Wassie Molla

Incidence of Rabies in Humans and Domestic Animals and People's Awareness in North Gondar Zone, Ethiopia

Background Rabies is a zoonotic disease that has been prevalent in humans and animals for centuries in Ethiopia and it is often dealt with using traditional practices. There is lack of accurate quantitative information on rabies both in humans and animals in Ethiopia and little is known about the awareness of the people about the disease. In this study, we estimated the incidence of rabies in humans and domestic animals, and assessed the peoples awareness about the disease in North Gondar zone, Ethiopia. Methodology/Principal Findings The incidence of rabies in humans and domestic animals was prospectively followed up for one year period based on clinical observation. A questionnaire was also administered to 120 randomly selected dog owners and 5 traditional healers to assess the knowledge and practices about the disease. We found an annual estimated rabies incidence of 2.33 cases per 100,000 in humans, 412.83 cases per 100,000 in dogs, 19.89 cases per 100,000 in cattle, 67.68 cases per 100,000 in equines, and 14.45 cases per 100,000 in goats. Dog bite was the source of infection for all fatal rabies cases. Ninety eight percent of the questionnaire respondents were familiar with rabies and mentioned dog bite as a means of transmission. But discordant with current scientific knowledge, 84% and 32% of the respondents respectively mentioned any type of contact (irrespective of skin condition) with saliva, and inhalation as a means of transmission of rabies. Eighty four percent of the respondents relied on traditional healers for management of rabies. Conclusions The study shows high canine rabies burden, and lack of sufficient awareness about the disease and high reliance on traditional treatment that interfere with timely post exposure management. Vaccination of dogs, proper post exposure management, and increasing the awareness of the community are suggested to reduce the disease burden.

Occurrence and antimicrobial resistance of Salmonella serovars in apparently healthy slaughtered sheep and goats of central Ethiopia

The present study was undertaken to determine the occurrence, distribution and antimicrobial resistance pattern of Salmonella serovars in apparently healthy slaughtered sheep and goats in central Ethiopia. A total 1224 samples consisting of faeces, mesenteric lymph nodes, liver, spleen, and abdominal and diaphragmatic muscle samples were collected from 104 sheep and 100 goats. Salmonella was isolated from 12 of 104 (11.5%) sheep and 3 of 100 (3%) goats. Of the total 624 and 600 samples examined from sheep and goats, 18 (2.9%) and 4 (0.7%), respectively, were Salmonella positive. The 22 Salmonella isolates belonged to 9 different serovars. The common serovars isolated were S.typhimurium, followed by S.heidelberg, S.reading, S.give, and S.poona. Seven of the 22 isolates (31.8%) were multidrug-resistant to various antimicrobials.

Economic impact of lumpy skin disease and cost effectiveness of vaccination for the control of outbreaks in Ethiopia

Lumpy skin disease (LSD), an infectious viral disease of cattle, causes considerable financial losses in livestock industry of affected countries. A questionnaire survey with the objectives of determining direct economic losses of LSD (mortality loss, milk loss, draft loss) and treatment costs (medication and labour cost) per affected herd, and assessing the cost effectiveness of vaccination as a means for LSD control was carried out in the central and north-western parts of Ethiopia. From a total of 4430 cattle (in 243 herds) surveyed, 941 animals (in 200 herds) were reported to be infected. The overall morbidity and mortality at animal level were 21.2% and 4.5%, and at herd level these were 82.3% and 24.3%. There was a significant difference in animal level morbidity and mortality between categories of animals. Over 94% of the herd owners ranked LSD as a big or very big problem for cattle production. A large proportion (92.2%) of the herd owners indicated that LSD affects cattle marketing. A median loss of USD 375 (USD 325 in local Zebu and USD 1250 in Holstein-Friesian local Zebu cross cattle) was estimated per dead animal. Median losses per affected lactating cow were USD 141 (USD 63 in local Zebu cows and USD 216 in Holstein-Friesian local Zebu cross cows) and, USD 36 per affected ox. Diagnosis and medication cost per affected animal were estimated at USD 5. The median total economic loss of an LSD outbreak at herd level was USD 1176 (USD 489 in subsistence farm and USD 2735 in commercial farm). At herd level, the largest component of the economic loss was due to mortality (USD 1000) followed by milk loss (USD 120). LSD control costs were the least contributor to herd level losses. The total herd level economic losses in the commercial farm type were significantly higher than in the subsistence farm type. The financial analysis showed a positive net profit of USD 136 (USD 56 for subsistence farm herds and USD 283 for commercial herds) per herd due to LSD vaccine investment. It should be noted that only the noticeable direct costs and treatment costs associated with the disease were considered in the study. Generally, vaccination is economically effective and should be encouraged.

Seroprevalence and risk factors of lumpy skin disease in Ethiopia

Lumpy skin disease (LSD) is an acute or inapparent viral disease of cattle which is endemic in many African and Middle East countries. LSD is one of the major transboundary livestock diseases in Ethiopia. A cross-sectional study using multistage cluster sampling was undertaken in central and north-western parts of Ethiopia with the objectives to estimate seroprevalence and to identify and quantify risk factors contributing to the occurrence of the disease. A total of 2386 cattle sera were sampled from 605 herds and 30 clusters (kebeles) located in 10 districts and tested for presence of LSD virus antibodies using virus neutralization test. All the serum samples were collected from cattle having no history of LSD vaccination. The overall animal level and herd level apparent seroprevalences were 25.4% (95% CI: 23.7-27.2) and 48.9% (95% CI: 44.9-52.9), respectively and varied significantly between districts. The true animal level and herd level prevalences were estimated as 26.5% (95% CI: 24.7-28.3) and 52.6% (95% CI: 48.3-56.9), respectively. At animal level, adult age (OR = 2.44 (95% CI: 1.67-3.55) compared to calf), contact with other animals (OR = 0.41 (95% CI: 0.23-0.74), compared to no contact) and presence of water bodies (OR = 1.61 (95% CI: 1.03-2.52), compared to no such bodies) were identified as the most important risk factors in relation to testing LSD positive. The putative risk factors altitude, breed, sex, and presence of animal trade route showed no significant association with LSD sero-status. Generally, cattle population with many adult animals and that live in wet areas are at highest risk, whereas cattle in frequent contact with other animals and animal species have lower risk, potentially due to a dilution effect of vectors.

Sero-epidemiological study of peste des petits ruminants in small ruminants in Amahara region, Ethiopia

Peste des petits ruminants (PPR) is an acute, highly contagious, and economically important transboundary viral disease of sheep and goats. It is among the major infectious diseases that affect the production and productivity of small ruminants in Ethiopia. Cross-sectional and retrospective studies were undertaken to estimate the sero-prevalence, risk factors, and distribution of PPR in Amhara region. A total of 672 (329 sheep and 343 goats) sera were collected from 30 kebeles in 10 districts. Of the 672 sheep and goat sera samples tested using c-ELISA, 123 were positive for PPR antibodies, with the overall prevalence of 18.30% (95%CI 15.37, 21.24). The sero-prevalence of PPR was 21.57% (95%CI 17.15, 25.86) in goats and 14.89% (95%CI 10.96–18.65) in sheep. The variation of sero-prevalence among study zones was statistically significant (p < 0.05). The highest sero-prevalence was reported in Awi zone (55.34%) followed by South Gondar (15.89%), North Gondar (13.64%), East Gojjam (7.93%), and West Gojjam (6.62%) zones. Among host- and environment-related risk factors, species, sex, agro-ecology, and location of the study were significantly associated with PPR sero-positivity. The analysis of 5-year retrospective data (2010–2014) revealed high occurrence of PPR in the Amhara region with a total occurrence of 63 outbreaks (3978 cases and 919 deaths). In conclusion, the study revealed that PPR is an important and widely distributed disease of small ruminants in Amhara region. Appropriate control strategy including regular surveillance and vaccination is recommended to mitigate the challenge of PPR.

Molecular identification and investigations of contagious ecthyma (Orf virus) in small ruminants, North west Ethiopia

BackgroundOrf virus, the prototype of parapoxvirus, is the main causative agent of contagious ecthyma. Little is known about the status of the disease in Ethiopia and this study was aimed at determining its status using PCR as a confirmatory tool.Methodsa total of 400 randomly selected sheep and goat was screened for the identification of the virus using amplification of B2L gene and transfection of mammalian cells (VERO cells).ResultsOut of 400 animals screened for infection of the virus, 48 animals were found positive to PCR and revealed an overall incidence of 12%. Different epidemiological parameters were considered to look at the association with incidence of the disease and of which, only species of the animal(sheep), non-vaccinated and non-treated animals, nursing animals, poor body condition animals, extensively managed animals, animals having mouth lesion, and study areas having outbreak history showed higher prevalence. A univariate logistic regression analysis showed statistically significant difference in all variables (P < 0.05). Whereas, age and sex of animals showed no significant difference (P < 0.05).ConclusionThe result of the present finding showed high incidence of Orf virus in the region as confirmed through PCR.

Field study on the use of vaccination to control the occurrence of lumpy skin disease in Ethiopian cattle

The current study was carried out in central and North-western parts of Ethiopia to assess the efficacy of Kenyan sheep pox virus strain vaccine (KS1 O-180) against natural lumpy skin disease (LSD) infection under field conditions by estimating its effect on the transmission and severity of the disease. For this study, an LSD outbreak was defined as the occurrence of at least one LSD case in a specified geographical area. An observational study was conducted on a total of 2053 (1304 vaccinated and 749 unvaccinated) cattle in 339 infected herds located in 10 sub-kebeles and a questionnaire survey was administered to 224 herd owners. Over 60% of the herd owners reported that the vaccine has a low to very low effect in protecting animals against clinical LSD; almost all of them indicated that the vaccine did not induce any adverse reactions. In the unvaccinated group of animals 31.1% were diagnosed with LSD while this was 22.5% in the vaccinated group (P<0.001). Severity of the disease was significantly reduced in vaccinated compared to unvaccinated animals (OR=0.68, 95% CI: 0.49; 0.96). Unvaccinated infected animals were more likely (predicted fraction=0.89) to develop moderate and severe disease than vaccinated infected animals (predicted fraction=0.84). LSD vaccine efficacy for susceptibility was estimated to be 0.46 (i.e. a susceptibility effect of 0.54) while the infectiousness effect of the vaccine was 1.83. In other words, the vaccine reduces the susceptibility by a factor of two and increases infectiousness by approximately the same amount. LSD transmission occurred in both vaccinated and unvaccinated animals, the estimated reproduction ratio (R) was 1.21 in unvaccinated animals compared to 1.19 in vaccinated ones, and not significantly different. In conclusion, KS1 O-180 vaccination, as applied currently in Ethiopia, has poor efficacy in protecting cattle populations against LSD, neither by direct clinical protection nor by reducing transmission, and this signifies the urgent need to either improve the quality of the vaccine or to develop potent alternative vaccines that will confer good protection against LSD.

Sero-prevalence, risk factors and distribution of sheep and goat pox in Amhara Region, Ethiopia

BackgroundSheep pox and goat pox are contagious viral diseases of sheep and goats, respectively. The diseases result in substantial economic losses due to decreased milk and meat production, damage to hides and wool, and possible trade restriction. A study was undertaken in Amhara region of Ethiopia. A cross-sectional study design was used to estimate the sero-prevalence and identify associated risk factors, while retrospective study design was used to assess the temporal and spatial distribution of the disease. A total of 672 serum samples were collected from 30 Kebeles and tested using virus neutralization test.ResultsFrom a total of 672 sera tested, 104 (15.5%) were positive for sheep and goat pox virus antibody; from which 56 (17%) were sheep and 48 (14%) were goats. The diseases were prevalent in all study zones, the highest sero-prevalence was observed in South Gondar (20.9%) and the lowest in North Gondar and West Gojjam zones (11.9% each). From the potential risk factors considered (species, sex, age, agro-ecology and location); only sex and age were significantly associated (p < 0.05) with the diseases in multivariable logistic regression. Female and young animals were at higher risk than their counterparts. From January 2010 to December 2014, a total of 366 outbreaks, 12,822 cases and 1480 deaths due to SP and 182 outbreaks, 10,066 cases and 997 deaths due to GP were recorded in Amhara National Regional State.ConclusionBoth the serological and the outbreak data revealed that sheep and goat pox is one of the most prevalent and widespread diseases of sheep and goats in the study area. Hence, annual mass vaccination program must be implemented for economic and viable control of sheep and goat pox diseases in the Amhara region in particular and at a national level in general.

Temporal and spatial distribution of lumpy skin disease outbreaks in Ethiopia in the period 2000 to 2015

BackgroundLumpy skin disease (LSD) is an infectious viral disease of cattle caused by a virus of the genus Capripoxvirus. LSD was reported for the first time in Ethiopia in 1981 and subsequently became endemic. This time series study was undertaken with the aims of identifying the spatial and temporal distribution of LSD outbreaks and to forecast the future pattern of LSD outbreaks in Ethiopia.ResultsA total of 3811 LSD outbreaks were reported in Ethiopia between 2000 and 2015. In this period, LSD was reported at least once in 82% of the districts (n = 683), 88% of the administrative zones (n = 77), and all of the regional states or city administrations (n = 9 and n = 2) in the country. The average incidence of LSD outbreaks at district level was 5.58 per 16 years (0.35 year−1). The incidence differed between areas, being the lowest in hot dry lowlands and highest in warm moist highland. The occurrence of LSD outbreaks was found to be seasonal. LSD outbreaks generally have a peak in October and a low in May. The trend of LSD outbreaks indicates a slight, but statistically significant increase over the study period. The monthly precipitation pattern is the reverse of LSD outbreak pattern and they are negatively but non-significantly correlated at lag 0 (r = −0.05, p = 0.49, Spearman rank correlation) but the correlation becomes positive and significant when the series are lagged by 1 to 6 months, being the highest at lag 3 (r = 0.55, p < 0.001). The forecast for the period 2016–2018 revealed that the highest number of LSD outbreaks will occur in October for all the 3 years and the lowest in April for the year 2016 and in May for 2017 and 2018.ConclusionLSD occurred in all major parts of the country. Outbreaks were high at the end of the long rainy season. Understanding temporal and spatial patterns of LSD and forecasting future occurrences are useful for indicating periods when particular attention should be paid to prevent and control the disease.

Poultry coccidial infection in local chicken from three selected districts of North Gondar Zone, Ethiopia

A cross-sectional study was conducted to determine the prevalence of poultry coccidial infection and to identify Eimeria species on local chicken in three selected districts of North Gondar, Northwest Ethiopia from October 2010 to March 2011. Two hundred sixty local chickens were purchased from three selected districts (Wogera, Dembya and Gondar town) which represent two agro-ecological zones. Identification of Eimeria species was based on the Oocyst morphology, predilection site, gross and histopathological changes in the intestine. The study indicated that 16.92% (44/260) of the chickens were infected with coccidia oocysts. Four Eimeria species were identified, namely, Ei meria maxima, Eimeria acervulina, Eimeria necatrix and Eimeria tenella with the prevalence estimate of 36.3%, 29.5%, 18.2%, and 15.9%, respectively. Age unlike sex was found to be significantly (P < 0.05) associated with coccidial infection. This study showed that coccidial infection (16.92%) could be important in the backyard system which was supposed to be low. Keywords: Coccidial infection, Eimeria species, Ethiopia, Local chicken, Prevalence