Tuberculosis in a child – search for the infected adult nearby; case report, Portugal, 2007

Tuberculosis (TB) transmission in a non-household setting is difficult to detect, because contact with the source case is often not obvious. Here, we report on a case of a four-year-old child who got infected through sporadic non-household exposure at a coffee shop. The source case was a woman who had suffered from weight loss, productive cough and fatigue for two months before being diagnosed with TB. Screening the child’s contacts revealed two active TB cases within its family. Overall 148 contacts were screened for both cases and 18 cases of latent TB infection detected. The connection between the child and the source case, who were not aware of their contact, was confirmed by molecular fingerprinting. Our case report illustrates the difficulty in detecting non-household transmission between individuals that do not have significant contact, and draws attention to the need to look for the infected adult whenever a child falls ill with TB. This report is a reminder of the importance to consider possibly neglected ways of TB transmission and highlights once again the need of early diagnosis of TB.