The number of measles cases nationwide has risen by 42 the in past week, the Centers for Disease Control and Prevention (CDC) reported today in its latest update. There are now 1,723 confirmed measles cases this year, reported by 43 jurisdictions.

Eighty-seven percent of measles cases are outbreak-associated, and there have been 45 US outbreaks in 2025. Among measles patients, 92% have been unvaccinated or had an unknown vaccine status. Only 4% have received both doses of measles-containing vaccine.

Last year the United States had 285 measles cases. US measles activity is the highest it has been since measles was declared eliminated in the country in 2000. 

Lost elimination status for Americas

Earlier this week, Canada lost its elimination status after it failed to contain a nationwide outbreak for 12 months that has topped 5,000 infections. This dubious milestone also meant a loss of elimination status for the entire Americas region. 

The United States will be on track to follow Canada in January 2026, which will mark 12 months since a large West Texas measles outbreak began. 

Current hot spots include the Utah-Arizona border and Upstate South Carolina. 

A new study of children with ear infections suggests that wider uptake of "watchful waiting" could help reduce unnecessary antibiotic use, US researchers reported yesterday in the Journal of the Pediatric Infectious Diseases Society.

Led by researchers with the University of Utah and Intermountain Health, the multicenter, retrospective observational study analyzed data on children ages six months to 17 years who received a diagnosis of acute otitis media (AOM) in ambulatory practice settings at health systems in Illinois, Colorado, and Utah from July 2018 through December 2023. 

The aim was to determine visits in which children received an immediate antibiotic prescription (within 2 days of the index visit) and those that used watchful waiting, a strategy that can involve monitoring symptoms and prescribing an antibiotic only if it's needed, or a delayed antibiotic prescription. The researchers also evaluated the outcomes associated with the two approaches.

The study authors note that roughly 100 million antibiotic courses are prescribed for children with AOM annually, though over 80% of cases resolve on their own.

"Randomized clinical trials have shown that watchful waiting can reduce antibiotic use for AOM by approximately 60% with similar patient outcomes and parent satisfaction to immediate antibiotic use," the authors wrote. "Despite these favorable data, evidence suggests watchful waiting is utilized in only 5-20% of cases."

Favorable clinical outcomes 

Of the 140,579 visits for AOM, an immediate antibiotic was prescribed in 84.4%, and watchful waiting was used in 15.6%. Of the watchful-waiting patients, 56% were not prescribed an antibiotic, and 44% received a delayed prescription. Rates of treatment failure and recurrence were low in both groups, with only 6% of the watchful-waiting group and 7% of the immediate antibiotic group receiving any antibiotic 3 to 30 days after the index visit.

"When watchful waiting was utilized, clinical outcomes were favorable as evidenced by the infrequent need for a new antibiotic prescription in the 30 days after the index visit," the authors wrote. "Interventions to scale up use of watchful waiting for AOM may therefore be a high-yield approach to reduce unnecessary antibiotic exposure for children with AOM."

A study of raw cow and sheep milk in Pakistan found high levels of antibiotic-resistant bacteria, researchers reported yesterday in PLOS One.

In the study, researchers from Abdul Wali Khan University Mardan assessed raw milk samples from dairy cattle and ewes for the prevalence of Staphylococcus epidermidis, a gram-positive bacterium that's a common cause of subclinical mastitis, which can reduce milk quality and yield. 

They also evaluated antibiotic susceptibility and resistance gene carriage in samples that were positive for S epidermidis, which is known for extensive antimicrobial resistance and its ability to share resistance genes with other staphylococcal species. 

The study authors note that over 95% of milk in Pakistan is consumed in its raw form. And although S epidermidis is commonly found on human skin and is generally harmless, there is concern that drug-resistant strains in milk could spread resistance genes to more harmful bacteria like methicillin-resistant Staphylococcus aureus.

"Given the public health implications of antibiotic-resistant S. epidermidis in dairy production, it is essential to monitor the prevalence and resistance profiles of this pathogen in milk," the study authors wrote.

Half of S epidermidis isolates are multidrug-resistant

The overall prevalence of subclinical mastitis was 26%, and 40 (12.9%) of the 310 milk samples collected tested positive for S epidermidis. 

Antibiotic susceptibility tests showed high resistance rates (95%) to penicillin and erythromycin; moderate rates of resistance to cotrimoxazole, doxycycline, clindamycin, and chloramphenicol; and low rates of resistance to levofloxacin and ciprofloxacin. Half of the S epidermidis isolates were classified as multidrug-resistant. 

Among the resistance genes identified, ermC was most prevalent (87.5%), followed by tetK (80%) and mecA (45%).

The authors say widespread use of antibiotics to treat mastitis and other diseases of dairy cattle and sheep likely explains the high levels of resistance.

"The presence of multidrug-resistant Staphylococcus epidermidis in raw milk highlights how on-farm antibiotic use directly shapes public health risks," they said in a journal press release. "These findings emphasize the urgent need for responsible antibiotic use and improved hygiene practices in the dairy sector to reduce the risk of antimicrobial resistance transmission through the food chain."