H5 Bird Flu California: 3rd Human Case Confirmed | CDC Update
- The Centers for Disease Control and Prevention (CDC) has announced a third confirmed case of H5 bird flu in a person in California.
- The patient experienced mild symptoms, similar to the other cases, including conjunctivitis.
- Since 2022, there have been 18 human cases of H5 bird flu reported in the U.S., with 17 of those occurring in 2024.
The CDC confirms a third human case of H5 bird flu in California, linked to exposure to infected dairy cows. This confirms a trend of animal-to-human spread among agricultural workers, but the CDC maintains that the risk to the general public remains low. All three cases presented mild symptoms, and no individuals required hospitalization. The agency is actively monitoring, conducting testing, and providing updates, as reported by News Directory 3. Since 2022, the U.S. has seen 18 H5 bird flu cases in humans. Genetic sequencing of the new california case and two others is underway to monitor for changes. Discover what’s next as the CDC tracks developments.
Third Human Case of H5 Bird Flu Confirmed in California
The Centers for Disease Control and Prevention (CDC) has announced a third confirmed case of H5 bird flu in a person in California. This case, like the previous two, involved occupational exposure to infected dairy cattle. All three individuals were dairy workers from seperate farms and had no known contact with one another, suggesting the virus spread from animals to humans.
The patient experienced mild symptoms, similar to the other cases, including conjunctivitis. None of the individuals required hospitalization. According to the CDC, the detection of H5 bird flu in people exposed to infected animals was not unexpected and does not change their assessment that the risk to the general public remains low.
Since 2022, there have been 18 human cases of H5 bird flu reported in the U.S., with 17 of those occurring in 2024. The CDC is currently awaiting confirmatory testing results for two additional presumptive positive specimens from California.
CDC Lab Update
Genetic sequencing of the frist two California cases revealed clade 2.3.4.4b A(H5N1) viruses, closely related to those found in infected dairy cattle. The complete genome sequence from one case (A/California/135/2024) confirmed it as a B3.13 genotype virus. No genetic changes were observed that would suggest an increased ability to infect or spread among people, nor any reduction in susceptibility to antiviral medications. These sequences are publicly available on Gisaid and have been submitted to GenBank. Sequencing of the third confirmed case is in progress.
The CDC emphasizes the importance of following recommended precautions for individuals exposed to infected or perhaps infected animals. Those with close or prolonged, unprotected contact with infected birds, livestock, or contaminated environments face a higher risk of infection.
what’s next
The CDC will continue monitoring the situation closely, conducting further testing, and providing updates as more data becomes available regarding the spread of H5 bird flu and its potential impact on public health.