Annual trends of human brucellosis in pastoralist communities of south-western Uganda: a retrospective ten-year study.
BACKGROUND
Human brucellosis is prevalent in both rural and urban Uganda, yet most cases of the disease in humans go unnoticed and untreated because of inaccurate diagnosis, which is often due to the disease not manifesting in any symptoms. This study was undertaken to describe trends in laboratory-confirmed human brucellosis cases at three health facilities in pastoralist communities in South-western, Uganda.


METHODS
Data were collected retrospectively to describe trends of brucellosis over a 10-year period (2003-2012), and supplemented with a prospective study, which was conducted from January to December 2013. Two public health facilities and a private clinic that have diagnostic laboratories were selected for these studies. Annual prevalence was calculated and linearly plotted to observe trends of the disease at the health facilities. A modified Poisson regression model was used to estimate the risk ratio (RR) and 95 % confidence intervals (CIs) to determine the association between brucellosis and independent variables using the robust error variance.


RESULTS
A total of 9,177 persons with suspected brucellosis were identified in the retrospective study, of which 1,318 (14.4 %) were confirmed cases. Brucellosis cases peaked during the months of April and June, as observed in nearly all of the years of the study, while the most noticeable annual increase (11-23 %) was observed from 2010 to 2012. In the prospective study, there were 610 suspected patients at two public health facilities. Of these, 194 (31.8 %) were positive for brucellosis. Respondents aged 45-60 years (RR = 0.50; CI: 0.29-0.84) and those that tested positive for typhoid (RR = 0.68; CI: 0.52-0.89) were less likely to have brucellosis.


CONCLUSIONS
With the noticeable increase in prevalence from 2010 to 2012, diagnosis of both brucellosis and typhoid is important for early detection, and for raising public awareness on methods for preventing brucellosis in this setting.
Department of Health Policy, Planning and Management, School of Public Health, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda. cathie.kansiime@gmail.com.
Catherine
C
Kansiime
Department of Health Policy, Planning and Management, School of Public Health, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda. ellie@musph.ac.ug.
Elizeus
E
Rutebemberwa
Department of Medical Microbiology, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda. basiimwe@chs.mak.ac.ug.
Benon B
BB
Asiimwe
Department of Epidemiology and Biostatistics, School of Public Health, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda. fmakumbi@musph.ac.ug.
Fredrick
F
Makumbi
Department of Microbiology, Mbarara University of Science and Technology, P.O. Box 1410, Mbarara, Uganda. jbazira@gmail.com.
Joel
J
Bazira
Animal Resources and Biosecurity, College of Veterinary Medicine, Makerere University School of Veterinary Medicine, P.O. Box 7062, Kampala, Uganda. mugishaa@yahoo.com.
Anthony
A
Mugisha
D002006:Brucellosis / Q000453:epidemiology* / Q000266:history; D005260:Female; D049674:History, 21st Century; D006801:Humans; D008297:Male; D011159:Population Surveillance; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D012424:Rural Population; D012621:Seasons; D012737:Sex Factors; D014454:Uganda / Q000453:epidemiology