Search

Numerous tick species are undergoing significant range expansion in Canada, including several Dermacentorspp Koch (Acari: Ixodidae). With the recent description of Dermacentor similisLado in the western United States, additional research is required to determine the current range of this species. Five hundred ninety-eight Dermacentorspp. were collected from companion animals in the western Canadian provinces of British Columbia, Alberta, and Saskatchewan. Ticks were morphologically identified to species, followed by PCR and gel electrophoresis of the ITS-2 partial gene target (n= 595). Ninety-seven percent (n= 579/595) generated valid banding patterns. The banding pattern for the majority (74%, n= 206/278) of Dermacentorspp. from southern British Columbia was consistent with D. variabilis(Say), while 26% (n= 72/278) was consistent with D. andersoniStiles. For samples from Alberta, 38% (n= 3/8) had banding patterns consistent with D. variabilisand 63% (n= 5/8) with D. andersoni. All (n= 293) ticks from Saskatchewan had banding patterns consistent with D. variabilis.After the description of D. similiswas published, DNA sequencing of mitochondrial (16S rDNA gene, COI gene) and nuclear (ITS-2) markers was used to confirm the identity of 40 samples. Twenty-seven samples that had banding patterns consistent with D. variabilisfrom British Columbia were confirmed to be D. similis. One sample from Alberta and five from Saskatchewan were confirmed to be D. variabilisand seven samples from British Columbia were D. andersoni. The ITS-2 amplicons were not useful for differentiating between D. variabilisand D. similis. These results provide evidence of D. similisin western Canada and highlight that sequences of the mitochondrial genes are effective for distinguishing D. andersoni, D. variabilis, and D. similis.

CONTEXTE: Au Canada, on utilise des interventions d'eloignement physique pour ralentir la propagation du SRAS-CoV-2 (coronavirus du syndrome respiratoire aigu severe 2), mais on ignore au juste quelle en sera l'efficacite. Nous avons evalue comment differentes interventions non pharmacologiques pouvaient etre utilisees pour maTtriser la pandemie de COVID-19 (maladie a coronavirus 2019) et alleger le fardeau qu'elle impose au systeme de sante. METHODES: Nous avons utilise un modele a compartiments structure selon l'age pour faire une analyse de la transmission de la COVID-19 dans la population de l'Ontario, au Canada. Nous avons compare un scenario de reference, soit depistage limite, isolement et quarantaine, a des scenarios incluant depistage accru, mesures strictes d'eloignement physique, ou combinaison de depistage accru et d'eloignement physique moins strict. Les interventions etaient appliquees soit pendant des durees fixes, soit selon un cycle dynamique en fonction de l'occupation projetee des lits dans les unites de soins intensifs (USI). Nous presentons les medianes et les intervalles de credibilite tires de 100 experiences repliquees par scenario sur un horizon temporel de 2 ans. RESULTATS: Selon le scenario de reference, nous avons estime que 56 % (intervalle de credibilite de 95 %o, 42 %-63%) de la population ontarienne contractait l'infection pendant l'epidemie. Au moment du sommet epidemique, nous avons projete 107000 (intervalle de credibilite de 95 %, 60 760-149 000) hospitalisations (soins standards) et 55500 (intervalle de credibilite de 95 %, 32 700-75 200) hospitalisations dans les USI. Pour les scenarios a duree fixe, selon les projections, toutes les interventions retardaient et reduisaient la hauteur du sommet epidemique par rapport au scenario de reference, et ce sont les mesures d'eloignement physique strict qui exergaient le plus d'effet; de meme, les interventions de duree plus longue etaient plus efficaces. Selon les projections, les interventions dynamiques reduisaient la proportion de la population atteinte a la fin de la periode de 2 ans et pouvaient ramener le nombre median de cas dans les USI en dega des estimations actuelles de leur capacite en Ontario. INTERPRETATION: Sans eloignement physique substantiel ou une combinaison d'eloignement physique modere et de depistage accru, nous projetons que les ressources des USI pourraient etre insuffisantes. L'eloignement physique dynamique maintiendrait la capacite du systeme de sante en plus de donner un repit psychologique et economique periodique aux populations., La pandemie de COVID-19 (maladie a coronavirus 2019) represente une urgence mondiale de sante publique sans precedent dans l'histoire recente. Depuis le rapport initial de l'Organisation mondiale de la sante [...]

BACKGROUND: Physical-distancing interventions are being used in Canada to slow the spread of severe acute respiratory syndrome coronavirus 2, but it is not clear how effective they will be. We evaluated how different nonpharmaceutical interventions could be used to control the coronavirus disease 2019 (COVID-19) pandemic and reduce the burden on the health care system. METHODS: We used an age-structured compartmental model of COVID-19 transmission in the population of Ontario, Canada. We compared a base case with limited testing, isolation and quarantine to scenarios with the following: enhanced case finding, restrictive physical-distancing measures, or a combination of enhanced case finding and less restrictive physical distancing. Interventions were either implemented for fixed durations or dynamically cycled on and off, based on projected occupancy of intensive care unit (ICU) beds. We present medians and credible intervals from 100 replicates per scenario using a 2-year time horizon. RESULTS: We estimated that 56% (95% credible interval 42%-63%) of the Ontario population would be infected over the course of the epidemic in the base case. At the epidemic peak, we projected 107 000 (95% credible interval 60 760-149 000) cases in hospital (non-ICU) and 55 500 (95% credible interval 32 700-75 200) cases in ICU. For fixed-duration scenarios, all interventions were projected to delay and reduce the height of the epidemic peak relative to the base case, with restrictive physical distancing estimated to have the greatest effect. Longer duration interventions were more effective. Dynamic interventions were projected to reduce the proportion of the population infected at the end of the 2-year period and could reduce the median number of cases in ICU below current estimates of Ontario's ICU capacity. INTERPRETATION: Without substantial physical distancing or a combination of moderate physical distancing with enhanced case finding, we project that ICU resources would be overwhelmed. Dynamic physical distancing could maintain health-system capacity and also allow periodic psychological and economic respite for populations., The coronavirus disease 2019 (COVID-19) pandemic represents a global public health emergency unparalleled in recent time. In the 2 months since the initial World Health Organization report describing the COVID-19 [...]