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Timothy B. Crawford - One of the best experts on this subject based on the ideXlab platform.
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intra nasal inoculation of american bison bison bison with ovine herpesvirus 2 ovhv 2 reliably reproduces Malignant Catarrhal Fever
Veterinary Pathology, 2007Co-Authors: Donal Otoole, Naomi S Taus, D L Montgomery, J L Oaks, Timothy B. CrawfordAbstract:Sheep-associated Malignant Catarrhal Fever (MCF) due to infection with ovine herpesvirus 2 (OvHV-2) is common in commercial herds of American bison (Bison bison). Inability to propagate OvHV-2 in vitro has been a constraint on experimental studies of the disease. We sought to establish whether nasal secretions from sheep that shed OvHV-2 might induce the disease in bison and to define a minimum challenge dose. Fourteen bison were nebulized with sheep nasal sections containing 103–107 OvHV-2 deoxyribonucleic acid (DNA) copies. Most challenged bison (11/14, 78.6%) developed clinical signs at 29–52 days postnebulization (DPN). The mean incubation time was 42.18 (±7.33 SD) DPN. Using real-time polymerase chain reaction, we detected OvHV-2 DNA in peripheral blood leukocytes at 21–31 DPN. All bison that developed MCF had antibodies against the MCF group viruses. Gross and histologic lesions were typical of the acute disease. There was no morphologic evidence of a dose-related difference in the severity or distr...
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a devastating outbreak of Malignant Catarrhal Fever in a bison feedlot
Journal of Veterinary Diagnostic Investigation, 2006Co-Authors: Naomi S Taus, Cevin Jones, Brian G Murphy, James F Evermann, Timothy B. CrawfordAbstract:In early 2003, an outbreak of Malignant Catarrhal Fever (MCF) occurred in a bison feedlot in southern Idaho. The outbreak resulted in a 51.2% (n = 825) mortality rate among bison, which had been exposed to sheep for 19 days. Diagnosis was made by detection of ovine herpesvirus 2 (sheep-associated MCF virus) DNA in tissues or peripheral blood by polymerase chain reaction (PCR), and by histological examination of tissue lesions. Peak losses occurred between 41 and 55 days postmean exposure time (PME), and reached a maximum of 41 head per day. No known cases of MCF were observed among the 177 head of bison that arrived in the lot 3 1/2 weeks after the departure of the sheep. Of the several thousand head of beef cattle in the lot during the outbreak, only a single case of MCF was identified. This outbreak illustrates the devastating impact the MCF virus can have on bison under certain exposure conditions, the high threat posed by adolescent lambs to susceptible species, the significantly greater susceptibility of bison than beef cattle to MCF, and the lack of horizontal transmission from clinically affected bison to herdmates.
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Malignant Catarrhal Fever like disease in sheep after intranasal inoculation with ovine herpesvirus 2
Journal of Veterinary Diagnostic Investigation, 2005Co-Authors: Hong Li, Lindsay J Oaks, Donal Otoole, Timothy B. CrawfordAbstract:A Malignant Catarrhal Fever (MCF)–like disease was induced experimentally in 3 sheep after aerosol inoculation with ovine herpesvirus-2 (OvHV-2). Each of 3 OvHV-2–negative sheep was nebulized with 2 ml of nasal secretions containing approximately 3.07 − 109 OvHV-2 DNA copies from a sheep experiencing an intensive viral-shedding episode. Ovine herpesvirus-2 DNA became detectable by polymerase chain reaction in the peripheral blood leukocytes of all 3 sheep within 3 days, and all 3 seroconverted between 6 and 8 days postinfection (PI). The sheep developed clinical signs, with copious mucopurulent nasal discharge and Fever around 14 days PI. One of the 3 clinically affected sheep was euthanized at 18 days PI. Major lesions at necropsy were multifocal linear erosions and ulcers in mucosa of the cheeks, tongue, pharynx, and proximal esophagus and mild disseminated pneumonia. Microscopically, there was extensive moderate superficial histiocytic–lymphocytic rhinitis with epithelial dissociation and degeneration....
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Evidence of three new members of Malignant Catarrhal Fever virus group in muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (Oryx gazella).
Journal of Wildlife Diseases, 2003Co-Authors: Hong Li, Keith West, Katherine L. Gailbreath, Janice Keller, Louis C Bender, Timothy B. CrawfordAbstract:Six members of the Malignant Catarrhal Fever (MCF) virus group of ruminant rhadinoviruses have been identified to date. Four of these viruses are clearly associated with clinical disease: alcelaphine herpesvirus 1 (AlHV-1) carried by wildebeest (Connochaetes spp.); ovine herpesvirus 2 (OvHV-2), ubiquitous in domestic sheep; caprine herpesvirus 2 (CpHV-2), endemic in domestic goats; and the virus of unknown origin found causing classic MCF in white-tailed deer (Odocoileus virginianus; MCFV-WTD). Using serology and polymerase chain reaction with degenerate primers targeting a portion of the herpesviral DNA polymerase gene, evidence of three previously unrecognized rhadinoviruses in the MCF virus group was found in muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (South African oryx, Oryx gazella), respectively. Based on sequence alignment, the viral sequence in the muskox is most closely related to MCFV-WTD (81.5% sequence identity) and that in the Nubian ibex is closest to CpHV-2 (89.3% ...
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caprine herpesvirus 2 associated Malignant Catarrhal Fever in white tailed deer odocoileus virginianus
Journal of Veterinary Diagnostic Investigation, 2003Co-Authors: Arno Wunschmann, Janice Keller, Greg D Hall, Timothy B. CrawfordAbstract:A subacute disease presenting primarily as alopecia and weight loss occurred in 2 white-tailed deer (Odocoileus virginianus) on farms in Minnesota and in Texas. A presumptive diagnosis of Malignant Catarrhal Fever (MCF) was made on the basis of histological lesions. Antibody against an epitope conserved among the MCF group viruses was detected in the serum of both deer. DNA samples from the deer were subjected to a variety of PCR amplifications. Alignment of the amplified sequences from the diseased animals revealed that they were 100% identical to each other and to the same DNA fragment from the newly recognized member of the MCF virus group endemic in domestic goats (Capra hircus), provisionally named caprine herpesvirus 2 (CpHV-2). A seroprevalence survey from one of the deer farms showed a high rate of subclincal infection in the deer population. This study provides further confirmation that CpHV-2 is a pathogen, at least for deer, and emphasizes the risk of loss from MCF when mixing cervids with goats.
Hong Li - One of the best experts on this subject based on the ideXlab platform.
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a rabbit model for sheep associated Malignant Catarrhal Fever research from virus infection to pathogenesis studies and vaccine development
Current Clinical Microbiology Reports, 2019Co-Authors: Cristina W Cunha, Naomi S Taus, Donald P Knowles, Donal Otoole, Smriti Shringi, Hong LiAbstract:Purpose of Review Describe the implementation and use of rabbits as a laboratory model for sheep-associated Malignant Catarrhal Fever (SA-MCF) research using cell-free ovine herpesvirus 2 (OvHV-2). Key considerations regarding the use of the model to generate consistent experimental data are presented and discussed in detail.
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Seroprevalence of Malignant Catarrhal Fever virus in captive wildebeest (Connochaetes sp.) in France
Transboundary and Emerging Diseases, 2018Co-Authors: Katia Ortiz, Francoise Myster, Justine Javaux, Marie Simon, Sylvie Clavel, Barbara Blanc, Alice Brunet, Thierry Petit, Benjamin Lamglait, Hong LiAbstract:Alcelaphine herpesvirus 1 (AlHV-1) is a gammaherpesvirus carried asymptomatically by wildebeests (Connochaetes sp.) in sub-Saharan Africa. Although asymptomatic in wildebeest, AlHV-1 infection in a number of other ruminant species causes a severe and fatal lymphoproliferative disease named wildebeest-derived Malignant Catarrhal Fever (WD-MCF). Several endangered species of captive ruminants are highly susceptible to developing WD-MCF if infected by AlHV-1, which is a critical concern in zoos, game reserves and wildlife parks where wildebeests are also kept in captivity. Here, we investigated the seroprevalence of AlHV-1 in 52 captive wildebeests randomly sampled from five different zoos in France. We found 46% (24/52) seropositive animals and detected AlHV-1 DNA in one of them, demonstrating that AlHV-1 infection is present in captive wildebeests in France. In an interesting manner, the repartition of seropositive wildebeests was not homogenous between zoos with 100% (20/20) of seronegative animals in three parks. These results further highlight the importance of considering WD-MCF as a threat for clinically susceptible species and encourage for testing AlHV-1 infection in captive wildebeests as a management control strategy.
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sheep associated Malignant Catarrhal Fever like skin disease in a free ranging bighorn sheep ovis canadensis alberta canada
Journal of Wildlife Diseases, 2017Co-Authors: Owen M Slater, Hong Li, Jeanine Peterskennedy, Manigandan Lejeune, David L Gummer, Bryan J Macbeth, Amy L Warren, Tomy JosephAbstract:Abstract Malignant Catarrhal Fever–like clinical disease was diagnosed in a free-ranging bighorn sheep (Ovis canadensis) from Alberta, Canada, in June 2015. Antemortem and gross pathology findings included muscle atrophy, marked weight loss, and bilaterally symmetric alopecia with hyperpigmentation and crusting over the face, medial surfaces of the pinnae, dorsal trunk, distal limbs, perineal area, and tail. Histologically, the skin lesions were characterized by granulomatous mural folliculitis with numerous multinucleated giant cells and fewer lymphocytes and eosinophils consistent with previous reports of chronic ovine herpesvirus-2 (OvHV-2) infection. Multiple skin samples were positive for OvHV-2 DNA on PCR, and on partial sequencing of the viral DNA, there was 94% homology with reference GenBank OvHV-2. Quantitative PCR confirmed an increased level of OvHV-2 DNA in the lesional skin tissues. Based on exclusion of other disease processes, gross and histological lesions, PCR, and viral DNA sequencing r...
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replacement of glycoprotein b in alcelaphine herpesvirus 1 by its ovine herpesvirus 2 homolog implications in vaccine development for sheep associated Malignant Catarrhal Fever
mSphere, 2016Co-Authors: Cristina W Cunha, Alain Vanderplasschen, Benjamin G Dewals, Naomi S Taus, Hong Li, Donald P KnowlesAbstract:ABSTRACT Vaccine development is a top priority in Malignant Catarrhal Fever (MCF) research. In the case of sheep-associated MCF (SA-MCF) caused by ovine herpesvirus 2 (OvHV-2), progress toward this objective has been hindered by the absence of methods to attenuate or modify the virus, since it cannot be propagated in vitro. As an alternative for vaccine development, in this study, we tested the hypothesis that one of the SA-MCF vaccine candidate targets, OvHV-2 glycoprotein B (gB), could be expressed by a nonpathogenic alcelaphine herpesvirus 1 (AlHV-1) and then evaluated the potential of the AlHV-1/OvHV-2 chimera to be used as a vaccine and a diagnostic tool. The construction and characterization of an AlHV-1/OvHV-2 chimeric virus that is nonpathogenic and expresses an OvHV-2 vaccine target are significant steps toward the development of an SA-MCF vaccine and also provide a valuable means to study OvHV-2 biology.
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Cross-Reactivity of Neutralizing Antibodies among Malignant Catarrhal Fever Viruses.
PLOS ONE, 2015Co-Authors: Naomi S Taus, Cristina W Cunha, Jana Marquard, Donal O’toole, Hong LiAbstract:Some members of the gamma herpesvirus genus Macavirus are maintained in nature as subclinical infections in well-adapted ungulate hosts. Transmission of these viruses to poorly adapted hosts, such as American bison and cattle, can result in the frequently fatal disease Malignant Catarrhal Fever (MCF). Based on phylogenetic analysis, the MCF viruses (MCFV) cluster into two subgroups corresponding to the reservoir hosts’ subfamilies: Alcelaphinae/Hippotraginae and Caprinae. Antibody cross-reactivity among MCFVs has been demonstrated using techniques such as enzyme linked immunosorbent and immunofluorescence assays. However, minimal information is available as to whether virus neutralizing antibodies generated against one MCFV cross react with other members of the genus. This study tested the neutralizing activity of serum and plasma from select MCFV-infected reservoir hosts against alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2). Neutralizing antibody activity against AlHV-1 was detected in samples from infected hosts in the Alcelaphinae and Hippotraginae subfamilies, but not from hosts in the Caprinae subfamily. OvHV-2 neutralizing activity was demonstrated in samples from goats (Caprinae) but not from wildebeest (Alcelaphinae). These results show that neutralizing antibody cross reactivity is present to MCFVs within a virus subgroup but not between subgroups. This information is important for diagnosing infection with MCFVs and in the development of vaccines against MCF.
Naomi S Taus - One of the best experts on this subject based on the ideXlab platform.
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a rabbit model for sheep associated Malignant Catarrhal Fever research from virus infection to pathogenesis studies and vaccine development
Current Clinical Microbiology Reports, 2019Co-Authors: Cristina W Cunha, Naomi S Taus, Donald P Knowles, Donal Otoole, Smriti Shringi, Hong LiAbstract:Purpose of Review Describe the implementation and use of rabbits as a laboratory model for sheep-associated Malignant Catarrhal Fever (SA-MCF) research using cell-free ovine herpesvirus 2 (OvHV-2). Key considerations regarding the use of the model to generate consistent experimental data are presented and discussed in detail.
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replacement of glycoprotein b in alcelaphine herpesvirus 1 by its ovine herpesvirus 2 homolog implications in vaccine development for sheep associated Malignant Catarrhal Fever
mSphere, 2016Co-Authors: Cristina W Cunha, Alain Vanderplasschen, Benjamin G Dewals, Naomi S Taus, Hong Li, Donald P KnowlesAbstract:ABSTRACT Vaccine development is a top priority in Malignant Catarrhal Fever (MCF) research. In the case of sheep-associated MCF (SA-MCF) caused by ovine herpesvirus 2 (OvHV-2), progress toward this objective has been hindered by the absence of methods to attenuate or modify the virus, since it cannot be propagated in vitro. As an alternative for vaccine development, in this study, we tested the hypothesis that one of the SA-MCF vaccine candidate targets, OvHV-2 glycoprotein B (gB), could be expressed by a nonpathogenic alcelaphine herpesvirus 1 (AlHV-1) and then evaluated the potential of the AlHV-1/OvHV-2 chimera to be used as a vaccine and a diagnostic tool. The construction and characterization of an AlHV-1/OvHV-2 chimeric virus that is nonpathogenic and expresses an OvHV-2 vaccine target are significant steps toward the development of an SA-MCF vaccine and also provide a valuable means to study OvHV-2 biology.
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RESEARCH ARTICLE Cross-Reactivity of Neutralizing Antibodies among Malignant Catarrhal Fever Viruses
2016Co-Authors: Naomi S Taus, Cristina W Cunha, Jana MarquardAbstract:Some members of the gamma herpesvirus genusMacavirus are maintained in nature as subclinical infections in well-adapted ungulate hosts. Transmission of these viruses to poorly adapted hosts, such as American bison and cattle, can result in the frequently fatal disease Malignant Catarrhal Fever (MCF). Based on phylogenetic analysis, the MCF viruses (MCFV) cluster into two subgroups corresponding to the reservoir hosts ’ subfamilies: Alce-laphinae/Hippotraginae and Caprinae. Antibody cross-reactivity among MCFVs has been demonstrated using techniques such as enzyme linked immunosorbent and immunofluo-rescence assays. However, minimal information is available as to whether virus neutralizing antibodies generated against one MCFV cross react with other members of the genus. This study tested the neutralizing activity of serum and plasma from select MCFV-infected reser-voir hosts against alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2). Neutralizing antibody activity against AlHV-1 was detected in samples from infected hosts in the Alcelaphinae and Hippotraginae subfamilies, but not from hosts in the Caprinae sub-family. OvHV-2 neutralizing activity was demonstrated in samples from goats (Caprinae) but not from wildebeest (Alcelaphinae). These results show that neutralizing antibody cross reactivity is present to MCFVs within a virus subgroup but not between subgroups. This information is important for diagnosing infection with MCFVs and in the development of vac-cines against MCF
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Cross-Reactivity of Neutralizing Antibodies among Malignant Catarrhal Fever Viruses.
PLOS ONE, 2015Co-Authors: Naomi S Taus, Cristina W Cunha, Jana Marquard, Donal O’toole, Hong LiAbstract:Some members of the gamma herpesvirus genus Macavirus are maintained in nature as subclinical infections in well-adapted ungulate hosts. Transmission of these viruses to poorly adapted hosts, such as American bison and cattle, can result in the frequently fatal disease Malignant Catarrhal Fever (MCF). Based on phylogenetic analysis, the MCF viruses (MCFV) cluster into two subgroups corresponding to the reservoir hosts’ subfamilies: Alcelaphinae/Hippotraginae and Caprinae. Antibody cross-reactivity among MCFVs has been demonstrated using techniques such as enzyme linked immunosorbent and immunofluorescence assays. However, minimal information is available as to whether virus neutralizing antibodies generated against one MCFV cross react with other members of the genus. This study tested the neutralizing activity of serum and plasma from select MCFV-infected reservoir hosts against alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2). Neutralizing antibody activity against AlHV-1 was detected in samples from infected hosts in the Alcelaphinae and Hippotraginae subfamilies, but not from hosts in the Caprinae subfamily. OvHV-2 neutralizing activity was demonstrated in samples from goats (Caprinae) but not from wildebeest (Alcelaphinae). These results show that neutralizing antibody cross reactivity is present to MCFVs within a virus subgroup but not between subgroups. This information is important for diagnosing infection with MCFVs and in the development of vaccines against MCF.
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Malignant Catarrhal Fever in american bison bison bison experimentally infected with alcelaphine herpesvirus 2
Veterinary Microbiology, 2014Co-Authors: Naomi S Taus, Cristina W Cunha, Donal Otoole, David R Herndon, Janet V Warg, Bruce S Seal, Angela BrookingAbstract:Abstract Malignant Catarrhal Fever (MCF), due to ovine herpesvirus 2 (OvHV-2), causes appreciable death loss in ranched bison ( Bison bison ) throughout North America. No vaccine exists to protect animals from disease. Since OvHV-2 has not been propagated in vitro , one strategy to develop a modified live vaccine is to use a closely related, non-pathogenic member of the Malignant Catarrhal Fever virus family as a vector expressing potentially protective OvHV-2 epitopes. To date, no controlled experimental challenge studies with alcelaphine herpesvirus 2 (AlHV-2) derived from topi ( Damaliscus lunatus jimela ) have been reported The unique or light DNA segment of the AlHV-2 genome was sequenced and annotated and the virus was tested for its ability to infect and induce disease in American bison. Yearling bison were inoculated intranasally ( n = 4) or intramuscularly ( n = 3) with 2 × 10 −4.7 TCID 50 of AlHV-2, and monitored for infection and the development of disease. Six inoculated bison became infected with AlHV-2. Two of the six animals developed clinical signs and had gross and histological lesions consistent with terminal MCF, which differed in distribution from those in bison with MCF due to OvHV-2. One other animal developed minor clinical signs and had gross and histological pulmonary lesions consistent with early (pre-clinical) stages of MCF. Unmodified low cell culture passage AlHV-2 derived from topi is an unsuitable vaccine vector for the prevention of MCF. However, the annotated genome might be useful in identifying genes which could be deleted to potentially attenuate the virus for bison.
Felix Lankester - One of the best experts on this subject based on the ideXlab platform.
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A randomised vaccine field trial in Kenya demonstrates protection against wildebeest-associated Malignant Catarrhal Fever in cattle.
Vaccine, 2019Co-Authors: Elizabeth A. J. Cook, Dawn M. Grant, Christine N. Mutisya, Lazarus Omoto, Elizabeth Dobson, Felix Lankester, George C. Russell, Vishvanath NeneAbstract:Abstract Wildebeest-associated Malignant Catarrhal Fever (WA-MCF), a fatal disease of cattle caused by alcelaphine herpesvirus 1 (AlHV-1), is one of the most important seasonal diseases of cattle in wildebeest endemic areas, with annual incidence reaching 10%. Here we report efficacy of over 80% for a vaccine based on the attenuated AlHV-1 C500 strain, in preventing fatal WA-MCF in cattle exposed to natural wildebeest challenge. The study was conducted at Kapiti Plains Ranch Ltd, south-east of Nairobi, Kenya. In 2016, 146 cattle were selected for a randomised placebo-controlled trial. Cattle were stratified according to breed and age and randomly assigned to groups given vaccine or culture medium mixed with Emulsigen®. Cattle received prime and boost inoculations one month apart and few adverse reactions (n = 4) were observed. Indirect ELISA demonstrated that all cattle in the vaccine group developed a serological response to AlHV-1. The study herd was grazed with wildebeest from one month after booster vaccination. Three cattle, two that received vaccine and one control, succumbed to conditions unrelated to WA-MCF before the study ended. Twenty-five cattle succumbed to WA-MCF; four of the remaining 71 cattle in the vaccine group (5.6%) and 21 of the remaining 72 control cattle (29.2%; χ2 = 13.6, df = 1, p
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RESEARCH ARTICLE The Economic Impact of Malignant Catarrhal Fever on Pastoralist Livelihoods
2016Co-Authors: Felix Lankester, Ahmed Lugelo, Rudovick R. Kazwala, Julius Keyyu, Sarah Cleavel, Jonathan YoderAbstract:This study is the first to partially quantify the potential economic benefits that a vaccine, ef-fective at protecting cattle against Malignant Catarrhal Fever (MCF), could accrue to pasto-ralists living in East Africa. The benefits would result from the removal of household resource and management costs that are traditionally incurred avoiding the disease. MCF, a fatal disease of cattle caused by a virus transmitted from wildebeest calves, has plagued Maasai communities in East Africa for generations. The threat of the disease forces the Maasai to move cattle to less productive grazing areas to avoid wildebeest during calving season when forage quality is critical. To assess the management and resource costs asso-ciated with moving, we used household survey data. To estimate the costs associated with changes in livestock body condition that result from being herded away from wildebeest calving grounds, we exploited an ongoing MCF vaccine field trial and we used a hedonic price regression, a statistical model that allows estimation of the marginal contribution of a good’s attributes to its market price. We found that 90 percent of households move, on aver-age, 82 percent of all cattle away from home to avoid MCF. In doing so, a herd’s productiv
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A field vaccine trial in Tanzania demonstrates partial protection against Malignant Catarrhal Fever in cattle
Vaccine, 2015Co-Authors: Felix Lankester, Dawn M. Grant, Ahmed Lugelo, Nicholas Mnyambwa, Ahab Ndabigaye, George C. Russell, Rudovick R. Kazwala, Julius Keyyu, Ann Percival, David DeaneAbstract:Malignant Catarrhal Fever (MCF) is a fatal lymphoproliferative disease of cattle that, in East Africa, results from transmission of the causative virus, alcelaphine herpesvirus 1 (AlHV-1), from wildebeest. A vaccine field trial involving an attenuated AlHV-1 virus vaccine was performed over two wildebeest calving seasons on the Simanjiro Plain of northern Tanzania. Each of the two phases of the field trial consisted of groups of 50 vaccinated and unvaccinated cattle, which were subsequently exposed to AlHV-1 challenge by herding toward wildebeest. Vaccination resulted in the induction of virus-specific and virus-neutralizing antibodies. Some cattle in the unvaccinated groups also developed virus-specific antibody responses but only after the start of the challenge phase of the trial. PCR of DNA from blood samples detected AlHV-1 infection in both groups of cattle but the frequency of infection was significantly lower in the vaccinated groups. Some infected animals showed clinical signs suggestive of MCF but few animals went on to develop fatal MCF, with similar numbers in vaccinated and unvaccinated groups. This study demonstrated a baseline level of MCF-seropositivity among cattle in northern Tanzania of 1% and showed that AlHV-1 virus-neutralizing antibodies could be induced in Tanzanian zebu shorthorn cross cattle by our attenuated vaccine, a correlate of protection in previous experimental trials. The vaccine reduced infection rates by 56% in cattle exposed to wildebeest but protection from fatal MCF could not be determined due to the low number of fatal cases.
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alcelaphine herpesvirus 1 Malignant Catarrhal Fever virus in wildebeest placenta genetic variation of orf50 and a9 5 alleles
PLOS ONE, 2015Co-Authors: Dawn M. Grant, Ahmed Lugelo, Nicholas Mnyambwa, Ahab Ndabigaye, Valerie Relf, Felix Lankester, Rudovick R. Kazwala, Julius Keyyu, David M. HaigAbstract:Alcelaphine herpesvirus–1 (AlHV-1), a causative agent of Malignant Catarrhal Fever in cattle, was detected in wildebeest (Connochaetes taurinus) placenta tissue for the first time. Although viral load was low, the finding of viral DNA in over 50% of 94 samples tested lends support to the possibility that placental tissue could play a role in disease transmission and that wildebeest calves are infected in utero. Two viral loci were sequenced to examine variation among virus samples obtained from wildebeest and cattle: the ORF50 gene, encoding the lytic cycle transactivator protein, and the A9.5 gene, encoding a novel polymorphic viral glycoprotein. ORF50 was well conserved with six newly discovered alleles differing at only one or two base positions. In contrast, while only three new A9.5 alleles were discovered, these differed by up to 13% at the nucleotide level and up to 20% at the amino acid level. Structural homology searching performed with the additional A9.5 sequences determined in this study adds power to recent analysis identifying the four-helix bundle cytokine interleukin-4 (IL4) as the major homologue. The majority of MCF virus samples obtained from Tanzanian cattle and wildebeest encoded A9.5 polypeptides identical to the previously characterized A9.5 allele present in the laboratory maintained AlHV-1 C500 strain. This supports the view that AlHV-1 C500 is suitable for the development of a vaccine for wildebeest-associated MCF.
David M. Haig - One of the best experts on this subject based on the ideXlab platform.
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alcelaphine herpesvirus 1 Malignant Catarrhal Fever virus in wildebeest placenta genetic variation of orf50 and a9 5 alleles
PLOS ONE, 2015Co-Authors: Dawn M. Grant, Ahmed Lugelo, Nicholas Mnyambwa, Ahab Ndabigaye, Valerie Relf, Felix Lankester, Rudovick R. Kazwala, Julius Keyyu, David M. HaigAbstract:Alcelaphine herpesvirus–1 (AlHV-1), a causative agent of Malignant Catarrhal Fever in cattle, was detected in wildebeest (Connochaetes taurinus) placenta tissue for the first time. Although viral load was low, the finding of viral DNA in over 50% of 94 samples tested lends support to the possibility that placental tissue could play a role in disease transmission and that wildebeest calves are infected in utero. Two viral loci were sequenced to examine variation among virus samples obtained from wildebeest and cattle: the ORF50 gene, encoding the lytic cycle transactivator protein, and the A9.5 gene, encoding a novel polymorphic viral glycoprotein. ORF50 was well conserved with six newly discovered alleles differing at only one or two base positions. In contrast, while only three new A9.5 alleles were discovered, these differed by up to 13% at the nucleotide level and up to 20% at the amino acid level. Structural homology searching performed with the additional A9.5 sequences determined in this study adds power to recent analysis identifying the four-helix bundle cytokine interleukin-4 (IL4) as the major homologue. The majority of MCF virus samples obtained from Tanzanian cattle and wildebeest encoded A9.5 polypeptides identical to the previously characterized A9.5 allele present in the laboratory maintained AlHV-1 C500 strain. This supports the view that AlHV-1 C500 is suitable for the development of a vaccine for wildebeest-associated MCF.
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Duration of protective immunity and antibody responses in cattle immunised against alcelaphine herpesvirus-1-induced Malignant Catarrhal Fever
Veterinary Research, 2012Co-Authors: George C. Russell, Dawn Grant, Maira Connelly, Jackie Thomson, David Deane, Julio Benavides, Helen Todd, Ann Percival, David M. HaigAbstract:Protection of cattle from alcelaphine herpesvirus-1 (AlHV-1)-induced Malignant Catarrhal Fever (MCF) has been described previously, using an attenuated virus vaccine in an unlicensed adjuvant. The vaccine was hypothesised to induce a protective barrier of virus-neutralising antibody in the oro-nasal region, supported by the observation of high titre neutralising antibodies in nasal secretions of protected animals. Here we describe further analysis of this vaccine strategy, studying the effectiveness of the vaccine formulated with a licensed adjuvant; the duration of immunity induced; and the virus-specific antibody responses in plasma and nasal secretions. The results presented here show that the attenuated AlHV-1 vaccine in a licensed adjuvant protected cattle from fatal intranasal challenge with pathogenic AlHV-1 at three or six months. In addition, animals protected from MCF had significantly higher initial anti-viral antibody titres than animals that succumbed to disease; and these antibody titres remained relatively stable after challenge, while titres in vaccinated animals with MCF increased significantly prior to the onset of clinical disease. These data support the view that a mucosal barrier of neutralising antibody blocks infection of vaccinated animals and suggests that the magnitude of the initial response may correlate with long-term protection. Interestingly, the high titre virus-neutralising antibody responses seen in animals that succumbed to MCF after vaccination were not protective.
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an immunisation strategy for the protection of cattle against alcelaphine herpesvirus 1 induced Malignant Catarrhal Fever
Vaccine, 2008Co-Authors: David M. Haig, Dawn M. Grant, Jackie Thomson, Catherine Jepson, David Deane, David Buxton, I Campbell, George C. RussellAbstract:Abstract The aim of this study was to stimulate immunity in the oro-nasal-pharyngeal region of cattle to protect them from alcelaphine herpesvirus-1 (AlHV-1)-induced Malignant Catarrhal Fever. Attenuated C500 strain AlHV-1 was used along with Freund's adjuvant intramuscularly (IM) in the upper neck region to immunise cattle. Virulent C500 strain AlHV-1 was used for intranasal challenge. Nine of ten cattle were protected. Protection was associated with high levels of neutralising antibody in nasal secretions. Some protected animals showed transient low levels of viral DNA in blood samples and in one lymph node sample after challenge whereas viral DNA was detected in the blood and in lymph node samples of all animals with MCF. This is the most promising immunisation strategy to date for the control of Malignant Catarrhal Fever.