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Boshra H, Blyth GAD, Truong T, Kroeker A, Kara P, Mather A, Wallace D, Babiuk S. The Development of a Multivalent Capripoxvirus-Vectored Vaccine Candidate to Protect against Sheeppox, Goatpox, Peste des Petits Ruminants, and Rift Valley Fever. Vaccines (Basel) 2024; 12:805. [PMID: 39066443 PMCID: PMC11281512 DOI: 10.3390/vaccines12070805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/09/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
Capripoxviruses are the causative agents of sheeppox, goatpox, and lumpy skin disease (LSD) in cattle, which cause economic losses to the livestock industry in Africa and Asia. Capripoxviruses are currently controlled using several live attenuated vaccines. It was previously demonstrated that a lumpy skin disease virus (LSDV) field isolate from Warmbaths (WB) South Africa, ORF 005 (IL-10) gene-deleted virus (LSDV WB005KO), was able to protect sheep and goats against sheeppox and goatpox. Subsequently, genes encoding the protective antigens for peste des petits ruminants (PPR) and Rift Valley fever (RVF) viruses have been inserted in the LSDV WB005KO construct in three different antigen forms (native, secreted, and fusion). These three multivalent vaccine candidates were evaluated for protection against PPR using a single immunization of 104 TCID50 in sheep. The vaccine candidates with the native and secreted antigens protected sheep against PPR clinical disease and decreased viral shedding, as detected using real-time RT-PCR in oral and nasal swabs. An anamnestic antibody response, measured using PPR virus-neutralizing antibody response production, was observed in sheep following infection. The vaccine candidates with the antigens expressed in their native form were evaluated for protection against RVF using a single immunization with doses of 104 or 105 TCID50 in sheep and goats. Following RVF virus infection, sheep and goats were protected against clinical disease and no viremia was detected in serum compared to control animals, where viremia was detected one day following infection. Sheep and goats developed RVFV-neutralizing antibodies prior to infection, and the antibody responses increased following infection. These results demonstrate that an LSD virus-vectored vaccine candidate can be used in sheep and goats to protect against multiple viral infections.
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Affiliation(s)
- Hani Boshra
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB R3E 3M4, Canada; (H.B.); (T.T.); (A.K.)
- Department of Pathology, Fundamental and Applied Research for Animals and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, 4000 Liège, Belgium
| | - Graham A. D. Blyth
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB R3E 3M4, Canada; (H.B.); (T.T.); (A.K.)
| | - Thang Truong
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB R3E 3M4, Canada; (H.B.); (T.T.); (A.K.)
| | - Andrea Kroeker
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB R3E 3M4, Canada; (H.B.); (T.T.); (A.K.)
| | - Pravesh Kara
- ARC-Onderstepoort Veterinary Research, Onderstepoort, Pretoria 0110, South Africa; (P.K.); (A.M.)
| | - Arshad Mather
- ARC-Onderstepoort Veterinary Research, Onderstepoort, Pretoria 0110, South Africa; (P.K.); (A.M.)
| | - David Wallace
- ARC-Onderstepoort Veterinary Research, Onderstepoort, Pretoria 0110, South Africa; (P.K.); (A.M.)
| | - Shawn Babiuk
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB R3E 3M4, Canada; (H.B.); (T.T.); (A.K.)
- Department of Immunology, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0T5, Canada
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Shumilova I, Shalina K, Abed Alhussen M, Prutnikov P, Krotova A, Byadovskaya O, Prokhvatilova L, Chvala I, Sprygin A. An Attenuated Vaccine Virus of the Neethling Lineage Protects Cattle against the Virulent Recombinant Vaccine-like Isolate of the Lumpy Skin Disease Virus Belonging to the Currently Established Cluster 2.5. Vaccines (Basel) 2024; 12:598. [PMID: 38932327 PMCID: PMC11209201 DOI: 10.3390/vaccines12060598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/20/2024] [Accepted: 05/21/2024] [Indexed: 06/28/2024] Open
Abstract
Lumpy skin disease (LSD) is an emerging transboundary and highly infectious viral disease mainly affecting cattle. The fact that it was initially confined to Africa and then spread beyond its geographical range to other regions, including the Middle East, Turkey, Europe, the Balkans, Russia and Asia, is an indication of the underestimation and neglect of this disease. Vaccination is considered the most effective way to control the spread of LSDV, when combined with other control measures. LSD is now on the rise in Southeast Asia, where the circulating virus belongs to recombinant lineage 2.5. In this study, we evaluated the efficacy of an attenuated LSDV strain belonging to the Neethling cluster 1.1 by challenge with a virulent recombinant vaccine-like LSDV isolate "Mongolia/2021" belonging to cluster 2.5. Some of the vaccinated animals showed an increase in body temperature of 1-1.5 °C above the physiological norm, without clinical signs, local reactions, vaccine-induced viremia or generalization, demonstrating the efficacy and safety of the vaccine strain against a recombinant strain. Furthermore, all the vaccinated animals showed strong immune responses, indicating a high level of immunogenicity. However, the control group challenged with "Mongolia/2021" LSD showed moderate to severe clinical signs seen in an outbreak, with high levels of virus shedding in blood samples and nasal swabs. Overall, the results of the present study demonstrate that the attenuated LSDV Neethling strain vaccine has a promising protective phenotype against the circulating strains, suggesting its potential as an effective tool for the containment and control of LSD in affected countries from Southeast Asia.
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Yadav D, Rao GSNK, Paliwal D, Singh A, Alam A, Sharma PK, Surendra AV, Varshney P, Kumar Y. Cracking the Code of Lumpy Skin Disease: Identifying Causes, Symptoms and Treatment Options for Livestock Farmers. Infect Disord Drug Targets 2024; 24:e150124225632. [PMID: 38231058 DOI: 10.2174/0118715265261364231120053105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 10/04/2023] [Accepted: 10/12/2023] [Indexed: 01/18/2024]
Abstract
The novel bovine viral infection known as lumpy skin disease is common in most African and Middle Eastern countries, with a significant likelihood of disease transfer to Asia and Europe. Recent rapid disease spread in formerly disease-free zones highlights the need of understanding disease limits and distribution mechanisms. Capripox virus, the causal agent, may also cause sheeppox and Goatpox. Even though the virus is expelled through several bodily fluids and excretions, the most common causes of infection include sperm and skin sores. Thus, vulnerable hosts are mostly infected mechanically by hematophagous arthropods such as biting flies, mosquitoes, and ticks. As a result, milk production lowers, abortions, permanent or temporary sterility, hide damage, and mortality occur, contributing to a massive financial loss for countries that raise cattle. These illnesses are economically significant because they affect international trade. The spread of Capripox viruses appears to be spreading because to a lack of effectual vaccinations and poverty in rural areas. Lumpy skin disease has reached historic levels; as a consequence, vaccination remains the only viable option to keep the illness from spreading in endemic as well as newly impacted areas. This study is intended to offer a full update on existing knowledge of the disease's pathological characteristics, mechanisms of spread, transmission, control measures, and available vaccinations.
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Affiliation(s)
- Devdhar Yadav
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - G S N Koteswara Rao
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKM's NMIMS, V.L. Mehta Road, Vile Parle (W), Mumbai- 400056, India
| | - Deepika Paliwal
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Amit Singh
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Aftab Alam
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Pramod Kumar Sharma
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Amareswarapu V Surendra
- K L College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur, Andhra Pradesh, India
| | - Prachi Varshney
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Yogesh Kumar
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
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Ntombela N, Matsiela M, Zuma S, Hiralal S, Naicker L, Mokoena N, Khoza T. Production of recombinant lumpy skin disease virus A27L and L1R proteins for application in diagnostics and vaccine development. Vaccine X 2023; 15:100384. [PMID: 37736535 PMCID: PMC10509699 DOI: 10.1016/j.jvacx.2023.100384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/23/2023] Open
Abstract
Vaccination using live attenuated vaccines (LAVs) is considered the most effective method for control of lumpy skin disease (LSD). However, this method is limited by safety concerns, with reports of adverse reactions following vaccination. This study evaluates A27L and L1R which are essential proteins for virus attachment and membrane fusion as recombinant sub-unit vaccines against LSD. These proteins were recombinantly expressed in Escherichia coli and purified using affinity chromatography. Purified proteins were formulated individually (A27L or L1R) and in combination (A27L and L1R) with 10% (w/w) Montanide™ Gel 01 PR adjuvant at a final antigen dose of 20 µg per protein. The safety and immunogenicity of these formulations were evaluated in rabbits in a 42-day clinical trial. Animals were vaccinated on day 0 and boost injection administered 21 days later. No reduced morbidity, increased temperature and any other clinical signs were recorded in vaccinated animals for all three vaccine formulations. The highest neutralizing antibody response was detected on day 42 post-primary vaccination for all formulations when using serum neutralising assay. The neutralisation data correlates with antibody titres quantified using a whole cell ELISA. Evaluating the combination of A27L and L1R as potential diagnostic reagents showed highest sensitivity for detection of antibodies against LSD when compared to individual proteins. This study reports the immunogenicity of recombinant A27L and L1R combination for successful application in LSD vaccine development. Furthermore, these proteins demonstrated the potential use in LSD diagnostics.
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Affiliation(s)
- Nomfundo Ntombela
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville 3209, KwaZulu-Natal, South Africa
| | - Matome Matsiela
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville 3209, KwaZulu-Natal, South Africa
- Onderstepoort Biological Products (SOC. Ltd), 100, Old, Soutpan Road, Onderstepoort, 0110, Pretoria, South Africa
| | - Sbahle Zuma
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville 3209, KwaZulu-Natal, South Africa
| | - Suhavna Hiralal
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville 3209, KwaZulu-Natal, South Africa
| | - Leeann Naicker
- Onderstepoort Biological Products (SOC. Ltd), 100, Old, Soutpan Road, Onderstepoort, 0110, Pretoria, South Africa
| | - Nobalanda Mokoena
- Onderstepoort Biological Products (SOC. Ltd), 100, Old, Soutpan Road, Onderstepoort, 0110, Pretoria, South Africa
| | - Thandeka Khoza
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville 3209, KwaZulu-Natal, South Africa
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Matsiela MS, Naicker L, Khoza T, Mokoena N. Safety and immunogenicity of inactivated Rift Valley Fever Smithburn viral vaccine in sheep. Virol J 2023; 20:221. [PMID: 37789354 PMCID: PMC10548704 DOI: 10.1186/s12985-023-02180-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 09/07/2023] [Indexed: 10/05/2023] Open
Abstract
BACKGROUND The live-attenuated Rift Valley Fever Smithburn (SB) vaccine is one of the oldest products widely used in ruminants for control of RVF infections. Vaccinations with RVF Smithburn result in residual pathogenic effect and is limited for use in non-pregnant animals. Commercially available RVFV inactivated vaccines are considered safer options to control the disease. These products are prepared from virulent RVFV isolates and present occupational safety concerns. This research study evaluates the ability of an inactivated SB vaccine strain to elicit neutralising antibody response in sheep. METHODS The RVF Smithburn vaccine was inactivated with binary ethylenimine at 37 °C. Inactivated RVFV cultures were adjuvanted with Montande™ Gel-01 and aluminium hydroxide (Al (OH)3) gel for immunogenicity and safety determination in sheep. The commercial RVF inactivated vaccine and a placebo were included as positive and negative control groups, respectively. RESULTS Inactivated RVFV vaccine formulations were safe with all animals showing no clinical signs of RVFV infection and temperature reactions following prime-boost injections. The aluminium hydroxide formulated vaccine induced an immune response as early as 14 days post primary vaccination with neutralising antibody titre of 1:20 and a peak antibody titre of 1:83 was reached on day 56. A similar trend was observed in the animal group vaccinated with the commercial inactivated RVF vaccine obtaining the highest antibody titre of 1:128 on day 56. The neutralizing antibody levels remained within a threshold for the duration of the study. Merino sheep vaccinated with Montanide™ Gel-01-Smithburn were characterised with overall lower immune response when compared to aluminium hydroxide vaccine emulsions. CONCLUSIONS These finding suggests that the inactivated RVF Smithburn vaccine strain adjuvanted with aluminium-hydroxide can be used an alternative to the products prepared from virulent RVFV isolates for protection of ruminants against the disease. The vaccine can further be evaluated for safety in pregnant ewes.
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Affiliation(s)
- Matome Selina Matsiela
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville, 3209, KwaZulu-Natal, South Africa
| | - Leeann Naicker
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa
| | - Thandeka Khoza
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville, 3209, KwaZulu-Natal, South Africa.
| | - Nobalanda Mokoena
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa.
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Suwankitwat N, Bhakha K, Molee L, Songkasupa T, Puangjinda K, Chamchoy T, Arjkumpa O, Nuansrichay B, Srisomrun S, Pongphitcha P, Lekcharoensuk P, Arunvipas P. Long-term monitoring of immune response to recombinant lumpy skin disease virus in dairy cattle from small-household farms in western Thailand. Comp Immunol Microbiol Infect Dis 2023; 99:102008. [PMID: 37467568 DOI: 10.1016/j.cimid.2023.102008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/13/2023] [Accepted: 06/19/2023] [Indexed: 07/21/2023]
Abstract
Lumpy skin disease (LSD) was firstly reported in Thailand in 2021 which affected the cattle industry. However, there is limited information on the immune response of LSDV infection in Thailand where recombinant vaccine strain circulated. The aim of this research was to study the duration of LSD immune response of subclinical and clinical animals after natural infection in dairy cattle. Sixty-six dairy cattle from ten farms in central and western regions of Thailand were investigated. Antibody was detected by virus neutralization test and ELISA. Cell mediated immunity (CMI)-related cytokine gene expressions were evaluated. Antibody was detected until at least 15 months after the noticeable symptom. Cattle with subclinical disease had lower antibody levels compared to animals which had clinical disease. IFN-γ and TNF-α levels were increased, while IL-10 level was decreased in the infected animals compared to the controls. This study elucidated immune responses in dairy cattle herd affected by recombinant LSDV.
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Affiliation(s)
- Nutthakarn Suwankitwat
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Bangkhen campus, Kasetsart University, Bangkok 10900, Thailand; Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Kultyarat Bhakha
- Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Lamul Molee
- Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Tapanut Songkasupa
- Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Kanokwan Puangjinda
- Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Tapakorn Chamchoy
- Epidemiology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Orapun Arjkumpa
- The 4th Regional Livestock Office, Department of Livestock Development, Khon Kaen 40260, Thailand.
| | - Bandit Nuansrichay
- Virology section, National Institute of Animal Health, Department of Livestock Development, Bangkok 10900, Thailand.
| | - Smit Srisomrun
- Bovine Unit, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
| | - Phitcha Pongphitcha
- Bovine Unit, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
| | - Porntippa Lekcharoensuk
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Bangkhen campus, Kasetsart University, Bangkok 10900, Thailand.
| | - Pipat Arunvipas
- Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
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Whittle L, Chapman R, Douglass N, Jaffer M, Margolin E, Rybicki E, Williamson AL. Development of a dual vaccine against East Coast fever and lumpy skin disease. Front Immunol 2023; 14:1143034. [PMID: 37063887 PMCID: PMC10098110 DOI: 10.3389/fimmu.2023.1143034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023] Open
Abstract
East Coast fever is an acute bovine disease caused by the apicomplexan parasite Theileria parva and is regarded as one of the most important tick-vectored diseases in Africa. The current vaccination procedure has many drawbacks, as it involves the use of live T. parva sporozoites. As a novel vaccination strategy, we have constructed the recombinant lumpy skin disease virus (LSDV) named LSDV-SODis-p67HA-BLV-Gag, encoding a modified form of the T. parva p67 surface antigen (p67HA), as well as the bovine leukemia virus (BLV) gag gene for the formation of virus-like particles (VLPs) to potentially enhance p67 immunogenicity. In place of the native sequence, the chimeric p67HA antigen has the human tissue plasminogen activator signal sequence and the influenza hemagglutinin A2 transmembrane domain and cytoplasmic tail. p67HA was detected on the surface of infected cells, and VLPs comprising BLV Gag and p67HA were produced. We also show that higher multiple bands observed in western blot analysis are due to glycosylation of p67. The two vaccines, pMExT-p67HA (DNA) and LSDV-SODis-p67HA-BLV-Gag, were tested for immunogenicity in mice. p67-binding antibodies were produced by vaccinated animals, with higher titers detected in mice vaccinated with the recombinant LSDV. This candidate dual vaccine warrants further testing in cattle.
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Affiliation(s)
- Leah Whittle
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Ros Chapman
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- *Correspondence: Ros Chapman,
| | - Nicola Douglass
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Mohamed Jaffer
- Electron Microscope Unit, University of Cape Town, Cape Town, South Africa
| | - Emmanuel Margolin
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Biopharming Research Unit, Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Cape Town, South Africa
| | - Edward Rybicki
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Biopharming Research Unit, Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Cape Town, South Africa
| | - Anna-Lise Williamson
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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Lumpy Skin Disease—An Emerging Cattle Disease in Europe and Asia. Vaccines (Basel) 2023; 11:vaccines11030578. [PMID: 36992162 DOI: 10.3390/vaccines11030578] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/06/2023] Open
Abstract
Lumpy skin disease virus (LSDV) is a member of the Capripoxvirus genus, mainly infecting cattle and buffalo, which until relatively recently was only endemic in parts of Africa and then spread to the Middle East and lately Europe and Asia. Lumpy skin disease (LSD) is a notifiable disease with a serious impact on the beef industry as it causes mortality of up to 10% and has impacts on milk and meat production, as well as fertility. The close serological relationship between LSDV, goat poxvirus (GTPV) and sheep poxvirus (SPPV) has led to live attenuated GTPV and SPPV vaccines being used to protect against LSD in some countries. There is evidence that the SPPV vaccine does not protect from LSD as well as the GTPV and LSDV vaccines. One of the LSD vaccines used in Eastern Europe was found to be a combination of different Capripoxviruses, and a series of recombination events in the manufacturing process resulted in cattle being vaccinated with a range of recombinant LSDVs resulting in virulent LSDV which spread throughout Asia. It is likely that LSD will become endemic throughout Asia as it will be very challenging to control the spread of the virus without widespread vaccination.
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Moetlhoa B, Tjale M, Pretorius A, Hayeshi R, Grobler A, Mokoena NB. Rift Valley Fever vaccine strategies: Enhanced stability of RVF Clone 13. Vaccine 2023; 41:1050-1058. [PMID: 36593173 DOI: 10.1016/j.vaccine.2022.12.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 01/02/2023]
Abstract
Rift Valley Fever virus (RVFV) causes the zoonotic RVF disease, which results in substantial economic losses in livestock industries. Regular vaccination of livestock against RVF is necessary to generate long-term immunity and avoid the loss of livestock. The live attenuated vaccine based on Clone 13 virus strain has been used to reduce the negative impact of RVF disease. The vaccine strain is heat labile and requires stringent conditions for storage and handling. This research evaluated lactose and sucrose-based stabilizers coupled with lyophilisation to enhance stability of the RVF Clone 13 vaccine strain. The glass transition temperature (Tg) of the sucrose-RVF vaccine was 97.0 °C with average residual moisture of below 2 %. The lactose formulation was characterised with Tg of 83.5 °C and residual moisture of above 2 %. The RVF Clone 13 sucrose-based formulation maintained higher antigen titres during lyophilisation compared to the lactose-formulated vaccine. Cellular-mediated and humoral immunity was evaluated and compared for the two newly formulated vaccines. Pheroid® technology was also investigated as a potential adjuvant and its ability to further enhance the immunogenicity conferred by the RVF Clone 13 vaccine formulations in Merino sheep. No adverse reactions were observed following injection of the vaccine formulations in mice, guinea pigs and Merino sheep. Comparable protective humoral immune responses against RVF were obtained for all animals vaccinated with the lactose and sucrose-based stabilisers with and without the Pheroid® adjuvant. No proliferation of CD8+ and CD4+ T-cells as well as expression of IFN-γ was observed for all animals group vaccinated with Pheroid® only. Specific CD8+ IFN-γ+T-cells were expressed at higher levels compared to the CD4+ IFN-γ+T-cells in the RVF Clone 13 vaccines, suggesting that cellular immunity against RVF is through the Class I antigen presentation pathway.
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Affiliation(s)
- Boitumelo Moetlhoa
- Onderstepoort Biological Products (OBP) SOC Ltd, 100 Old Soutpan Road, Onderstepoort, 0110, South Africa; DSI/NWU Preclinical Drug Development Platform (PCDDP), Faculty of Health Sciences, North-West University, Potchefstroom 2520, South Africa
| | - Mabotse Tjale
- Onderstepoort Biological Products (OBP) SOC Ltd, 100 Old Soutpan Road, Onderstepoort, 0110, South Africa; Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Meiring Naudé Road Brummeria, Pretoria, South Africa
| | - Alri Pretorius
- ARC-Onderstepoort Veterinary Research (OVR), 100 Old Soutpan Road, Onderstepoort, 0110, South Africa
| | - Rose Hayeshi
- DSI/NWU Preclinical Drug Development Platform (PCDDP), Faculty of Health Sciences, North-West University, Potchefstroom 2520, South Africa
| | - Anne Grobler
- DSI/NWU Preclinical Drug Development Platform (PCDDP), Faculty of Health Sciences, North-West University, Potchefstroom 2520, South Africa
| | - Nobalanda B Mokoena
- Onderstepoort Biological Products (OBP) SOC Ltd, 100 Old Soutpan Road, Onderstepoort, 0110, South Africa.
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Matsiela MS, Naicker L, Dibakwane VS, Ntombela N, Khoza T, Mokoena N. Improved safety profile of inactivated Neethling strain of the Lumpy Skin Disease Vaccine. Vaccine X 2022; 12:100209. [PMID: 36051749 PMCID: PMC9424558 DOI: 10.1016/j.jvacx.2022.100209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/29/2022] [Accepted: 08/11/2022] [Indexed: 11/25/2022] Open
Abstract
The Lumpy Skin Disease Virus (LSDV) Neethling vaccine strains have been used for decades for prophylactic immunization of domestic ruminants against the disease. Commercial products against Lumpy skin disease are supplied as live attenuated vaccines and often are associated with adverse reactions warranting studies towards development of safe and efficacious vaccine alternatives. The present study was designed to investigate the ability of Montanide™ Gel 01 PR adjuvanted inactivated Neethling vaccine strain of the lumpy skin disease to induce immune response in rabbits. Complete virus inactivation was achieved following treatment of live vaccine strain with binary ethyleneimine (BEI) at 2 mM final concentration. Inactivated virus antigen, formulated with Montanide™ Gel 01 was injected at 1,00E + 05 and 1,00E + 06 TCID50 per dose in rabbits. The second injection with same vaccine dosages was administered 21 days after the primary vaccination. Rabbits that received a 1,00E + 05 TCID50/dose of inactivated LSDV vaccine formulation induced maximum neutralizing antibody titres on day 13 post second vaccinations. Rabbits vaccinated and prime boosted with the 1,00E + 06 TCID50/dose of inactivated LSDV vaccine formulation, induced neutralizing antibody titres on day 14 after first vaccination. The maximum antibody titres for the 1,00E + 06 TCID50/dose of the inactivated LSDV vaccine formulation was obtained on day 35 post vaccination. The 1,00E + 06 TCID50 dose of the inactivated LSDV vaccine Montanide™ Gel-01 PR formulation induced higher neutralizing antibodies. The MontanideTM Gel-01 PR offers safer profile to oil adjuvants and can be developed further to protect target animals against LSDV in non-endemic areas.
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11
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Immune correlates of protection following Rift Valley fever virus vaccination. NPJ Vaccines 2022; 7:129. [PMID: 36307416 PMCID: PMC9616434 DOI: 10.1038/s41541-022-00551-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 10/11/2022] [Indexed: 11/27/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a hemorrhagic fever virus with the potential for significant economic and public health impact. Vaccination with an attenuated strain, DelNSsRVFV, provides protection from an otherwise lethal RVFV challenge, but mechanistic determinants of protection are undefined. In this study, a murine model was used to assess the contributions of humoral and cellular immunity to DelNSsRVFV-mediated protection. Vaccinated mice depleted of T cells were protected against subsequent challenge, and passive transfer of immune serum from vaccinated animals to naïve animals was also protective, demonstrating that T cells were dispensable in the presence of humoral immunity and that humoral immunity alone was sufficient. Animals depleted of B cells and then vaccinated were protected against challenge. Total splenocytes, but not T cells alone, B cells alone, or B + T cells harvested from vaccinated animals and then transferred to naïve animals were sufficient to confer protection, suggesting that multiple cellular interactions were required for effective cellular immunity. Together, these data indicate that humoral immunity is sufficient to confer vaccine-mediated protection and suggests that cellular immunity plays a role in protection that requires the interaction of various cellular components.
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12
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Sprygin A, Mazloum A, van Schalkwyk A, Babiuk S. Capripoxviruses, leporipoxviruses, and orthopoxviruses: Occurrences of recombination. Front Microbiol 2022; 13:978829. [PMID: 36274700 PMCID: PMC9584655 DOI: 10.3389/fmicb.2022.978829] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Poxviruses are double-stranded DNA viruses with several members displaying restricted host ranges. They are genetically stable with low nucleotide mutation rates compared to other viruses, due to the poxviral high-fidelity DNA polymerase. Despite the low accumulation of mutations per replication cycle, poxvirus genomes can recombine with each other to generate genetically rearranged viruses through recombination, a process directly associated with replication and the aforementioned DNA polymerase. Orthopoxvirus replication is intimately tethered to high frequencies of homologous recombination between co-infecting viruses, duplicated sequences of the same virus, and plasmid DNA transfected into poxvirus-infected cells. Unfortunately, the effect of these genomic alterations on the cellular context for all poxviruses across the family Poxviridae remains elusive. However, emerging sequence data on currently circulating and archived poxviruses, such as the genera orthopoxviruses and capripoxviruses, display a wide degree of divergence. This genetic variability cannot be explained by clonality or genetic drift alone, but are probably a result of significant genomic alterations, such as homologous recombination, gene loss and gain, or gene duplications as the major selection forces acting on viral progeny. The objective of this review is to cross-sectionally overview the currently available findings on natural and laboratory observations of recombination in orthopoxviruses, capripoxviruses, and leporipoxviruses, as well as the possible mechanisms involved. Overall, the reviewed available evidence allows us to conclude that the current state of knowledge is limited in terms of the relevance of genetic variations across even a genus of poxviruses as well as fundamental features governing and precipitating intrinsic gene flow and recombination events.
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Affiliation(s)
- Alexander Sprygin
- Federal Center for Animal Health, Vladimir, Russia
- *Correspondence: Alexander Sprygin,
| | - Ali Mazloum
- Federal Center for Animal Health, Vladimir, Russia
| | | | - Shawn Babiuk
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada
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13
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Zhang S, Yan F, Liu D, Li E, Feng N, Xu S, Wang H, Gao Y, Yang S, Zhao Y, Xia X. Bacterium-Like Particles Displaying the Rift Valley Fever Virus Gn Head Protein Induces Efficacious Immune Responses in Immunized Mice. Front Microbiol 2022; 13:799942. [PMID: 35369468 PMCID: PMC8969503 DOI: 10.3389/fmicb.2022.799942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/03/2022] [Indexed: 11/13/2022] Open
Abstract
Rift Valley fever virus (RVFV), a mosquito-borne zoonotic phlebovirus, causes serious disease in humans and ruminants. According to the World Health Organization, Rift Valley fever is classified as a priority disease, and as such, vaccine development is of high priority due to the lack of licensed vaccines. In this study, a bacterium-like particle vaccine (BLP), RVFV-BLPs, is constructed. A novel display system is described, which is based on non-living and non-genetically modified Gram-positive bacterial cells, designated as Gram-positive enhancer matrix (GEM). The RVFV Gn head protein was displayed on the surface of GEM by co-expression with the peptidoglycan-binding domain (protein anchor) at the C-terminus. We determined that the RVFV Gn head-PA fusion protein was successfully displayed on the GEM. Mice immunized with RVFV-BLPs produced humoral and cellular immunity. Interestingly, comparing the production of RVFV Gn head-specific IgG and its subtype by vaccinating with different antigen doses of the RVFV-BLPs determined that the RVFV-BLPs (50 μg) group showed a greater effect than the other two groups. More importantly, antibodies produced by mice immunized with RVFV-BLPs (50 μg) exhibited potent neutralizing activity against RVFV pseudovirus. RVFV-BLPs (50 μg) also could induce IFN-γ and IL-4 in immunized mice; these mice generated memory cells among the proliferating T cell population after immunization with RVFV-BLPs with effector memory T cells as the major population, which means that RVFV-BLPs is an effective vaccine to establish a long-lived population of memory T cells. The findings suggest that the novel RVFV-BLPs subunit vaccine has the potential to be considered a safe and effective candidate vaccine against RVFV infection.
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Affiliation(s)
- Shengnan Zhang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Feihu Yan
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Dongping Liu
- The Nanjing Unicorn Academy of Innovation, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Nanjing, China
| | - Entao Li
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Na Feng
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Shengnan Xu
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Hualei Wang
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yuwei Gao
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Songtao Yang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- *Correspondence: Songtao Yang,
| | - Yongkun Zhao
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- Yongkun Zhao,
| | - Xianzhu Xia
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- Xianzhu Xia,
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14
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Boshra H, Teffera M, Cao J, Babiuk S. Cloning Strategies for the Generation of Recombinant Capripoxvirus Through the Use of Screening and Selection Markers. Methods Mol Biol 2022; 2465:195-207. [PMID: 35118623 DOI: 10.1007/978-1-0716-2168-4_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The ability to manipulate capripoxvirus through gene knockouts and gene insertions has become an increasingly valuable research tool in elucidating the function of individual genes of capripoxvirus, as well as in the development of capripoxvirus-based recombinant vaccines. The homologous recombination technique is commonly used to generate capripoxvirus knockout viruses (KO), and is based on the targeting of a particular viral gene of interest. This technique can also be used to insert a gene of interest. A protocol for the generation of a viral gene knockout is described. This technique involves the use of a plasmid which encodes the flanking sequences of the regions where the homologous recombination will occur, and will result in the insertion of an EGFP reporter gene for visualization of recombinant virus, as well as the E. coli gpt gene as a positive selection marker. If an additional gene is to be incorporated, this can be achieved by inserting a gene of interest for expression under a poxvirus promoter into the plasmid between the flanking regions for insertion. This chapter describes a protocol for generating such recombinant capripoxviruses. An alternative step for the removal of both the EGFP and gpt cassettes and an optional selection step using CRISPR technology are also described.
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Affiliation(s)
- Hani Boshra
- Department of Pathology, Fundamental and Applied Research for Animals and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Liège, Belgium.
| | - Mahder Teffera
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada
| | - Jinxing Cao
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Shawn Babiuk
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada.
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15
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Chapman R, van Diepen M, Douglass N, Galant S, Jaffer M, Margolin E, Ximba P, Hermanus T, Moore PL, Williamson AL. Assessment of an LSDV-Vectored Vaccine for Heterologous Prime-Boost Immunizations against HIV. Vaccines (Basel) 2021; 9:1281. [PMID: 34835214 PMCID: PMC8620012 DOI: 10.3390/vaccines9111281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/18/2021] [Accepted: 10/27/2021] [Indexed: 11/18/2022] Open
Abstract
The modest protective effects of the RV144 HIV-1 vaccine trial have prompted the further exploration of improved poxvirus vector systems that can yield better immune responses and protection. In this study, a recombinant lumpy skin disease virus (LSDV) expressing HIV-1 CAP256.SU gp150 (Env) and a subtype C mosaic Gag was constructed (LSDVGC5) and compared to the equivalent recombinant modified vaccinia Ankara (MVAGC5). In vitro characterization confirmed that cells infected with recombinant LSDV produced Gag virus-like particles containing Env, and that Env expressed on the surface of the cells infected with LSDV was in a native-like conformation. This candidate HIV-1 vaccine (L) was tested in a rabbit model using different heterologous vaccination regimens, in combination with DNA (D) and MVA (M) vectors expressing the equivalent HIV-1 antigens. The four different vaccination regimens (DDMMLL, DDMLML, DDLMLM, and DDLLMM) all elicited high titers of binding and Tier 1A neutralizing antibodies (NAbs), and some regimens induced Tier 1B NAbs. Furthermore, two rabbits in the DDLMLM group developed low levels of autologous Tier 2 NAbs. The humoral immune responses elicited against HIV-1 Env by the recombinant LSDVGC5 were comparable to those induced by MVAGC5.
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Affiliation(s)
- Ros Chapman
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Michiel van Diepen
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Nicola Douglass
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Shireen Galant
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Mohamed Jaffer
- Electron Microscope Unit, University of Cape Town, Rondebosch 7701, South Africa;
| | - Emmanuel Margolin
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Phindile Ximba
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Tandile Hermanus
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2131, South Africa; (T.H.); (P.L.M.)
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Penny L. Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2131, South Africa; (T.H.); (P.L.M.)
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, Durban 4013, South Africa
| | - Anna-Lise Williamson
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
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16
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Douglass N, Omar R, Munyanduki H, Suzuki A, de Moor W, Mutowembwa P, Pretorius A, Nefefe T, van Schalkwyk A, Kara P, Heath L, Williamson AL. The Development of Dual Vaccines against Lumpy Skin Disease (LSD) and Bovine Ephemeral Fever (BEF). Vaccines (Basel) 2021; 9:vaccines9111215. [PMID: 34835146 PMCID: PMC8621795 DOI: 10.3390/vaccines9111215] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 12/21/2022] Open
Abstract
Dual vaccines (n = 6) against both lumpy skin disease (LSD) and bovine ephemeral fever (BEF) were constructed, based on the BEFV glycoprotein (G) gene, with or without the BEFV matrix (M) protein gene, inserted into one of two different LSDV backbones, nLSDV∆SOD-UCT or nLSDVSODis-UCT. The inserted gene cassettes were confirmed by PCR; and BEFV protein was shown to be expressed by immunofluorescence. The candidate dual vaccines were initially tested in a rabbit model; neutralization assays using the South African BEFV vaccine (B-Phemeral) strain showed an African consensus G protein gene (Gb) to give superior neutralization compared to the Australian (Ga) gene. The two LSDV backbones expressing both Gb and M BEFV genes were tested in cattle and shown to elicit neutralizing responses to LSDV as well as BEFV after two inoculations 4 weeks apart. The vaccines were safe in cattle and all vaccinated animals were protected against virulent LSDV challenge, unlike a group of control naïve animals, which developed clinical LSD. Both neutralizing and T cell responses to LSDV were stimulated upon challenge. After two inoculations, all vaccinated animals produced BEFV neutralizing antibodies ≥ 1/20, which is considered protective for BEF.
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Affiliation(s)
- Nicola Douglass
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
- Correspondence: ; Tel.: +27-832-310-553
| | - Ruzaiq Omar
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Henry Munyanduki
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Akiko Suzuki
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Warren de Moor
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Paidamwoyo Mutowembwa
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Alri Pretorius
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Tshifhiwa Nefefe
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Antoinette van Schalkwyk
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Pravesh Kara
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Livio Heath
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Anna-Lise Williamson
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
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17
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Tuppurainen E, Dietze K, Wolff J, Bergmann H, Beltran-Alcrudo D, Fahrion A, Lamien CE, Busch F, Sauter-Louis C, Conraths FJ, De Clercq K, Hoffmann B, Knauf S. Review: Vaccines and Vaccination against Lumpy Skin Disease. Vaccines (Basel) 2021; 9:1136. [PMID: 34696244 PMCID: PMC8539040 DOI: 10.3390/vaccines9101136] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/24/2021] [Accepted: 09/29/2021] [Indexed: 11/16/2022] Open
Abstract
The geographical distribution of lumpy skin disease (LSD), an economically important cattle disease caused by a capripoxvirus, has reached an unprecedented extent. Vaccination is the only way to prevent the spread of the infection in endemic and newly affected regions. Yet, in the event of an outbreak, selection of the best vaccine is a major challenge for veterinary authorities and farmers. Decision makers need sound scientific information to support their decisions and subsequent actions. The available vaccine products vary in terms of quality, efficacy, safety, side effects, and price. The pros and cons of different types of live attenuated and inactivated vaccines, vaccination strategies, and associated risks are discussed. Seroconversion, which typically follows vaccination, places specific demands on the tools and methods used to evaluate the effectiveness of the LSD vaccination campaigns in the field. We aimed to give a comprehensive update on available vaccines and vaccination against LSD, to better prepare affected and at-risk countries to control LSD and ensure the safe trade of cattle.
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Affiliation(s)
- Eeva Tuppurainen
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (K.D.); (A.F.); (F.B.); (S.K.)
| | - Klaas Dietze
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (K.D.); (A.F.); (F.B.); (S.K.)
| | - Janika Wolff
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (J.W.); (B.H.)
| | - Hannes Bergmann
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (H.B.); (C.S.-L.); (F.J.C.)
| | - Daniel Beltran-Alcrudo
- Regional Office for Europe and Central Asia, Food and Agriculture Organization, 20 Kalman Imre utca, H-1054 Budapest, Hungary;
| | - Anna Fahrion
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (K.D.); (A.F.); (F.B.); (S.K.)
| | - Charles Euloge Lamien
- FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Department of Nuclear Sciences and Applications, International Atomic Energy Agency (IAEA), Friedenstrasse 1, A-2444 Seibersdorf, Austria;
| | - Frank Busch
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (K.D.); (A.F.); (F.B.); (S.K.)
| | - Carola Sauter-Louis
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (H.B.); (C.S.-L.); (F.J.C.)
| | - Franz J. Conraths
- Institute of Epidemiology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (H.B.); (C.S.-L.); (F.J.C.)
| | - Kris De Clercq
- Unit of Exotic and Particular Diseases, Scientific Directorate Infectious Diseases in Animals, Sciensano, Groeselenberg 99, B-1180 Brussels, Belgium;
| | - Bernd Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (J.W.); (B.H.)
| | - Sascha Knauf
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, D-17493 Greifswald-Insel Riems, Germany; (K.D.); (A.F.); (F.B.); (S.K.)
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18
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van Diepen M, Chapman R, Douglass N, Whittle L, Chineka N, Galant S, Cotchobos C, Suzuki A, Williamson AL. Advancements in the Growth and Construction of Recombinant Lumpy Skin Disease Virus (LSDV) for Use as a Vaccine Vector. Vaccines (Basel) 2021; 9:vaccines9101131. [PMID: 34696239 PMCID: PMC8539341 DOI: 10.3390/vaccines9101131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 01/13/2023] Open
Abstract
Attenuated vaccine strains of lumpy skin disease virus (LSDV) have become increasingly popular as recombinant vaccine vectors, to target both LSDV, as well as other pathogens, including human infectious agents. Historically, these vaccine strains and recombinants were generated in primary (lamb) testis (LT) cells, Madin–Darby bovine kidney (MDBK) cells or in eggs. Growth in eggs is a laborious process, the use of primary cells has the potential to introduce pathogens and MDBK cells are known to harbor bovine viral diarrhea virus (BVDV). In this study, data is presented to show the growth of an attenuated LSDV strain in baby hamster kidney (BHK-21) cells. Subsequently, a recombinant LSDV vaccine was generated in BHK-21 cells. Partial growth was also observed in rabbit kidney cells (RK13), but only when the vaccinia virus host range gene K1L was expressed. Despite the limited growth, the expression of K1L was enough to serve as a positive selection marker for the generation of recombinant LSDV vaccines in RK13 cells. The simplification of generating (recombinant) LSDV vaccines shown here should increase the interest for this platform for future livestock vaccine development and, with BHK-21 cells approved for current good manufacturing practice, this can be expanded to human vaccines as well.
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Affiliation(s)
- Michiel van Diepen
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Rosamund Chapman
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Nicola Douglass
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
- Correspondence: (N.D.); (A.-L.W.); Tel.: +27-832310553 (N.D.)
| | - Leah Whittle
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Nicole Chineka
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Shireen Galant
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Christian Cotchobos
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Akiko Suzuki
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Anna-Lise Williamson
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (R.C.); (L.W.); (N.C.); (S.G.); (C.C.); (A.S.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
- Correspondence: (N.D.); (A.-L.W.); Tel.: +27-832310553 (N.D.)
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19
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Shafik NG, Khafagy HA, AM A, Bassiuony AI, Fouad Zaki F, Mikhael CA, Samy Abousenna M. Comparative study between lumpy skin disease virus and sheep pox virus vaccines against recent field isolate of lumpy skin disease virus. BIONATURA 2021. [DOI: 10.21931/rb/2021.01.03.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Lumpy Skin Disease (LSD) is a vector born disease of cattle, caused by Lumpy Skin Disease Virus (LSDV), there is antigenic relationship between LSDV, Sheeppox virus (SPPV) and Goat pox virus GTPV within a genus Capripoxvirus, accordingly it can be used homologous or heterologous Capripoxvirus strains for vaccination of cattle against LSD. This study compare the efficacy of live attenuated Neethling LSDV vaccine and live attenuated Romanian SSPV Vaccine against recent circulating LSDV field isolate. The evaluation was done in calves as the main host of LSD, through using three different batches for each vaccine type. Experimental calf groups were vaccinated with vaccines batches, and after 21 days serum samples were collected for evaluation of humoral immune response by using SNT and commercial ELISA technique, then the vaccinated calves were challenged by virulent LSDV field isolate. The results of SNT for vaccinated calves by LSDV vaccines indicated mean neutralizing antibody titer 1.2, 1.6 and1.5 log10 for the batches 1, 2 and 3 respectively, while vaccinated calves by SPPV vaccines indicated 1.05, 1.05 and 1.5 log10 for the batches 1,2 and 3 respectively; the ELISA mean sample to positive (S/P) percentage for the vaccine batches 1, 2 and 3 of LSDV were 40, 45 and 42% respectively and for SPPV vaccine batches 1,2 and 3 were 35, 37 and 40 % respectively, the challenge test indicated mean difference titer for the groups of calves vaccinated with LSDV vaccine were 4.2, 4.5 and 3.8 log10 and for groups vaccinated with SPPV vaccine were 2.6, 2 and 2.65 log10 respectively, it was concluded that potential using of Neethling LSDV vaccine against LSD is superior for combating and prevention of the lumpy skin disease.
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Affiliation(s)
- Nermeen G Shafik
- Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agricultural Research Center, Cairo, Egypt
| | - Heba A Khafagy
- Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agricultural Research Center, Cairo, Egypt
| | - Amal AM
- Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agricultural Research Center, Cairo, Egypt
| | - Ayatollah I Bassiuony
- Veterinary Serum and Vaccine Research Institute, Pox department, Agricultural Research Center, Cairo, Egypt
| | - Farid Fouad Zaki
- Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agricultural Research Center, Cairo, Egypt
| | - Christine A Mikhael
- Veterinary Serum and Vaccine Research Institute, Pox department, Agricultural Research Center, Cairo, Egypt
| | - Mohamed Samy Abousenna
- Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agricultural Research Center, Cairo, Egypt
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20
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Safini N, Bamouh Z, Hamdi J, Jazouli M, Tadlaoui KO, El Harrak M. In-vitro and in-vivo study of the interference between Rift Valley fever virus (clone 13) and Sheeppox/Limpy Skin disease viruses. Sci Rep 2021; 11:12395. [PMID: 34117312 PMCID: PMC8196192 DOI: 10.1038/s41598-021-91926-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 05/17/2021] [Indexed: 11/09/2022] Open
Abstract
Viral interference is a common occurrence that has been reported in cell culture in many cases. In the present study, viral interference between two capripox viruses (sheeppox SPPV and lumpy skin disease virus LSDV in cattle) with Rift Valley fever virus (RVFV) was investigated in vitro and in their natural hosts, sheep and cattle. A combination of SPPV/RVFV and LSDV/RVFV was used to co-infect susceptible cells and animals to detect potential competition. In-vitro interference was evaluated by estimating viral infectivity and copies of viral RNA by a qPCR during three serial passages in cell cultures, whereas in-vivo interference was assessed through antibody responses to vaccination. When lamb testis primary cells were infected with the mixture of capripox and RVFV, the replication of both SPPV and LSDV was inhibited by RVFV. In animals, SPPV/RVFV or LSDV/RVFV combinations inhibited the replication SPPV and LSDV and the antibody response following vaccination. The combined SPPV/RVFV did not protect sheep after challenging with the virulent strain of SPPV and the LSDV/RVFV did not induce interferon Gamma to LSDV, while immunological response to RVFV remain unaffected. Our goal was to assess this interference response to RVFV/capripoxviruses’ coinfection in order to develop effective combined live-attenuated vaccines as a control strategy for RVF and SPP/LSD diseases. Our findings indicated that this approach was not suitable for developing a combined SPPV/LSDV/RVFV vaccine candidate because of interference of replication and the immune response among these viruses.
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Affiliation(s)
- N Safini
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco.
| | - Z Bamouh
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - J Hamdi
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - M Jazouli
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - K O Tadlaoui
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - M El Harrak
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
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21
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Hamdi J, Munyanduki H, Omari Tadlaoui K, El Harrak M, Fassi Fihri O. Capripoxvirus Infections in Ruminants: A Review. Microorganisms 2021; 9:902. [PMID: 33922409 PMCID: PMC8145859 DOI: 10.3390/microorganisms9050902] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/24/2021] [Accepted: 03/30/2021] [Indexed: 11/16/2022] Open
Abstract
Lumpy skin disease, sheeppox, and goatpox are notifiable diseases of cattle, sheep, and goats, respectively, caused by viruses of the Capripoxvirus genus. They are responsible for both direct and indirect financial losses. These losses arise through animal mortality, morbidity cost of vaccinations, and constraints to animals and animal products' trade. Control and eradication of capripoxviruses depend on early detection of outbreaks, vector control, strict animal movement, and vaccination which remains the most effective means of control. To date, live attenuated vaccines are widely used; however, conferred protection remains controversial. Many vaccines have been associated with adverse reactions and incomplete protection in sheep, goats, and cattle. Many combination- and recombinant-based vaccines have also been developed. Here, we review capripoxvirus infections and the immunity conferred against capripoxviruses by their respective vaccines for each ruminant species. We also review their related cross protection to heterologous infections.
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Affiliation(s)
- Jihane Hamdi
- Department of Research and Development, Multi-Chemical Industry Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC) B.P., 278, Mohammedia 28810, Morocco; (K.O.T.); (M.E.H.)
| | | | - Khalid Omari Tadlaoui
- Department of Research and Development, Multi-Chemical Industry Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC) B.P., 278, Mohammedia 28810, Morocco; (K.O.T.); (M.E.H.)
| | - Mehdi El Harrak
- Department of Research and Development, Multi-Chemical Industry Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC) B.P., 278, Mohammedia 28810, Morocco; (K.O.T.); (M.E.H.)
| | - Ouafaa Fassi Fihri
- Department of Microbiology, Immunology and Contagious Diseases, Agronomic and Veterinary Institute Hassan II, Madinat Al Irfane, Rabat 6202, Morocco;
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22
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Farmers' preference and willingness to pay for a multivalent lumpy skin disease and Rift Valley fever novel vaccine: A discrete choice experiment in the Free State province, South Africa. Prev Vet Med 2021; 189:105293. [PMID: 33631510 DOI: 10.1016/j.prevetmed.2021.105293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 01/29/2021] [Accepted: 01/31/2021] [Indexed: 11/20/2022]
Abstract
Rift Valley fever and lumpy skin disease are infectious ruminant diseases that are endemic in most African countries. The most cost-effective method of prevention and control is through annual vaccination. However, unlike lumpy skin disease, annual vaccination against Rift Valley fever is not practiced by many farmers due to its sporadic occurrences and shortcoming of the existing vaccines. This necessitates development of novel vaccines that would provide dual protection against a Rift Valley fever and a more prevalent disease. In this study, a discrete choice experiment was undertaken to guide vaccine development by examining the value smallholder livestock farmers place on different vaccine attributes and related attribute levels. The attributes considered are target-species, thermotolerance, nature of the vaccine, efficacy and price. The study was carried out with 164 smallholder livestock farmers in the Free State province. Results indicate that thermostaility is not a major deciding attribute to smallholder farmer's choice of vaccine. Farmers prefer multivalent vaccines, which are highly efficacious with about 90-100 % efficacy levels. Farmers were found to be heterogeneous in preference. The heterogeneity is explained by socio-economic factors such as type of livestock owned, income level, gender and perceived disease risk. Farmers were also willing to pay for preferred attribute levels. However, for less favourable levels such as multispecies, female farmers were willing to accept a lower compensation than males. These findings present a favourable potential for development of a novel multivalent vaccine and also provide vaccine research and development scientists with evidence based knowledge for development of vaccines that cater for the needs of smallholder farmers.
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Capripoxvirus vectors for vaccine development. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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