Serologically silent, occult equine infectious anemia virus (EIAV) infections in horses

Ricotti, Sonia; García, María I. Rodríguez; Veaute, Carolina; Bailat, A.; Lucca, E.; Cook, R. Frank; Cook, Sheila J.; Soutullo, Adriana R.

doi:10.1016/j.jevs.2016.02.078

Cited by 3 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…PCR‐based tests could supplement existing EIA control efforts worldwide because unlike indirect serological diagnostic techniques they have the potential to identify recently infected equids that represent a significant transmission risk because of high viraemia titers. Furthermore, such techniques are essential to confirming and establishing the prevalence of serologically silent EIAV infections particularly in countries where the virus is endemic . Results from this study demonstrate that in cases of limited economic resources or for use in remote rural regions the EIAV RT‐iiPCR/POCKIT TM plus taco TM mini automatic nucleic acid extraction system is better suited to this type of supplemental diagnostic role because in addition to having equivalent test sensitivity and specificity to conventional EIAV RT‐qPCR it requires lower capital investment, minimal personnel training and can be deployed under field conditions.…”

Section: Discussionmentioning

confidence: 97%

“…Clearly this illustrates the need for direct methods of detection for this equine lentivirus. A need that may become even more pressing if examples of equids that produce positive reactions in PCR‐based tests using virus‐specific oligonucleotide primers but lack detectable antibodies against EIAV (‘serologically silent’) are found to be widespread in countries where the infection is endemic. As there is no practical conventional virus isolation assay for this virus, PCR‐based methods probably represent the most promising diagnostic alternative.…”

Section: Discussionmentioning

confidence: 99%

“…Unfortunately, it is during the period immediately following infection and prior to the development of adaptive immune responses that blood‐associated viral loads may attain their highest levels thereby maximising the risk of transmission . Furthermore, a recent report suggests that EIAV may establish serologically silent infections similar to those observed with woodchuck hepatitis virus (WHV) and simian immunodeficiency virus (SIV) where virus or viral nucleic acids are readily detectable but for reasons that have not been identified, viral replication fails to stimulate detectable humoral responses. Therefore, while the ‘serological window’ defines an urgent need for the development of direct detection techniques against EIAV particularly in cases where recent exposure is suspected, this becomes even more apparent if serologically silent infections with this virus are confirmed as anything than an isolated event.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Rapid detection of equine infectious anaemia virus nucleic acid by insulated isothermal RT‐PCR assay to aid diagnosis under field conditions

Cook

Barrandeguy

Lee

et al. 2018

Equine Veterinary Journal

View full text Add to dashboard Cite

Summary Background Control of equine infectious anaemia (EIA) currently depends on serological diagnosis of infected equids. However, recently infected equids may not produce detectable anti‐EIAV antibodies up to 157 days post infection and so present a high transmission risk. Therefore, direct nucleic acid detection methods are urgently needed to improve EIAV surveillance and management programs in counties where the disease is endemic. Objectives To evaluate a field‐deployable, reverse transcription‐insulated isothermal PCR (RT‐iiPCR) assay targeting the conserved 5′ untranslated region (5′ UTR)/exon 1 of the tat gene of EIAV. Study design The analytical and clinical performance of the newly developed EIAV RT‐iiPCR was evaluated by comparison with a EIAV real‐time RT‐PCR (RT‐qPCR) along with the AGID test. Methods Analytical sensitivity was determined using in vitro transcribed RNA containing the target area of the 5′ UTR/tat gene and samples from two EIAV‐positive horses. Specificity was verified using nine common equine viruses. Clinical performance was evaluated by comparison with EIAV RT‐qPCR and AGID using samples derived from 196 inapparent EIAV carrier horses. Results EIAV RT‐iiPCR did not react with other commonly encountered equine viruses and had equivalent sensitivity (95% detection limit of eight genome equivalents), with a concordance of 95.41% to conventional EIAV RT‐qPCR. However, the RT‐qPCR and RT‐iiPCR had sensitivities of 43.75 and 50.00%, respectively, when compared to the AGID test. Main limitations Low viral loads commonly encountered in inapparent EIAV carriers may limit the diagnostic sensitivity of RT‐PCR‐based tests. Conclusions Although EIAV RT‐iiPCR is not sufficiently sensitive to replace the current AGID test, it can augment control efforts by identifying recently exposed or “serologically silent” equids, particularly as the latter often represent a significant transmission risk because of high viral loads. Furthermore, the relatively low cost and field‐deployable design enable utilisation of EIAV RT‐iiPCR even in remote regions.

show abstract

Section: Discussionmentioning

confidence: 97%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Rapid detection of equine infectious anaemia virus nucleic acid by insulated isothermal RT‐PCR assay to aid diagnosis under field conditions

Cook

Barrandeguy

Lee

et al. 2018

Equine Veterinary Journal

View full text Add to dashboard Cite

show abstract

“…Previous studies have reported that antibodies against capsid p26 protein are produced after glycoproteins antibodies because gp45 is a transmembrane protein and gp90 an integral membrane protein, both more exposed from immune system recognition [30,31]. Despite the rapid and high rate of env gene mutations, as a viral mechanism for evasion of the immune system response, conserved regions in the env sequence have been identified for the diagnostic and production of immunogenic peptides [24,32,33].…”

Section: Discussionmentioning

confidence: 99%

Evaluation of Equine Infectious Anemia Virus by the Indirect Enzyme-linked Immunosorbent Assay EIA-LAB as Screening Tools in Mexico

Domínguez¹,

Jiménez

Vázquez-Chagoyán

et al. 2021

Journal of Equine Veterinary Science

View full text Add to dashboard Cite

Equine infectious anemia is a worldwide distributed disease that affects the Equide family. Commercial effective vaccine is not available, for that reason control of the disease depends on diagnostic tools. To improve the efficiency of the diagnostic program in Cuba, LABIOFAM Group, developed an indirect enzyme-linked immunosorbent assay (ELISA), ELISA kit, to complement the diagnostic system that currently uses the agar gel immunodiffusion (AGID) kit. The ELISA AIE-LAB Kit was evaluated in a Mexican context, compared with the gold standard test Agar gel immunodiffusion, AGID AIE-LABIOFAM, and commercial AGID kit. The analytical sensitivity was determined using serial dilutions twofold of the positive control serum to establish the range of detected antibodies in relation to the cutoff value of the plate (OD 0.300). A precision study was carried out to evaluate repeatability, intermediate precision, and reproducibility by estimating the standard deviation and coefficient of variation. The precision results were satisfactory and the values of the coefficient of variation were considered adequate to guarantee an excellent consistency of the ELISA AIE-LAB. The diagnostic performance of the ELISA AIE-LAB involved the evaluation of specificity, sensitivity, and concordance in comparison with both AGID tests. The diagnostic sensitivity was 100% and the specificity 97.6%, with a very good degree of concordance (Kappa ¼ 0.9). The results suggest that the ELISA AIE-LAB test could be used in Mexico as a diagnostic system for the detection of specific antibodies against the equine infectious anemia virus, as per current international norms.

show abstract

“…A anemia infecciosa equina (AIE) é uma enfermidade causada por um vírus da família Retroviridae e gênero Lentivirus que causa uma infecção persistente em membros da família Equidae (equinos, asininos e muares) em todo mundo, com exceção de determinados locais em que ocorrem técnicas de higiene e que não permitem o desenvolvimento de vetores (Ricotti et al 2016;Gaudaire et al 2018;Wang et al 2018).…”

Section: Introductionunclassified

Anemia Infecciosa Equina na Região Norte do Brasil no Período 2005-2017

Ribeiro¹,

Freiria²

2018

BOLMIRR

View full text Add to dashboard Cite

A anemia infecciosa equina constitui uma das doenças mais relevantes em membros desta espécie devido ao prejuízo aos produtores. A Região Norte possui características climáticas e ambientais propícias para a criação de herbívoros, contudo estas mesmas características também favorecem aos insetos vetores desta enfermidade. O presente trabalho teve como objetivo analisar a quantidade de casos notificados de Anemia Infecciosa Equina na Região Norte do Brasil no período de 2005 a 2017. Os dados foram obtidos do Sistema Nacional de Informação Zoossanitária do Ministério da Agricultura, Pecuária e Abastecimento. Foram constatados 19.239 casos no período estudado, com uma média de 1.480 casos anuais. Não houve uma variação significativa da quantidade anual de casos no período, mas foi observado que os estados com menores rebanhos da região possuíram as maiores proporções em relação ao número de casos/efetivo no ano de 2016. Recomenda-se a adoção de medidas preventivas em relação ao manejo sanitário e controle de vetores e o exame periódico do rebanho como forma de minimizar e controlar o impacto econômico causado por esta enfermidade.

show abstract

Serologically silent, occult equine infectious anemia virus (EIAV) infections in horses

Cited by 3 publications

References 0 publications

Rapid detection of equine infectious anaemia virus nucleic acid by insulated isothermal RT‐PCR assay to aid diagnosis under field conditions

Rapid detection of equine infectious anaemia virus nucleic acid by insulated isothermal RT‐PCR assay to aid diagnosis under field conditions

Evaluation of Equine Infectious Anemia Virus by the Indirect Enzyme-linked Immunosorbent Assay EIA-LAB as Screening Tools in Mexico

Anemia Infecciosa Equina na Região Norte do Brasil no Período 2005-2017

Contact Info

Product

Resources

About