MRSA Infections May Vary by Season

TUESDAY, March 29 (HealthDay News) — Dangerous methicillin-resistant staphylococcus aureus, or MRSA, infections occur more often in the summer and fall, and this seasonal increase is more common in children than adults, a new study reports.

The findings came from an analysis of MRSA cases that occurred at Rhode Island Hospital, in Providence, over 10 years.

The researchers found that children’s infections were higher in the third and fourth quarters of the year than in the first two quarters. In the later months, children had 1.85 times more MRSA infections that had been contracted outside of a health-care setting, called community-associated MRSA infections, and 2.94 times more hospital-associated infections.

By contrast, adults had 1.14 times more community-associated MRSA infections in the last two quarters of the year than in the first two quarters, and there was no seasonal variation in hospital-associated infections, according to the study, published online March 23 in PLoS One.

The researchers also reviewed published articles from the past 70 years, finding an increase in MRSA infections during summer and autumn in many temperate regions of the world and during the warmest months of the year in tropical regions.

Skin moisture plays an important role in the growth of microbes, and the presence of both heat and humidity may offer ideal conditions for the proliferation of S. aureus, the researchers said.

“It is hoped that this study will promote further investigation into the seasonality of S. aureus infections to better understand the biologic basis for this observation,” lead author Leonard Mermel, medical director of the department of epidemiology and infection control at Rhode Island Hospital, said in a hospital news release.

More information

The U.S. Centers for Disease Control and Prevention has more about MRSA infections.