Prevalence and risk factors of active TB disease in contacts of TB cases in Nigeria

Who

• Index cases: Patients diagnosed with active tuberculosis (TB) disease attending the Chest/TB clinic of Chukwuemeka Odumegwu Ojukwu University Teaching Hospital.

  • Modal age group: 36–45 years

  • Mean age: 40.49 years

  • Predominantly male

  • 99.2% had pulmonary TB

  • 82.6% were smear-positive

  • 28.1% were HIV-positive

• Contacts: Individuals identified through index cases, predominantly household contacts.

  • Modal age group: ≤15 years

  • Mean age: 24.01 years

  • Predominantly female

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What

• Study focus: Determination of the prevalence and risk factors of active TB disease among contacts of patients with active TB.

• Key findings:

  • 17.5% of contacts had at least one symptom suggestive of TB.

  • Active TB disease was detected in 2.7% of contacts.

  • Presence of TB symptoms among contacts was significantly associated with active TB disease (p = 0.000).

• Conclusion: Contacts of active TB patients have a higher risk of developing active TB compared to the general population. Systematic contact investigation is crucial for early case detection and TB control.

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When

• Not specified.

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Where

• Chest/TB clinic of Chukwuemeka Odumegwu Ojukwu University Teaching Hospital, Awka, southeastern Nigeria.

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Why

• To address the increased risk of active TB disease among contacts of TB patients and to support TB control efforts through early identification of previously undiagnosed cases, particularly in high TB burden settings.

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How

• Study design: Cross-sectional study.

• Sampling: Consecutive enrollment of all diagnosed active TB patients and their identified contacts.

• Data collection:

  • In-depth interviews with index cases to identify contacts.

  • Interviewer-administered questionnaires for both index cases and contacts.

• Screening and diagnosis:

• Clinical screening of contacts for cardinal TB symptoms (e.g., prolonged cough, fever, weight loss, night sweats; failure to thrive in children).

• Laboratory testing using Xpert MTB/RIF Ultra assay on sputum samples (adults) or stool samples (children unable to produce sputum).

Source: Njelita, I.A., Nwachukwu, C.C., Eyisi, I.G., Ezenyeaku, C.A. and Okeke, H.N., 2025. Prevalence and risk factors of active tuberculosis disease in contacts of tuberculosis cases treated in a teaching hospital in southeast Nigeria: a cross-sectional study. International Journal of Healthcare Sciences, 13(1), pp.80-89.