the first cases of human-to-human spread of the virus.

In what could be the first cases of bird flu spreading between humans in the United States, a group of potential H5N1 ...

Seven people fell ill with flu-like symptoms after contact with someone infected with H5N1, raising fears that the virus has ...

Four additional healthcare workers who cared for the Missouri patient confirmed to have H5N1 bird flu developed mild ...

Testing is ongoing among five health care workers and a household member exposed to the infected person who all came down ...

At least one household member and six healthcare workers who encountered the index case-patient are being investigated after ...

Four more health-care workers who tended to a person hospitalized with H5N1 bird flu have revealed that they had respiratory ...

The CDC said an investigation into a human H5N1 bird flu infection in Missouri has found four additional health care workers ...

Seven people in contact with a patient hospitalized with bird flu also developed symptoms, the C.D.C. reported. Some are ...

More than a month after a person in Missouri mysteriously fell ill with H5-type bird flu, investigators in the state are ...

A second health worker who cared for a person hospitalized in Missouri with H5N1 bird flu developed mild respiratory symptoms ...