MRSA occurs more in summer, fall

PROVIDENCE, R.I., March 25 (UPI) -- Methicillin-resistant Staphylococcus aureus infections increase during the summer and fall and the increase is mostly among children, U.S. researchers found.

Lead author Dr. Leonard Mermel, medical director of the department of epidemiology and infection control at Rhode Island Hospital in Providence, and colleagues examined MRSA samples submitted to the hospital's microbiology laboratory over a 10-year period.

The findings, published in the journal PloS ONE, indicate there were approximately 1.85 times as many community-associated MRSA infections -- acquired by people who have not been hospitalized or had a medical procedure -- among pediatric patients. Among the same group, there were 2.94 times as many hospital-associated-MRSA infections -- acquired in a hospital of medical facility -- in the third and fourth quarters of the year than in the first two quarters.

In adults, there were 1.14 times as many community-associated-MRSA infections in the second two quarters as in the first two quarters, but no seasonal variation was observed in adult hospital-associated-MRSA infections.

"The presence of both factors, heat and humidity, may be critically important in providing the environmental conditions that facilitate heavy grown of S. aureus on the skin," Mermel says in a statement.