Primary tuberculosis infection in 35 children at a Swedish day care center

The decline of tuberculosis (TB) in the Swedish population since the middle of the 20th century resulted in decreased awareness of the disease. Increased migration from TB-endemic countries has resulted in new cases and risk of transmission. A day care provider was diagnosed with cavitary TB after being symptomatic for 5 months. We describe the contact tracing at the day care center, the clinical and radiographic findings, and treatment of the infected children.

We stratified the children by contact with the source case and examined the most exposed first. Thirty-two of 53 attending and 3 of 84 visiting preschool children were infected. All of them had spent at least 3 days at the center. Symptoms were usually mild and nonspecific. Seventeen children had pulmonary radiographic changes compatible with primary TB, and one had miliary TB. The radiographic resolution was slow, with normalization in 50% after 12 months. Eighteen months after termination of treatment, there have been no relapses. The children with latent infection were treated with rifampin for 4 months and none has developed TB.

The manifestations of primary TB in children today are similar to those described 50-70 years ago. The tuberculin skin test is an effective tool for contact tracing in an unvaccinated, previously nonexposed childhood population. Rapid detection of contagious patients and thorough contact investigation remain our most important means to reduce transmission.