Mapping of Mycobacterium tuberculosis cases in post-conflict Liberia, 2008-2012: A descriptive and categorical analysis of age, gender and seasonal pattern.

ABSTRACT

BACKGROUND: Tuberculosis (TB) is a major public health. problem in Liberia and it is among the first five most important infectious diseases. Fourteen years of civil war in Liberia caused a large internal displacement and external migration of its citizens to neighbouring countries such as Guinea, Ivory Coast, Sierra Leone, Ghana and Nigeria. Current spatio-temporal pattern of TB cases in Liberia is essential for identifying risk factors among humans for optimal resource allocation. METHODS: Surveillance data from January, 2008 to December, 2012 were retrieved from two national TB referral hospitals in the country TB Annex Hospital (TBAH) (Montserrado County) and Ganta TB and Leprosy Rehabilitation Hospital (GTBLRH) (Nimba County). Geographic coordinates of TB patient's locations were captured based on records in the hospital case-files using Global Positioning System (GPS). The coordinates were mapped using Geographic Information Systems (GIS) software. Data on age, gender, date of illness, dry and wet season frequency were used to compute a descriptive and categorical analysis. Kulldorff's spatio-temporal scan statistic was used to identify clusters of TB in the two Counties. RESULTS: A total of 2,890 laboratory-confirmed cases were reported during the study period. There were 1,365 (47.23%) and 1,525 (52.77%) cases from TBAH and GTBLRH respectively. The mean age of patient was 45.19 years ± 19.49 (SD). Of this, 1,450 (50.17%) were male. There was significant association between year of TB occurrence and treatment outcome (χ2 = 14.38; p = 0.006). CONCLUSION: The paper presents TB spatial pattern, summarizing 5-year records of post-conflict surveillance of the disease in Liberia.