Assessment of Environmental Factors Influencing Tuberculosis Transmission in Crowded Urban Settings in Kano, North West Nigeria

Tuberculosis (TB) remains a significant public health burden in Nigeria, with environmental conditions such as overcrowding, poor ventilation, and inadequate housing substantially influencing transmission dynamics. This cross-sectional study assessed environmental factors associated with tuberculosis transmission in crowded urban neighborhoods in Kano Municipal Local Government Area, North West Nigeria. A case-control design was employed, with 150 confirmed TB cases matched with 300 non-TB controls from the same neighborhoods. Environmental variables including housing density, ventilation adequacy, floor area per occupant, and proximity to TB cases were assessed through household visits. Spirometric screening and sputum microscopy data from community health centers were reviewed. Results demonstrated that living in homes with fewer than four square metres of floor area per occupant was associated with a threefold increased odds of TB diagnosis. Inadequate cross-ventilation was documented in eighty-two percent of TB case households. History of living with a smear-positive TB patient was the strongest individual risk factor, with an odds ratio of 8.3. Malnutrition, evidenced by low body mass index, was more prevalent among cases and served as a significant cofactor. The study recommends housing improvement interventions, targeted ventilation upgrades in high-density areas, active case finding in TB household contacts, and integration of environmental health strategies into the Kano State TB control program. Keywords: tuberculosis, environmental factors, housing, ventilation, Kano.