Highly Pathogenic Avian Influenza A(H5N1) Virus Infections in Humans

Highly pathogenic avian influenza A(H5N1) viruses have caused widespread infections in dairy cows and poultry in the United States, with sporadic human cases.
Methods: The study analyzed 46 U.S. human cases of H5N1 from March to October 2024 using standardized case-report forms and laboratory testing.
Results: Most cases were mild and involved conjunctivitis; all had exposure to infected animals. No hospitalizations or deaths occurred, and no human-to-human transmission was found. PPE use was suboptimal.
Conclusions: H5N1 infections caused mild illness in exposed adults, mostly involving the eyes. Enhanced surveillance and biosecurity are needed to reduce exposure risks.

Highly pathogenic avian influenza A(H5N1) viruses have caused widespread infections in dairy cows and poultry in the United States, with sporadic human cases.
Methods: The study analyzed 46 U.S. human cases of H5N1 from March to October 2024 using standardized case-report forms and laboratory testing.
Results: Most cases were mild and involved conjunctivitis; all had exposure to infected animals. No hospitalizations or deaths occurred, and no human-to-human transmission was found. PPE use was suboptimal.
Conclusions: H5N1 infections caused mild illness in exposed adults, mostly involving the eyes. Enhanced surveillance and biosecurity are needed to reduce exposure risks.