Risk factors for latent tuberculosis infection in children in South Korea

ABSTRACT

Objectives: In South Korea, latent tuberculosis infection (LTBI) screening is a critical strategy associated with efforts to reduce the incidence of tuberculosis (TB). Currently, only children with a known history of TB contact are considered as pediatric high-risk groups for LTBI, and consequently, LTBI screening is only provided to these children. However, to reduce the incidence of TB, the high-risk groups that undergo LTBI screening should be expanded. This study aimed to assess the risk factors for LTBI among children living in South Korea with no known history of TB contact for the identification of additional high-risk groups. We investigated the risk factors for LTBI among US visa applicant children, who undergo LTBI screening regardless of their TB contact history.

Methods: We obtained data on demographic characteristics, medical history, Bacillus Calmette–Guerin (BCG) vaccination history, and results of LTBI screening for children aged 2–14 years. A tuberculin skin test was used for the diagnosis of LTBI, and an induration of 10 mm or greater was used to define a positive test. Adjusted odds ratios and 95% confidence intervals were calculated to determine the association between clinical and demographic variables and LTBI.

Results: Of the 1,664 study participants, 91 (5.5%) had LTBI. The binary logistic regression analysis showed that children born in high TB burden foreign countries had the highest odds of LTBI when considering all the risk factors investigated. Increasing age, absence of BCG vaccination, and a previous diagnosis of asthma were also significant risk factors for LTBI.

Conclusion: These results indicate that children born in high TB burden foreign countries should be considered a high-risk group for LTBI in South Korea; the inclusion of these children in LTBI screening should be considered.

KEYWORDS:

• Latent tuberculosis infection
• risk factor
• children
• foreign born
• asthma
• Bacillus Calmette–Guerin vaccination
• South Korea

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Peer reviewers on this manuscript have no relevant financial relationships to disclose.

Additional information

Funding

This manuscript was not funded.