Detection and antibiogram profile of diarrheagenic Escherichia coli isolated from two abattoir settings in northwest Ethiopia: a one health perspective.

BACKGROUND: Diarrheagenic Escherichia coli (E. coli) is a zoonotic pathogen that contaminates abattoir workers, slaughter environments, slaughter equipment, and carcasses during abattoir processing. Infection with E. coli is associated with the consumption of contaminated food and water, and it is a potential threat to the health and welfare of both humans and animals. Hence, this study aimed to detect diarrheagenic E. coli and assess its antibiogram profile in two abattoir settings, in one health lens. METHODS: A cross-sectional study in one health approach was conducted from December 2020 to June 2021. A total of 384 samples from abattoir workers' hands, carcasses, knives, cattle feces, abattoir water and effluents were collected. Bacterial culture and biochemical tests were conducted to isolate E. coli, while conventional polymerase chain reaction was performed to identify virulence genes. The antibiogram of diarrheagenic E. coli was tested against nine antimicrobials using the Kirby Bauer disk diffusion method. RESULTS: A total of 115 (29.95%) E. coli were isolated from the 384 samples, and from these isolates, about 17 (14.8%) were confirmed to be diarrheagenic E. coli (DEC). Among the DEC pathotypes, nine (52.94%), five (29.4%), and three (17.65%) were Shiga toxin-producing, enterohemorrhagic, and enterotoxigenic E. coli, respectively. While 14 (82.35%) DEC isolates harbored the stx2 gene, five (29.41%) the eae gene, five (29.41%) the hlyA gene and three (17.65%) harbored the st gene. All the DEC isolates were resistant to erythromycin and vancomycin; whereas, they were susceptible to ampicillin, nalidixic acid and norfloxacin. Furthermore, 64.7% of DEC isolates showed resistance to both ceftazidime and kanamycin and 88.24% of the isolates showed multidrug resistance. CONCLUSION: This study detected DEC isolates having different virulence genes, which showed single and multiple antimicrobial resistance. Given the existing poor hygienic and sanitary practices along the abattoir-to-table food chain, coupled with the habit of raw meat consumption, this result indicates a potential public and animal health risk from the pathogen and antimicrobial resistance.

Seroprevalence and associated risk factors of equine herpesvirus type-1/-4 in selected districts of Northwest Amhara, Ethiopia.

This study aimed to estimate the prevalence, determine the distribution, and identify the epidemiological risk factors of EHV-1/-4 infections in selected districts of Northwest Amhara Region. 460 serum samples were collected from equines using multistage cluster sampling technique, and a competitive Enzyme-linked immunosorbent assay (cELISA) was performed. Various risk factors for the occurrence of EHV-1/-4 were considered. Statistical analysis was performed using R version 4.3.1. 65.9% (303) equids were tested positive for antibodies against EHV-1/-4. Based on district, the highest prevalence was recorded in Wogera (86.1%), while the lowest was in Debark (47.4%). There was a significant difference (p <0.05; 95% CI: 1.1067993-3.682843) in the prevalence of EHV-1/-4 among species and donkeys are 2.019 times more likely to get an EHV infection than horses. The prevalence of EHV-1/-4 was highest in equids with the age of 3-8 years and lowest in < 3 years, and the difference was statistically significant (p <0.05; 95% CI: 1.9812042-6.771820). Statistically significant variation (p <0.05; 95% CI: 1.1173822-2.684013) was also observed between sex of equids in which females had 1.73 times higher chance to get EHV infection than males. Higher prevalence was found in lactating equids (81.6%), followed by pregnant equids (74.6%), and dry equids (66.4%). Generally, this study indicated a high and wide distribution of EHV-1/-4 infection in the study area, which needs due attention. Devising strategies to prevent and minimize the spread and occurrence of the infection is crucial.

Risk factors associated with contagious caprine pleuropneumonia in goats of Amhara region, Ethiopia.

Contagious caprine pleuropneumonia (CCPP) is a serious contagious disease of goats, sheep and wild ruminants caused by Mycoplasma capricolum subspecies capripneumoniae. The disease is known for its high mortality, morbidity and economic losses. A cross-sectional study using multistage cluster sampling technique was conducted in Amhara region from January 2019 to July 2019 to estimate seroprevalence and identify risk factors of CCPP occurrence in the region. A total of 2080 goats from 61 villages and 12 districts of the region were tested for CCPP serostatus using Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA). A multilevel mixed-effect logistic regression model was used to identify risk factors of CCPP seropositivity at animal and flock-level. The serum sample results revealed an overall animal level seroprevalence of 5.1% (95% CI: 3.8-6.6) and flock-level prevalence of 26.0% (95% CI: 19.7-33.4). At individual animal level, presence of other health problems (OR = 45.9 (95% CI: 25.3-83.4)), age (adult age (OR = 6.2 (95% CI:3.4-11.4)) and old age (OR = 13.1 (95% CI: 6.2-27.8))), and breed type (Afar (OR= 32.3 (95% CI: 2.9-366.1)), Central highland (OR=13.7 (95% CI: 1.3-140.6)), and western highland (OR=16.2 (95% CI: 1.4-185.7))) were identified as risk factors for CCPP seropositivity. In contrast, contact with other flocks (OR = 59.9 (95% CI: 6.1-585.6)), presence of trade route (OR = 3.1 (95% CI: 1.0-9.1)) and presence of sheep (OR = 2.6 (95% CI: 1.2-5.7)) were flock-level risk factors for CCPP seropositivity. Generally, CCPP appears to be common among goats of Amhara region. Goat flocks dominated with older age animals; breeds of Afar, central highland, and western highland; raise with sheep; have contact with other flocks; and kept along trade routes are more at risk for CCPP. Hence, awareness creation to the producers, movement control, and regular prophylactic vaccination should be considered to control CCPP in Amhara region.

Ovine gastrointestinal parasite burden and the impact of strategic anthelmintic treatment in community-based breeding sites in Ethiopia.

Introduction: In Ethiopia, small ruminants contribute significantly to livelihoods and food security but productivity is low with high disease burden and essential endoparasite control not widely practiced. The current study assessed worm burden and its control in three districts in Ethiopia. Methods: All sheep older than 3 months in nine villages were treated en-masse with albendazole and triclabendazole twice a year from 2018 to 2021. Treatments were administered under field conditions by animal health workers. Pre- and post-treatment data were assessed looking at fecal egg presence/absence and fecal egg per gram (EPG) count. Results: A total of 1,928 and 735 sheep were examined before and after deworming, respectively. Before treatment worms were detected in 54.4% (95% CI: 52.2-56.6) of sheep. Strongylid (30.4%) and Fasciola (18.2%) were the most frequently identified parasites. Animals living in wet mid-highland environments were more than 23 times more likely to have strongylid eggs in their feces and 5 times more likely to have eggs from any gastrointestinal tract (GIT) parasites detected, as compared to animals living in moist highland agro-ecology. Over the course of the 2018-2021 community intervention there was total elimination of animals with a high worm burden (EPG > 1,500), and elimination of a third of those with moderate infections. Mild infections remained, largely accounted for by strongylid, which remains at low levels in healthy sheep. However, there were signs of emerging drug resistance. Conclusion: Generally, sheep in smallholder systems in Ethiopia experience a needlessly large economic burden from GIT worms. Routine therapy reduces this burden but smart strategies are needed to limit the onset of drug resistance.

Knowledge, attitude and practice related to rabies among residents of Amhara region, Ethiopia.

Background: Rabies is an important viral zoonotic disease with high fatality rate and economic losses. The impact of rabies is considerably high in Asia and Africa. The study was designed to assess the community's rabies knowledge, attitude and practice (KAP) and their determinants in Amhara region, Ethiopia. Methods: The study was done based on a questionnaire survey of 899 participants in towns and rural districts of Amhara region. Multistage cluster sampling procedure was used to select participants. Quantitative score was generated for KAP and the scores were dichotomized as adequate and inadequate knowledge, desirable and undesirable attitude, and good and poor practice. Descriptive statics and mixed effect logistic regression considering kebele and villages as a random effect was used to see the association of predictor variables towards adequate knowledge, desirable attitude and good practice. Results: About 61%, 72% and 45% of the respondents have adequate knowledge, desirable attitude and good practice scores, respectively. Almost all (99%) of the respondents rightly claimed that rabies is transmitted through bite of dogs. Majority of the participants (76.8%) strongly agree that rabies is an important zoonotic disease that can threaten the lives of humans and animals. Only 8% of the respondents had a practice of washing and rinsing dog bite wounds for the prevention of rabies. Female participants were less likely to have adequate knowledge than males (OR = 0.58, 95% CI = 0.35-0.96). Respondents in urban areas were more likely to have desirable attitude than rural residents (OR = 12.4, CI = 1.38-11.67). Conclusion: The study showed that participants have good knowledge and attitude towards rabies but poor rabies prevention and control practices. The community public health education should focus on translation of these good knowledge and favorable attitude into practices that effectively reduces rabies burden.

Epidemiology of Newcastle disease in chickens of Ethiopia: a systematic review and meta-analysis.

The objective of this systematic review was to estimate the overall pooled prevalence of Newcastle disease in chickens in Ethiopia and identify the sources of heterogeneity among and within studies. The seroprevalence of Newcastle disease was estimated using a single-group meta-analysis. Attempts were also made to identify study-level variables that could explain the heterogeneity in the apparent seroprevalence of the Newcastle disease. The findings were based on 16 published articles and 33 district-level reports and were limited to studies performed during 2005-2017. Due to the presence of heterogeneity, pooled analysis from different districts was conducted using random-effects meta-analysis. The single-group summary of Newcastle disease seroprevalence in chickens was estimated to be 21.47% (19.54-23.4%) with a 95% confidence interval. Our results indicated high inter-study variability (Cochran's Q statistic = 196.2, true variance (τ2) = 0.36, inverse variance index (I2) = 90.0%, p < 0.001). Of all variables analysed, diagnostic techniques and regions were the most significant predictors (p ˂ 0.05) of heterogeneity. According to the diagnostic technique-based meta-analysis of random pooled prevalence, the haemagglutination inhibition test had the highest prevalence, followed by the enzyme-linked immunosorbent assay. In conclusion, the high-pooled prevalence estimates of the disease, combined with the scarcity of published data for the entire country of Ethiopia, indicate a significant data gap on the distribution of Newcastle disease in the country. While the high pooled prevalence tells the need for intervention to control the disease, there is also a need to assess the disease prevalence in all other parts of the country.

Serotyping and Seroprevalence of Mannheimia haemolytica, Pasteurella multocida, and Bibersteinia trehalosi and Assessment of Determinants of Ovine Pasteurellosis in West Amhara Sub-region, Ethiopia.

A cross-sectional study was undertaken in four (4) districts of the West Amhara sub-region of Ethiopia with the aim of assessing the diversity and distribution of serotypes of Pasteurella species, their seroprevalence, and associated risk factors, and knowledge, attitude, and practice of farmers toward ovine pasteurellosis. A total of 600 sheep sera were collected using multistage cluster sampling. Each sample was examined for the presence of six (6) serotype-specific antibodies using an indirect haemagglutination test. We are reporting a higher seroprevalence of 90.17% (541/600) in which all seropositive animals were shown to have been co-infected with multiple serotypes. Individual serotype prevalence showed that serotype A7 has the highest prevalence of 77.83% followed by A2 (74.33%), T15 (64%), T4 (62%), PA (60%), and A1 (39.17%). In this study, being female [odds ratio (OR): 2.45, 95% CI (1.09-5.52), p = 0.031] and living in high altitude areas [OR: 20.29, 95% CI (2.54-161.95), p = 0.004] were found to be significantly associated with sero-positivity. A questionnaire survey (n = 384) employed in a face-to-face interview was used to assess the knowledge, attitude, and practice of farmers related to ovine pasteurellosis. Accordingly, the majority (72.4%) of respondents had an inadequate knowledge level of the disease. The proportion of farmers with a favorable attitude and good practices toward the disease was 50.26 and 77.6%, respectively. This study is highly indicative that ovine pasteurellosis is a ubiquitous disease in the study area challenging the sheep production sector. The existence of diverse serotypes reported to lack cross-protective immunity is likely to explain why the current vaccination practice with the mono-serotype Pasteurella multocida biotype A vaccine is not providing adequate protection against outbreaks of the disease. Prioritization of one or more serotypes for inclusion in a multivalent vaccine should be dictated by the abundance and distribution of a particular serotype, its clinical importance, and its resultant economic impact. Furthermore, training farmers on key aspects of the disease is vital in the implementation of effective disease management strategies through a participatory approach. Data from the remaining regions of the country could help realize the development of an effective vaccine that works best at the national level.

Risk factors associated with lumpy skin disease in cattle in West Kazakhstan.

Lumpy skin disease is an important emerging disease posing a threat to the livestock industry worldwide. Moreover, factors involved in disease transmission in the field and at farm level remain unidentified. This research was based on a cross-sectional study using a questionnaire administered through face-to-face interviews with affected farmers. From January 2021 to July 2021, 543 households were visited in four provinces of the West Kazakhstan region to assess the prevalence of LSD and its associated risk factors. Animal and farm level risk factors were examined using univariable and multivariable mixed effect logistic regression. At animal level, the factors associated with LSD outbreaks include herd size Medium OR = 0.68, (95% CI: 0.54-0.84); large OR = 0.63, (95% CI: 0.49-0.81), purchasing animals OR = 11.67, (95% CI: 8.87-15.35), and selling animals during LSD outbreak OR = 1.24, (95% CI: 1.06-1.45). The overall animal level and herd level LSD prevalence were 10.2% (95% CI: 9.6 -0.10.9) and 49.2% (95% CI: 45.0 - 53.4) respectively. Our study demonstrates the dissemination of LSDV from primary outbreaks to new areas and risk factors associated with LSD in Kazakhstan. This finding will enhance knowledge on disease epidemiology and help develop coordinated actions in prevention and control of the possible LSD outbreaks.

Reduced Milk Production, Economic Losses, and Risk Factors Associated to Subclinical Hypocalcemia in Holstein Friesian × Zebu Crossbreed Cows in North-West Ethiopia.

Hypocalcemia is a metabolic disorder that occurs when calcium leaves the blood to support milk production or for the growth of the fetus faster than calcium can be put back into the blood. Subclinical hypocalcemia (SCH) refers to clinically normal cows but with concentrations of calcium lower than measured in normal cows. A study was conducted to estimate economic losses and to identify risk factors associated with SCH in Holstein Friesian × Zebu crossbreed Cows in North-West Ethiopia. A total of 221 lactating dairy cows obtained from 81 dairy farms were selected and serum samples were collected and analyzed to estimate the level of calcium in the serum using an automated electrolyte analyzer (Roch, UVL Japan, 2014). Forty-seven cows obtained from 12 farms were grouped into two: cows with SCH and cows without SCH and milk yield was measured for eight consecutive days to estimate milk production loss associated with SCH. Prevalence was estimated and univariable and multivariable logistic regression analyses were used to identify determinants of SCH. The prevalence of SCH was 20.3% (51/221, 90% CI = 18.6%-28.1%). Grazing on pasture, membership to dairy cooperative, feeding above the cows' requirement (based on farmers' opinion), and previous experience of metritis reduced the odds of SCH (P < 0.05). The average economic losses associated with reduced milk production due to SCH were 11.25 Ethiopian Birr (ETB) (1 ETB = 0.023 US Dollar) and 3,026.25 ETB (69.6 US Dollar) per cow per lactation, respectively. The main findings of the study have shown that SCH was a problem in crossbreed dairy cows in Northwestern Ethiopia and identified few risk factors that could be targeted to mitigate the problem. Actually, in this study, the economic cost of SCH was significant and needs attention in the dairy extension and dairy health training programs.

Risk factors for Brucellosis and knowledge-attitude practice among pastoralists in Afar and Somali regions of Ethiopia.

BACKGROUND: Brucellosis is a neglected bacterial zoonotic disease with substantial economic impact on households. Pastoral communities are a potential risk group due to their way of life being closely interlinked with their large livestock herds. METHODOLOGY: A semi-structured questionnaire survey was conducted in households in the pastoral Afar and Somali (SRS) regions. All households had people and animals serologically tested for brucellosis. Questions were related to husbandry, consumption habits, and knowledge-attitude-practice towards the disease and zoonoses. Descriptive statistics and logistic analysis were performed to assess potential risk factors for having households with positive humans and/or animals. RESULT: 647 households were included in the survey. Herd brucellosis prevalence was 40.3 % (15.9-86.3 % in Afar; 4-72.2 % in SRS). Over half (56.3 %) of the households in Afar and 41.8 % in SRS had at least one human reactor. Nearly a quarter of the households (22.8 %), recalled abortions in goats in the last 12 months, whereas 52.5 % and 50.3 % recalled stillborn in all species and membrane retentions respectively. All respondents drank raw milk and discarded animal afterbirths in the direct surroundings with minimal protection. Risk factors for animal reactors were goat herd size, and goat abortion. There was no identified risk factor for having human reactors in households. None of the households knew about brucellosis. CONCLUSION: Although being endemic in Afar and SRS, Brucellosis is not known by the pastoralists. Brucellosis control programs will have to be tailored to the pastoral context, accounting for their mobility, large, multi-species herds and habits.

Health and economic burden of foodborne zoonotic diseases in Amhara region, Ethiopia.

Diseases from food of animal origin are common health problems in Ethiopia. A cross-sectional study was carried out to estimate health and economic burden, and to identify demographic factors associated with community awareness of foodborne zoonotic diseases in Amhara region, Ethiopia. Data was collected from 435 households in three towns: Gondar, Lalibela and Debark. A retrospective data was also collected from health records in each town. The health burden due to zoonotic diseases was estimated at 0.2, 0.1 and 1.3 DALYs per household per year and at 73.2, 146.6 and 1,689.5 DALYs out of 100,000 populations per year in Gondar, Lalibela and Debark, respectively. The overall health burden due to foodborne zoonotic diseases (aggregated over the 435 households in the three towns) was estimated to be 89.9 DALYs per 100,000 populations per year. The economic impact of foodborne zoonotic diseases in the three towns of Amhara regional state was 278.98 Ethiopian Birr (ETB) (1ETB = 0.025 US Dollar) per household per year and 121,355.68 ETB per year. Costs of preventive measures followed by costs of patients' time made the highest contribution while costs of diagnosis made the lowest contribution to the total economic burden of foodborne zoonotic diseases. From a total of 435 respondents, 305 (70.1%) had known the presence of zoonotic diseases. Level of education, number of families in the house and income were highly associated with awareness of zoonosis. Although majority of respondents had known zoonotic diseases exists (70.1%) and disease can be acquired from animal source food (63.2%), the health and economic burden associated to foodborne zoonotic diseases are still high. Therefore, changing mindset and practical training aiming in controlling foodborne zoonotic diseases may be suggested to the community in the health improvement extension service.

Integrated human-animal sero-surveillance of Brucellosis in the pastoral Afar and Somali regions of Ethiopia.

BACKGROUND: Brucellosis is widespread in Ethiopia with variable reported prevalence depending on the geographical area, husbandry practices and animal species. However, there is limited information on the disease prevalence amongst pastoral communities, whose life is intricately linked with their livestock. METHODOLOGY: We conducted an integrated human-animal brucellosis sero-surveillance study in two adjacent pastoral regions, Afar and Somali region (SRS). This cross-sectional study included 13 woredas (districts) and 650 households. Blood samples were collected from people and livestock species (cattle, camel, goats and sheep). Sera were analyzed with C-ELISA for camels and shoats (sheep and goats), with I-ELISA for cattle and IgG ELISA for humans. Descriptive and inferential statistics analyses were performed. RESULTS: A total of 5469 sera were tested by ELISA. Prevalence of livestock was 9.0% in Afar and 8.6% in SRS (ranging from 0.6 to 20.2% at woreda level). In humans, prevalence was 48.3% in Afar and 34.9% in SRS (ranging from 0.0 to 74.5% at woreda level). 68.4% of all households in Afar and 57.5% of households in SRS had at least one animal reactor. Overall, 4.1% of animals had a history of abortion. The proportion of animals with abortion history was higher in seropositive animals than in seronegative animals. Risk factor analysis showed that female animals were significantly at higher risk of being reactors (p = 0.013). Among the species, cattle had the least risk of being reactors (p = 0.014). In humans, there was a clear regional association of disease prevalence (p = 0.002). The older the people, the highest the odds of being seropositive. CONCLUSION: Brucellosis is widespread in humans and animals in pastoral communities of Afar and SRS with the existence of geographical hotspots. No clear association was seen between human and particular livestock species prevalence, hence there was no indication as whether B. abortus or B. melitensis are circulating in these areas, which warrants further molecular research prior to embarking on a national control programs. Such programs will need to be tailored to the pastoral context.

Seroprevalence and Risk Factors of Contagious Bovine Pleuropneumonia in Selected Districts of North Gondar Zone, Ethiopia.

Contagious bovine pleuropneumonia (CBPP) is an infectious and highly contagious respiratory disease of cattle and water buffalo, which is caused by the Mycoplasma mycoides subspecies mycoides small colony. It induces significant economic losses and leads to a serious food security problem, negatively influencing peoples' livelihoods in affected countries. The disease has been reported in different parts of Ethiopia with prevalence ranging from 1.78 to 96%. However, there is not enough epidemiological information about CBPP in the northwestern part of the country, particularly in North Gondar Administrative Zone. This cross-sectional study, therefore, was conducted in four selected districts (Metema, Alefa, Quara, and Dembia) of North Gondar Administrative Zone to detect the incursion and estimate the seroprevalence of CBPP and to identify the potential predisposing factors associated with the spread and occurrence of CBPP in the area. A total of 751 serum samples were collected from 41 herds (villages) having no history of CBPP vaccination. Information like age, sex, breed, herd size, and management were collected during blood sample collection. Data related to agro-climatic zone, trade trekking route from or through CBPP endemic/epidemic zone, transhumance grazing route, vehicle route, and bordering with CBPP epidemic/endemic zone were obtained from district agricultural offices. The serum was screened for CBPP using competitive enzyme-linked immunosorbent assay (c-ELISA) test. The animal level and herd level apparent seroprevalences were 12.92% (95% CI: 10.70-15.52) and 65.85% (95% CI: 49.57-79.10), respectively. The true animal level and herd level prevalences were estimated at 20.13% (95% CI: 16.64-24.21) and 65.22% (95% CI: 48.64-78.72%), respectively. At the animal level, trekking route from or through CBPP endemic/epidemic zone to the study area [OR = 4.77 (95% CI: 1.92-11.84) compared to without trekking route] was identified as the most important risk factor for CBPP spread and seropositivity. In general, epidemiological evidence of the present study indicates that CBPP is a prevalent disease, and animal trekking is an important risk factor for spread of the disease in the study area. This needs due attention from the government and other concerned bodies for its prevention and control to mitigate its economic impact.

Farmers' willingness to pay for foot and mouth disease vaccine in different cattle production systems in Amhara region of Ethiopia.

Although foot and mouth disease (FMD) is endemic in Ethiopia, use of vaccines to control the disease has been practiced sparingly. This is due to perceived high cost of good quality FMD vaccine, and consequently limited availability of the vaccine in the market. This study was conducted to assess farmers' willingness to pay (WTP) for a quality FMD vaccine and identify factors that could potentially influence their WTP in Amhara region of Ethiopia. A total of 398 farmers from four districts that represent the mixed crop-livestock and market oriented production systems were enrolled for the study. The WTP was estimated using contingent valuation method with a double-bound dichotomous choice bid design. Interval regression analysis was used to estimate mean WTP and identify factors that influence it. The results showed that the mean WTP of all farmers was Ethiopian Birr (ETB) 58.23 (95% CI: 56.20-60.26)/annual dose. It was ETB 75.23 (95% CI: 72. 97-74.49) for market oriented farmers and ETB 42.6 (95%CI: 41.24-43.96) for mixed crop livestock farmers. Willingness to pay for the vaccine was significantly higher for farmers in market oriented system than in mixed crop livestock system. It was also significantly higher for farmers whose main livelihood is livestock than those whose main livelihood is other than livestock, and for farmers who keep exotic breed cattle and their crosses than those who keep only local cattle breeds. Willingness to pay significantly increased with increase in FMD impact perception and vaccine knowledge scores of farmers. The high mean WTP estimates showed that farmers are enthusiastic about using the FMD vaccine. Market-oriented farmers with higher willingness to pay may be more likely to pay full cost if official FMD vaccination is planned in the country than mixed crop livestock farmers. Animal health extension about livestock diseases impact and vaccines has a potential to increase farmers' uptake of vaccines for disease control.

A randomized controlled field trial assessing foot and mouth disease vaccine effectiveness in Gondar Zuria district, Northwest Ethiopia.

Foot and mouth disease (FMD) is a highly transmissible viral disease of cloven-hoofed animals, which is endemic in many developing countries. Vaccination is the main tool for FMD control in resource limited endemic countries like Ethiopia. Vaccine quality, which is often questionable in developing countries, is a critical element for effective disease control. The present study was aimed at evaluating the field effectiveness of a trivalent FMD vaccine (containing serotypes O, A and SAT 2), produced and widely used in Ethiopia, in terms of preventing clinical infection and severe disease. A randomized controlled field trial design was employed in the study in which the attack rate of clinical FMD infection in vaccinated cattle was compared with the attack rate in unvaccinated controls in cattle population of 16 villages in Gondar Zuria district, Northwest Ethiopia. The vaccine was administered as a single dose course in the face of an impending FMD outbreak and the trial groups were monitored for clinical infection until the end of the outbreak. The attack rate of clinical FMD 20 days post vaccination in the vaccinated cattle (34 %) was significantly lower than the attack rate in the unvaccinated controls (49 %) (p < 0.001). However, the effectiveness of the vaccine was only 31 % (95 %CI: 20-40 %). This vaccine effectiveness increased to 52 % ((95 %CI: 33-66 %) 42 days post vaccination. The proportion of severely affected cattle in the vaccinated group (5.7 %) was significantly lower than in the unvaccinated group (9.4 %) (p < 0.001), resulting in 39 % (95 %CI: 18-55 %) vaccine effectiveness against severe disease. Generally, the observed level of vaccine effectiveness was lower than the internationally recommended 75 % plus expected percentage of protection for a standard potency 3PD50/dose FMD vaccine. Moreover, the level of effectiveness was insufficient to provide herd immunity to control the disease at the population level. Nevertheless, given the significant difference in the incidence of clinical disease and severity between vaccinated and unvaccinated cattle, it might still be worth using the current vaccine to reduce production losses associated with the disease provided it is cost effective and affordable for the farmers. Factors that cause low effectiveness of the vaccine need to be identified and addressed for effective control of the disease at population level.

Spatial and temporal distribution of foot and mouth disease outbreaks in Amhara region of Ethiopia in the period 1999 to 2016.

BACKGROUND: Foot and mouth disease (FMD) is an economically important trans-boundary viral disease of cloven-hoofed animals. It is caused by FMD virus, which belongs to the genus Aphthovirus and family Picornaviridae. FMD is a well-established endemic disease in Ethiopia since it was first detected in 1957. This retrospective study was carried out to identify the spatial and temporal distribution of FMD outbreaks in Amhara region of Ethiopia using 18 years (January 1999-December 2016) reported outbreak data. RESULTS: A total of 636 FMD outbreaks were reported in Amhara region of Ethiopia between 1999 and 2016 with an average and median of 35 and 13 outbreaks per year respectively. In this period, FMD was reported at least once in 58.5% of the districts (n = 79) and in all administrative zones of the region (n = 10). The average district level incidence of FMD outbreaks was 4.68 per 18 years (0.26 per district year). It recurs in a district as epidemic, on average in 5.86 years period. The incidence differed between administrative zones, being the lowest in East Gojjam and highest in North Shewa. The occurrence of FMD outbreaks was found to be seasonal with peak outbreaks in March and a low in August. The long-term trend of FMD outbreaks indicates a slight, but statistically significant (p < 0.001) decrease over the study period. CONCLUSION: FMD occurred in all zones of the region and showed statistically significant decrease in the long-term trend. Numbers of outbreaks were relatively higher during dry season. The spatial and temporal distribution identified in this study should be considered in controlling the disease. As unregulated and frequent animal movements are the likely causes of high outbreak occurrence during the dry season, animal movement regulations should be considered for the long-term control of FMD.

Foot and mouth disease outbreak investigation and estimation of its economic impact in selected districts in northwest Ethiopia.

Foot and mouth disease (FMD), a highly contagious and economically important disease of cloven-hoofed animals, is endemic in Ethiopia. Foot and mouth disease outbreak investigation and follow-up studies were undertaken to identify the causative serotype, determine the morbidity and mortality, and estimate the economic impact of the outbreaks in selected districts of Northwest Ethiopia. The serotype of FMD virus involved in the outbreaks was identified by antigen detection ELISA from clinical samples. Morbidity, mortality and economic impact of the outbreaks were assessed based on data collected from 738 smallholder farmers in a mixed crop-livestock (MCL) production system and from five dairy farms in the commercial dairy production system. The outbreaks were confirmed to be due to FMD virus serotype O. The animal level morbidity in clinically affected cattle herds was 68.1% for MCL production system and 54.5% for commercial dairy farms. The mortality in cattle in the MCL system was 0.4% and no mortality was recorded in the commercial dairy farms. The animal level morbidity in sheep and goats in the infected flocks was 35.7% but no mortality was seen in these species. The herd/flock level morbidity of FMD in outbreak affected kebeles of MCL system was 57.2% for cattle and 8% for sheep and goats. The economic losses due to milk loss, draught power loss, mortality and treatment cost were on average USD 34 (interquartile range: 9.4-44.4) per affected herd in the MCL system and this was statistically significantly lower than the USD 459.1 (interquartile range: 400.0-486.2) per affected farm in the commercial dairy farms (p < .05). These economic losses have significant impact in the livelihood and income of affected farmers in both production systems. Future work should focus on the implementation of control measures that mitigate the economic impact of the disease.

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.

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

BACKGROUND: Orf 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. METHODS: a 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). RESULTS: Out 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). CONCLUSION: The result of the present finding showed high incidence of Orf virus in the region as confirmed through PCR.

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.