Trends and spatial distribution of animal bites and vaccination status among victims and the animal population, Uganda: A veterinary surveillance system analysis, 2013 – 2017
Authors: Monje Fred , Kadobera Daniel , Ndumu Deo Birungi , Bulage Lilian , Ario Alex Riolexus 
Published: November 2019

Background

Rabies is a vaccine-preventable fatal zoonotic disease. Uganda, through the veterinary surveillance system at National Animal Disease Diagnostics and Epidemiology Centre (NADDEC), captures animal bites (a proxy for rabies) on a monthly basis from districts. We established trends of incidence of animal bites and corresponding post-exposure prophylactic anti-rabies vaccination in humans (PEP), associated mortality rates in humans, spatial distribution of animal bites, and pets vaccinated during 2013-2017.

Methods

We reviewed rabies surveillance data at NADDEC from 2013-2017. The surveillance system captures persons reporting bites by a suspected rabid dog/cat/wild animal, human deaths due to suspected rabies, humans vaccinated against rabies, and pets vaccinated. Number of total pets was obtained from the Uganda Bureau of Statistics. We computed incidence of animal bites and corresponding PEP in humans, and analyzed overall trends, 2013-2017. We also examined human mortality rates and spatial distribution of animal bites/rabies and pets vaccinated against rabies.

Findings

We identified 8,240 persons reporting animal bites in Uganda during 2013-2017; overall incidence of 21 bites/100,000population. The incidence significantly decreased from 8.2/100,000 in 2013 to 1.1/100,000 in 2017 (OR=0.62, p= 0.0074). Of the 8,240 persons with animal bites, 6,799 (82.5%) received PEP, decreasing from 94% in 2013 to 71% in 2017 (OR=0.65, p<0.001). Among 1441 victims, who reportedly never received PEP, 156 (11%) died. Western region had a higher incidence of animal bites (37/100,000) compared to other regions. Only 5.6% (124,555/2,240,000) of all pets in Uganda were vaccinated. There was a decline in the reporting rate of animal bites.

Conclusion

While reported animal bites decreased in Uganda, so did PEP among humans. Very few pets received anti-rabies vaccine. Evaluation of barriers to complete reporting may facilitate interventions to enhance surveillance quality. We recommended improved vaccination of pets against rabies, and immediate administration of exposed humans with PEP.

Author Summary

Rabies is a deadly viral disease, that is transmitted mainly by dog bites. Globally at least 59,000 deaths are reported to occur annually- mostly in Sub-Saharan Africa and Asia. However, rabies can be prevented through vaccination of pets (dogs and cats) and administration of rabies vaccine in humans exposed to rabies. In our study we reviewed secondary data of animal bites and rabies captured at the National Animal disease diagnostic epidemiology centre in Entebbe for the period 2013-2017. We found that of 1441 animal bite victims who never received rabies vaccine, only 156 (11%) died hence need for immediate administration of exposed humans with rabies and sensitization of the public about the consequences of animal bites and need for urgent health care. There was a decline in the reporting rate of animal bites during the study period suggesting that evaluation of the barriers to complete reporting may facilitate interventions to enhance surveillance quality. Less than 10% of the pets in the Uganda were vaccinated against rabies hence need for improved vaccination of pets against rabies through appropriated legislation.