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Hepatitis A virus (HAV) causes acute hepatitis in humans worldwide; [approximately equal to] 159 million infections and [approximately equal to] 39,000 deaths were associated with HAV in 2019 (1), despite [...]

Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) has developed substantial antigenic variability. As the majority of the population now has pre-existing immunity due to infection or vaccination, the use of experimentally generated animal immune sera can be valuable for measuring antigenic differences between virus variants. Here, we immunized Syrian hamsters by two successive infections with one of nine SARS-CoV-2 variants. Their sera were titrated against 16 SARS-CoV-2 variants, and the resulting titers were visualized using antigenic cartography. The antigenic map shows a condensed cluster containing all pre-Omicron variants (D614G, Alpha, Delta, Beta, Mu, and an engineered B.1+E484K variant) and considerably more diversity among a selected panel of Omicron subvariants (BA.1, BA.2, BA.4/BA.5, the BA.5 descendants BF.7 and BQ.1.18, the BA.2.75 descendant BN.1.3.1, the BA.2-derived recombinants XBB.2 and EG.5.1, and the BA.2.86 descendant JN.1). Some Omicron subvariants were as antigenically distinct from each other as the wildtype is from the Omicron BA.1 variant. Compared to titers measured in human sera, titers in hamster sera are of higher magnitude, show less fold change, and result in a more compact antigenic map topology. The results highlight the potential of sera from hamsters for the continued antigenic characterization of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Objective To examine the diagnostic performance of real-time reverse transcription (RT)-polymerase chain reaction (PCR) assays for Zika virus detection. Methods We compared seven published real-time RT-PCR assays and two new assays that we have developed. To determine the analytical sensitivity of each assay, we constructed a synthetic universal control ribonucleic acid (uncRNA) containing all of the assays' target regions on one RNA strand and spiked human blood or urine with known quantities of African or Asian Zika virus strains. Viral loads in 33 samples from Zika virus-infected patients were determined by using one of the new assays. Findings Oligonucleotides of the published real-time RT-PCR assays, showed up to 10 potential mismatches with the Asian lineage causing the current outbreak, compared with 0 to 4 mismatches for the new assays. The 95% lower detection limit of the seven most sensitive assays ranged from 2.1 to 12.1 uncRNA copies/reaction. Two assays had lower sensitivities of 17.0 and 1373.3 uncRNA copies/reaction and showed a similar sensitivity when using spiked samples. The mean viral loads in samples from Zika virus-infected patients were 5 x 104 RNA copies/mL of blood and 2 x [10.sup.4] RNA coples/mL of urine. Conclusion We provide reagents and updated protocols for Zika virus detection suitable for the current outbreak strains. Some published assays might be unsuitable for Zika virus detection, due to the limited sensitivity and potential incompatibility with some strains. Viral concentrations in the clinical samples were close to the technical detection limit, suggesting that the use of insensitive assays will cause false-negative results. Objectif Etudier la performance diagnostique des tests bases sur l'amplification en chaine par polymerase (PCR) en temps reel apres transcription inverse (RT) pour detecter le virus Zika. Methodes Nous avons compare sept tests publies utilisant la RT-PCR en temps reel et deux nouveaux tests developpes par nos soins. Afin de determiner la sensibilite analytique de chaque test, nous avons concu un acide ribonucleique synthetique de controle universel (ARNcun) contenant toutes les regions ciblees par les tests sur une helice ARN et enrichi de l'urine ou du sang humain de quantites connues de souches africaines ou asiatiques du virus Zika. Les charges virales dans 33 echantillons provenant de patients infectes par le virus Zika ont ete determinees a l'aide de l'un des nouveaux tests. Resultats Les oligonucleotides des tests publies utilisant la RT-PCR en temps reel ont presente jusqu'a TOmauvais apparlements potentiels avec la lignee asiatique provoquant l'epidemie actuelle, alors qu'on a constate de 0 a 4 mauvais appariements dans le cas des nouveaux tests. La limite de detection inferieure a 95% des sept tests les plus sensibles variait de 2,1 a 12,1 copies dARNcun/reaction. Deux tests presentaient des sensibilites plus basses de 17,0 et 1373,3 copies d'ARNcun/reaction et montraient une sensibilite similaire lorsque des echantillons enrichis etaient utilises. Les charges virales moyennes dans les echantillons provenant de patients infectes par le virus Zika etaient de 5 x 104 copies d'ARN/mL de sang et de 2 x 104 copies dARN/mL d'urine. Conclusion Nous proposons pour detecter le virus Zika des reactifs et des protocoles actualises, adaptes aux souches responsables de la flambee actuelle.Tous les tests publies ne permettent pas de detecter le virus Zika en raison d'une sensibilite limitee et d'une incompatibilite potentielle avec certaines souches. Les concentrations virales dans les echantillons cliniques etaient proches de la limite de detection technique, ce qui laisse penser que l'utilisation de tests insensibles donnera des resultats faussement negatifs. Objetivo Examinar el rendimiento del diagnostico de las pruebas de reaccion en cadena de la polimerasa de transcriptasa inversa (RT-PCR) en tiempo real para la deteccion del virus de Zika. Metodos Se compararon siete pruebas de RT-PCR en tiempo real publicadas y dos pruebas nuevas que se han desarrollado. Con el fin de determinar la sensibilidad analitica de cada prueba, se construyo un acido ribonucleico sintetico de control universal (uncRNA) que contenia todas las regiones objetivo de las pruebas en una hebra de RNA y se anadio a sangre u orina humana con cantidades conocidas de cepas de virus de Zika de Asia o Africa. Se determinaron las cargas viricas en 33 muestras procedentes de pacientes infectados por el virus de Zika a traves de una de las pruebas nuevas. Resultados Los oligonucleotidos de las pruebas de RT-PCR en tiempo real publicadas mostraron hasta 10 posibles discordancias con el linaje de Asia causante de los brotes actuales, en comparacion con 0 de 4 discordancias en el caso de las pruebas nuevas. El limite de deteccion inferior del 95% de las siete pruebas mas sensibles abarco de 2,1 a 12,1 copias/reaccion de uncRNA. Dos pruebas mostraron sensibilidades inferiores de 17,0 y 1373,3 copias/reaccion de uncRNA y presentaron una sensibilidad similar al usar muestras Infectadas. Las cargas viricas medias en las muestras procedentes de pacientes infectados por el virus de Zika fueron de 5 x 104 copias de RNA/mL de sangre y de 2 x [10.sup.4] coplas de RNA/ml de orina. Conclusion Se proporcionan reactivos y protocolos actualizados para la deteccion adecuada del virus de Zika en el caso de las cepas de brotes actuales. Algunas pruebas publicadas pueden no ser adecuadas para la deteccion del virus de Zika, debido a la limitada sensibilidad y a la posible incompatibilidad con algunas cepas. Las concentraciones viricas en las muestras clinicas se acercaron al limite de deteccion tecnico, lo que sugeria que el uso de pruebas Intensivas causaria resultados falsos negativos., Introduction The Zika virus is a mosquito-borne flavivirus with an approximately 11 kilobase ribonucleic acid (RNA) genome. (1) The virus usually causes a mild infection in adults, symptoms include fever, [...]

Dog‐mediated rabies is responsible for approximately 60,000 human deaths annually worldwide. Although dog slaughter for human consumption and its potential risk for rabies transmission has been reported, mainly in some parts of Western Africa and South‐East Asia, more information on this and factors that influence dog meat consumption is required for a better understanding from places like Ghana where the practice is common. We tested 144 brain tissues from apparently healthy dogs slaughtered for human consumption for the presence of rabies viruses using a Lyssavirus‐specific real‐Time RT‐PCR. Positive samples were confirmed by virus genome sequencing. We also administered questionnaires to 541 dog owners from three regions in Ghana and evaluated factors that could influence dog meat consumption. We interacted with butchers and observed slaughtering and meat preparation procedures. Three out of 144 (2.1%) brain tissues from apparently healthy dogs tested positive for rabies virus RNA. Two of the viruses with complete genomes were distinct from one another, but both belonged to the Africa 2 lineage. The third virus with a partial genome fragment had high sequence identity to the other two and also belonged to the Africa 2 lineage. Almost half of the study participants practiced dog consumption [49% (265/541)]. Males were almost twice (cOR = 1.72, 95% CI (1.17–2.52), p‐value =.006) as likely to consume dog meat compared to females. Likewise, the Frafra tribe from northern Ghana [cOR = 825.1, 95% CI (185.3–3672.9), p‐value <.0001] and those with non‐specific tribes [cOR = 47.05, 95% CI (10.18–217.41), p‐value <.0001] presented with higher odds of dog consumption compared to Ewes. The butchers used bare hands in meat preparation. This study demonstrates the presence of rabies virus RNA in apparently healthy dogs slaughtered for human consumption in Ghana and suggests a potential risk for rabies transmission. Veterinary departments and local assemblies are recommended to monitor and regulate this practice. [ABSTRACT FROM AUTHOR]