Latent Tuberculosis Infection Prevalence High among Households of TB Patients

A new study from Sri Balaji Vidyapeeth University in Puducherry, India, has found a high prevalence of latent tuberculosis infection (LTBI) among household contacts of tuberculosis (TB) patients. The study aimed to examine variations in LTBI risk factors among first-degree relatives and spouses of TB patients, and identify associated risk factors.

Key Takeaways:

  • LTBI prevalence was 58.1% among 1318 household contacts of 548 TB patients, with 0.5% progressing to active TB.
  • Spouses had a higher LTBI prevalence (64.2%) than first-degree relatives (55.8%), with a significantly elevated risk.
  • Older age (40-59 and 60 years), bed-sharing, female gender, prolonged exposure, undernutrition, overweight/obesity, and alcohol use were linked to higher LTBI prevalence.
  • Female spouses spent more time caring for index cases than male spouses.
  • Spouses had a higher LTBI prevalence than first-degree relatives.
  • Screening programs should prioritize female spouses, undernourished individuals, overweight/obese individuals, and alcohol users to reduce TB transmission.

Statistics:

  • 1,318 household contacts of 548 TB patients were included in the study.
  • The mean age of household contacts was 45.2 (13.7) years, while the mean age of TB patients was 29.5 (16.1) years.
  • 0.5% of LTBI cases progressed to active TB.
  • Spouses had a 1.42 times higher risk of LTBI (95% CI: 1.11-1.83) compared to first-degree relatives.

Sources:

  • Prevalence of Latent Tuberculosis Infection among Spouses and First-Degree Relatives of Pulmonary Tuberculosis Cases in South India. Indian Journal of Public Health, 2025.
  • Wolters Kluwer Medknow Publications, Wolters Kluwer India Pvt Ltd, A-202, 2ND Flr, Qube, C T S No 1498A-2 Village Marol, Andheri East, Mumbai, Maharashtra, India.
  • Data on Pulmonary Tuberculosis Discussed by Researchers at Sri Balaji Vidyapeeth University (Prevalence of Latent Tuberculosis Infection among Spouses and First-Degree Relatives of Pulmonary Tuberculosis Cases in South India). TB & Outbreaks Week. October 21, 2025; p 650.