Level and pattern of human rabies and dog bites in Techiman Municipality in the Middle Belt of Ghana: a six year retrospective records review

Introduction Rabies is a viral zoonotic disease that is transmitted primarily by bites from rabid dogs and has the highest case fatality rate of most infectious diseases in humans. We described a 6-year trend of rabies and dog bites in a peri-urban district in Ghana. Methods A record review was conducted in the health facilities in Techiman to identify all human rabies and dog bite cases reported from January 2011 to December 2016. Rabies and dog bite data were extracted from health facilities records. Vaccination status of implicated dogs was extracted from the veterinary records at the Techiman Disease Investigation Farm. Data were summarized using proportions and presented using tables, charts and figures. Results Thirteen (13) cases of human rabies were recorded from 2011 to 2016. Complete data was available for 10 cases. Median age of rabies victims was 30 (range 3-80 years). A majority were males (8 representing 61.5%). Eight cases came from rural farming communities, 8 had a previous history of dog bite ranging from two weeks to five months before the onset of rabies symptoms and one reported with non-bite rabies. Case fatality was 100%. A total of 680 dog bites were reported by health facilities. About 50.3% (342) of the victims were males, a majority of bites (47.9%) occurred among children aged 1-15 years. Positive rabies cases among offending dogs ranged from 3.3% in 2016 to 17.6% in 2014. Conclusion Mass vaccination of dogs and provision of post-exposure vaccination are needed to reduce rabies transmission.


Introduction
Rabies is a zoonotic disease caused by Lyssavirus from the family Rhabdoviridae. Domestic and wild animals are mostly vulnerable to rabies infection, but the disease is transmitted to humans through bites or scratches from these animals [1]. The rabies virus infects the central nervous system, causing disease in the brain which eventually leads to death. Among unvaccinated population rabies is almost always fatal if post-exposure prophylaxis is not administered before the onset of symptoms [2,3]. Globally mortality resulting from rabies is estimated between 40,000-70,000 deaths annually, with nearly all deaths occurring in developing countries [4]. These potentially preventable deaths, occur in Africa and Asia where animal control, vaccination programs and post exposure prophylaxis are not universal [1]. The domestic dog is an important vector in the transmission of human rabies, contributing about 97% of all rabies related deaths in humans worldwide [5,6].
The disease occurs commonly in rural farming communities where measures to prevent dog to human transmission have been poorly implemented [7]. Wound cleansing within a few hours after bites from suspected rabid animal can prevent the onset of rabies and death. Every year, about 15 million people worldwide receive post exposure preventive regimen to prevent rabies at an annual cost of $58 3.5m but most beneficiaries live in developed countries [8]. For many decades now, rabies has been occurring among human population in Ghana. Between 2000 and 2004 alone, there were about 123 clinically confirmed human rabies cases reported by public health facilities across the country [9]. In 2009, an outbreak of rabies in dog and human population in three communities in Bongo District of Upper East region and one border community in Burkina claimed nine lives [10]. However, human rabies cases in Ghana are generally under reported because of weak surveillance system, poor laboratory support and unhealthy socio-cultural factors. Secondly, while majority of human rabies cases are caused by exposure to dog bites [6], information on these bites is limited in the country, making it difficult for effective public health planning in addressing the menace of human rabies in the country. Hospital records revealed that between 2009 and 2012 there were 546 reported cases of dog bites and five cases of rabies in Techiman Municipality [11]. With ever increasing population density and the need for domestic dogs for security and economic reasons in this peri-urban municipality, dog bites and human rabies cases are believed to be on the increase. The need for proper documentation of this trend to inform public health actions on the disease in this geographic area is urgent. We conducted a six year retrospective records review of dog bites and rabies cases reported at health facilities from 2011-2016 to document the trend and the management of these cases in Techiman municipality.

Profile of techiman:
Techiman municipal assembly is located in the savanna transitional ecological zone in the middle belt of Ghana.
It is one of the 27 administrative districts in Brong Ahafo region of the country. The municipality is situated in the central part of the region and lies between longitude 1049'and 2030' west and latitude 8000' north and 7035' south and has annual rainfall between 1,260mm to 1,660mm. It is boarded to the north by Wenchi and Techiman north districts, to the south by Sunyani municipality and Offinso north district, to the west by Tain district and to the east by Nkoranza south [12]. It has a total land surface area of 669.7sqkm with a climate and vegetation that promotes agricultural activities.

Methods
The investigation was carried out from 11 th January, 2017 to 23 rd March, 2017. It involved review of medical records and interview with health providers within the municipality. We A contact was made with regional pharmacist to understand the supply chain issues with anti-rabies vaccine. Rabies is clinically diagnosed when person who is suspected to have had a contact with a rabid animal develops one or more of the following: headache, neck pain, nausea, fever, fear of water, anxiety, agitation, abnormal tingling sensations or pain at the wound site. A suspected case of rabies is confirmed in laboratory by detection of viral antigens using direct florescent antibody test of brain tissue. This is not routinely done in the study country. For the purpose of this study, we defined human rabies as any case that a clinician diagnosed as such. A bite was defined as suspected if the dog bit a human without any provocation, if the dog was wild or not vaccinated and if it died or escaped after the bite [13]. An animal was confirmed as having rabies if the Sellar stains on the brain tissues showed the presence of nigre bodies at Techiman disease investigation Farm or if a suspected rabies dog could not be traced for investigation. Data was analyzed in excel and summarized as proportions and presented in tables and figures (graphs).

Results
We interviewed 13 health and Agricultural workers comprising 3 medical doctors, 2 physician assistants, 2 nurses, 3 pharmacists, 1 veterinary doctor and 2 technical officers in disease control. Median age of staff was 46 years (minimum 34 and maximum 58 years) and median years of experience 17 (minimum 4 and maximum 28 years). Nine health facilities were visited. In all, 13 cases of human rabies were recorded at the Holy Family Hospital from 2011 to 2016.
Demographic data was available for only ten of the cases. Median age of rabies victims was 30 (range 3-80 years). Majority were males (6 representing 60%). Of the 10 cases for which data was available, 8 came from rural farming communities. No two cases came from the same community. Most of the cases were recorded in 2012 (4 cases) and 2014 (4 cases). 8 of the cases had a previous history of dog bite ranging from two weeks to five months before onset of rabies symptoms. Only one reported with non-bite rabies (consumption of rabies dog) and history of exposure was unavailable for 1. Case fatality was 100%. Of the 8 that had history of dog bites, 6 were domestic bites while 2 were stray dog bites. No information was available on the vaccination/or rabid status of the dogs. Table 1 (Table 1). Table 2   in town. This is because the regional medical store which supplied health facilities with these important vaccines had not received antirabies vaccine since the central medical stores was gutted by fire in early 2015 (Regional pharmacist). None of the pharmacy shops (4) that sold vaccines had temperature monitoring charts in the vaccine fridges. Vaccines were often sold to patients packaged in envelops instead of cold chain boxes.

Discussion
Our study recorded 13 cases of human rabies diagnosed clinically in Techiman municipality over the period with 100% case fatality. We believe that these numbers may actually represent a gross underreporting of the true magnitude of the problem in our study area.
Rabies commonly manifest clinically with symptoms of mental illness. Anecdotal observations show that the first point of care for people with neuro-psychiatric conditions in our study area is herbalists and spiritual healers where data is not routinely captured by the health system. It could partly be because some cases that presented at the health facilities could have been mis-diagnosed as meningitis or encephalitis while many others could have died in the communities [5]. However, our findings are consistent with other findings in parts of Africa, highlighting rabies as a serious public health problem [5,6,14] that requires attention. Most of the deaths from our study came from rural communities. Also, Majority involved male victims. This is consistent with other studies in Africa where human fatalities occur mostly among individuals in rural farming communities with limited access to resources for proper health care [6]. Men are commonly affected by rabies because they often work outdoors during farming and hunting expeditions and therefore come into contact with strayed dogs compared to women who often work indoor in rural areas. Children less than 15 years had the highest exposure to suspected rabies dog bites. This could be due to the fact that children by nature are more likely to provoke dogs, yet they cannot defend themselves. This finding is consistent with studies carried out in Tanzania and Ethiopia [15,16]. However, another study in New York found no significant difference among sex or age distribution and rabies bite exposure [17], but is in a setting with different pet control program.
In this study, 8 of the 10 cases with information had been bitten by dogs prior to presentation, 1 had handled or eaten a rabid dog and for 1 no history was given. Similar observations were found in other studies where domestic dog bites were responsible for over 94% of human rabies cases [18][19][20]. Transmission of rabies from non-bite source is rare but it is believed to occur when saliva or brain tissue gets into the eyes, nose, mouth or wounds from scratches, aberrations or open wounds of individuals [21]. In our case, the person was involved in carrying and preparing of meat of a dog that had displayed symptoms of rabies before death and might have been contaminated with the virus through any of the above routes.
Of the suspected rabies dog bites that were referred to the veterinary department for investigation, between 3.3-17.6% tested positive for rabies. This result is far higher than the incidence of rabies among dog bites reported in Ethiopia [22]. Moreover, the test used to diagnose rabies in our study was the microscopic examination by Seller's stain test (SST) for Negri bodies. However, this test has low sensitivity when compared with direct fluorescent antibody test (dFAT) [23,24] implying that the result could have Page number not for citation purposes 5 under-estimated the real situation. This poses a major risk of continuous transmission of the disease to human population in the municipality. The situation has also brought to the fore, the challenges facing rabies control in the country and calls for urgent laboratory support in the fight against transmission of rabies. In our study, incidence of rabies among dogs correlates positively with incidence among humans. Because of the role that domestic dogs play in the transmission of rabies to humans, regular anti-rabies vaccination of dogs could help control transmission of the disease to humans. Less than 35% of the offending dogs were vaccinated.
This level of coverage is not adequate to prevent transmission of rabies. Vaccination of dogs is one single most important intervention used to control rabies [25]. For example, routine vaccination of dogs was used to eliminate canine rabies in Western Europe and North America [26,27]. Annual vaccination coverage of 70% in domestic dogs is recommended for effective control of the disease [28,29].
In our study area, routine vaccination campaigns are organized annually for pet owners but patronage has been poor. This is because Ghana currently does not have an enforceable policy on pet vaccination and coupled with low awareness of the dangers of rabies among the populace makes it unattractive for pet owners to have them vaccinated. We found in our study that only 1 out of the 9 health facilities that were visited during the study period had