Trend Analysis And Seasonality Of Tuberculosis Among Patients At The Hiwot Fana Specialized University Hospital, Eastern Ethiopia: A Retrospective Study

Purpose: Tuberculosis (TB) is one of the top 10 leading killer diseases in developing countries, particularly in Sub-Saharan Africa, including Ethiopia. Thus, this study aimed to assess the trend analysis and seasonality of TB at Hiwot Fana Specialized University Hospital, Eastern Ethiopia. Methods and patients: A hospital-based retrospective study was conducted on 8,001 patients by reviewing all available patients' data from January 1, 2015 to April 30, 2019, at the Hiwot Fana Specialized University Hospital, Eastern Ethiopia. Socio-demographic characteristics and results of the GeneXpert assay were taken from the registration book. The data were entered into EpiData 3.1 and analyzed by using the statistical Package for Social Sciences (SPSS) version 20. Results: From a total of 8,001 samples tested using Genexpert, the overall prevalence of Mycobacterium tuberculosis and rifampicin resistance was found to be 1,254 (15.7%) and 53 (4.1%), respectively. A decreasing trend of TB prevalence was observed, and decreased from 19.3% in 2015, 18.6% in 2016, to 18.4% in 2017, 13.5% in 2018 and down to 13.0% in 2019 (P-value<0.001). The maximum number of TB cases were reported during autumn (454, 17.1%) and summer (310, 17.2%) compared to other seasons of all the study period. Being between the ages of 15-29 years (adjusted odds ratio (AOR)=1.7, 95% confidence interval (CI)=1.41-1.98), of male gender (AOR=0.84, 95% CI=0.75-0.96), experiencing a relapse of TB (AOR=0.51, 95% CI=0.35-0.78), and being HIV positive (AOR=0.51, 95% CI=0.3-0.86) were found to be factors associated with high proportion of tuberculosis. Conclusion: Prevalence of TB has decreased year to year between January 2015 and April 2019. However, a high percentage of patients are still testing positive for TB with different seasonal variations. Thus, understanding and managing TB in seasonal variation, controlling relapse of TB, and screening of all HIV positive patients are recommended steps to reduce the transmission of tuberculosis in Ethiopia.