US: Multiple Health Threats - Measles, HMPV, Rat Lungworm, Mercury Rule Rollback, Nanoplastics/Parkinson's Link

The United States is currently grappling with a complex array of public health challenges. Measles cases are spiking, with 2026 on track to surpass last year's high, while a highly contagious respiratory virus, Human metapneumovirus (HMPV), is spreading rapidly, particularly on the West Coast. Simultaneously, environmental concerns are mounting as mercury pollution regulations are being rolled back, and emerging research links nanoplastics to an increased risk of Parkinson's disease. Adding to the complexity, the rat lungworm parasite has now been found in Southern California, posing a risk of meningitis. These issues highlight vulnerabilities in public health infrastructure, environmental regulations, and the potential impact of emerging contaminants. The convergence of these threats underscores the need for proactive measures to protect public health and mitigate potential long-term consequences. ## Latest Update The rat lungworm parasite has been found in wild rats across three counties in Southern California (Los Angeles, Riverside, and San Diego), indicating that the risk of transmission to humans and pets is now a permanent fixture of the region's public health landscape. A highly contagious respiratory virus, Human metapneumovirus (HMPV), is spreading rapidly on the West Coast and beyond, with no specific treatment available. ## Timeline * **2026-02-07:** Measles cases are surging in the US, with 588 confirmed in January alone. An outbreak is centered in upstate South Carolina, and the Pan American Health Organization (PAHO) is considering revoking the United States' measles "eliminated" status. * **2026-02-23:** The EPA moved to repeal a Biden-era rule that limits the amount of toxic air pollution produced by coal-burning power plants, potentially increasing mercury exposure. * **2026-02-28:** Scientists warn that nanoplastics may increase the risk of Parkinson's disease by binding to alpha-synuclein in the brain. * **2026-03-06:** The rat lungworm is now endemic in Southern California, posing a risk of eosinophilic meningitis in humans. * **2026-03-06:** A highly contagious respiratory virus, Human metapneumovirus (HMPV), is spreading rapidly through the West Coast and beyond. ## What to Watch * **Measles Spread:** Monitor measles case counts and vaccination rates, particularly in areas with low coverage. Pay attention to PAHO's decision regarding the US's measles "eliminated" status. * **HMPV Impact:** Track the spread of HMPV and its impact on vulnerable populations, especially infants and the elderly. Be aware of local health advisories and recommendations for prevention. * **Environmental Health:** Follow developments related to the EPA's mercury rule rollback and potential health consequences in communities near coal-fired power plants. Stay informed about research on the long-term effects of nanoplastics exposure.