Global deaths from Staphylococcus aureus–associated lower respiratory tract infections (LRTIs) in older adults nearly tripled from 1990 to 2021, according to a study published yesterday in BMC Infectious Diseases.

Using data from the MICROBE (Multidisciplinary Investigation of Clinical Research Outcomes and Burden Estimates) database, Chinese researchers analyzed estimates on deaths and disability-adjusted life years (DALYs) associated with 22 pathogens and 84 drug-pathogen combinations across 204 countries. They focused specifically on S aureus, including deaths and DALYs attributable to methicillin-resistant S aureus (MRSA). 

S aureus colonizes skin and mucosal surfaces, and the researchers note that older adults are particularly vulnerable to S aureus LRTIs because of the deterioration of the immune system that accompanies aging, the prevalence of comorbidities, and frequent contact with healthcare facilities. MRSA compounds the problem by limiting treatment options.

“The global spread of antimicrobial resistance (AMR) in S. aureus, especially methicillin resistance (MRSA), represents a critical public health issue,” they wrote.

MRSA contributes significantly to mortality

S aureus–associated LRTI deaths in older adults (age 70 and older) rose from 83,363 in 1990 to 250,347 in 2021, and the mortality rate increased from 41.3 per 100,000 to 50.6. DALYs rose from 1.15 million to 3.29 million. MRSA contributed significantly to mortality. Deaths from MRSA LRTIs in older adults rose from 22,481 in 1990 to 75,038 in 2021, and death rates from 11.1 per 100,000 to 15.2 per 100,000. 

In 2021, MRSA mortality among older adults was 6.7 times higher than in adults aged 50 to 69, 9.5-fold higher than in children under 5 years, and more than 70-fold higher than in those aged 5 to 49. DALYs mirrored these trends. The highest mortality burden in 2021 was seen in high-income countries, a finding the study authors attribute in part to rapid demographic aging, while countries in sub-Saharan Africa recorded the highest DALY rate.

“This analysis demonstrates increasing S. aureus LRTIs burden in older adults globally,” the authors concluded. “Our findings underscore the urgent need to prioritize targeted interventions and antimicrobial stewardship to prevent the growing burden of resistant pathogens.”

• Today, the World Health Organization (WHO) announced that the Netherlands has reported one more case of hantavirus in a crew member who left the MV Hondius cruise ship in Tenerife, Canary Islands, and has been isolating in the Netherlands since then, for a total of 12 cases and three deaths tied to the outbreak. There have been no deaths in 20 days. “The situation is stabilizing,” WHO Director-General Tedros Adhanom Ghebreyesus, PhD, said on X. “WHO is actively monitoring all quarantined passengers and crew alongside national governments. Surveillance will continue until the incubation period ends for everyone who was on board.”
• This week, the Global Polio Eradication Initiative reported one circulating vaccine-derived poliovirus type 2 (cVDPV2) case each in Nigeria and Yemen and one circulating vaccine-derived poliovirus type 1 (cVDPV1) case in South Sudan. The Nigerian cVDPV2 patient, from Kebbi state, had a paralysis onset of March 17. The country has documented 24 cases so far this year. In Yemen, the cVDPV2 patient, from Abyan governorate, became paralyzed on December 6, 2025. The 2025 total in that country is now 31. The cVDPV1 patient in South Sudan, from Upper Nile state, became paralyzed on March 27, the third such case this year.
• Jeffery Taubenberger, MD, PhD, acting director of the National Institute for Allergy and Infectious Diseases (NIAID), stepped down from his post two weeks ago, senators revealed yesterday during a Senate Appropriations Committee meeting, leaving another National Institutes of Health (NIH) agency with no leader. A virologist, Taubenberger was appointed acting director in April 2025 after the Trump administration ousted Jeanne Marrazzo, MD, MPH. In the meeting, NIH Director Jay Bhattacharya, MD, PhD, said NIAID needed new leadership because it is shifting away from its focus on civilian biodefense. In a statement today, the Infectious Diseases Society of America and other professional organizations said that such federal leadership departures endanger everyone.