Protection against Boophilus annulatus infestations in cattle vaccinated with the B. microplus Bm86-containing vaccine Gavac

Fragoso, Hugo; Rad, P.Hoshman; Ortíz, Martín; Rodrı́guez, Manuel; Redondo, María C.; Herrera, Luís; Fuente, José de la

doi:10.1016/s0264-410x(98)00116-9

Cited by 111 publications

(68 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The number of animals per group, considering each animal to be one replicate in each assay, ranged from 3 to 16, and the vast majority (21/25) used 3 to 6 animals per group. Two authors failed to report the number of animals per group (CANALES et al, 1997;FRAGOSO et al, 1998), and three articles used groups with different numbers of animals (ANDREOTTI, 2006;AZHAHIANAMBI et al, 2009a;KUMAR et al, 2012a). Three studies included an unvaccinated negative control group, 21 studies vaccinated with an equal volume of saline and/or adjuvant, and one study failed to report the negative control treatment (CANALES et al, 1997).…”

Section: Resultsmentioning

confidence: 99%

“…Most studies used crossbred animals (17/25). One of these studies worked with groups of crossbred and Holstein animals (CANALES et al, 1997), while another study used crossbred animals and Aberdeen Angus (FRAGOSO et al, 1998). A third study used Nellore and Simmental crossbred animals (ANDREOTTI, 2007).…”

Section: Resultsmentioning

confidence: 99%

“…Eight years later, Canales et al (1997) calculated for the first time the proper efficacy by considering the following three variables for its calculation: total tick production, capacity of oviposition and fertility. Subsequently, Fragoso et al (1998) used these measures when testing the commercial vaccine Gavac TM (Heber Biotec S.A., P.O. Box 6162, Havana, Cuba), which was developed as a Rhipicephalus (Boophilus) microplus control tool, in Rhipicephalus annulatus tick strains isolated from Mexico and Iran.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Calculation of the efficacy of vaccines against tick infestations on cattle

Cunha

Andreotti

Garcia

et al. 2013

Rev. Bras. Parasitol. Vet.

View full text Add to dashboard Cite

Cattle ticks are responsible for great economic losses in cattle farming worldwide, and their main control method, chemicals, has been showing problems, whether resulting from the development of resistant strains of ticks or environmental contamination. Research studies directed toward developing vaccines against ticks are emerging. One way to evaluate those vaccines is to calculate the percentage of efficacy. The aim of this study was to analyze scientific publications archived in PubMed that used this method of assessment and discuss the main factors that may affect its calculation. Thus, 25 articles addressing this subject were selected. The percentage of efficacy was usually calculated in one of two ways, with one considering the reduced fertility of eggs and the other not. The latter method may underestimate the vaccine efficacy, and the most complete formula for calculating the efficacy reflects how much the vaccine actually affects the infestation. In our view, the use of the complete formula for calculating the percentage of efficacy is broader and more representative of the vaccine effect on the tick population.Keywords: Efficiency, ticks, vaccine, bovine. ResumoCarrapatos de bovinos são responsáveis por grandes perdas econômicas para a pecuária bovina mundial e seu principal método de controle, o químico, vem apresentando problemas, seja pelo desenvolvimento de amostras de carrapatos resistentes ou pela contaminação ambiental. Na tentativa de diminuir a utilização dos acaricidas, surgem pesquisas direcionadas ao desenvolvimento de vacinas contra carrapatos. Uma maneira de avaliar essas vacinas é pelo cálculo de percentagem de eficácia. O objetivo deste trabalho foi analisar as publicações científicas indexadas no PubMed que utilizaram este método de avaliação e discutir os principais fatores que podem interferir no seu cálculo. Dessa maneira, selecionaram-se 25 artigos que tratavam desse assunto. A percentagem de eficácia apareceu sendo calculada de duas formas, uma considerando a redução da fertilidade dos ovos e a outra não. Essa última pode subestimar a eficiência da vacina, e a fórmula de cálculo da eficácia mais completa representa o quanto da infestação a vacina realmente reduziu. Em nosso entendimento, a utilização da fórmula completa para o cálculo da percentagem de eficácia é mais abrangente e representativa do efeito da vacina na população de carrapatos.Palavras-chave: Eficiência, carrapato, vacina, bovino.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Calculation of the efficacy of vaccines against tick infestations on cattle

Cunha

Andreotti

Garcia

et al. 2013

Rev. Bras. Parasitol. Vet.

View full text Add to dashboard Cite

show abstract

“…Like the successful anti-tick vaccine, Bm86 (26,27), midgutbased transmission-blocking antigens are immunologically concealed, which would suggest that there is no basis for selection and nothing to drive antigenic variation, as there is with circulating parasites. Some may suggest, however, that the application of immune pressure on natural populations of mosquitoes may lead to the emergence and selection of variant mosquitoes.…”

Section: Discussionmentioning

confidence: 99%

Anti-mosquito midgut antibodies block development of Plasmodium falciparum and Plasmodium vivax in multiple species of Anopheles mosquitoes and reduce vector fecundity and survivorship

Lal

Patterson

Sacci

et al. 2001

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The mosquito midgut plays a central role in the sporogonic development of malaria parasites. We have found that polyclonal sera, produced against mosquito midguts, blocked the passage of Plasmodium falciparum ookinetes across the midgut, leading to a significant reduction of infections in mosquitoes. Anti-midgut mAbs were produced that display broad-spectrum activity, blocking parasite development of both P. falciparum and Plasmodium vivax parasites in five different species of mosquitoes. In addition to their parasite transmission-blocking activity, these mAbs also reduced mosquito survivorship and fecundity. These results reveal that mosquito midgut-based antibodies have the potential to reduce malaria transmission in a synergistic manner by lowering both vector competence, through transmission-blocking effects on parasite development, and vector abundance, by decreasing mosquito survivorship and egg laying capacity. Because the intervention can block transmission of different malaria parasite species in various species of mosquitoes, vaccines against such midgut receptors may block malaria transmission worldwide.O f the several hundred species of Anopheles mosquitoes worldwide, only about 20 are major vectors of human malaria. Several components contribute to this fact, including the propensity of a given species to feed on humans, the average longevity of a mosquito species, and the innate ability of a species to permit development of the parasite (i.e., vector competence). Different intervention strategies attempt to reduce malaria transmission by reducing these various components. Reducing vector competence is the primary objective behind two rapidly evolving areas of research in malaria and other vector-borne diseases, namely the replacement of natural vector populations with populations genetically engineered for refractoriness and transmission-blocking immunity (TBI).Transmission-blocking vaccines in malaria are envisioned to inhibit the developmental stages of the malaria parasites in the mosquito midgut. The first 48 h after ingestion of an infective blood meal is the most critical time period for malaria parasite development within the mosquito. It is during this time that the parasite fertilization takes place and the resulting zygotes transform into motile ookinetes. Ookinetes traverse the midgut and lodge between the basal lamina and midgut epithelia, where they encyst and develop into sporozoite-producing oocysts.Several studies with rodent and human malaria parasites have revealed that the ookinete-to-oocyst transition is the most vulnerable link in sporogonic development of malaria parasites (1-3). Thus, the developing parasite stages in the mosquito midgut provide an ideal target for transmission-blocking vaccines. Efforts in transmission-blocking vaccines in malaria have focused primarily on the use of specific parasite antigens as targets of immune intervention in the mosquito midgut. Antibodies against parasite antigens block fertilization and͞or prevent the movement of ookinetes across the...

show abstract

“…(B.) microplus (ANDREOTTI, 2006) and against closely related species challenges (FRAGOSO et al, 1998;DE VOS et al, 2001;ODONGO et al, 2007). These protection levels reflect the variation between R.…”

Section: Anti-tick Vaccines Currently Availablementioning

confidence: 99%

New approaches toward anti-Rhipicephalus (Boophilus) microplus tick vaccine

Parizi¹,

Pohl²,

Masuda³

et al. 2009

RBPV

View full text Add to dashboard Cite

The tick Rhipicephalus (Boophilus) microplus (formerly Boophilus microplus) is the major ectoparasite affecting livestock in America, Asia, Africa, and Oceania. Conventional tick control is based on the use of acaricides but immunization of bovines with tick gut proteins induces only a partial protective immune response. Based on this information, distinct research groups have explored the possibility of protecting the animals by inducing an immune response against other tick proteins. However, the antigens so far described do not induce the necessary protection for suppressing the use of acaricides. Currently, several groups are engaged in identifying new tick proteins to be used as targets for the development of new vaccines. This approach focuses on the enhancement of the immunogenicity of antigens already tested by incorporating new adjuvants or formulations and by searching for new antigens. This paper reviews the work done by Brazilian researchers to develop a vaccine against this tick.Keywords: Boophilus microplus, Rhipicephalus microplus, vaccine, tick, control. ResumoO carrapato Rhipicephalus (Boophilus) microplus (anteriormente Boophilus microplus) é o principal ectoparasita que afeta bovinos na América, Ásia, África e Oceania e o seu controle é tradicionalmente realizado através do uso de acaricidas. Experimentos de imunização com proteínas do carrapato mostram que a resposta imune desenvolvida pelos bovinos vacinados protege, em parte, os animais do parasitismo. Baseado nessas observações, vários grupos de pesquisa exploram a possibilidade de proteger os animais pela indução de uma resposta imune contra proteínas do carrapato. Entretanto, os antígenos já caracterizados não asseguram o grau de proteção necessário para suprimir o uso de acaricidas. Portanto, esses grupos de pesquisa estão engajados na tentativa de identificar novas proteínas que possam ser utilizadas para o desenvolvimento de novas vacinas, as quais possam induzir maior imunogenicidade de que os antígenos já testados, através do uso de novas formulações e/ou pela incorporação de adjuvantes. O presente artigo apresenta uma revisão da literatura sobre os resultados obtidos por pesquisadores brasileiros no desenvolvimento de vacinas contra o carrapato.

show abstract

Protection against Boophilus annulatus infestations in cattle vaccinated with the B. microplus Bm86-containing vaccine Gavac

Cited by 111 publications

References 7 publications

Calculation of the efficacy of vaccines against tick infestations on cattle

Calculation of the efficacy of vaccines against tick infestations on cattle

Anti-mosquito midgut antibodies block development of Plasmodium falciparum and Plasmodium vivax in multiple species of Anopheles mosquitoes and reduce vector fecundity and survivorship

New approaches toward anti-Rhipicephalus (Boophilus) microplus tick vaccine

Contact Info

Product

Resources

About