https://hdl.handle.net/10646/752 2026-04-09T15:51:22Z https://hdl.handle.net/10646/4607 A survey of Brucellosis and Bovine Tuberculosis at a human-domestic animal-wildlife interface in Zimbabwe. Gadaga, Biko Masimba A cross sectional study was conducted to determine the risk of emergence or the presence and risk factors of bovine tuberculosis and brucellosis in human populations at the human-domestic animal-wildlife interface areas within the South East Lowveld (SEL) of Zimbabwe. A three dimensional risk assessment approach; the release, exposure and consequences assessment was adopted. The release assessment explored the presence or evidence of exposure to Brucella species and Mycobacterium bovis in cattle, milk and meat including game. The exposure assessment investigated disease knowledge and perception by farmers, abattoir and game workers using a structured questionnaire. The consequence assessment analysed human health data collected from health centres in the SEL for tuberculosis, malaria and acute febrile illnesses (AFIs). Three study sites were selected based on the type of domestic animal–wildlife interface: Malipati, Chikombedzi and Chiredzi peri-urban as high, medium and low interface, respectively. This study demonstrated that there was evidence of exposure to brucellosis in cattle, where seroprevalence was highest at the high interface (Malipati) where contact between cattle and wildlife occurs compared to the medium and low interface areas. Bovine tuberculosis was not isolated in cattle. The knowledge, attitude and practices study revealed that 67.4 % (130/193) of the respondents were aware of zoonoses. Fewer cattle owners from a high interface area were aware of zoonoses compared to other areas due to combined effects of limited education and other factors disadvantaging these marginalised areas. This could increase their risk of exposure to zoonoses, considering that consumption of raw meat and milk is common. Analysis of human health data showed that the lack of diagnostic capacity makes estimates of the prevalence of zoonotic TB and the aetiologies of AFIs imprecise and largely unknown. From inference if all cases of extra-pulmonary tuberculosis were treated as M. bovis this would give a prevalence of 4.1%. Noteworthy up to 88% of AFIs cases were not confirmed by laboratory tests. In conclusion, the observed high seroprevalence of brucellosis at the high interface compared to other areas suggested that the interface is a possible nexus for amplification of animal brucellosis. Further, the lack of awareness of zoonoses among farmers, coupled with the presence of risky practices could predispose them to infection by brucellosis. Thus, the contribution of animal derived zoonotic infections to the AFIs observed in the areas could not be ruled out. Therefore, further research is required to determine the public health importance of bovine brucellosis and bTB, and to establish the exact causes of AFIs in these areas. The implementation of brucellosis control measures in these areas could reduce the incidence of brucellosis in cattle and the risk of zoonotic infections. Continued surveillance at abattoirs and slaughter poles by trained animal health personnel would allow early detection of bovine tuberculosis should it arise. 2022-05-18T00:00:00Z https://hdl.handle.net/10646/4606 Seroprevalence and risk factors of brucellosis, chlamydiosis and ehrlichiosis in goats at different wildlife/livestock interface areas in the south-eastern lowveld of Zimbabwe. Bhandi, Solomon Brucellosis and chlamydiosis (zoonotic) are major causes of abortion, still birth, low herd fertility and other reproductive losses in goats in many countries world-wide and ehrlichiosis (heartwater) is also a major threat to livestock, including goat production in sub-Saharan Africa. Three study sites were selected in the south-east lowveld of Zimbabwe; a porous interface site where a direct wildlife/livestock interaction exists, a non-porous interface with no direct wildlife/livestock interaction and a non-interface area where there is little/no chance of wildlife/livestock interaction. Collected goat sera were tested for Brucella spp, Chlamydia abortus and Ehrlichiaruminantium antibodies using the Rose Bengal plate test (RBPT) and the complement fixation (CFT), the CFT and the Major Antigenic Protein (MAP-1B) ELISA tests, respectively. All goats tested (n=563) were negative for Brucella antibodies. Overall, chlamydial seroprevalence was 22% (n=563) while that of ehrlichiosis was 94% (n=450). The prevalence of tick-infestation was 73.3% (n=450). The porous [χ2=9.6, odds ratio (OR) =2.6, p=0.002)] and non-porous (χ2=37.5, OR=5.8, p<0.00001) interfaces were significantly associated with increased chlamydial seropositivity than the non-interface area. In contrast, tick infestation prevalence and ehrlichiosis seroprevalence were not significantly associated (p>0.05) with proximity to wildlife. Female (χ2=49.6, OR=13.6, p<0.0001) and tick-infested (χ2=35.9, OR=8.7, p<0.00001) goats were significantly associated with an increased ehrlichiosis seropositivity compared to their counterparts. Chlamydial seroprevalence was independent of sex (χ2=0.5, OR=1.2, p=0.5), abortion history in female goats (χ2=0.7, OR=1.3, p=0.4), keeping goats with cattle (χ2=0.2, OR=1.5, p=0.7) and flock size (χ2=0.03, OR=1.4, p=0.9). Season was also not associated (p>0.05) with tick-infestation prevalence and ehrlichiosis seroprevalence. The null hypothesis was true with regard to brucellosis and partly true with regards to seroprevalence of chlamydiosis and ehrlichiosis. 2019-01-01T00:00:00Z https://hdl.handle.net/10646/2940 Rabies and rabies-related viruses in Zimbabwe: Historical, virological and ecological aspects Foggin, C. M. Rabies spread rapidly through Zimbabwe after its re-introduction in 1950. Within six years, widespread vaccination of dogs had brought the disease under control. Thereafter, until 1986, there was considerable fluctuation in the occurrence as the epizootics spread into wildlife and cattle. A massive epizootic followed breakdown in rabies control during the civil war in the country. Diagnostic methods in use in the country were shown to have a high degree of accuracy, comparable to that elsewhere. During the period of study, human rabies occurred most commonly as a result of dog bites and conformed to human disease seen elsewhere. Rabies in dogs, jackals and cattle was epizootic in nature and comprised 90 percent of all confirmed cases. The distribution was related to land-use type. Vaccination in dogs showed a negative correlation to the incidence of dog rabies in most provinces; it was estimated that 700 000 dogs should be vaccinated annually by 1990 to control rabies. Jackals were shown to be very susceptible to rabies as well as being efficient vectors, especially to cattle. Rabies vaccine for dogs proved effective in protecting cattle. Surveys revealed no evidence for enzootic rabies in mongooses or jackals, though epizootics in mongooses were prolonged. Examination of rabies virus strains by monoclonal antibodies showed minor differences which were species-specific in mongooses. Rabies vaccines were effective against all the strains tested. The rabies-related Mokola virus was isolated from six cats and a dog which had showed nervous disease. Lagos bat virus was found in one cat. Experimentally, the LD50 for Mokola virus in cats was between 5,0 and 5,7 (logs) mouse intracerebral LD50s. Cats given lower doses showed seroconversion. Virus was present in salivary glands of some cats which died. During surveys, Duvenhage virus was isolated from an insectivorous bat and antibodies to Mokola virus were found in 17,5 percent of gerbils, suggesting that they may act as a reservoir host. These rodents were also shown to be very susceptible to experimental infection. 2017-01-01T00:00:00Z https://hdl.handle.net/10646/1264 The seroprevalence of antibodies to Leptospira species in dogs presented to Harare veterinary clinics and selected rural communities in Zimbabwe Dhliwayo, Solomon A cross sectional study was conducted to investigate the seroprevalence of leptospirosis, and the association between seropositivity and hepatic damage and/or renal insufficiency in dogs from Harare urban and five selected rural areas (Kariba, Machuchuta, Malipati, Marumani and Ndhlovu) in Zimbabwe. The awareness of dog owners on zoonotic importance of canine leptospirosis was also studied using an interviewer-administered structured questionnaire. Sera collected from a randomly selected dogs (both stray and communally- owned) were tested for leptospiral antibodies using an ImmunoComb ELISA kit which detects IgG antibodies to four pooled serovars; L. Canicola, L. Grippotyphosa, L. Icterohaemorrhagiae and L. Pomona. Data was analyzed by calculating proportions positive and assessment of associations using a Chisquared test. Of the 250 samples tested (116 males and 134 females), 39 (15.6%) tested positive for leptospiral IgG antibodies. Overall, urban dogs recorded a significantly (P < 0.05) higher seroprevalence (25%) compared to dogs from rural areas (11.2%). Urban female dogs (P < 0.05) recorded a significantly higher seroprevalence compared to rural female dogs but there was no significant difference between urban male (P > 0.05) and rural male dogs. No significant sex differences were observed in seroprevalence. There was a significant association (P < 0.01) between seropositivity and hepatic damage and/or renal insufficiency with dogs having hepatic damage and/or renal insufficiency being approximately 2 times (RR = 1.96; 1.3 < RR< 3.0) more likely to be seropositive. When asked on their awareness of dog zoonoses, 78.8% (119/151) of dog owners were aware. Of the 78.8% who were aware of zoonoses in dogs, a higher proportion (92.4%) knew rabies as a zoonotic disease in dogs compared to other named zoonoses. Other cited zoonoses were worms (6.7%), leptospirosis (5%), brucellosis (1.7%), ringworm (0.8%) and toxoplasmosis (0.8%). Those who named leptospirosis as a zoonotic disease in dogs were all from the veterinary profession. The results of this study indicated that leptospirosis was present in dogs from the selected areas in Zimbabwe, with a higher seroprevalence in Harare urban areas. Further studies are required to determine the serovars prevalent in these and other areas in the country. Teaching and training programmes for pet owners would improve awareness to leptospirosis and reduce the public health risk of pet zoonoses. 2014-07-17T00:00:00Z