Building the Future of Biodefense

Recommendation: The polio vaccine is more than 99% effective in preventing poliovirus infection. Travelers to Zambia should verify their polio vaccination status before travel.

Situation: Zambia detected vaccine-derived poliovirus type 2 in an environmental sample from Lusaka. No paralysis cases have been recorded. The detected virus is genetically similar to detections in Namibia and Angola, as well as neighboring Zimbabwe and Malawi (see PHC alert on 2/2). [Confidence: Very High]

Recommendation: Employers can support employees in obtaining mpox vaccinations by providing flexible work schedules. Information on the availability of mpox vaccines and treatment can also be included in employee wellness communication.

Situation: Austria reported 2 mpox clade 1b cases this month. Before these recent detections, only mpox clade 2 cases had been detected in the country. Across the European Union, 80 other mpox clade 1 cases were reported from 1/1 to 2/18 in Spain (36), Italy (19), Germany (10), France (8), the Netherlands (5), Czechia (1), and Ireland (1). Incidence of clade 1 has steadily increased over recent months in the European Union countries, rising from 8 cases reported in September 2025 to 73 cases reported in January 2026. See PHC alerts on 1/20 and 10/24 for earlier info. [Confidence: Very High]

Recommendation: Organizations and employees should avoid all contact with the Potomac River and surrounding soil, including swimming, boating, wading, or fishing, while the sewage spill and repairs continue to reduce the risk of infection. Employees should practice good hand hygiene after potential exposure, prevent pets from drinking from the river, rely on safe drinking water, follow guidance from local authorities, and seek medical attention if gastrointestinal symptoms develop after possible contact.

Situation: The District of Columbia declared a local emergency and requested federal support after the Potomac Interceptor sewage break. The request seeks cost reimbursement, immediate federal aid for water monitoring and engineering, and long-term infrastructure improvements. According to media sources, the rupture of the 60-year-old Potomac Interceptor on 1/19 caused one of the largest sewage spills in US history, releasing millions of gallons of waste into the Potomac River. Repairs are expected to take months, with full replacement potentially taking up to 10 months. E. coli, Staphylococcus aureus, and antibiotic-resistant MRSA have been detected in the river, and officials advise residents to avoid contact with the water. DC Water built a bypass, but sporadic overflows continue. [Confidence: Very High]