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Foot-and-mouth disease (FMD) is a severe and extremely contagious viral disease. Cows, sheep, goats, deer, pigs, and other animals with divided hooves are among the animals infected by the FMD viruu, which is a member of the Picornaviridae family and genus Aphtho virus. There are seven different serotypes of this virus: Asia-1, SAT1, SAT2, SAT3, A, O, and C. Heat, ultraviolet light, pH values of 6.5 or higher, gamma radiation, chemicals, and disinfecting agents all inactivate the virus; however, it remains virtually stable at below- freezing temperatures for a prolonged amount of time. Animals affected by this disease develop vesicular lesions on their tongue, dental pad, gums, cheeks, hard and soft palates, lips, nostrils, muzzle, interdigital region (between the hoof), and a coronary band. Viral infections can spread through the respiratory tract or via the oral cavity. Clinical manifestations of FMD are used to diagnose the disease, along with laboratory and epidemiological investigations. Due to the high morbidity linked to outbreaks, difficulties in the local adoption of more advanced production techniques, limitations on trade between countries, and expenses related to the implementation of control measures, FMD results in significant economic losses. FMD can be controlled and prevented through immunization, restrictions on animal migration, physical segregation from wildlife, and clinical therapy. However, FMD demonstrated challenges to control because of its complicated epidemiological nature, poor diagnostic capacity, and lack of cross-immunity between strains. Investigation is consequently essential to progressing the creation of a multivalent and effective vaccination. [ABSTRACT FROM AUTHOR]

Introduction: Foot and mouth disease (FMD) is a highly viral contagious disease and is prevalent in the majority of developing nations. Case report: The present study reported a foot and mouth disease Sat-2 outbreak in Al-Muthanna province in southern Iraq in March 2023. Three male Holstein Friesian cows, aged between 1 and 1.5 years and weighing approximately 550 ± 15 kg each, were affected. Clinical examination revealed symptoms, including fever, severe lameness, anorexia, depression, frothy salivation, and vesicular lesions on the mouth and feet. Confirmation of the Sat-2 serotype was achieved through serological testing and genotyping of the virus, conducted by the FMD Institute, Ankara, Türkiye. The Sat- 2 serotype was recognized by genotyping the virus and submitting SAT-2 VP1 sequences. The treatments for secondary infection prevention included Ceftifur (2.2 mg/kg) for 5 days, and flunixin meglumine (2.2 mg/kg) for 2 days. The other animals that were not exposed to infected animals were vaccinated against FMD. Rigorous biosecurity measures were implemented, involving thorough disinfection of the environment and quarantine of the infected animals. Direct contact between the farmer and other animals, particularly the sick ones, was completely avoided. After 2 weeks, all infected animals began to eat normally again, and clinical signs disappeared. Notably, other animals on the farm did not exhibit any signs of FMD. Conclusion: In conclusion, the findings of this study underscore the importance of biosecurity measures and vaccination in FMD prevention. Additionally, administering antibiotics and non-steroidal anti-inflammatory drugs for the prevention of secondary infections proves to be crucial. [ABSTRACT FROM AUTHOR]

Foot‐and‐mouth disease (FMD) is widely distributed in Sudan where outbreaks occur on an annual basis especially during the winter months (December‐February). This study aimed to increase our understanding of the epidemiological patterns of FMD in Sudan and connections to neighbouring countries by characterizing the genetic sequences of FMD viruses (FMDV) collected from samples collected in 10 Sudanese states over a 10‐year period (between 2009 and 2018). FMDV was detected in 91 of the 265 samples using an antigen‐detection ELISA. Three serotypes were detected: O (46.2%), A (34.0%), and SAT 2 (19.8%). Fifty‐two of these samples were submitted for sequence analyses, generating sequences that were characterized as belonging to O/EA‐3 (n = 17), A/AFRICA/G‐IV (n = 23) and SAT 2/VII/Alx‐12 (n = 12) viral lineages. Phylogenetic analyses provided evidence that FMDV lineages were maintained within Sudan, and also highlighted epidemiological connections to FMD outbreaks reported in neighbouring countries in East and North Africa (such as Ethiopia and Egypt). This study motivates continued FMD surveillance in Sudan to monitor the circulating viral lineages and broader initiatives to improve our understanding of the epidemiological risks in the region. [ABSTRACT FROM AUTHOR]

Viral recombination contributes to the emergence of novel strains with the potential for altered host range, transmissibility, virulence, and immune evasion. For foot-and-mouth disease virus (FMDV), cell culture experiments and phylogenetic analyses of field samples have demonstrated the occurrence of recombination. However, the frequency of recombination and associated virus–host interactions within an infected host have not been determined. We have previously reported the detection of interserotypic recombinant FMDVs in oropharyngeal fluid (OPF) samples of 42% (5/12) of heterologously superinfected FMDV carrier cattle. The present investigation consists of a detailed analysis of the virus populations in these samples including identification and characterization of additional interserotypic minority recombinants. In every animal in which recombination was detected, recombinant viruses were identified in the OPF at the earliest sampling point after superinfection. Some recombinants remained dominant until the end of the experiment, whereas others were outcompeted by parental strains. Genomic analysis of detected recombinants suggests host immune pressure as a major driver of recombinant emergence as all recombinants had capsid-coding regions derived from the superinfecting virus to which the animals did not have detectable antibodies at the time of infection. In vitro analysis of a plaque-purified recombinant virus demonstrated a growth rate comparable to its parental precursors, and measurement of its specific infectivity suggested that the recombinant virus incurred no penalty in packaging its new chimeric genome. These findings have important implications for the potential role of persistently infected carriers in FMDV ecology and the emergence of novel strains. [ABSTRACT FROM AUTHOR]

ABSTRACT: Foot-and-mouth disease represents an important barrier to the international commerce of animal products, potentially associated with significant economic losses. The systematic vaccination of bovines and buffaloes was fundamental for the eradication of this disease; however, the use of vaccines can lead to reactions at the application site. The objectives of this study were to evaluate the effects of the vaccination protocol to the production of dairy cows and to observe the occurrence of vaccinal reactions in the animals. At one property located in the municipality of Salvador do Sul, Rio Grande do Sul, 270 dairy cows were vaccinated against foot-and-mouth disease in May 2019. The vaccine was administered via a subcutaneous application using disposable syringes and needles for each animal. Inspection of the animals was performed before and 20 days after the vaccination to verify the presence of reactions to the vaccine. The study’s sample was set by convenience, including 203 lactating animals with or without bovine somatotropin (BST) administration during the data collection period, which was limited to 20 days before and 20 days after the vaccination. Milk production data was obtained through SmartDairy® HerdMetrix™ software, tabulated in electronic spreadsheets using Microsoft Excel® and processed using the program SAS®, considering a 5% significance level for mixed model statistical analysis. A total of 160 animals (78.82%) presented local lesions at the application site, even when the recommended vaccination practices were followed, suggesting that the high reaction power was provoked by the vaccinal components. In regards to milk production, a statistically significant (p

The presence of foot‐and‐mouth disease virus (FMDV) of the O/ME‐SA/Ind‐2001e sublineage within Pakistan was initially detected in two samples collected during 2019. Analysis of further serotype O FMDVs responsible for disease outbreaks in 2019–2020 in the country has now identified the spread of this sublineage to 10 districts within two separate provinces in North‐Eastern and North‐Western Pakistan. Phylogenetic analysis indicates that these viruses are closely related to those circulating in Bhutan, Nepal and India. The VP1 coding sequences of these viruses from Pakistan belong to three distinct clusters, which may indicate multiple introductions of this virus sublineage, although the routes of introduction are unknown. Vaccine matching studies against O1 Manisa, O 3039 and O TUR/5/2009 support the suitability of existing vaccine strains to control current field outbreaks, but further studies are warranted to monitor the spread and evolution of the O/ME‐SA/Ind‐2001e sublineage in the region. (145 words). [ABSTRACT FROM AUTHOR]

Viral recombination contributes to the emergence of novel strains with the potential for altered host range, transmissibility, virulence, and immune evasion. For foot-and-mouth disease virus (FMDV), cell culture experiments and phylogenetic analyses of field samples have demonstrated the occurrence of recombination. However, the frequency of recombination and associated virus–host interactions within an infected host have not been determined. We have previously reported the detection of interserotypic recombinant FMDVs in oropharyngeal fluid (OPF) samples of 42% (5/12) of heterologously superinfected FMDV carrier cattle. The present investigation consists of a detailed analysis of the virus populations in these samples including identification and characterization of additional interserotypic minority recombinants. In every animal in which recombination was detected, recombinant viruses were identified in the OPF at the earliest sampling point after superinfection. Some recombinants remained dominant until the end of the experiment, whereas others were outcompeted by parental strains. Genomic analysis of detected recombinants suggests host immune pressure as a major driver of recombinant emergence as all recombinants had capsid-coding regions derived from the superinfecting virus to which the animals did not have detectable antibodies at the time of infection. In vitro analysis of a plaque-purified recombinant virus demonstrated a growth rate comparable to its parental precursors, and measurement of its specific infectivity suggested that the recombinant virus incurred no penalty in packaging its new chimeric genome. These findings have important implications for the potential role of persistently infected carriers in FMDV ecology and the emergence of novel strains.

Phylogenetic analyses of foot-and-mouth disease type A viruses in the Middle East during 2015–2016 identified viruses belonging to the A/ASIA/G-VII lineage, which originated in the Indian subcontinent. Changes in a critical antigenic site within capsid viral protein 1 suggest possible evolutionary pressure caused by an intensive vaccination program.

Objective: Molecular based study was conducted to determine the associated serotypes in the reemergence of Foot and Mouth Disease (FMD) outbreak in Assiut governorate, Egypt during 2014 and 2015. Materials and methods: One hundred and twenty cattle with clinical signs suggesting their infection by FMDV were examined clinically and twenty three of them were used for confirmation by laboratory diagnosis. Different clinical samples including vesicular fluid and tongue epitheliums were collected and after RNA extraction using commercial kit, RT-PCR was done using different primer sets. Results: Serotype O was detected in 8 samples, 2 of them were also positive for SAT2 serotype. The determination of specific serotype was failed in case of the rest 13 samples although they were positive when tested by the universal primer specific for FMDV. Conclusion: Serotypes O and SAT2 were the more prevalent serotypes in the current outbreak in Assiut governorate, Egypt. [J Adv Vet Anim Res 2017; 4(1.000): 32-38]

Abstract: The objective of this work was to apply fuzzy majority multicriteria group decision-making to determine risk areas for foot-and-mouth disease (FMD) introduction along the border between Brazil and Paraguay. The study was conducted in three municipalities in the state of Mato Grosso do Sul, Brazil, located along the border with Paraguay. Four scenarios were built, applying the following linguistic quantifiers to describe risk factors: few, half, many, and most. The three criteria considered to be most likely to affect the vulnerability to introduction of FMD, according to experts' opinions, were: the introduction of animals in the farm, the distance from the border, and the type of property settlements. The resulting maps show a strong spatial heterogeneity in the risk of FMD introduction. The used methodology brings out a new approach that can be helpful to policy makers in the combat and eradication of FMD.

Foot-and-mouth disease virus (FMDV) infects hosts as a population of closely related viruses referred to as a quasispecies. The behavior of this quasispecies has not been described in detail in natural host species. In this study, virus samples collected from vaccinated and non-vaccinated cattle up to 35 days post-experimental infection with FMDV A24-Cruzeiro were analyzed by deep-sequencing. Vaccination induced significant differences compared to viruses from non-vaccinated cattle in substitution rates, entropy, and evidence for adaptation. Genomic variation detected during early infection reflected the diversity inherited from the source virus (inoculum), whereas by 12 days post infection, dominant viruses were defined by newly acquired mutations. Mutations conferring recognized fitness gain occurred and were associated with selective sweeps. Persistent infections always included multiple FMDV subpopulations, suggesting distinct foci of infection within the nasopharyngeal mucosa. Subclinical infection in vaccinated cattle included very early bottlenecks associated with reduced diversity within virus populations. Viruses from both animal cohorts contained putative antigenic escape mutations. However, these mutations occurred during later stages of infection, at which time transmission is less likely to occur. This study improves upon previously published work by analyzing deep sequences of samples, allowing for detailed characterization of FMDV populations over time within multiple hosts.

Foot-and-mouth-disease (FMD) is a highly contagious disease of domestic animals which can result in substantial economic losses, caused by the FMD virus (FMDV). The aim of this study was to develop and standardize a novel reverse transcriptase droplet digital PCR (RT-ddPCR) assay for the quantification of FMDV RNA. This assay was based upon an OIE-recognized real-time RT-PCR that detects the 3D-encoding region of FMDV. The limit of detection at 10 1.4 TCID 50 /mL and 26.5 copies was determined using FMDV-A24-Cruzeiro-virus and a plasmid containing the 3D-FMDV sequences, respectively. FMDV O, A and C serotypes and 11 species of non-FMDV were used to confirm the sensitivity and specificity of the assay. The RT-ddPCR was standardized using 60 bovine samples (representing negative and positive samples of epithelium and/or oesophageal-pharyngeal [OP] fluid) from animals suspected of vesicular diseases and previously tested by RT-qPCR. The RT-ddPCR showed robustness, sensitivity, specificity and accuracy, with similar results to the RT-qPCR. Moreover, the new RT-ddPCR diagnostic tool allowed the absolute quantification of FMDV RNA from epithelium and OP-fluid samples, as well as having the advantages of direct quantification by endpoint, eliminating the need for a calibration standard curve required in quantitative real-time RT-PCR. [ABSTRACT FROM AUTHOR]

Phylogenetic analyses of foot-and-mouth disease type A viruses in the Middle East during 2015-2016 identified viruses belonging to the A/ASIA/G-VII lineage, which originated in the Indian subcontinent. Changes in a critical antigenic site within capsid viral protein 1 suggest possible evolutionary pressure caused by an intensive vaccination program. [ABSTRACT FROM AUTHOR]

After a 16-year interval, foot-and-mouth disease virus serotype SAT 3 was isolated in 2013 from an apparently healthy long-horned Ankole calf that grazed close to buffalo in Uganda. The emergent virus strain is ≈20% different in nucleotide sequence (encoding VP1 [viral protein 1]) from its closest relatives isolated previously from buffalo in Uganda.

Objective: Molecular based study was conducted to determine the associated serotypes in the reemergence of Foot and Mouth Disease (FMD) outbreak in Assiut governorate, Egypt during 2014 and 2015. Materials and methods: One hundred and twenty cattle with clinical signs suggesting their infection by FMDV were examined clinically and twenty three of them were used for confirmation by laboratory diagnosis. Different clinical samples including vesicular fluid and tongue epitheliums were collected and after RNA extraction using commercial kit, RT-PCR was done using different primer sets. Results: Serotype O was detected in 8 samples, 2 of them were also positive for SAT2 serotype. The determination of specific serotype was failed in case of the rest 13 samples although they were positive when tested by the universal primer specific for FMDV. Conclusion: Serotypes O and SAT2 were the more prevalent serotypes in the current outbreak in Assiut governorate, Egypt. [ABSTRACT FROM AUTHOR]

We investigated the molecular epidemiology of foot-and-mouth disease virus (FMDV) serotype Asia 1, which caused outbreaks of disease in Asia during 2003–2007. Since 2004, the region affected by outbreaks of this serotype has increased from disease-endemic countries in southern Asia (Afghanistan, India, Iran, Nepal, Pakistan) northward to encompass Kyrgyzstan, Tajikistan, Uzbekistan, several regions of the People’s Republic of China, Mongolia, Eastern Russia, and North Korea. Phylogenetic analysis of complete virus capsid protein 1 (VP1) gene sequences demonstrated that the FMDV isolates responsible for these outbreaks belonged to 6 groups within the Asia 1 serotype. Some contemporary strains were genetically closely related to isolates collected historically from the region as far back as 25 years ago. Our analyses also indicated that some viruses have spread large distances between countries in Asia within a short time.

We describe the characterization of a foot-and-mouth disease (FMD) serotype A virus responsible for recent outbreaks of disease in Egypt. Phylogenetic analysis of VP1 nucleotide sequences demonstrated a close relationship to recent FMD virus isolates from East Africa, rather than to viruses currently circulating in the Middle East.

Foot-and-mouth disease viruses are often restricted to specific geographical regions and spread to new areas may lead to significant epidemics. Phylogenetic analysis of sequences of the VP1 genome region of recent outbreak viruses from Libya and Saudi Arabia has revealed a lineage, O-Ind-2001, normally found in the Indian subcontinent. This paper describes the characterization of field viruses collected from these cases and provides information about a new real-time RT- PCR assay that can be used to detect viruses from this lineage and discriminate them from other endemic FMD viruses that are co-circulating in North Africa and western Eurasia. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease is a frequently occurring disease of cloven-hoofed animals that is caused by infection with the foot-and-mouth virus (FMDV). FMDV circumvents the type-I IFN response by expressing proteins that antagonize cellular innate immunity, such as leader protease and 3C protease. We identified the FMDV structural protein VP3 as a negative regulator of the virus-triggered IFN-β signaling pathway. Expression of FMDV VP3 inhibited the Sendai virus-triggered activation of IFN regulatory factor-3 and the expression of retinoic acid-inducible gene-I/melanoma differentiation-associated protein-5. Transient transfection and coimmunoprecipitation confirmed that the structural protein VP3 interacts with virus-induced signaling adapter (VISA), which is dependent on the C-terminal aa 111-220 of VP3. In addition, we found that FMDV VP3 inhibits the expression of VISA by disrupting its mRNA. Taken together, our findings reveal a novel strategy used by the structural VP3 protein of FMDV to evade host innate immunity. [ABSTRACT FROM AUTHOR]

A particular genetic lineage of foot-and-mouth disease virus (FMDV) serotype O, which we have named the PanAsia strain, was responsible for an explosive pandemic in Asia and extended to parts of Africa and Europe from 1998 to 2001. In 2000 and 2001, this virus strain caused outbreaks in the Republic of Korea, Japan, Russia, Mongolia, South Africa, the United Kingdom, Republic of Ireland, France, and the Netherlands, countries which last experienced FMD outbreaks decades before (ranging from 1934 for Korea to 1984 for the Netherlands). Although the virus has been controlled in all of these normally FMD-free or sporadically infected countries, it appears to be established throughout much of southern Asia, with geographically separated lineages evolving independently. A pandemic such as this is a rare phenomenon but demonstrates the ability of newly emerging FMDV strains to spread rapidly throughout a wide region and invade countries previously free from the disease.

Highlights: [•] BSL-2 aphthoviruses were explored as surrogates for FMDV antiviral research. [•] Robust antiviral assays were developed for the surrogate viruses. [•] Surrogate models were validated by reference compounds and a novel FMDV inhibitor. [ABSTRACT FROM AUTHOR]

Abstract: Of the many members that comprise the family Picornaviridae, only two species are known to infect horses: equine rhinitis A virus (ERAV) and equine rhinitis B virus (ERBV). Each species now occupies a distinct phylogenetic branch within the family, with the single serotype of ERAV grouping with the aphthoviruses, such as foot-and-mouth disease virus (FMDV), and the three serotypes of ERBV as the sole members of the genus Erbovirus. The high seroprevalence of equine picornaviruses in horse populations worldwide contrasts with the relatively few reports of detection of these viruses and poor understanding of their contribution to disease. This review examines the current knowledge regarding the distribution and pathogenesis of these viruses and discusses recent advances in diagnostic methods that may lead to a better understanding of the role of these viruses as contributors to equine respiratory disease. [Copyright &y& Elsevier]

An outbreak of foot-and-mouth disease caused by serotype O virus occurred in cattle and pigs in South Korea during November 2010-April 2011. The highest rates of case and virus detection were observed 44 days after the first case was detected. Detection rates declined rapidly after culling and completion of a national vaccination program. [ABSTRACT FROM AUTHOR]

Abstract: Equine rhinitis A virus (ERAV) is a member of the Aphthovirus genus, and has many physical and structural similarities to the prototype Aphthovirus foot-and-mouth disease virus (FMDV). The pathogenesis of FMDV has been extensively studied, however, the similarities in the pathogenesis of ERAV and FMDV disease has not been well documented. This study describes and compares the pathogenesis of ERAV both in the natural host and a small animal model alternative (CBA mice). Distinct parallels in the pathogenesis of the acute infection of these two viruses are described where infection in the upper respiratory tract precedes shedding of high levels of virus from the nasopharynx and a transient viraemic phase before dissemination to distal sites. The finding that ERAV is maintained at high levels in the urine of infected horses for at least 37 days post infection, however, is a feature unique to ERAV amongst all of the picornaviruses. [Copyright &y& Elsevier]

Bovine Rhinitis B Virus (BRBV) is a picornavirus responsible for mild respiratory infection of cattle. It is probably the least characterized among the aphthoviruses. BRBV is the closest relative known to Foot and Mouth Disease virus (FMDV) with a ∼43% identical polyprotein sequence and as much as 67% identical sequence for the RNA dependent RNA polymerase (RdRp), which is also known as 3D polymerase (3Dpol). In the present study we carried out phylogenetic analysis, structure based sequence alignment and prediction of three-dimensional structure of BRBV 3Dpol using a combination of different computational tools. Model structures of BRBV 3Dpol were verified for their stereochemical quality and accuracy. The BRBV 3Dpol structure predicted by SWISS-MODEL exhibited highest scores in terms of stereochemical quality and accuracy, which were in the range of 2Å resolution crystal structures. The active site, nucleic acid binding site and overall structure were observed to be in agreement with the crystal structure of unliganded as well as template/primer (T/P), nucleotide tri-phosphate (NTP) and pyrophosphate (PPi) bound FMDV 3Dpol (PDB, 1U09 and 2E9Z). The closest proximity of BRBV and FMDV 3Dpol as compared to human rhinovirus type 16 (HRV-16) and rabbit hemorrhagic disease virus (RHDV) 3Dpols is also substantiated by phylogeny analysis and root-mean square deviation (RMSD) between C-α traces of the polymerase structures. The absence of positively charged α-helix at C terminal, significant differences in non-covalent interactions especially salt bridges and CH-pi interactions around T/P channel of BRBV 3Dpol compared to FMDV 3Dpol, indicate that despite a very high homology to FMDV 3Dpol, BRBV 3Dpol may adopt a different mechanism for handling its substrates and adapting to physiological requirements. Our findings will be valuable in the design of structure-function interventions and identification of molecular targets for drug design applicable to Aphthovirus RdRps. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to determine the incidence of serum neutralising (SN) antibody to ERAV, ERBV1 and ERBV2 in a population of horses from birth to 22 years of age. The prevalences of ERAV, ERBV1 and ERBV2 SN antibodies in 381 sera obtained from 291 horses were 37%, 83% and 66%, respectively. ERAV, ERBV1 and ERBV2 maternal antibody was present in foals 12h postsuckling but by 10–12 months, ERAV SN antibody was not detected in any of the horses, while ERBV1 and ERBV2 SN antibodies were common (83% and 100%, respectively). Sera were obtained from 44 Thoroughbred horses when they were newly introduced into a training centre when their average age was 23 months and a second sample was obtained ∼7 months later. ERAV SN antibody was present in 8 (18%) when first bled and in 27 (61%) when tested 7 months later. Accordingly 19 of the 44 horses (43%) seroconverted to ERAV within 7 months of entering the training stable. Among all the horses the average ERAV SN antibody titre was relatively high (3796) and in contrast, ERBV1 and ERBV2 titres were relatively low (average 84 and 45, respectively) and often fell to below detectable levels over time and at a rate comparable to new seroconversions in the same group of horses. [Copyright &y& Elsevier]

The present study was designed to evaluate serum biochemical and haematological parameters and serum nitrate concentrations in cattle suffering from foot- and -mouth disease (FMD). For this purpose, 30 Swiss Brown cattle aged between 3 and 5 years were used. Twenty cattle showed characteristic clinical signs of FMD, whereas the remaining 10 were clinically healthy and used as controls. Peripheral blood samples were collected from both groups and used to establish total white blood cells (WBCs), red blood cells (RBCs), haemoglobin (Hb), and haematocrit (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC) and mean corpuscular haemoglobin (MCH). Serum samples were also collected from these animals and used to establish the concentrations of total protein, albumin, urea nitrogen, creatinin, glucose, calcium, phosphorus, nitrate (NO3) and cholesterol and activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (AP). There was a significant decrease in the total number of RBCs (P < 0.05) and a significant increase in MCV (P < 0.05) in cattle with FMD compared to the control group. There were no significant differences in the other haematological parameters evaluated. Serum glucose concentration was significantly higher (P < 0.001) in the FMD group than in the control group. Serum total protein (P < 0.05), calcium (P < 0.01), albumin (P < 0.001) and cholesterol (P < 0.01) levels were significantly low in the FMD group compared to those in the control group. However, there were no significant differences in the other biochemical parameters between the groups. The concentration of serum NO3 was significantly high in the FMD group, suggesting that Aphtovirus induces the production of nitric oxide in vivo. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease virus (FMDV) infects hosts as a population of closely related viruses referred to as a quasispecies. The behavior of this quasispecies has not been described in detail in natural host species. In this study, virus samples collected from vaccinated and non-vaccinated cattle up to 35 days post-experimental infection with FMDV A24-Cruzeiro were analyzed by deep-sequencing. Vaccination induced significant differences compared to viruses from non-vaccinated cattle in substitution rates, entropy, and evidence for adaptation. Genomic variation detected during early infection reflected the diversity inherited from the source virus (inoculum), whereas by 12 days post infection, dominant viruses were defined by newly acquired mutations. Mutations conferring recognized fitness gain occurred and were associated with selective sweeps. Persistent infections always included multiple FMDV subpopulations, suggesting distinct foci of infection within the nasopharyngeal mucosa. Subclinical infection in vaccinated cattle included very early bottlenecks associated with reduced diversity within virus populations. Viruses from both animal cohorts contained putative antigenic escape mutations. However, these mutations occurred during later stages of infection, at which time transmission is less likely to occur. This study improves upon previously published work by analyzing deep sequences of samples, allowing for detailed characterization of FMDV populations over time within multiple hosts. [ABSTRACT FROM AUTHOR]

The foot-and-mouth disease virus (FMDV) genome contains a 5′ untranslated region (S fragment) capable of forming a stem-loop structure of over 350 bases, which is separated from the remainder of the genome by a homopolymeric cytidylic acid tract (poly(C)) of variable length. The sequence of the S fragment of serotype A appears more similar to those of type O or type C than to subtype A. The relatively large difference between the S fragment sequences of two type A viruses suggests that the sequences per se of this region of the genome are not critical for the maintenance of function, and suggests the possibility of a relatively recent recombination event within the poly(C) region of the A genome. [ABSTRACT FROM AUTHOR]