Early infectious factors were not associated with multiple sclerosis (MS) risk, a recent study found. Researchers conducted a case-control study of children with MS or clinically isolated syndrome (CIS) and healthy controls enrolled at 16 clinics participating in the US Network of Pediatric MS Centers. Parents completed a comprehensive environmental questionnaire that captured early infectious exposures, habits, and illnesses in the first 5 years of life. They found:

• Questionnaire responses for 326 eligible cases (mean age 14.9, 63.5% girls) and 506 healthy pediatric subjects (mean age 14.4, 56.9% girls) were included in analyses.
• History of flu with high fever before age 5, playing outside in grass, and use of special products to treat head lice or scabies were associated with increased risk of MS in unadjusted analyses.
• In the multivariable model adjusted for age, sex, race, ethnicity, and mother's highest educational attainment, these results were not statistically significant.
• Notably, antibiotic use and regular daycare attendance before age 6 were not associated with odds of developing MS.