Using Serum Specimens for Real-Time PCR-Based Diagnosis of Human Granulocytic Anaplasmosis, Canada.

Whole blood is the optimal specimen for anaplasmosis diagnosis but might not be available in all cases. We PCR tested serum samples collected in Canada for Anaplasma serology and found 84.8%-95.8% sensitivity and 2.8 average cycle threshold elevation. Serum can be acceptable for detecting Anaplasma spp. when whole blood is unavailable.

Jamestown Canyon and snowshoe hare virus seroprevalence in New Brunswick.

Background: Jamestown Canyon virus (JCV) and snowshoe hare virus (SSHV) are wide-ranging mosquito-borne arboviruses in the California serogroup viruses (CSGV) that are known to circulate in New Brunswick. Despite potential for debilitating central nervous system manifestations, the prevalence of human exposure to these viruses in New Brunswick is unknown. The goal of this study was to quantify rates of human exposure in New Brunswick to these neglected arboviruses. Methods: A retrospective, anonymized provincial serosurvey was performed using a stratified random sample of residual sera submitted between May 2015 and August 2016. To determine the seroprevalence of JCV and SSHV, competitive enzyme-linked immunosorbent assay-positive samples were confirmed positive using plaque-reduction neutralization testing (PRNT). Results: A total of 452 serum samples were screened. The seroprevalence of antibodies against CSGV was estimated to be 31.6% (95% CI 27.4% to 36.1%) with 143 positive samples. PRNT results indicated that most single virus exposures were due to JCV (38 of 143; 26.6%) rather than SSHV (3 of 143; 2.1%). The species of CSGV, to which the remaining 102 seropositive people were exposed, could not be precisely determined. Conclusions: The prevalence of human exposure to CSGV is high but comparable to rates observed in other Atlantic Canadian jurisdictions. Studies such as this provide important baseline epidemiological data regarding the risk of exposure to these neglected arboviruses. SSHV and JCV should be considered in the differential diagnosis for undiagnosed febrile and neuroinvasive illness during mosquito season, particularly when testing for common aetiologies is negative or inconclusive.

Historique : Le virus de Jamestown Canyon (VJC) et le virus du lièvre d'Amérique (VLA) sont des arbovirus à grande portée transmis par des moustiques des virus du sérogroupe Californie (VSGC) qui circulent au Nouveau-Brunswick (NB). Malgré le risque de manifestations débilitantes du système nerveux central, on ne connaît pas la prévalence d'exposition humaine à ces virus au NB. La présente étude visait à quantifier le taux d'exposition humaine à ces arbovirus négligés au NB. Méthodologie : Les chercheurs ont réalisé une enquête sérologique rétrospective provinciale anonymisée au moyen d'un échantillon randomisé stratifié de sérum résiduel soumis entre mai 2015 et août 2016 au dépistage systématique. Ils ont stratifié le processus de sélection selon l'âge, le sexe et la zone de santé régionale afin de garantir un échantillonnage proportionné. Pour déterminer la séroprévalence du VJC et du VLA, ils ont confirmé la positivité des résultats d'échantillons positifs au test ELISA au moyen de tests de séroneutralisation par réduction des plaques (TSRP). Résultats : Au total, 452 échantillons de sérum ont fait l'objet d'un dépistage. Au NB, la séroprévalence des anticorps anti-VSGC était évaluée à 31,6 % (IC à 95 %, 27,4 % à 36,1 %), pour 143 échantillons positifs. Selon les résultats du TSRP, la plupart des expositions à un seul virus étaient causées par le VJC (38 cas sur 143, 26,6 %) plutôt qu'au VLA (trois cas sur 143, 2,1 %). Les espèces de VSGC, auxquelles les 102 autres personnes séropositives ont été exposées, n'ont pas pu être établies avec précision. Conclusions : La prévalence d'exposition humaine au VSGC est élevée, mais comparable aux taux observés dans d'autres régions des provinces de l'Atlantique. Des études comme celle-ci fournissent des données épidémiologiques de référence importantes à l'égard du risque d'exposition humaine à ces arbovirus négligés. Il faut tenir compte du VLA et du VJC dans le diagnostic différentiel de maladie fébrile et neuro-invasive pendant la saison des moustiques, notamment lorsque les tests pour dépister d'autres étiologies courantes sont négatifs ou non concluants.

Vector Competence of Some Mosquito Species From Canada For Zika Virus.

The recent introduction of Zika virus (ZIKV) into the Americas and the occurrence of birth defects associated with infection during pregnancy have created a concern about the spread of this virus into more northern countries in the Americas. Therefore, we examined several species of mosquitoes found in southern Manitoba, Canada, for their susceptibility to infection and their ability to transmit ZIKV. Aedes cinereus, Ae. euedes, Ae. fitchii, Ae. sticticus, Ae. vexans, Coquillettidia perturbans, Culex restuans, and Cx. tarsalis were captured in the vicinity of Winnipeg, Manitoba; brought to the laboratory; and allowed to feed on a ZIKV-sheep blood suspension to determine oral susceptibility. In addition, some of the nonfed individuals were inoculated intrathoracically to examine for the presence of a salivary gland barrier. Despite ingesting blood containing 105.4 plaque-forming units/ml, infection rates were very low, and infected individuals were only detected for Ae. vexans. Transmission was observed for Ae. vexans, Cq. perturbans, and Cx. restuans that had been inoculated with ZIKV, although rates were low. Based on the extremely low vector competence found in this study and the lack of a preferential feeding on humans, it is unlikely than any of the mosquito species tested in this study would be involved in any large-scale transmission of ZIKV in Canada.

Corynebacterium lowii sp. nov. and Corynebacterium oculi sp. nov., derived from human clinical disease and an emended description of Corynebacterium mastitidis.

Strains of members of the genus Corynebacterium derived from ophthalmologic patients in Japan, Belgium and Switzerland and found to be closely related to-, but distinguishable from Corynebacterium mastitidis by 16S rRNA gene sequencing, were characterized using biochemical, chemotaxonomic, MALDI-TOF mass spectrometry and antimicrobial susceptibility methods and DNA-DNA hybridization as well as by whole-genome sequencing (WGS). Based on this investigation, we describe Corynebacterium lowii sp. nov. and Corynebacterium oculi sp. nov., derived from human ocular specimens, as well as emend the description of Corynebacterium mastitidis. Type strains for these species are: C. lowii R-50085T (=LMG 28276T =CCUG 65815T) and C. oculi R-50187T (=LMG 28277T =CCUG 65816T). DNA G+C content was found to be 62.2 % (by HPLC) and 62.8 % (by WGS) for C. lowii R-50085T, 64.1 % (HPLC) and 64.8 % (WGS) for C. oculi R-50187T and 67.8 % (HPLC) for C. mastitidis LMG 19040T [=S-8T =CCUG 38654T =CECT 4843T =CIP 105509T =DSM 44356T =IFO (NBRC)16160T =JCM 12269T].