Foot-and-mouth Disease In Cattle Research Articles

Economic losses due to foot-and-mouth disease (FMD) in Ethiopian cattle

Ethiopia’s cattle population is among the largest in Africa and is burdened by frequent foot-and-mouth disease (FMD) outbreaks. FMD is caused by several distinct and highly contagious viral strains that can result in acute disease in cattle, causing losses in productivity and impeding international trade. This economic simulation study considered four main sources of losses due to FMD in cattle: reduced milk yield, draft power yield, fertility, and increased mortality. Economic losses were estimated per case across age-sex strata in 89 Ethiopian administrative zones for the years 2010–2021 using a wide range of data to estimate distributions for 30 input variables in a series of Monte Carlo simulations. It was estimated that an average case of FMD in Ethiopian cattle results in losses (mean values reported followed 95 % confidence intervals in brackets) of US dollars (USD) 11 (USD 7–USD 16) per case. Losses resulting from an average outbreak were estimated to be USD 2300 (USD 1400–USD 3300), while national annual losses were estimated to be USD 0.9 Mil. (USD 0.2 Mil.–USD 2.3 Mil.). Per cow-year, based on a national cow population of approximately 39 Mil. head, these estimated annual losses are equivalent to losses of only USD 0.02 (USD 0.01–USD 0.06). Nationally, these losses were significantly less than previously estimated in the literature, with currently estimated losses more accurately reflecting the economic burden of FMD in Ethiopian cattle over the past decade. The relatively small estimated losses suggest that control efforts based on widespread vaccination in countries with primarily extensive cattle production systems, such as Ethiopia, are unlikely to be economically sound. Sensitivity analyses suggested losses would be far greater in intensive systems, and that certainty surrounding incidence rates is paramount to the formulation of economically sound animal healthpolicy in regions with endemic FMD.

Prophylactic treatment with PEGylated bovine IFNλ3 effectively bridges the gap in vaccine-induced immunity against FMD in cattle.

Foot-and-mouth disease (FMD) is a vesicular disease of cloven-hoofed animals with devastating economic implications. The current FMD vaccine, routinely used in enzootic countries, requires at least 7 days to induce protection. However, FMD vaccination is typically not recommended for use in non-enzootic areas, underscoring the need to develop new fast-acting therapies for FMD control during outbreaks. Interferons (IFNs) are among the immune system's first line of defense against viral infections. Bovine type III IFN delivered by a replication defective adenovirus (Ad) vector has effectively blocked FMD in cattle. However, the limited duration of protection-usually only 1-3 days post-treatment (dpt)-diminishes its utility as a field therapeutic. Here, we test whether polyethylene glycosylation (PEGylation) of recombinant bovine IFNλ3 (PEGboIFNλ3) can extend the duration of IFN-induced prevention of FMDV infection in both vaccinated and unvaccinated cattle. We treated groups of heifers with PEGboIFNλ3 alone or in combination with an adenovirus-based FMD O1Manisa vaccine (Adt-O1M) at either 3 or 5 days prior to challenge with homologous wild type FMDV. We found that pre-treatment with PEGboIFNλ3 was highly effective at preventing clinical FMD when administered at either time point, with or without co-administration of Adt-O1M vaccine. PEGboIFNλ3 protein was detectable systemically for >10 days and antiviral activity for 4 days following administration. Furthermore, in combination with Adt-O1M vaccine, we observed a strong induction of FMDV-specific IFNγ+ T cell response, demonstrating its adjuvanticity when co-administered with a vaccine. Our results demonstrate the promise of this modified IFN as a pre-exposure prophylactic therapy for use in emergency outbreak scenarios.

Seroprevalence and molecular detection of foot and mouth disease virus in cattle in selected districts of Wolaita Zone, Southern Ethiopia

Foot and mouth disease (FMD) is a highly contagious, endemic, and acute viral cattle ailment that causes major economic damage in Ethiopia. Although several serotypes of the FMD virus have been detected in Ethiopia, there is no documented information about the disease's current serostatus and serotypes circulating in the Wolaita zone. Thus, from March to December 2022, a cross-sectional study was conducted to evaluate FMDV seroprevalence, molecular detection, and serotype identification in three Wolaita Zone sites. A multistage sample procedure was used to choose three peasant associations from each study region, namely Wolaita Sodo, Offa district, and Boloso sore district. A systematic random sampling technique was employed to pick 384 cattle from the population for the seroprevalence research, and 10 epithelial tissue samples were purposefully taken from outbreak individuals for molecular detection of FMDV. The sera were examined using 3ABC FMD NSP Competition ELISA to find antibodies against FMDV non-structural proteins, whereas epithelial tissue samples were analyzed for molecular detection using real-time RT-PCR, and sandwich ELISA was used to determine the circulating serotypes. A multivariable logistic regression model was used to evaluate the associated risk variables. The total seroprevalence of FMD in cattle was 46.88% (95% CI 41.86–51.88), with Wolaita Sodo Town having the highest seroprevalence (63.28%). As a consequence, multivariable logistic regression analysis revealed that animal age, herd size, and interaction with wildlife were all substantially related to FMD seroprevalence (p < 0.05). During molecular detection, only SAT-2 serotypes were found in 10 tissue samples. Thus, investigating FMD outbreaks and identifying serotypes and risk factors for seropositivity are critical steps in developing effective control and prevention strategies based on the kind of circulating serotype. Moreover, further research for animal species other than cattle was encouraged.

Seroprevalence and Associated Risk Factors of Foot and Mouth Disease in Selected Woredas of the West Omo Zone, Southwest Ethiopia.

Aim and Background: Foot and Mouth Disease (FMD) is a prioritized transboundary animal disease, endemic in Ethiopia, and it has a high impact on cattle production and trade nationally and internationally. Methods: To ascertain the sero-prevalence and identify the exposure factors connected to a seropositive FMD in cattle, a cross-sectional study was conducted in three weredas of the West Omo Zone from January 2022 to February 2022. Multistage sampling was used to take one study wereda based on agroecology from the highland, midland, and lowland of the zone. Selection of cattle herd and blood samples from cattle were taken by using a simple random method. The Statistical Package for Social Science Version 25 was used to analyze the pertinent data once it had been entered and coded into Microsoft Excel. Results: The study area's FMD seroprevalence for individual cattle and at the herd level was 5.3% with a 95% confidence interval (3.51%–7.99%) and 77.78% (n= 9), respectively. The high herd level recorded during the current study was evidence that the disease has spread throughout the zone. Multinomial logistic regression analysis showed the age of the animal and study wereda are significantly(p&lt;0.05) associated with the sero-prevalence of FMD in this study. High cattle movement to big markets and long exposure of old cattle to the disease may contribute to the significant association of the disease with these risk factors. Conclusion: This study showed that herd-level FMD seropositivity is high, necessitating the identification of specific FMD serotypes and the commencement of appropriate FMD prevention and control strategies in the zone.

Bovine Sero- surveillance of Foot- and – Mouth Disease in Four States in Nigeria

Animals with cloven hooves are susceptible to highly contagious foot and mouth disease (FMD). FMD epidemics have affected several underdeveloped countries, including Nigeria. The migration of pastoralist animals has been linked to FMD transmission in Nigeria, and surveillance is essential for assessing the threat and impact of FMD, as well as the emergence of PCP-FMD. Here, we report the sero-surveillance of FMD in cattle in four states in Nigeria in 2019. Sera collected from four states (Anambra, Enugu, Imo, and Katsina) were tested for antibodies against FMD non-structural protein (NSP), with an overall prevalence of 45%. Significantly higher seroprevalence was recorded in Imo (63%), followed by Kastina (56%), Anambra (29%), and Enugu (6%). An overall serotype-specific prevalence of 81%, 35 %, 50 %, and 35% was recorded for serotypes O, A, 50% for SAT 2, and SAT 1, respectively. Furthermore, circulating antibodies against four serotypes of FMDV were found in 16% of sera samples, 20% had antibodies against three circulating serotypes, 33% had antibodies against two serotypes, and 25% showed exposure to only one serotype, indicating exposure to multiple FMD serotypes. These findings demonstrate the presence of FMDV antibodies in cattle across all surveyed states, which may be related to the presence of multiple FMDV serotypes (O, A, SAT1and SAT2) and concurrent co-infection in these states. Therefore, there is a need for the continuous surveillance of FMD in Nigeria. This will help ascertain the burden of the disease and enable the implementation of necessary control measures to stop its potential transmission and further spread. This sero-surveillance data expands our understanding of the FMD situation in Nigeria and is crucial for determining the country’s FMD risk in order to advance the PCP-FMD.

Immune response against lumpy skin disease after simultaneous vaccination of cattle with sheep pox and goat pox and foot and mouth disease vaccines

Foot and mouth disease (FMD) and Lumpy skin disease (LSD) are contagious viral diseases that cause significant economic damage in the livestock industry of countries. Cattle are vaccinated two times a year with FMD and sheep pox and goat pox vaccines (SGP) within 30-day intervals to combat both diseases in Türkiye. However, vaccinations in different periods increase vaccination costs, labor, and distress on animals. Therefore, it was aimed to determine the effects of simultaneous vaccination of FMD and SGP vaccines on the immunity against LSD and FMD in cattle. For this purpose, animals were divided into 4 groups; SGP vaccinated group (Group 1, n = 10), FMD vaccinated group (Group 2, n = 10), FMD and SGP simultaneously vaccinated group (Group 3, n = 10), and the unvaccinated control group (Group 4, n = 6). Blood samples were collected and analyzed to detect the antibody response against the LSD via Capripoxvirus (CaPV) ELISA and FMD by Virus Neutralisation test (VNT) and Liquid Phase Blocking ELISA (LPBE). A live virus challenge study was performed to determine the immune response against LSD. The mean antibody titers were determined protective levels on 28 days post vaccination (DPV) against FMDV serotypes O and A, respectively. The logarithmic difference of skin lesions was calculated log10 titer > 2.5. LSD genome could not be detected in the blood, eyes, and nose swap samples of the challenged animals on the 15th day via PCR. In conclusion, adequate protective immune response was provided against LSD when the SGP and FMD vaccines were used simultaneously in cattle.

Foot and Mouth Disease in Cameroon: A Systematic Review to Support its Progressive Control

Foot-and-mouth disease (FMD) is an infectious viral transboundary disease of even-toed animals, caused by the foot-and-mouth disease virus (FMDV). The objective of this paper is to provide reviewed data on the epidemiology, risks, control and the existing gaps on FMD in Cameroon from 1990 to 2021 to support its progressive control. Relevant and available documents (n = 45) on FMD in Cameroon such as peer-reviewed papers (n = 27), dissertations (n = 11), conferences (n = 5) and technical reports (n = 2) were used. Studies on the molecular and serological epidemiology, the role of carrier/mobile animals, the evaluation of immune-cross protection between serotypes and the quantification of serotype-specific transmission parameters using mathematical models have been discussed. The environmental drivers of FMD in cattle markets, abattoir and herd-level, as well as risk factors such as husbandry practices, communal grazing, regional/international livestock trading system, transhumance and fomites, are presented. As international borders remain porous with poor FMD monitoring infrastructure at veterinary checkpoints in a country with no candidate vaccine, vaccination program and commercial vaccines available, farmers are left with no option other than to manage the disease with traditional formulations and veterinary pharmaceuticals mostly antibiotics. Tri-Solfen® (TS), a wound dressing formulation was efficient in managing FMD in Cameroon. The current gaps in FMD knowledge in Cameroon are presented. There is a need for a comprehensive epidemiological study in the major cattle rearing regions of Cameroon. A regional study to identify all the risk factors for the transmission of FMD is required. A socio-economic impact study of FMD is required in Cameroon.

Foot-and-mouth disease in Cameroon: A systematic review to support its progressive control

Foot-and-mouth disease (FMD) is an infectious viral transboundary disease of even-toed animals, caused by the foot-and-mouth disease virus (FMDV). The objective of this paper is to provide reviewed data on the epidemiology, risks, control and the existing gaps on FMD in Cameroon from 1990 to 2021 to support its progressive control. Relevant and available documents (n=45) on FMD in Cameroon such as peer-reviewed papers (n=27), dissertations (n=11), conferences (n=5) and technical reports (n=2) were used. Studies on the molecular and serological epidemiology, the role of carrier/mobile animals, the evaluation of immune-cross protection between serotypes and the quantification of serotype-specific transmission parameters using mathematical models have been discussed. The environmental drivers of FMD in cattle markets, abattoir and herd-level, as well as risk factors such as husbandry practices, communal grazing, regional/international livestock trading system, transhumance and fomites, are presented. As international borders remain porous with poor FMD monitoring infrastructure at veterinary checkpoints in a country with no candidate vaccine, vaccination program and commercial vaccines available, farmers are left with no option other than to manage the disease with traditional formulations and veterinary pharmaceuticals mostly antibiotics. Tri-Solfen® (TS), a wound dressing formulation was efficient in managing FMD in Cameroon. The current gaps in FMD knowledge in Cameroon are presented. There is a need for a comprehensive epidemiological study in the major cattle rearing regions of Cameroon. A regional study to identify all the risk factors for the transmission of FMD is required. A socio-economic impact study of FMD is required in Cameroon.

Subdistrict-Level Reproductive Number for Foot and Mouth Disease in Cattle in Northern Thailand.

Foot and mouth disease (FMD) is an important contagious transboundary disease that causes a significant economic loss for several countries. The FMD virus (FMDV) can spread very rapidly by direct and indirect transmission among susceptible animals. The complexity and magnitude of FMDV transmission at the initial stages of the epidemic can be expressed by the basic reproductive number (R0), and furthermore, control strategies can be assessed by the estimation of the effective reproductive number. In this study, we aimed to describe FMD outbreaks among smallholder cattle farms by subdistricts in the northern Thailand and compute the effective reproductive number for outbreaks caused by FMDV serotype O and overall serotypes, including serotype O, serotype A, and unidentified serotype, at the subdistrict level (Rsd) using an epidemic doubling time method. Field data of FMD outbreaks during 2015–2017 that affected 94 subdistricts in northern Thailand were assessed to estimate the Rsd. Results showed that 63.38% (90/142) of the FMD outbreak episodes in cattle were caused by FMDV serotype O. The average doubling time and the Rsd estimated of the outbreaks caused by FMDV serotype O and overall serotype were 2.80 and 4.67 months, and 1.06 and 1.04, respectively. Our results indicated that transmission of FMD in cattle at the subdistrict level in northern Thailand was not controlled (Rsd > 1), which indicates the endemicity of the disease in the region. Although control measures are in place, the results from this study highlighted the need for enhancing FMD monitoring and control strategies in northern Thailand.

Foot and Mouth Disease (FMD) incidence in cattle and buffaloes and its associated farm-level economic costs in endemic India

The study investigated the important epidemiological parameters and farm-level economic costs of FMD incidence in cattle and buffaloes during 2013−14 to 2015−16 in various states of India. Multistage random sampling procedure was adopted for the primary survey and data was collected through face-to-face personal interview from 18,609 cattle and buffalo rearing farm households from 123 districts across twelve states and one Union Territory. Besides epidemiological parameters, different farm-level direct and indirect loss associated with FMD was assessed at disaggregated level (states) by employing deterministic mathematical models. Highest number of affected villages and disease incidence was observed in non- FMD control programme (FMD-CP) implemented Madhya Pradesh and Assam states, respectively whereas negligible incidence was in FMD-CP implemented Punjab state. The disease incidence was high during 2013−14 and declined during 2014−15 and 2015−16, respectively implied severe incidence scenario (2013−14) succeeded by moderate (2014−15) and mild (2015−16) scenarios. The crossbred and high productive animals were severely affected than local breeds whereas on sexwise and agewise comparison revealed higher incidence in females and adult animals. During severe incidence scenario, milk loss/animal ranged from USD 6.87–47.44, 18.42–125.88, 16.33–91.43, and 27.17–123.62; mortality loss/animal ranged from USD 32.61–804.27, 30.76–577.7, 65.36–502.2, and 188.04–413.7; distress sale loss/animal ranged from USD 3.22–188.63, 64.34–519.3, 214.47–341.8, and 209.11–450.3; and opportunity cost of labour/animal from USD 5.49–54.29, 5.49–67.78; 7.95–31.37 and 9.83–72.38 in indigenous cattle, crossbred cattle, local and improved buffalo, respectively. The estimated draught power loss/animal varied from USD 39.46–142.94 with least being in Madhya Pradesh and highest in Assam states whereas the median treatment cost/animal was USD 9.18 and USD 27.07 in indigenous cattle and upgraded buffaloes, respectively. The total farm-level economic loss projected due to FMD in cattle and buffaloes in India was USD 3159 million (INR 221,110 million), USD 270 million (INR 18,910 million) and USD 152 million (INR 10,610 million), respectively during the severe, moderate and mild incidence scenarios at 2015−16 constant prices. The loss varied across the states, and in severe incidence scenario, the country might lose USD 3.2 billion/year and hence, the bi-annual vaccination schedule need to be strictly implemented in all the states. Besides timely vaccination coverage, managing unabated animal movement, educating and motivating the farmers to vaccinate their animals might reduce the incidence and consequential losses to various stakeholders in endemic states like India.

Economic Impact of FMD in cattle and buffaloes in India

In India, among various diseases that limit livestock production, Foot and Mouth Disease (FMD) stands first and affects thousands of animals every year. The estimation of loss due to FMD is of paramount importance for designing appropriate control plans. The economic impact studies on various livestock diseases including FMD are very minimal and hence this study assessed the economic loss due to FMD in cattle and buffaloes in few states and overall loss in the country. The total loss estimated comprise of milk yield reduction, unavailability of draught power, distress sale, treatment cost, mortality and opportunity cost of labour based on primary survey undertaken in 10 states and one Union territory. The results revealed that there was variation in loss levels between species and among the study states due to variation in disease incidence and severity levels, productive capacity of the animals, animal health infrastructure in the respective states, etc. The total estimated loss due to FMD in cattle and buffalo was INR 20,897 crore during 2013-14 with wide variation in magnitude across the states studied. The study provided empirical evidence of loss due to FMD in cattle and buffaloes in few states and overall loss in the country.

The first molecular detection of Clostridium perfringens from pneumonic cases associated with foot and mouth disease in cattle and buffalo in Egypt.

Panting syndrome and respiratory infection have been recorded in complicated cases of foot and mouth disease (FMD) in cattle. However, investigations on the causative agents of respiratory disease in such cases are scarce. In this study, 30 animals (13 buffalo and 17 cattle) suffering from respiratory distress associated with signs of FMD were examined. Serum samples were collected and FMD infection was confirmed. Bacteriological examination of lungs from eight necropitized cases revealed the presence of C. perfringens. Multiplex polymerase chain reaction (mPCR) was performed on the positive samples followed by sequencing analysis. The alpha toxin gene (plc) of C. perfringens was identified in six cases. The present investigation highlights the role of clostridial infection as a complication of FMD in cattle and buffalo. This is the first report identifying the C. perfringens toxins from lung of animals with respiratory distress associated with FMD infection.

Electrocardiogram and serum cardiac biomarkers changes in FMD in cattle

This study was designed to evaluate serum and electrocardiographic (ECG) changes in cattle with foot-and-mouth disease (FMD). Thirty-two cows with clinical signs of FMD and 13 healthy cows were randomly enrolled. After blood sampling, ECG was performed on 23 of the 32 ill cows. Serum circulatory troponin I (cTnI), CPK, LDH, and CK-MB activities were determined in the patient and control groups. Arrhythmias including ventricular tachycardia (VT), sinus tachycardia (ST), atrial fibrillation (AF), and premature ventricular complex (PVC) were seen in 4, 4, 2, and 1 of the patients, respectively. The patients had higher cTnI levels than the control group (P = 0.05). A significant rise in cTnI was observed in patient cows with VT (0.86 ± 0.33; P < 0.01) and AF (0.22 ± 0.01 ng/mL; P < 0.05) in comparison with the control group (0.14 ± 0.04 ng/mL). The most significant finding of this study was the death of all of the cows with VT. It appears that the cause of death in the cows with VT was cardiac impairment, which was marked by serum cTnI elevation. It can be concluded that cows with VT have a grave prognosis. In some FMD cases with an increase in cTnI, AF was also observed, but with a fairly good prognosis.

English

Cross-sectional study was conducted from December, 2008 to April, 2009 to determine the sero prevalence of foot and mouth disease (FMD) virus in West and South West Shoa zones of Oromia regional state, central Ethiopia. The samples were processed with the 3 ABC ELISA kits that can able to identify natural infected animal from vaccinated animals. From the total sera of 421 tested, the overall sero prevalence of FMD in cattle was 15.0% (63/421). The prevalence rate was higher (22%) in the South west shoa zone than West shoa zone (5.6%). The difference was statistically significant (&rho;&lt;0.05). At district level, the highest sero prevalence were recorded at Dawo (26.7%), Alemgana (26.2%), Kokir (24.4%) and Haramaya (21.4%) districts, which were located at south west shoa zone. The difference among districts were statistically significant (&rho;&lt;0.05). Statistically difference was also observed between different age groups (&rho;&lt;0.05); being higher in adult (19.3%) followed by calves (9.3%). The sero prevalence of male and female were 16.0 and 14.1%, respectively, and which was not statistically significant (&rho;&gt;0.05). The sero prevalence of FMD was found higher in mid highland (16.8%) than highland attitude (6.7%) which was statistically significant (&rho;&lt;0.05). The result of this study indicated that FMD is highly prevalent in the South West Shoa zone than West Shoa zone due to contact of different origin of animals, and free animals movement in search of feed and water in zone. Age and attitude were also found as an important risk factor for the diseases. Finally, it is recommended that, sero typing of the virus circulating in the study area should be undertaken for effective control of the disease. Key words: FMD, Sero prevalence, West Shoa, South west shoa, 3 ABC ELSA.

An appraisal on the occurrence of foot-and-mouth disease virus serotypes in cattle and buffaloes, Pakistan.

Foot-and-mouth disease (FMD) is a livestock disease that has serious economic repercussions. Here, we report the laboratory results for samples from suspected outbreaks that were sent for confirmation of FMD in Pakistan. From January 2010 to December 2011, 132 suspected outbreaks were investigated, and samples from 58 out of the 76 outbreaks sent to the National Veterinary Laboratory (NVL) were positive. The highest proportion of positives were of serotype O (65.52 %), followed by serotype A (24.14 %) and serotype Asia-1 (10.35 %), whereas amongst the samples sent to the World Reference Laboratory, Pirbright, UK (WRL), samples from 48 out of 56 outbreaks were confirmed to be FMD positive, with the following serotypes identified: O (56.25 %), Asia-1 (37.50 %) and A (6.25 %). The outbreaks affected cattle, buffalo and mixed (cattle and buffalo) herds at rates of 91, 70 and 76 %, respectively. The trend of positive outbreaks was higher in the months of winter and late spring (November to April). Although the serotype O isolates and some of the serotype A isolates from the field samples resembled the vaccine strains (r-value ≥ 0.3), this was not the case for the Asia-1 isolates. These results help to improve our understanding of the occurrence and distribution of FMD in cattle and buffaloes in Pakistan and to provide baseline information for the FMD progressive control program in the country.

A serological survey for antibodies against foot-and-mouth disease virus (FMDV) in domestic pigs during outbreaks in Kenya

Foot-and-mouth disease (FMD) is endemic in Kenya and has been well studied in cattle, but not in pigs, yet the role of pigs is recognised in FMD-free areas. This study investigated the presence of antibodies against FMD virus (FMDV) in pigs sampled during a countrywide random survey for FMD in cattle coinciding with SAT 1 FMDV outbreaks in cattle. A total of 191 serum samples were collected from clinically healthy pigs in 17 districts. Forty-two of the 191 sera were from pigs vaccinated against serotypes O/A/SAT 2 FMDV. Antibodies against FMDV non-structural proteins were found in sera from 30 vaccinated and 71 non-vaccinated pigs, altogether 101/191 sera (53%), and 91% of these (92/101) also had antibodies measurable by serotype-specific ELISAs, predominantly directed against SAT 1 with titres of 10-320. However, only five high titres against SAT 1 in vaccinated pigs were confirmed by virus neutralisation test (VNT). Due to high degree of agreement between the two ELISAs, it was concluded that positive pigs had been infected with FMDV. Implications of these results for the role of pigs in the epidemiology of FMD in Kenya are discussed, and in-depth studies are recommended.

Development of a Foot-and-Mouth Disease Virus Serotype A Empty Capsid Subunit Vaccine Using Silkworm (Bombyx mori) Pupae

Foot-and-mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals that inflicts severe economic losses in the livestock industry. In 2009, FMDV serotype A caused outbreaks of FMD in cattle in China. Although an inactivated virus vaccine has proven effective to control FMD, its use may lead to new disease outbreaks due to a possible incomplete inactivation of the virus during the manufacturing process. Here, we expressed the P1-2A and the 3C coding regions of a serotype A FMDV field isolate in silkworm pupae (Bombyx mori) and evaluated the immunogenicity of the expression products. Four of five cattle vaccinated with these proteins developed high titers of FMDV-specific antibody and were completely protected against virulent homologous virus challenge with 10,000 50% bovine infectious doses (BID50). Furthermore, the 50% bovine protective dose (PD50) test was performed to assess the bovine potency of the empty capsid subunit vaccine and was shown to achieve 4.33 PD50 per dose. These data provide evidence that silkworm pupae can be used to express immunogenic FMDV proteins. This strategy might be used to develop a new generation of empty capsid subunit vaccines against a variety of diseases.

The therapeutic effect of Tarentula cubensis extract (Theranekron®) in foot-and-mouth disease in cattle: a randomised trial in an endemic setting

Foot-and-mouth disease (FMD) is a contagious viral disease of ruminant animals. Eradication of disease in western countries is by slaughter of infected and in contact animals but this is not possible in endemic countries. There is no standard treatment for FMD in endemic countries, but anti-inflammatory drugs and mild disinfectant and protective dressing to inflamed areas to prevent secondary infection is recommended. A randomised controlled clinical trial of a homeopathic preparation of Tarentula cubensis (Theranekron®) was conducted during an outbreak of FMD in cattle in Iran. A single subcutaneous injection of Theranekron® was used as sole treatment in 50 infected animals (treatment group). The control group comprised 15 infected animals treated with standard medication including: daily injection of flunixin meglumine and oxytetracycline and daily dressing of lesions with 4% sodium carbonate. Systemic and local signs were recorded over 14 days. Rectal temperature in treatment group subsided to normal range within 1 day of homeopathic treatment, and was significantly lower in test group than in control group on several successive days (P < 0.05). Healing of inflamed mucosal areas and appetite score of the treatment was significantly better than control during first 3 days of treatment (P < 0.05). It appears that Theranekron® is effective for treatment of systemic and local signs of FMD-infected cattle. Further research is justified.

Experimental studies with foot-and-mouth disease virus type Asia-1, responsible for the 2005 epidemic in China

This study was carried out to investigate the biological characteristics of the foot-and-mouth disease (FMD) virus strain Asia-1 China/2005, which is responsible for the 2005 epidemic in China. The result showed that this strain is not host restricted, and could not only cause FMD in cattle and sheep but also in pigs by either inoculation or direct contact.

Adenovirus-Mediated Type I Interferon Expression Delays and Reduces Disease Signs in Cattle Challenged with Foot-and-Mouth Disease Virus

Foot-and-mouth disease (FMD) is an economically important disease of livestock. Eliminating FMD outbreaks in previously disease-free countries often relies on restriction of animal movement and massive slaughter of infected and in-contact susceptible animals. To develop a more effective and humane FMD control strategy, we explored the possibility of using type I interferon (IFN-alpha/beta) as a novel anti-FMD agent. We have demonstrated previously that swine inoculated with replication-defective human adenovirus type 5 (Ad5) vector expressing porcine IFN-alpha (Ad5-PoIFN-alpha) were completely protected from FMD virus (FMDV) challenge. To extend this approach to bovines, we constructed Ad5 vectors that express bovine IFN-alpha or IFN-beta (Ad5-BoIFN-alpha and Ad5-BoIFN-beta). Cells infected with these viruses produced high levels of biologically active BoIFN-alpha/beta, but despite expression in vitro, no detectable IFN-induced biologic activity was found in cattle inoculated with Ad5-BoIFN-alpha. Because PoIFN-alpha inhibits FMDV replication in bovine cells, we evaluated the potential use of PoIFN-alpha against FMD in cattle. In cattle inoculated with Ad5-PoIFN-alpha, the appearance of vesicles was delayed after challenge with FMDV and disease was less severe than in control animals. One Ad5-PoIFN-alpha-inoculated animal never developed clinical disease. Similarly, although all the Ad5-PoIFN-alpha-inoculated animals developed viremia, it was delayed for 1 day as compared with the control group. These results suggest that in vivo expression of PoIFN-alpha partially protected cattle from FMD.