Building the Future of Biodefense

Recommendation: The primary impact of highly pathogenic avian influenza (HPAI) outbreaks in commercial flocks is the increased cost of eggs or poultry products when outbreaks become more widespread. Organizations sensitive to egg and poultry prices should have a contingency plan for price volatility. PHC recommends that continuity plans be reviewed and updated in preparation for high-consequence infectious disease threats.

Situation: Japan reported a suspected case of HPAI on a quail farm in Asahi City, Chiba Prefecture, affecting around 108,000 birds. Elsewhere, in Taiwan, officials reported 2 instances of improper procedures related to avian influenza detections in birds. In Taichung City, reports of a large number of dead chickens due to avian influenza at a farm led to an investigation, which found that the business owner failed to report the incident proactively. In Miaoli County, 235 H5N1-infected chicken carcasses were abandoned at a drainage ditch in Houlong Township. The illegal disposal is suspected of violating the Animal Infectious Disease Prevention and Control Act, prompting an investigation. Improper disposal of avian influenza-infected carcasses poses environmental and health risks, including increased human exposure to H5N1. [Confidence: Very High]

Recommendation: Heat is the top killer among extreme weather events, and the heat wave in Victoria, Australia, is a reminder to review plans for such events. Organizations should provide adequate cool water, frequent rest breaks, and shade or a cool rest area for employees working outside. Organizations should consider providing flexible scheduling options, especially for outdoor workers or workers commuting by transit modalities that lack air conditioning. Organizations may wish to include cooling tips in their wellness communications.

Situation: Victoria health officials issued a health advisory due to a rare heatwave event. Officials stated that heat-related illness kills more Australians than any other natural disaster and can affect anyone, especially older adults, young children, pregnant women, people with health conditions, and those who are socially isolated. Extreme heat can cause serious or fatal conditions like heat exhaustion, heatstroke, heart attack, or stroke, and worsen existing illnesses. Officials urged the public to stay cool and hydrated, plan to avoid extreme heat, and recognize early warning signs. The source link provides guidance on how to prepare and stay healthy. [Confidence: Very High]

Recommendation: No locally acquired human West Nile virus (WNV) cases have ever been detected in Denmark, but competent mosquito vectors, primarily from the Culex genus, are present in the country. Peak mosquito season (May to September) has ended, but organizations in Denmark should be prepared to reduce mosquito habitats by eliminating sources of standing water and applying insecticides to outdoor water storage containers when warmer weather returns.

Situation: Denmark reported that WNV antibodies were detected in 4 horses, indicating a previous infection. These detections were the first indication of WNV circulation in the country. The samples were collected in the fall of 2025 from asymptomatic horses. Health officials stated that the risk of WNV in Denmark is still very small, but climate change can make northern areas more conducive to mosquito activity, increasing the risk of mosquito-borne diseases, like WNV, across Europe. WNV was previously detected in horses and people in 2024 in northern Germany, near the Danish-German border. [Confidence: Very High]

Recommendation: Organizations in Santa Clara County and San Mateo County, California, should provide flexible work schedules to support employees making vaccine appointments for themselves or family members. Measles is highly contagious and can quickly spread among unvaccinated individuals in a work environment.

Situation: California health officials reported a measles virus detection in wastewater in Santa Clara County that was collected on 1/10 from the Palo Alto sewershed. Wastewater testing of samples each day from 1/11-15 did not detect measles. The Palo Alto sewershed includes waste from communities in northern Santa Clara County and a small portion of San Mateo County. The detection suggests that at least 1 individual in the community or traveling through the community around that time was infectious with measles. No measles cases have been confirmed within the county at this time, but a measles case was previously reported in San Mateo County (see PHC alert 1/9). [Confidence: Very High]