Sero-epidemiology of foot-and-mouth disease in some border states of Nigeria

A serological survey was conducted between 2009 and 2011 in six Border States and two other states that lie on the major cattle trek routes in Nigeria with the objective of determining the seroprevalence of foot and mouth disease (FMD) in cattle and demonstrate the evidence of antibodies in sheep, goats and pigs. Four hundred and forty-eight (448) sera were screened for FMD antibodies using the Enzyme-linked immunosorbent assay (ELISA) including samples collected during suspected field outbreaks. Statistics was conducted by using the modified Wald method and two-by-two contingency table. Higher seroprevalence was recorded in cattle samples from Yobe State (82%), followed by those from Plateau (80%), Ogun (77.77%), Taraba (73.50%), Adamawa (68%), Borno (67%), Sokoto (63%) cattle and Bauchi (27.84%), is only in sheep and goat. None of the pig sera obtained from Kaduna was positive. There is no difference in seropositivity between cattle sampled at the border and those from the trek routes. The result confirmed that FMD is still an important cattle disease in Nigeria since the diagnostic procedure employed in this analysis only detect positive serum in FMD infected animals and no history of vaccination was declared for any of the surveyed animals. Based on these results, it will be important to determine the recently circulating virus strains and factors responsible for the widespread seropositivity in order to design appropriate control strategies to limit the effect of FMD particularly on the Nigerian cattle.http://www.academicjournals.org/AJMRab201

Impact of foot-and-mouth-disease on goat behaviour after experimental infection with serotype SAT1 virus

Infectious diseases and parasitic infestations can cause a set of non-specific clinical signs, such as increased body temperature and resting, and a decrease in food intake. These physiological and behavioural changes have an adaptive function facilitating defences against the pathogen and to support immune functions. These so-called’ sickness behaviours’ can also be used as an early detection tool for disease. Foot-and-mouth disease (FMD) still causes great economic losses in endemic countries, especially to smallholder farmers. The aim of this study was to determine if behavioural changes in goats can be used as an early indicator of FMD virus (FMDV) infection. The efficacy of a Southern African Territories (SAT) FMD vaccine was studied on forty South African indigenous goats. Changes in daily activities (resting, feeding, walking), as well as social behaviours (social resting, social feeding, dominance behaviours) were recorded and then compared over time and between clinically affected and unaffected goats. Pedometers were used to estimate average daily steps and to compare between groups of study animals. Eleven goats developed clinical signs of FMD, as well as non-FMD related sicknesses during the course of the study. Overall walking and resting behaviours were not significantly affected by the presence of FMD related clinical signs (p > 0.05). However, during the time of FMDV infection, social resting increased significantly (p < 0.001). Although goats developed FMD lesions on lips and tongues, percentage of time feeding was not affected (p = 0.762), suggesting that the study goats did not perceive the oral lesions as an important disturbance. Similarly, the number of steps did not consistently decrease in the presence of FMD-associated foot lesions. When affected by non-FMD related sicknesses, animals did not have an overall reduction in the time spent feeding (p = 0.867). However, goats affected with non-FMD conditions reduced the amount of social feeding (p = 0.002), potentially avoiding energetically costly competition at the feeding points. Overall, goats affected with FMD did not show more sickness behaviour, suggesting that FMDV infection in goats might not lead to obvious and therefore, easily detectable behavioural changes. This might have implications for farmers and animal health personnel, as individual goats infected with FMDV might be undetected within a flock due to the absence of obvious sickness behaviours, and the virus can therefore be spread more easily between herds through animal movements.The National Research Foundation (NRF), South Africa and the Peace Parks Foundation.http://www.elsevier.com/locate/prevetmedhj2021Mammal Research InstituteProduction Animal Studie

Cost implications of African swine fever in smallholder farrow-to-finish units : economic benefits of disease prevention through biosecurity

African swine fever remains the greatest limitation to the development of the pig industry in Africa, and parts of Asia and Europe. It is especially important in West and Central African countries where the disease has become endemic. Biosecurity is the implementation of a set of measures that reduce the risk of infection through segregation, cleaning and disinfection. Using a 122-sow piggery unit, a financial model and costing were used to estimate the economic benefits of effective biosecurity against African swine fever. The outcomes suggest that pig production is a profitable venture that can generate a profit of approximately US$109 637.40 per annum and that an outbreak of African swine fever (ASF) has the potential to cause losses of up to US$910 836.70 in a single year. The implementation of biosecurity and its effective monitoring can prevent losses owing to ASF and is calculated to give a benefit-cost ratio of 29. A full implementation of biosecurity will result in a 9.70% reduction in total annual profit, but is justified in view of the substantial costs incurred in the event of an ASF outbreak. Biosecurity implementation is robust and capable of withstanding changes in input costs including moderate feed price increases, higher management costs and marginal reductions in total outputs. It is concluded that biosecurity is a key to successful pig production in an endemic situation.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1865-1682ab201

Improving foot-and-mouth disease control through the evaluation of goat movement patterns within the FMD protection zone of South Africa

Foot-and-mouth disease (FMD) is a transboundary animal disease that has a major impact on livestock production, regional and international trade and livelihoods of smallholder farmers in endemic settings. Many livestock diseases are transmitted through direct contact between animals, and thus between herds and flocks through animal movements. In this study, we described the pattern of goat movements among smallholder farmers within a communal farming area in South Africa. A cross-sectional survey using a semi-structured questionnaire was administered to 116 respondents, and separate 13 focus group discussions employing participatory mapping and semi-structured interviews were conducted among smallholder farmers. Overall, 22% (95% confidence interval [CI]: 16 – 31) of questionnaire respondents indicated moving new animals into their holdings during the previous 12 months while 56% (95% CI: 47 – 65) reported moving animals out of the holdings during the same timeframe. A total of 134 participants attended the focus group discussions with 68% (91/134) being male and 32% (43/134) female. Data from the study reported 37 nodes and 78 ties with an overall network density of 0.059 (SD 0.2) across the study area. Four locations within the (former) FMD-free zone of the country had connections with movement of goats from the study area. Furthermore, 60% (95% CI: 51 – 69) of farmers were ignorant of the need to obtain official veterinary movement permits for goats. These animal movements put the country at risk of future FMD outbreaks within the free zone. We recommend that the relevant authorities implement risk-based control measures to prevent the spread of infectious diseases.http://www.elsevier.com/locate/smallrumres2022-06-05hj2021Mammal Research InstituteProduction Animal Studie

Efficacy of a foot-and-mouth disease vaccine against a heterologous SAT1 virus challenge in goats

Please read abstract in the article.The National Research Foundation (NRF), South Africa and the Peace Parks Foundation.http://www.elsevier.com/locate/vaccinehj2021Production Animal Studie

Foot-and-mouth disease virus strains and examination of exposure factors associated with seropositivity of cattle herds in Nigeria during 2007–2009

New outbreaks of foot-and-mouth disease (FMD) occurred in cattle herds in Nigeria during 2007-2009. The objectives of the study reported here were (i) to identify current FMD virus strains circulating in cattle herds and (ii) to identify exposure factors associated with a seropositive diagnosis of FMD in cattle herds. This study provides evidence that FMD virus serotypes O, A and SAT-2 were co-circulating in cattle herds in Nigeria during 2007-2009. Cattle herds in a neighborhood affected with FMD had higher odds of being classified as seropositive to FMD, compared to herds that were in a neighborhood not affected with FMD (OR = 16.27; 95% CI = 3.61, 18.74; P < 0.01). Cattle herds that share water points along the trek routes with other cattle herds had higher odds of being classified as seropositive to FMD (adjusted OR = 4.15; 95% CI = 0.92, 18.74; P < 0.06). Results from this study can be used by veterinary services in Nigeria and neighboring countries to evaluate current or future FMD control and eradication programs.http://www.elsevier.com/locate/prevetme

Risk factors for farm-level African swine fever infection in major pig-producing areas in Nigeria, 1997-2011

African swine fever (ASF) is an economically devastating disease for the pig industry, especially in Africa. Identifying what supports infection on pig farms in this region remains the key component in developing a risk-based approach to understanding the epidemiology of ASF and controlling the disease. Nigeria was used for this matched case-control study, because there is perpetual infection in some areas, while contiguous areas are intermittently infected. Risk factors and biosecurity practices in pig farms were evaluated in association with ASF infection. Subsets of farms located in high-density pig population areas and high-risk areas for ASF infection were randomly selected for analysis. Most plausible risk factor variables from the univariable analysis included in the multivariable analysis include: owner of farm had regular contact with infected farms and other farmers, untested pigs were routinely purchased into the farm in the course of outbreaks, there was an infected neighbourhood, other livestock were kept alongside pigs, there was a presence of an abattoir/slaughter slab in pig communities, wild birds had free access to pig pens, tools and implements were routinely shared by pig farmers, there was free access to feed stores by rats, and feed were purchased from a commercial source Only the presence of an abattoir in a pig farming community (OR = 8.20; CI95% = 2.73; 24.63; P < 0.001) and the presence of an infected pig farm in the neighbourhood (OR = 3.26; CI95% = 1.20; 8.83; P = 0.02) were significant. There was a marginally significant negative association (protective) between risk of ASF infection and sharing farm tools and equipment (OR = 0.35; CI95% = 0.12; 1.01; P = 0.05). Of the 28 biosecurity measures evaluated, food and water control (OR = 0.14; CI95% = 0.04, 0.46; P < 0.001), separation/isolation of sick pigs (OR = 0.14; CI95% = 0.04, 0.53; P = 0.004) and washing and disinfection of farm equipment and tools (OR = 0.27; CI95% = 0.10, 0.78; P = 0.02) were negatively associated (protective) with ASF infection. Consultation and visits by veterinarian/paraveterinarians when animals were sick (OR = 8.11; CI95% = 2.13, 30.90; P = 0.002), and pest and rodent control were positively associated with ASF infection of Nigerian farms (OR = 4.94; CI95% = 1.84, 13.29; P = 0.002). The presentation of sick and unthrifty pigs for slaughter at abattoirs, farmers’ inadvertent role, an infected neighbourhood, a pig to pig contact, rodents and wild birds may contribute to infections of farms, whereas washing, disinfection of tools, food and water control, and separation of sick pigs reduces the likelihood of infections. Underlying reasons for these observations and strategies for control are discussed.http://www.elsevier.com/locate/prevetmedab201

Serological evidence of vaccination and perceptions concerning foot-and-mouth disease control in cattle at the wildlife-livestock interface of the Kruger National Park, South Africa

Communal livestock farming areas adjoining the Greater Kruger National Park Area within South Africa are part of the Foot-and-mouth disease (FMD) Protection Zone with Vaccination due to the proximity to wildlife reservoirs. FMD and its control affect the productivity of resource-poor farmers who often depend on livestock for their livelihoods. A cross-sectional study was performed with the objectives to evaluate the perceptions of farmers concerning FMD control, estimate the proportion of cattle with presumed protective antibody titres against FMD, as well as the proportion of herds with adequate herd immunity at the wildlife-livestock interface within Mpumalanga Province. One hundred and four farmers were interviewed with 73% (76/104) being cattle owners and the remainder hired cattle herders. The majority of respondents (79%, 82/104) reported a high level of satisfaction with the current animal health programmes in general. The educational level of the respondents varied by satisfaction level: the median (interquartile range; IQR) education level was standard 9 (2–12) for non-satisfied respondents, standard 3 (0–6) for little satisfied and standard 7 (2–11) for very satisfied respondents (P = 0.036). Animals are not always treated at FMD inspections points, but satisfied respondents were more likely to seek veterinary assistance (P = 0.001). The majority of respondents (92%, 96/104) identified the African buffalo (Syncerus caffer) as a risk factor for FMD outbreaks. Liquid-phase blocking ELISA antibody titres ≥1.6log10 were used to indicate positive serology secondary to FMD vaccination. At the time of sampling and relative to this threshold, 23% (95% confidence interval (CI): 12%–34%) of the sampled cattle had positive serology to SAT-1, 41% (95%CI: 33%–48%) to SAT-2 and 29% (95%CI: 19%–39%) to SAT-3. The median (IQR) time between the previous vaccination and sampling was 189 (168–241) days. The sampled cattle had a longer inter-vaccination interval as scheduled by state veterinary services and antibody levels were low at the time of the study. The majority of respondents expressed high satisfaction with the currently applied FMD vaccination programme, which provides an opportunity for progressive adaption of animal health programmes within the study area.This work was funded by contract agreement with the Peace Parks Foundation (Project No. A0U199), with additional support from the Research Development Programme (Project No. A0T384) at the University of Pretoria and Incentive Funding for Rated Researchers from the National Research Foundation (Project No. 76734).http://www.elsevier.com/locate/prevetmedhj2019Production Animal Studie

Transmission dynamics and control of Ebola virus disease outbreak in Nigeria, July to September 2014

We analyse up-to-date epidemiological data of the Ebola virus disease outbreak in Nigeria as of 1 October 2014 in order to estimate the case fatality rate, the proportion of healthcare workers infected and the transmission tree. We also model the impact of control interventions on the size of the epidemic. Results indicate that Nigeria’s quick and forceful implementation of control interventions was determinant in controlling the outbreak rapidly and avoiding a far worse scenario in this country.The Lundbeck Foundation and the Research And Policy for Infectious Disease Dynamics program (RAPIDD) of the United States Department of Homeland Security for sponsorship of LS. CV and GC acknowledge the financial support from the Division of International Epidemiology and Population Studies, The Fogarty International Center, United States National Institutes of Health, funded in part by the Office of Pandemics and Emerging Threats at the United States Department of Health and Human Services. GC also acknowledges support from grant NSF grant 1414374 as part of the joint NSF-NIH-USDA Ecology and Evolution of Infectious Diseases programme, United Kingdom Biotechnology and Biological Sciences Research Council grant BB/M008894/1 and grant number 1318788. III: Small: Data Management for Real-Time Data Driven Epidemic simulation.http://www.eurosurveillance.orgam201

Clinical presentation of FMD virus SAT1 infections in experimentally challenged indigenous South African goats

Foot-and-mouth disease (FMD) is a transboundary animal disease that has a major impact on livestock production and trade. Foot-and-mouth disease virus (FMDV) is a single-stranded RNA virus that infects cloven-hoofed livestock and wildlife. The susceptibility of South African indigenous goats to FMDV Southern African Territories 1 (SAT1) was investigated after experimental challenge with a mixed SAT1 virus pool. In this study, we present the clinical manifestation of FMDV in five naive goats challenged via the intra-dermolingual route with 104.57 50% tissue culture infective dose (TCID50) FMDV virus pool containing SAT1 SAR/8/10, SAR/10/10 and SAR/21/10. The clinical responses of two vaccinated unchallenged goats maintained as in-contacts are also presented. Clinical scoring of FMDV infection and daily rectal temperatures were recorded and temperatures ≥40 °C were defined as fever. All five challenged goats developed fever within 48 h post challenge with a median fever duration of 5 days. The two unchallenged goats developed fever at 5 and 9 days post-contact with FMD lesions appearing at 4 and 8 days post-contact. Additional clinical signs observed included nasal discharge, ulcerative oral mucosal lesions of the lip and ulcerative interdigital cleft lesions. The pooled FMDV SAT1 infection caused mild clinical signs and natural transmission to reduced-dose vaccinated in-contact indigenous South African goats occurred.The National Research Foundation (NRF), South Africa (Grant Numbers 90578 and 76734) with additional funding from the Peace Parks Foundation, under a contract grant agreement (Project #A0U199).http://www.elsevier.com/locate/smallrumres2020-11-01hj2020Production Animal Studie