Prevalence of BCG scar among vaccinated children and its correlation with Mantoux skin test at Omdawanban area, Sudan.

PURPOSE: Tuberculosis (TB) remains a significant public health concern globally. Bacille Calmette-Guérin (BCG) vaccination is widely used, but scar formation post-vaccination is not universal, which raises concerns about its efficacy. The Mantoux test is used to assess the immune response following BCG vaccination. This study aims to evaluate the prevalence of BCG scar formation among vaccinated children and its correlation with Mantoux test reactions.

METHODS

This quantitative, cross-sectional descriptive study was conducted among children aged 3 months to 9 years at the vaccination office in Omdawanban, Sudan, from September to October 2021. Data were collected using structured surveys and the Mantoux skin test.

RESULTS

Out of 350 vaccinated children, 285 (81.4 %) exhibited a visible BCG scar, while 65 (18.6 %) did not. Mantoux test positivity was observed in 132 children (37.7 %). A significant association was found between the presence of a BCG scar and a positive Mantoux test result (p < 0.05), with 39.3 % of children with a visible scar showing positive Mantoux results compared to 30.8 % of children without a scar. The likelihood of a positive Mantoux test was 3.2 times higher in children with a visible BCG scar (OR = 3.2, 95 % CI [1.8-5.8]). Mantoux positivity also varied by age, with the highest rate (41.2 %) observed among children aged 5-9 years (p = 0.03).

CONCLUSIONS

There is a significant association between BCG scar formation and Mantoux test positivity. Improved training for healthcare workers and better education for mothers about vaccination are recommended.