Hot Topics for March 20, 2025: Outbreak Updates and Global Health Disruptions

Saskia v. Popescu, PhD, MPH, MA, CIC, FAPIC, presents Infection Control Today’s Hot Topics in Infection Prevention

Outbreak Updates

Here are some quick updates on what we’re facing currently:

Measles: The last CDC update from March 14, 2025, notes 301 confirmed cases and 2 deaths (1 confirmed and 1 under investigation), with 17% of cases hospitalized. For reference, in all of 2024, there were 285 total cases. Of the 301 cases in 2025, the majority (42%) have been in those 5-19 years of age, 34% under the age of 5, and 21% in those 20+. Ninety-five percent of cases occurred in unvaccinated individuals or those with unknown vaccination status, while 3% were seen in individuals who received one dose of the MMR vaccine.

Per the CDC, “There have been 3 outbreaks (defined as 3 or more related cases) reported in 2025, and 93% of cases (280 of 301) are outbreak-associated. For comparison, 16 outbreaks were reported during 2024, and 69% of cases (198 of 285) were outbreak-associated.” Here’s a good article discussing how we can respond and how much worse this outbreak could potentially get.

H5N1: The USDA just shared a new biosecurity assessment and audit resource to help poultry farms ramp up prevention and response to the ongoing outbreak. As of March 18, 2025, there have been 70 human cases (including 1 death) within the US, of which the majority of exposures (40) came from dairy herds, followed by poultry farm and culling operations. Targeted surveillance has detected the virus in 12,581 wild birds across 51 jurisdictions and 989 dairy herds in 17 states.

Another strain of highly pathogenic avian influenza (HPAI), H7N9, has been identified on a poultry farm in Mississippi, which is particularly worrisome given the higher mortality rate for human cases.

Global Health Disruptions

As time progresses since the US withdrew from the World Health Organization (WHO) and froze the US Agency for International Development (USAID), we’re seeing the impact—from HIV/AIDS treatments and deaths to disruptions in malaria diagnostics and TB prevention. WHO Director-General Tedros Ghebreyesus, PhD, recently spoke at a briefing, in which he shared positive news—no new cases of Ebola have been identified in Uganda, and Burundi is now the 18^th country to roll out malaria vaccines through a childhood immunization program.

Such good news, though, was marked with sadness over the already significant impact of the cuts to direct US funding of global health through USAID, WHO, and CDC efforts. He noted—asking the US to reconsider, that “the impact of these cuts will be even greater—and we are already seeing them.” Due to stockouts, delayed deliveries, or insufficient funding, there are significant disruptions in the supply of malaria diagnostics, medications, and insecticide-treated bed nets.

“Over the last 2 decades, the US has been the largest bilateral donor to the fight against malaria, helping to prevent an estimated 2.2 billion cases and 12.7 million deaths,” Ghebreyesus continued. “If disruptions continue, we could see an additional 15 million cases of malaria and 107,000 deaths this year alone, reversing 15 years of progress.”

As Ghebreyesus explained, “The suspension of most funding to PEPFAR—the President’s Emergency Plan for AIDS Relief—caused an immediate stop to services for HIV treatment, testing, and prevention in more than 50 countries. Eight countries now have substantial disruptions to antiretroviral therapy, and some will run out of medicines in the coming months. Disruptions to HIV programs could undo 20 years of progress, leading to more than 10 million additional cases of HIV and 3 million HIV-related deaths—more than triple the number of deaths last year.”

These impacts will also be seen in surveillance and outbreak reporting, as considerable resources have gone to ensure we have early pathogen warning systems worldwide. These systems give us a heads-up when cases of emerging infectious diseases are detected to ensure rapid response and containment.