CDC Links California Child’s Bird Flu Case to Livestock Outbreaks
Source: DairyNews.today
Federal health officials have confirmed that a strain of avian influenza detected in a California child is genetically linked to recent outbreaks in U.S. dairy cattle and poultry.
The Centers for Disease Control and Prevention (CDC) detailed the findings in a Dec. 10 technical update, following the initial Nov. 22 report of the case involving a child from the San Francisco Bay Area. Genetic analysis of the virus revealed similarities to strains found in livestock, particularly those tied to B3.13 viruses detected in humans, cattle, and poultry in California.
Key Findings
The CDC emphasized that the genetic data, though incomplete, establish a strong connection between the child’s infection and ongoing avian influenza outbreaks in livestock. However, they underscored that the virus did not exhibit mutations associated with higher transmissibility among humans.
“This strain remains similar to those circulating in livestock and does not show adaptations that increase the likelihood of human-to-human spread,” the CDC stated.
Health officials also noted that the virus in this case is distinct from the strain linked to a severe infection in British Columbia, Canada.
Challenges in Investigation
The CDC encountered technical challenges in analyzing the child’s case due to the low levels of viral RNA present in saliva samples. Advanced sequencing methods were used to generate partial genetic data, enabling the linkage to livestock outbreaks.
The child’s specific exposure source remains unidentified, though the CDC highlighted the importance of ongoing surveillance to improve understanding of transmission pathways.
Human Impact of Bird Flu in 2024
The case brings the total number of U.S. bird flu infections in humans to 58 this year, with 32 reported in California. Most infections have been associated with exposure to infected dairy cattle and have resulted in mild symptoms.
The current bird flu outbreak, which began in 2022, has significantly impacted wildlife and livestock. More than 108 million birds have been affected across the U.S., and the virus has been detected in dairy cattle in 15 states. Last month, the first avian influenza case in a pig was also reported.
Low Risk to Public
Despite the outbreak’s scope, the CDC reiterated that the risk of bird flu to the general public remains low. Human infections in the U.S. have not resulted in sustained transmission, and person-to-person spread has only occurred in limited cases overseas, primarily among close contacts of infected individuals.
The California Department of Public Health affirmed that bird flu has never spread between people in the U.S., adding that public health surveillance would continue to monitor any changes in the virus or its behavior.
“Robust monitoring at local, state, and federal levels remains critical to identify and respond to potential risks,” the CDC stated.
Looking Ahead
Health officials continue to stress the importance of precautionary measures for those in direct contact with livestock, emphasizing proper biosecurity protocols. Surveillance efforts will remain focused on both human cases and potential mutations in the virus as the outbreak persists.
Key Findings
The CDC emphasized that the genetic data, though incomplete, establish a strong connection between the child’s infection and ongoing avian influenza outbreaks in livestock. However, they underscored that the virus did not exhibit mutations associated with higher transmissibility among humans.
“This strain remains similar to those circulating in livestock and does not show adaptations that increase the likelihood of human-to-human spread,” the CDC stated.
Health officials also noted that the virus in this case is distinct from the strain linked to a severe infection in British Columbia, Canada.
Challenges in Investigation
The CDC encountered technical challenges in analyzing the child’s case due to the low levels of viral RNA present in saliva samples. Advanced sequencing methods were used to generate partial genetic data, enabling the linkage to livestock outbreaks.
The child’s specific exposure source remains unidentified, though the CDC highlighted the importance of ongoing surveillance to improve understanding of transmission pathways.
Human Impact of Bird Flu in 2024
The case brings the total number of U.S. bird flu infections in humans to 58 this year, with 32 reported in California. Most infections have been associated with exposure to infected dairy cattle and have resulted in mild symptoms.
The current bird flu outbreak, which began in 2022, has significantly impacted wildlife and livestock. More than 108 million birds have been affected across the U.S., and the virus has been detected in dairy cattle in 15 states. Last month, the first avian influenza case in a pig was also reported.
Low Risk to Public
Despite the outbreak’s scope, the CDC reiterated that the risk of bird flu to the general public remains low. Human infections in the U.S. have not resulted in sustained transmission, and person-to-person spread has only occurred in limited cases overseas, primarily among close contacts of infected individuals.
The California Department of Public Health affirmed that bird flu has never spread between people in the U.S., adding that public health surveillance would continue to monitor any changes in the virus or its behavior.
“Robust monitoring at local, state, and federal levels remains critical to identify and respond to potential risks,” the CDC stated.
Looking Ahead
Health officials continue to stress the importance of precautionary measures for those in direct contact with livestock, emphasizing proper biosecurity protocols. Surveillance efforts will remain focused on both human cases and potential mutations in the virus as the outbreak persists.
