Delayed reduction of Anaplasma marginale parasitemia and packed cell volume normalization despite prolonged enrofloxacin treatment of cattle co-infected with Trypanosoma vivax

Bastos, Thiago Souza Azeredo; Cruvinel, Leonardo Bueno; Ferreira, Lorena Lopes; Nicaretta, João Eduardo; Couto, Luiz Fellipe Monteiro; Zapa, Dina María Beltrán; Cavalcante, Alliny Souza de Assis; Heller, Luciana Maffini; Salvador, Vanessa Ferreira; Leal, Luccas Lourenzo Lima Lins; Morais, Igor Maciel Lopes de; Soares, Vando Edésio; Cadioli, Fabiano Antônio; Lopes, Welber Daniel Zanetti

doi:10.1007/s00436-021-07226-4

Cited by 6 publications

(2 citation statements)

References 18 publications

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“…The disease is also linked to lowered milk production, reduced working power and reproductive failure ( 3 , 10 ). Moreover, the immunomodulatory effects of AT may adversely affect the efficacy of vaccines ( 11 ), treatments ( 12 ), and the immune response and outcome to co-infecting pathogens ( 13 ).…”

Section: Introductionmentioning

confidence: 99%

Comparative Sensitivity and Specificity of the 7SL sRNA Diagnostic Test for Animal Trypanosomiasis

et al. 2022

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Animal trypanosomiasis (AT) is a significant livestock disease, affecting millions of animals across Sub-Saharan Africa, Central and South America, and Asia, and is caused by the protozoan parasites Trypanosoma brucei, Trypanosoma vivax, and Trypanosoma congolense, with the largest economic impact in cattle. There is over-reliance on presumptive chemotherapy due to inadequate existing diagnostic tests, highlighting the need for improved AT diagnostics. A small RNA species, the 7SL sRNA, is excreted/secreted by trypanosomes in infected animals, and has been previously shown to reliably diagnose active infection. We sought to explore key properties of 7SL sRNA RT-qPCR assays; namely, assessing the potential for cross-reaction with the widespread and benign Trypanosoma theileri, directly comparing assay performance against currently available diagnostic methods, quantitatively assessing specificity and sensitivity, and assessing the rate of decay of 7SL sRNA post-treatment. Results showed that the 7SL sRNA RT-qPCR assays specific for T. brucei, T. vivax, and T. congolense performed better than microscopy and DNA PCR in detecting infection. The 7SL sRNA signal was undetectable or significantly reduced by 96-h post treatment; at 1 × curative dose there was no detectable signal in 5/5 cattle infected with T. congolense, and in 3/5 cattle infected with T. vivax, with the signal being reduced 14,630-fold in the remaining two T. vivax cattle. Additionally, the assays did not cross-react with T. theileri. Finally, by using a large panel of validated infected and uninfected samples, the species-specific assays are shown to be highly sensitive and specific by receiver operating characteristic (ROC) analysis, with 100% sensitivity (95% CI, 96.44–100%) and 100% specificity (95% CI, 96.53–100%), 96.73% (95% CI, 95.54–99.96%) and 99.19% specificity (95% CI, 92.58–99.60%), and 93.42% (95% CI, 85.51–97.16% %) and 82.43% specificity (95% CI, 72.23–89.44% %) for the T brucei, T. congolense and T. vivax assays, respectively, under the conditions used. These findings indicate that the 7SL sRNA has many attributes that would be required for a potential diagnostic marker of AT: no cross-reaction with T. theileri, high specificity and sensitivity, early infection detection, continued signal even in the absence of detectable parasitaemia in blood, and clear discrimination between infected and treated animals.

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Section: Introductionmentioning

confidence: 99%

Comparative Sensitivity and Specificity of the 7SL sRNA Diagnostic Test for Animal Trypanosomiasis

et al. 2022

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“…Nevertheless, due to the more complex procedures and higher costs associated with molecular techniques, several studies in Brazil have explored infections by Babesia spp. and A. marginale using direct diagnosis through blood smears and/or hematocrit, the latter serving as a complementary method to indirectly assess the impact on animal health (R. S. Souza et al, 2021;Bastos et al, 2021;Lopes et al, 2021;Heller et al, 2022;Teixeira et al, 2022).…”

Section: Seminamentioning

confidence: 99%

Revisão sistemática sobre diagnóstico molecular da tristeza parasitária bovina no Brasil: ocorrência e oportunidades futuras

Rahal,

Martins,

Feijó

et al. 2024

Sem. Ci. Agr.

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A bovinocultura brasileira enfrenta diversos desafios, dentre esses, as doenças transmitidas por vetores que geram prejuízos significativos pela ampla disseminação no país. As técnicas moleculares são mais sensíveis na identificação de animais persistentemente infectados. Dessa forma, o objetivo deste trabalho foi compilar dados referentes à ocorrência de Anaplasma marginale, Babesia bigemina e Babesia bovis, causadores da tristeza parasitária bovina (TPB), detectados por técnicas moleculares, identificando lacunas e oportunidades para futuras pesquisas no Brasil. Para isso, foi conduzida uma revisão sistemática, onde os principais critérios de inclusão foram: estudos realizados com amostras do Brasil; utilização de amostras de bovinos naturalmente infectados; dados exatos sobre número ou percentual de animais positivos; número de amostras por rebanho ≥ 10; e informações, pelo menos, do estado de origem das amostras. Ao todo, 38 estudos foram incluídos na revisão, utilizando-se de técnicas de PCR convencional (multiplex PCR, PCR, nPCR e snPCR) e PCR quantitativa e semiquantitativa (qPCR e HRM). As faixas de ocorrência para as espécies foram: 35 a 98,78% para A. marginale; 8,19 a 86,25% para B. bigemina; e de 7,32 a 95,47% para B. bovis. Os maiores percentuais de ocorrência de A. marginale e B. bovis foram no estado de RO, e de B. bigemina foi no estado de SP. Apesar da quantidade de dados encontrados, ainda são evidentes inúmeras oportunidades de direcionamento para futuras pesquisas, principalmente no que diz respeito ao uso de técnicas moleculares e quantificação das perdas nos rebanhos de maior ocorrência da TPB.

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Evaluation of mechanical transmission of Trypanosoma vivax by Stomoxys calcitrans in a region without a cyclic vector

Heller,

Bastos,

Zapa

et al. 2024

Parasitol Res

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Delayed reduction of Anaplasma marginale parasitemia and packed cell volume normalization despite prolonged enrofloxacin treatment of cattle co-infected with Trypanosoma vivax

Cited by 6 publications

References 18 publications

Comparative Sensitivity and Specificity of the 7SL sRNA Diagnostic Test for Animal Trypanosomiasis

Comparative Sensitivity and Specificity of the 7SL sRNA Diagnostic Test for Animal Trypanosomiasis

Revisão sistemática sobre diagnóstico molecular da tristeza parasitária bovina no Brasil: ocorrência e oportunidades futuras

Evaluation of mechanical transmission of Trypanosoma vivax by Stomoxys calcitrans in a region without a cyclic vector

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