Tekilegiorgis T1* and Tamir D2
1Department of Quality and Safety Assurance Directorate, Ethiopia.
2Department of Veterinary Microbiology, Ethiopia
*Corresponding author: Tamirat Tekilegiorgis, Department of Quality and safety assurance Directorate, Microbiology Laboratory Team Leader, Ethiopia
Submission: September 12, 2019;Published: November 12, 2019
ISSN: 2576-9162 Volume7 Issue2
Lumpy skin disease is of significant economic impact for the cattle industry in Africa. Due to cross protection within the Capri poxvirus genus, sheep poxvirus (SPPV) vaccines have been widely used for cattle against lumpy skin disease virus (LSDV). In the Middle East and the Horn of Africa, these vaccines have been associated with incomplete protection and adverse reactions in cattle post vaccination. The different studies confirm that the real identity of the commonly used Kenyan sheep and goat pox vaccine virus (KSGP) O-240 is not SPPV but is actually LSDV. The low-level attenuation of this virus is likely to be not sufficient for safe use in cattle, causing clinical disease in vaccinated animals. In addition, Isiolo and Kedong goat pox strains, capable of infecting sheep, goats and cattle are identified for potential use as broad-spectrum vaccine candidates against all capripox diseases.
keywords Lumpy skin disease; Goat pox; Sheep pox
Abbreviations: LSDV: Lumpy Skin Disease Virus; SPPV: Sheeppox Virus
Lumpy skin disease (LSD) is a transboundary high impact cattle pox disease characterized by fever, skin and visceral nodules is caused by lumpy skin disease virus (LSDV) from the family Poxviridae, genus Capri poxvirus. Sheep pox virus and Goat pox virus are the two other virus species in this genus. All the vaccines used to prevent LSD are currently based on live attenuated viruses. These vaccines can be roughly divided into homologous vaccines and heterologous vaccines. The homologous vaccines are based on attenuated LSD viruses (LSDV) whereas the heterologous vaccines are based on attenuated sheep pox or goat pox viruses . Good protection in cattle against highly virulent Ethiopian LSD field strain . Ideal product both LSD and GTP Practically has no side effects in cattle and reduces the price. Sheeppox virus (SPPV) vaccines against has 10 times stronger dose than used for sheep is commonly used for cattle in the Middle East.
The Neethling strain based vaccines are cell adapted viruses of the original Neethling LSDV. Two producers currently manufacture these vaccines in South Africa. The Neethling vaccine was four times more effective than the sheep pox vaccine for preventing a laboratory confirmed disease that is, its relative vaccine effectiveness was 77%. Of the cows vaccinated with the attenuated Neethling vaccine, 0.38% developed an adverse effect as a result of the vaccination; this was mostly very mild and was characterized by the appearance of small lumps over the body. In a small scale study in Ethiopia, a Neethling strain vaccine manufactured by the National Ethiopian Veterinary Institute failed to protect calves from challenge by a virulent LSDV strain .Kenyan goat and sheep pox vaccines
The KSGP-180 and KSGP-240 viruses were collected from infected sheep and goats during outbreaks of sheep and goat pox in Kenya in the 1970s. The former was attenuated by 18 passages in bovine foetal muscle cells; the latter was only passaged six times in cell cultures. KS-1 is a virus derived from attenuated KSGP-240; it was also used as a vaccine against LSD, KSGP and hence KS-1 was shown to be a strain of LSDV . Two retrospective studies in Ethiopia report that the KS-1 vaccine was ineffective for protection against LSDV , but there are field reports from Kenya that the KGSP-180 vaccine is safe and protective . A mixture of two recombinant KS-1 vaccines expressing either the haemagglutinin or fusion proteins of Rinderpest virus did not elicit adverse effects and showed protection from challenge with a virulent Neethling strain of LSDV in 5/5 zebu cattle six months after vaccination, in 4/5 after 12 months, in 4/4 after two years and 2/5 after three years . Vaccination of dairy cattle in Israel during 1992 with the KSGP-240 caused a high rate of vaccine associated adverse effects. These were characterized by typical generalized LSD intradermal skin lesions, fever, eye and nose secretions, enlarged lymph nodes, anorexia and a clear decline in milk yield .Attenuated goat pox vaccines
Several studies have shown the efficacy of goat-pox strains for protecting cattle from challenge by LSDV. The Kedong and Isiolo strains were isolated from sheep in Kenya during the 1950s, and were later shown to be goat pox viruses . Both were shown to protect cattle from LSDV challenge. In a recent study a commercial vaccine based on an attenuated Gorgon strain of goat pox virus isolated in Iran was administered at two doses to ten calves, five in each dose group. All calves were completely protected from challenge by a wild Ethiopian strain of LSDV. No adverse effects were observed in the vaccinated calves .Sheep pox vaccines
Currently there is not enough evidence confirming efficacy of for sheep pox based vaccines, though until recently it was believed that vaccination by sheep pox vaccines could provide protection from infection by LSDV. This probably wrong concept was based on the genetic similarity between the different capripox viruses. Earlier studies using thought to be sheep pox strains provided protection from challenge by LSDV, increased the confidence that such cross protection in fact exists. However, these were later shown as actually LSDV or goat pox strains . To date, the sheep pox strains that have been used most to vaccinate against LSDV include the Romanian strain, the Yugoslavian RM-65 strain and the Bakirkoy strain used in Turkey. The Romanian sheep pox virus strain was also used in Egypt  and although it was claimed that it immunized cattle  and that it provided protection from challenge. The vaccine was shown to be ineffective in controlling the outbreak of LSD. The dose was therefore increased by a factor of ten. At this dose, however, the vaccine was demonstrated to be still significantly inferior to a Neethling vaccine used at the same dose .
The Neethling strain based vaccines are cell-adapted viruses of the original Neethling LSDV. These vaccines are currently manufactured in South Africa. The Neethling vaccine was four times more effective than the sheep pox vaccine for preventing a laboratory confirmed disease that is, its relative vaccine effectiveness was 77% Full protection is provided by this vaccine about one month after vaccination, though there is evidence that it is effective in certain individuals at two weeks as well. This vaccine might cause a mild adverse effect characterized by multiple small lumps on the skin, similar to the lesions formed during LSD. Sheep pox and Goat pox vaccine has cross protection and so used for immunization of cattle against LSD.
© 2019 Tekilegiorgis T. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and build upon your work non-commercially.