Dr. Amy Sisson, Yolo County’s public health officer, told the Board of Supervisors that COVID‑19 continues to circulate but at low levels locally while influenza A, respiratory syncytial virus (RSV) and norovirus are currently widespread. She also briefed supervisors on the state’s avian influenza (H5N1) situation and recommended precautions for people working with poultry, dairy cattle or wild birds.

Sisson said wastewater levels of SARS‑CoV‑2 in Yolo County have been “unseasonably low” since last summer. She urged residents to get the updated 2024‑25 COVID vaccine, which she said reduces emergency‑department and hospitalization risk and can be co‑administered with seasonal influenza vaccine.

On other respiratory pathogens, Sisson said influenza A and RSV are at high levels in local wastewater and that norovirus has caused school outbreaks; norovirus is not killed by hand sanitizer, she noted, so handwashing is critical for that pathogen.

On avian influenza, Sisson summarized state data: H5N1 has been detected in wild birds and, since 2024, in commercial poultry and dairy cows in California. She said more than 700 dairies in the state reported infections in cattle and that nearly 23 million birds in commercial flocks have been affected in the national outbreak. California has reported 37 human H5N1 infections, most among dairy workers; Sisson said none of those California cases had required hospitalization and there is no evidence of sustained human‑to‑human transmission.

Sisson described the public health concern: influenza viruses can reassort when a host is co‑infected by seasonal influenza and an avian strain, potentially creating a novel virus with human‑to‑human transmissibility. To reduce that possibility she recommended seasonal influenza vaccination to lower the chance of co‑infection, avoiding raw milk and raw dairy products (pasteurization kills the virus), and using personal protective equipment — including eye protection and N95 respirators — when handling poultry, dairy cows or wild birds.

Sisson said local public health is monitoring wastewater for H5 signals, that hospitals are sending flu specimens for subtyping, and that the department can provide antivirals and PPE to operators on request. She also noted the federal and state availability of free COVID tests and described county vending machines that distribute free tests and other health supplies.

During board Q&A, supervisors asked about raw milk risks and consumer warnings, whether cooked meat poses a risk (Sisson: properly cooked meat and pasteurized dairy products are not sources of infection), and testing and treatment pathways for suspected avian influenza cases. Sisson said providers should consider bird‑flu testing for patients with compatible symptoms and animal exposure and that public health can help arrange testing and antivirals when clinically indicated.

Ending: Sisson urged residents to get seasonal flu and COVID vaccines, avoid raw dairy, use handwashing to prevent norovirus and follow workplace masking guidance after COVID infection when returning to work.