Epidemiology and economic impact of lumpy skin disease of cattle in Mymensingh and Gaibandha districts of Bangladesh.

Lumpy skin disease (LSD) is an emerging viral disease of cattle that negatively impacts livestock by reducing animals' production and increasing management costs. Like other countries, Bangladesh has also faced the ominous effects of LSD. Because of this pressing concern, the present study was undertaken to determine the attack rate and risk factors along with economic losses of the recent LSD outbreaks from October 2019 to June 2020 in Bangladesh's Mymensingh and Gaibandha districts. A total of 1187 cattle from 150 randomly selected cattle farms were surveyed. The diagnosis was made both clinically and molecularly. The overall attack rate, mortality and case fatality were 34%, 1.10% and 3.23%, respectively, but in calves up to 1 month of age, the attack rate, mortality and case-fatality were 41.6%, 12.5% and 30%, respectively. In risk factor analysis using multiple logistic regression, the following factors were significantly (p < .05) associated with LSD occurrence: no administration of goat pox vaccine, frequency of goat pox vaccination - single dose, introduction of new cattle, land type (low land and medium-high land), use of common syringe and needle, and use of common utensils. The average economic loss per case was 9384.41 BDT (110.40 US $). The higher economic loss per case was accounted in Mymensingh district (10248.91 BDT ≈ 120.58 US $) than Gaibandha district (8211.52 BDT ≈ 96.61 US $). The loss was higher in crossbred cattle (9709.58 BDT ≈ 114.23 US $) compared to indigenous cattle (7595.94 BDT ≈ 89.36 US $). The total estimated annual loss due to LSD in Mymensingh and Gaibandha districts was 7763.25 million BDT (91.33 million US $). In Gaibandha district, the estimated annual loss was 2666.20 million BDT (31.37 million US $) while in Mymensingh district it was 5097.05 million BDT (59.97 million US $). Findings of the study could provide useful epidemiological data with losses incurred due to LSD to the livestock owners, field veterinarians and government-level livestock regulators, which will help to formulate prevention and control strategies and minimize the negative impact of LSD's probable return or spread.

Assessment of heterologous lumpy skin disease vaccine-induced immunity in pregnant cattle vaccinated at different times of gestation period and their influence on maternally derived antibodies.

The present study aimed to evaluate the cell-mediated and the humoral immune response to Romanian sheep pox vaccine in pregnant cows (n = 12) vaccinated at different times of gestation period and the duration of maternal immunity in calves born to these cows. Evaluation of cellular immunity revealed an increase in lymphocytic proliferation that peaked at 10th day post vaccination (dpv) then gradually decreased. Capripoxvirus-specific antibodies were detected by SNT and ELISA in sera collected from vaccinated dams and also in calves born to these cows. In cows, the antibody titers persisted above the protective level till the seventh month post-vaccination. Passively transferred antibody titers in newly born calves started from the first week after parturition and persisted in a protective level until 2, 3 or 4 months of ages in calves born to cows vaccinated at ≤4th, 4.5:6th, or >6:8th months of pregnancy respectively. Results proved that the average neutralizing antibody titers did not differ between pregnant cows vaccinated at different times of gestation period however, the longevity of maternally derived antibodies depends on the pregnancy stage at which the dam receive vaccine.

Farmers' preference and willingness to pay for a multivalent lumpy skin disease and Rift Valley fever novel vaccine: A discrete choice experiment in the Free State province, South Africa.

Rift Valley fever and lumpy skin disease are infectious ruminant diseases that are endemic in most African countries. The most cost-effective method of prevention and control is through annual vaccination. However, unlike lumpy skin disease, annual vaccination against Rift Valley fever is not practiced by many farmers due to its sporadic occurrences and shortcoming of the existing vaccines. This necessitates development of novel vaccines that would provide dual protection against a Rift Valley fever and a more prevalent disease. In this study, a discrete choice experiment was undertaken to guide vaccine development by examining the value smallholder livestock farmers place on different vaccine attributes and related attribute levels. The attributes considered are target-species, thermotolerance, nature of the vaccine, efficacy and price. The study was carried out with 164 smallholder livestock farmers in the Free State province. Results indicate that thermostaility is not a major deciding attribute to smallholder farmer's choice of vaccine. Farmers prefer multivalent vaccines, which are highly efficacious with about 90-100 % efficacy levels. Farmers were found to be heterogeneous in preference. The heterogeneity is explained by socio-economic factors such as type of livestock owned, income level, gender and perceived disease risk. Farmers were also willing to pay for preferred attribute levels. However, for less favourable levels such as multispecies, female farmers were willing to accept a lower compensation than males. These findings present a favourable potential for development of a novel multivalent vaccine and also provide vaccine research and development scientists with evidence based knowledge for development of vaccines that cater for the needs of smallholder farmers.

Economic cost of lumpy skin disease outbreaks in three Balkan countries: Albania, Bulgaria and the Former Yugoslav Republic of Macedonia (2016-2017).

Lumpy skin disease (LSD) is an emerging viral disease that was detected for the first time in the Balkan Peninsula in Greece in 2015. In April 2016, there was a reoccurrence in Greece and the spread of the disease for the first time into Bulgaria, the Former Yugoslav Republic of Macedonia, Serbia, Kosovo, Albania and Montenegro. The veterinary services of the countries responded with different strategies to control the disease, mostly based on mass vaccination campaigns and diverse stamping out approaches. During 2017, the epidemic was mostly controlled except for outbreaks reported in Albania, Greece and the Former Yugoslav Republic of Macedonia. The study aims to quantify the cost of disease and control measures in three selected Balkan countries, that is, Albania, Bulgaria and the Former Yugoslav Republic of Macedonia, which were differently affected by the disease, had different animal production structures and implemented different control strategies. The total cost for the three countries was 20.9 million Euro (EUR 20.9 m), mostly incurred in 2016 (EUR 16.6 m), when the disease was spreading throughout the Balkan region. In 2017 (data until October), the cost was EUR 4.0 m, mainly due to vaccination costs. Bulgaria was the country with the highest total cost at EUR 8.6 m, followed by the Former Yugoslav Republic of Macedonia (EUR 6.7 m) and Albania (EUR 5.3 m). According to our data, the average cost per affected herd in 2016 was EUR 869, EUR 6,994 and EUR 3,071 in Albania, Bulgaria and the Former Yugoslav Republic of Macedonia, respectively. The cost per animal in the affected herds was EUR 539, 147 and 258, respectively. The results from this study are useful to understand the cost of LSD outbreaks in the region, which might contribute to improve the surveillance and control of the disease.

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.

Lumpy skin disease: preliminary vaccine efficacy assessment and overview on outbreak impact in dairy cattle at Debre Zeit, central Ethiopia.

This study was conducted in and around Debre Zeit town to assess the field efficacy of LSD vaccine in use and overview associated disease impact. The study comprised cross-sectional and retrospective study design which employed active disease follow-up, semi-structured questionnaire survey and molecular techniques. The finding revealed that the Kenyan sheep pox vaccine strain used for the control of LSD did not confer expected protection. From the total of 476 animals observed, 22.9% and 2.31% cattle were found sick and dead due to LSD, respectively. Breed specific morbidity rate was 22.5% in Holstein Friesian-zebu cross and 25.9% in local zebu breed. The disease was observed to be more serious in young animals and also in females. A trend of seasonality was also observed in its occurrence. The study finding urges the need for investigation of vaccine failure including vaccine matching and alternative vaccine development.

Epidemiological aspects and financial impact of lumpy skin disease in Ethiopia.

The financial cost of clinical Lumpy Skin Disease (LSD) and the financial benefit of its control through vaccination were studied based on questionnaire survey in Oromia region of Ethiopia from the perspective of livestock farmers. Production loss impacts for local zebu cattle were compared with those of Holstein Friesian (HF)/crossbred cattle in the study area. Annual cumulative incidence of LSD infection in HF/crossbred and local zebu cattle were 33.93% (95% CI: 30.92-36.94) and 13.41% (95% CI: 12.6-14.25) respectively and significantly different (p<0.05). Annual mortality was also significantly higher in HF/crossbred 7.43% (95% CI: 5.76-9.10) than in local zebu cattle 1.25% (95% CI: 0.98-1.52). The annual financial cost was calculated as the sum of the average production losses due to morbidity and mortality arising from milk loss, beef loss, traction power loss, and treatment and vaccination costs at the herd level. The financial cost in infected herds was estimated to be USD 6.43 (5.12-8) per head for local zebu and USD 58 (42-73) per head for HF/crossbred cattle. A partial budget analysis was used to estimate the financial benefit of an annual vaccination program in both the local zebu and HF/crossbred cattle farming systems. The marginal rate of return (MRR) gained from this control intervention was estimated to be 34 (3400%) and the net benefit per head was USD 1 for local zebu and USD 19 for HF/crossbred cattle. Vaccination thus enabled financial costs due to LSD to be reduced by 17% per head in local zebu herds and 31% per head in HF/crossbred herds. These results could provide guidance to producers and the government in their endeavors to control the disease.