Long term trends and geographical distribution of animal bite injuries and deaths due to human rabies infection: Analysis of 2001-2015 epidemiological surveillance data in Uganda.

Authors: Ben Masiira1, Issa Makumbi2, Joseph Matovu2, Immaculate Nabukenya3, Frank Kaharuza2, Christine Kihembo1, Alex R. Ario1; Affiliations: 1Public Health Fellowship Program, 2Makerere school of Public Health, 3Ministry of Health

Summary: In absence of accurate data on trends and burden of human rabies infection in developing countries, animal bite injuries provide useful information to bridge that gap. Rabies is one of the most deadly infectious diseases, with a case fatality rate approaching 100%. We describe trends and geographical distribution of animal bite injuries, a proxy of human rabies, and deaths due to suspected human rabies in Uganda from 2001 to 2015. A total of 208,720 cases of animal bites were treated at health facilities in Uganda; Central region 27%, Eastern region 22%, 27% in Northern region and 23% in Western region. Of the 48,720 bites treated from 2013 – 2015, 59% were among males; 19% were children ≤5 years. Overall incidence was 58.1 per 100,000 with a significant


                              Introduction.

The burden and trends of human rabies infection in developing countries is poorly understood due to limited diagnostic capacity and lack of accurate data. Animal bites injuries in humans provide an important source of epidemiological information which is crucial in detecting trends in rabies incidence and enhancing surveillance systems.. Despite of availability of effective post exposure vaccine treatment, rabies is estimated to kill 50,000 to 60,000 people worldwide each year and it was responsible for 1,460,000 Disability Adjusted Life Years in 2010.. Canine rabies has been eliminated in most off the western world but still remains an under-reported public health problem in the African region.. The African region also faces a challenge of paucity of information about human rabies infection yet this is essential in planning and implementation of effective control strategies. We describe trends and geographical distribution of animal bite injuries and suspected rabies deaths in Uganda using weekly epidemiological surveillance (health management information system) data collected between 2001 and 2015.
We used maps to describe geographical distribution of rabies cases by district

                                   Results.
A total of 208,720 cases of animal bites were reported during the study period of which 27% (n=57,252) were in Central region, 22% (n=46,742) in Eastern region, 27% (n=56,382) in Northern region and 23% (n=48,344) in Western region. Out of 48,720 animal bite injuries treated at health facilities between 2013 and 2015, 59% were inflicted on males and 19% were children aged below 5 years. The overall incidence of animal bites in Uganda was 58.1 per 100,000. The incidence (per 100,000 population) of animal bites by region was 78 in Northern region, 58 in Central region, 53 in Western region and 50 in East- ern region. The incidence of animal bites increased from 21 to 47 (p<0.001) in Central region, 27 to 34 (p<0.001) in Eastern region, 23 to 70 (p<0.001) in Northern region and 16 to 46  (p<0.001) in Western region (Figure 1). A total of 457 suspected human rabies deaths were reported from health facilities, of which 29% were reported from Eastern region, 27% from Northern region, 27% from Central region and 17% from West region. The highest incidence was observed in the districts of Wakiso, Kabarole, Kotido and Moroto. Many of districts in Northern Uganda had higher incidence of animal bite injuries compared to districts in other regions (Figure 2).

Fig1: Trends of incidence (per 100,000) of animal bites injuries by region; 2001-2015.
Fig2: Geographical distribution of animal bites by district; 2001-2015

Discussion and Recommendations.


This study provides evidence of a high burden of animal bite injuries in Uganda. The finding that most of the animal bite injuries in our study were inflicted on males is consistent with results reported from other studies conducted elsewhere (6, 7). Gender differences in the distribution of animal bites are possibly related to occupational activities that expose individuals to dog bites and such activities are more common among males compared to females (8). Variations in the incidence of animal bites across different regions are likely to be due to different dog populations in different districts. The northern region which had the highest incidence of animal bites had the highest dog population during the animal Census of 2008 (9). Additionally, regional geographical differences, population density and possible differences in local epidemiology of rabies may explain variations in incidence of animal bites (10). This study found that the number of deaths due to suspected rabies was higher than the 20 deaths estimated in 2005 (11). The number of suspected deaths due to rabies significantly increased only in the Central region. Increase in incidence of animal bites in all regions of Uganda implies that rabies remains an important public health challenge that requires special attention during planning of national health priorities. There is need to strengthen rabies community sensitization and improve rabies surveillance in order to collect more reliable information that can effectively guide public health interventions.

References.
1.Cleaveland S, Fevre EM, Kaare M, Coleman PG. Estimating human rabies mortality in the United 
Republic of Tanzania from dog bite injuries. Bulletin of the World Health Organization. 2002; 80 
(4):304-10.

2. Belotto A LL, Schneider MC, Tamayo H, Correa E. Overview of rabies in the Americas. Virus Res 
2005;111(1):5-12.

3. Hotez PJ, Alvarado M, Basanez MG, Bolliger I, Bourne R, Boussinesq M, et al. The global burden of 
disease study 2010: interpretation and implications for the neglected tropical diseases. PLoS 
neglected tropical diseases. 2014;8(7).

4. Dodet B, Adjogoua EV, Aguemon AR, Baba BA, Bara Adda S, Boumandouki P, et al. [The fight against 
rabies in Africa: from recognition to action]. Bulletin de la Societe de pathologie exotique (1990). 
2010;103(1):51-9.

5. World Health Organization. WHO Expert Consultation on Rabies, 2013. Second report.

6. Lai P, Rawat A, Sagar A, Tiwari K. Prevalence of dog-bites in Delhi: knowledge and practices of 
residents regarding prevention and control of rabies. Health and Population perspectives and Issues. 
2005;28(2):50-7.

7. MAJID REZA ERFANIAN TAGHVAII AND SEYED MOHSEN SEYEDNOZADI. An Epidemiologic Survey on Animal Bite 
Cases Referred to Health Cen- ters in Mashhad During 2006 to 2009. Biomedical & Pharmacology Journal. 
2013;6 (2):301-6.
8. Uganda Bureau of Statistics. THE NATIONAL LIVESTOCK CENSUS REPORT 2008.

9. Tenzin, Dhand NK, Gyeltshen T, Firestone S, Zangmo C, Dema C, et al. Dog bites in humans and 
estimating human rabies mortality in rabies endemic areas of Bhutan. PLoS neglected tropical 
diseases. 2011;5(11).

10. Fevre EM, Kaboyo RW, Persson V, Edelsten M, Coleman PG, Cleaveland S. The epidemiology of animal 
bite injuries in Uganda and projections of the burden of rabies. Tropical medicine & international 
health : TM & IH. 2005;10(8):790-8.