Tuberculosis among children visiting friends & relatives

Area of Science:

• Pediatric infectious diseases
• Public health
• Epidemiology

Background:

• Paediatric tuberculosis (TB) cases in low-incidence countries often involve children from migrant families.
• Visiting friends and relatives (VFR) travel to high-TB-incidence countries is a potential risk factor for TB transmission.
• Estimating the risk of latent TB infection (LTBI) and TB in children undertaking VFR travel is crucial for public health strategies.

Purpose of the Study:

• To estimate the risk of latent TB infection (LTBI) and active TB in children who travelled to their parents' birth country.
• To identify risk factors associated with LTBI in this pediatric population.

Main Methods:

• Prospective, multicentric observational study in Catalonia, Spain (June 2017-December 2019).
• Enrolled children (<15 years) with a parent from a high-TB-incidence country who travelled for ≥21 days.
• Tuberculin skin test (TST) and QuantiFERON-TB Gold Plus (QFT-Plus) performed 8-12 weeks post-return; LTBI defined as TST ≥5 mm and/or positive QFT-Plus.

Main Results:

• 13 out of 500 children (2.6%) were diagnosed with LTBI (16.6/100 person-years of follow-up).
• Two cases (0.4%) of active TB were diagnosed (2.5/100 person-years of follow-up).
• Household tobacco smoke exposure was significantly associated with LTBI (adjusted odds ratio = 3.9).

Conclusions:

• Children undertaking VFR travel to high-TB-incidence countries face a substantial risk of LTBI, potentially exceeding that of the native population.
• Household smoking is a primary risk factor for LTBI in children returning from VFR travel.
• Targeted diagnostic and preventive interventions are recommended for children VFR in high-TB-incidence settings.