A second person in Missouri caught bird flu without exposure to infected animals

Blood tests have confirmed that a second individual in Missouri has contracted the H5N1 bird flu virus without any known exposure to infected animals or contaminated food. This person, who lived with the initial patient and exhibited symptoms simultaneously, tested positive for antibodies indicating a past infection. The Centers for Disease Control and Prevention (CDC) conducted these specialized tests to investigate potential human-to-human transmission, although results suggest that such transmission is not common. The initial patient is the first known case in the U.S. of H5N1 infection without apparent exposure to infected animals. While over two dozen cases of H5N1 have been reported in the U.S. this year, most involved direct contact with infected poultry or cattle. The CDC has ruled out widespread human transmission, as health-care workers who treated the patient did not test positive for the virus. However, the exact source of infection for both individuals remains unclear, and experts caution that the possibility of person-to-person transmission cannot be entirely dismissed. Symptoms in both cases were atypical for flu, primarily gastrointestinal, raising further questions about the nature of their illness. The CDC is enhancing testing capabilities and educating health-care providers on identifying potential cases of bird flu.

- A second Missouri resident has tested positive for H5N1 bird flu without known animal exposure.

- The CDC's tests indicate that human-to-human transmission is unlikely but not impossible.

- Most H5N1 cases in the U.S. this year involved direct contact with infected animals.

- Symptoms in the confirmed cases were atypical, complicating the investigation.

- The CDC is improving testing access and provider education regarding bird flu.