Welcome to the thirty-seventh edition of FOI Clinical. Each week, we'll send you a briefing on outbreak news. When something urgent breaks, you'll get an alert the same day.
In this edition
H5N1: dairy cattle and a human case in Washington – Measles: 4,410 cases and six deaths YTD – Seasonal respiratory virus activity – Salmonella: raw oysters from Virginia – National surveillance, week 40 – Dengue: Florida reports 368 cases – Vibrio vulnificus: seven deaths in Louisiana – Ebola: nine cases in Kenya, one in Nigeria, an eighth province in Congo
National interest
H5N1 — dairy cattle in Washington, and a human case
On October 8, the Washington State Department of Agriculture announced the state's first detection of highly pathogenic avian influenza A(H5N1) in dairy cattle. Two farms in Yakima County were initially affected; both are under quarantine. BEACON has since reported that a third herd and then five more, bringing the state to eight, all in Yakima County
One human case has been reported in connection with the clusters. The Yakima Health District reported on October 15 a confirmed case in a county resident exposed to infected cattle at a local dairy. The patient has not had severe illness, has not been hospitalized and is isolating at home. Close contacts are being monitored for symptoms. The state health department's case table lists it as Washington's first human case linked to dairy cattle; its 15 earlier cases followed exposure to poultry or a backyard flock. CDC's national count, updated October 15, reports 72 human cases since 2024, 42 of them linked to dairy herds. CDC still rates the public health risk as low and reports no person-to-person spread.
The agriculture department said it had run more than 7,000 surveillance tests over the previous two years, all negative, making it less likely that spread has been ongoing undetected. Nationally, dairy cattle in 19 states have been infected since the outbreak began in March 2024.
Clinical note: the district's health advisory to providers asks clinicians to take an exposure history from every patient with suspected or confirmed influenza: sick or dead animals including livestock, raw milk or raw pet food, or contact with a suspected case. This is especially important now that seasonal H1N1 is rising at the same time. Positive influenza A specimens should be subtyped, and an influenza A result that cannot be subtyped must be reported to public health authorities immediately. Add a conjunctival swab if the patient has conjunctivitis.
Measles — 4,410 cases, six deaths YTD
CDC's measles page, updated October 16, reports 4,410 confirmed cases, up from 4,080 a week earlier. CDC's national death count has risen from two to three, a figure it says is subject to change while reviews are completed. A representative from the Department of Health and Human Services told Reuters that the National Center for Health Statistics had received a report of the third death and verified measles as the underlying cause. Pennsylvania state has reported six measles-associated deaths to date. Last week, CDC agreed to send Pennsylvania additional support for the outbreak investigation.