Epidemiology of foot and mouth disease in Karnataka state, India: a retrospective study

Livestock vaccination programme participation among smallholder farmers on the outskirts of National Parks and Tiger Reserves in the Indian states of Madhya Pradesh and Assam

Effective livestock vaccination has the potential to raise prosperity and food security for the rural poor in low and middle income countries. To understand factors affecting access to vaccination services, and guide future policy, smallholder farmers in three locations in India were questioned about vaccination of their cattle and buffalo, with particular reference to foot and mouth disease (FMD), haemorrhagic septicaemia (HS) and blackquarter (BQ). In the three regions 51%, 50%, and 31% of respondents reported vaccinating their livestock; well below any threshold for effective population level disease control. However, within the third region, 65% of respondents in villages immediately surrounding the Kaziranga National Park reported vaccinating their cattle. The majority of respondents in all three regions were aware of FMD and HS, awareness of BQ was high in the Kanha and Bandhavgarh regions, but much lower in the Kaziranga region. The majority of respondents had positive attitudes to vaccination; understood vaccination protected their animals from specific diseases; and wished to immunise their livestock. There was no significant association between the age or gender of respondent and the immunisation of their livestock. Common barriers to immunisation were: negative attitudes to vaccination; lack of awareness of date and time of vaccination events; and difficulty presenting animals. Poor access to vaccination services was significantly associated with not vaccinating livestock. Fear of adverse reactions to vaccines was not significantly associated with not vaccinating livestock. Respondents who reported that vets or animal health workers (AHWs) were their main source of animal health knowledge were significantly more likely to have immunised their livestock in the last twelve months. Participants cited poor communication from vaccinators as problematic, both in publicising immunisation programmes, and explaining the purpose of vaccination. Where vaccinations were provided free of charge, farmers commonly displayed passive attitudes to accessing vaccination services, awaiting organised “immunisation drives” rather than seeking vaccination themselves. Based on these findings the following recommendations are made to improve participation and effectiveness of immunisation programmes. Programmes should be planned to integrate with annual cycles of: disease risk, agricultural activity, seasonal climate, social calendar of villages; and maximise efficiency for vaccinators. Dates and times of immunisation in each village must be well publicised, as respondents frequently reported missing the vaccinators. Relevant farmer education should precede immunisation programmes to mitigate against poor knowledge or negative attitudes. Immunisation drives must properly engage beneficiaries, particularly ensuring that services are accessible to female livestock keepers, and sharing some responsibilities with local farmers. Payment of a small monetary contribution by animal keepers could be considered to encourage responsibility for disease prevention, making vaccination an active process by farmers.

Seroprevalence and risk factors for foot-and-mouth disease in cattle in Baghlan Province, Afghanistan

A serological study of 376 cattle from 198 herds and a concurrent survey of farmers were undertaken in 53 villages in Khinjan, Doshi and Puli Khumri districts of Baghlan province, Afghanistan to determine the seroprevalence of Foot and Mouth Disease (FMD) and to identify risk factors for seropositive herds. A total of 419 cases of FMD were reported by the farmers in the year preceding the survey. The animal-level population seroprevalence was estimated at 42.0% (95% CI, 37.0-47.2). The seroprevalence increased with age in the sampled cattle (<2 years - 30.4%, 2-6 years - 40.3% and >6 years - 52.2%). Herds were more likely to be seropositive if the farmers: had purchased cattle in the year prior to the survey (OR = 2.6; 95% CI, 1.37-4.97); purchased ruminants from unknown (potentially risky) sources (OR = 2.13; 95% CI, 1.13-4.03); and sold milk to the market (OR = 1.99; 95% CI, 1.09-3.63). Herds that had been vaccinated had a lower odds of being seropositive (OR = 0.33; 95% CI, 0.68-0.66). This was the first epidemiological study of FMD in Baghlan province and the findings provide valuable direction for disease control on FMD in this and other provinces in Afghanistan.

Outbreak investigation of foot and mouth disease in Nangarhar province of war-torn Afghanistan, 2014

Afghanistan has long history of ongoing conflicts, resulting in massive destruction of the country's infrastructure. Illegal trade of livestock between Afghanistan and Pakistan boosted the spread of Foot & Mouth Disease (FMD). Current study was conducted to investigate outbreaks of FMD occurred between April-August 2014 in Nangarhar, Afghanistan. Descriptive data about suspected FMD cases were collected from the Civil Veterinary Hospital, Nangarhar to analyze spatio-temporal pattern of FMD. Case farms (n = 137) were selected from list of clinically confirmed FMD outbreaks available in the hospital. Control farms (n = 137) were enrolled from neighboring premises of case farms. The epidemic curve showed that the virus is continuously circulating among susceptible population. The mean age of the oldest lesion was 2.8 days. Foot & Mouth Disease was more likely to occur in female animals compared to male animals (p < 0.001). Farmers having no ability to clinically recognize FMD (OR 5.8, 95% CI 1.4-23.8); previously having any FMD case in herd (OR 11.8, 95% CI 3.0-45.8), farms where animals leave shed during day (OR 15.4, 95% CI 5.6-42.0), and farms, where neighboring farmers used to visit the premises (OR 3.5, 95% CI 1.2-9.9) were identified as risk factors. Current findings may be used to create awareness of concerned veterinary health authorities about FMD control.

In vitro antiviral efficacy of pleconaril and ribavirin on foot-and-mouth disease virus replication

Antiviral therapy is a promising strategy to control acute viral infections. FMDV causes an acute infection and the vaccination provides a protective immunity 7 days post immunization. If the infection is uncontained, then it affects the entire herd. In such circumstances, if antiviral drug is administered the infection can be checked in a herd. Ribavirin is known to cure persistently infected BHK21 cells with FMD virus. However, there have been no systematic studies on antiviral activity of ribavirin against FMDV at different time points with the application of ELISA, PCR or real-time PCR. Pleconaril is known to inhibit enteroviruses and rhinoviruses but has not been explored on FMDV. Hence, the present study evaluates the in vitro antiviral efficacy of pleconaril and ribavirin on FMDV replication. The maximum non-toxic concentrations (MNTC) of pleconaril and ribavirin for BHK21 cells respectively were 7.81 μg/50 μL and 15.62 μg/50 μL. Thus, drug concentrations below MNTC were tested for their antiviral activity against serial tenfold diluted FMDV O, A and Asia 1 serotypes. Pleconaril did not inhibit FMDV serotype O replication at 7.5 μg/50 μL based on CPE inhibition assay and this was further confirmed using sandwich ELISA, PCR/real-time PCR. On the other hand, ribavirin at 15.62 μg/50 μL inhibited the in vitro replication of FMDV O, A and Asia 1 and the inhibition was confirmed by serotype specific sandwich ELISA, PCR and real-time PCR assays. The inhibition was directly proportional to the concentration of ribavirin. Therefore, ribavirin could be explored for its in vivo efficacy as a potential therapeutic in the prevention of early spread of FMDV infection in a herd.

Outbreak investigations of foot and mouth disease virus in Nepal between 2010 and 2015 in the context of historical serotype occurrence

Foot and Mouth Disease (FMD) is endemic in Nepal and causes substantial economic losses in the livestock industry. The goal of this study was to perform an epidemiological analysis of FMD outbreaks reported to the Veterinary Epidemiology Center, Tripureshwor, Nepal during 2010-2015, in order to strengthen the National FMD Control Program. These current data were considered in the context of historical data on FMD virus (FMDV) serotypes detected in the country between 1965 and 2015. During 2010-2015, a total of 1333 livestock holdings reported FMD outbreaks in Nepal. On average, 71.2 animals were affected in each outbreak, with a case fatality rate of 3.6%. FMD was reported throughout the country, and the proportion of affected holdings was not significantly among eco-zones, regions, or species. The Hill eco-zone had the highest number of holdings affected (782), followed by Mountain (304), and Terai (247). When analysed by the developmental region, the Western (381) and Central (368) Developmental Regions had the highest numbers of holdings affected. Cattle were the most frequently affected species (39%), followed by buffalo (33%), and goats (19%). FMD occurred throughout the year, with peaks in winter (December/January) and in the pre-monsoon period (April/May). Between 1965 and 2015 FMDV serotype O had the highest prevalence (81%), followed by Asia-1 (11%), A (6%), and C (2%). Serotype C was not detected after 1996, and only serotype O was reported after 2011. These descriptive analyses provide critical landmarks to establish baselines, and document early progress of the ongoing Progressive Control Pathway of FMD (PCP-FMD) which could be useful in Nepal and other South Asian nations.

Serosurveillance of foot and mouth disease in Karnataka state, India: a 3 years study

A prospective serological investigation was conducted to determine the prevalence and distribution of foot-and-mouth disease (FMD), as well as to monitor the effectiveness of the FMD control programme (FMD-CP) through vaccination in Karnataka, India. Random serum samples were collected every year between May and August before the start of vaccination in 2011, and subsequently following two phases of vaccination in 2012 and 2013. Infection status (seroprevalence) was inferred by subjecting the sera to indirect r3AB₃ non-structural protein-ELISA, using kits developed by the Project Directorate on FMD, India. The seromonitoring of FMD-CP was carried out by detecting antibodies deemed to be protective in the pre- and post-vaccinal sera, using liquid-phase blocking-ELISA for structural proteins. The results revealed significant decrease in seroprevalence from 58 to 21 %, providing more definitive data supporting our earlier findings obtained through clinical observations (Hegde et al. in Virusdisease 25:504-509, 2014), and detecting active infection in some of the populations which were considered to be free based on passive surveillance. On the other hand, after four rounds of vaccination, a gradual and significant increase from 4.5 to 59 % of animals carrying antibody levels deemed to be protective was observed against all the three serotypes. The findings of this study could be useful for further strategizing to strengthen the ongoing FMD-CP in Karnataka State, India.