California is currently facing a surge of deadly infectious diseases, with several public health threats spreading rapidly across the state and raising concerns for neighboring regions, especially Arizona. The most notable threats include a drug-resistant fungus, a spike in whooping cough cases, and the continued spread of H5N1 bird flu among livestock.
Drug-Resistant Fungus: Candida auris
A particularly alarming development is the spread of Candida auris, a drug-resistant fungus that has been labeled an “urgent threat” by the Centers for Disease Control and Prevention (CDC). This fungus, which can cause life-threatening infections, is spreading rapidly in hospitals and senior care facilities across California.
In 2023, California reported 1,566 infections—more than any other state. Nationwide, cases have more than doubled annually, with over 4,500 reported in 2023.
C. auris is especially dangerous because it is resistant to many antifungal medications and can spread quickly through direct contact or contaminated surfaces. The fungus is particularly deadly for the sick and elderly, with more than one in three infected patients dying from the illness. The CDC has emphasized the urgent need for improved surveillance, faster diagnostics, and strict infection control measures to contain its spread.
Whooping Cough Cases Nearly Double
California is also experiencing a significant resurgence of whooping cough (pertussis), a highly contagious respiratory disease that poses the greatest risk to infants and young children. As of late April 2025, California had reported 590 cases, contributing to a nationwide total of over 9,000 cases—nearly double the number seen during the same period last year. The West Coast, including California, Oregon, and Washington, has been particularly hard hit…