Retrospective Seroprevalence of Orthopoxvirus Antibodies among Key Populations, Kenya.

We identified a cluster of mpox exposures among key populations in Kenya through retrospective serologic screening. We identified strong seropositivity among sex workers and gay, bisexual, and other men who have sex with men. These findings demonstrate the need for increased mpox surveillance among mpox-endemic and mpox-endemic-adjacent regions in Africa.

Canada's approach to SARS-CoV-2 sero-surveillance: Lessons learned for routine surveillance and future pandemics.

SETTING: In Canada's federated healthcare system, 13 provincial and territorial jurisdictions have independent responsibility to collect data to inform health policies. During the COVID-19 pandemic (2020-2023), national and regional sero-surveys mostly drew upon existing infrastructure to quickly test specimens and collect data but required cross-jurisdiction coordination and communication. INTERVENTION: There were 4 national and 7 regional general population SARS-CoV-2 sero-surveys. Survey methodologies varied by participant selection approaches, assay choices, and reporting structures. We analyzed Canadian pandemic sero-surveillance initiatives to identify key learnings to inform future pandemic planning. OUTCOMES: Over a million samples were tested for SARS-CoV-2 antibodies from 2020 to 2023 but siloed in 11 distinct datasets. Most national sero-surveys had insufficient sample size to estimate regional prevalence; differences in methodology hampered cross-regional comparisons of regional sero-surveys. Only four sero-surveys included questionnaires. Sero-surveys were not directly comparable due to different assays, sampling methodologies, and time-frames. Linkage to health records occurred in three provinces only. Dried blood spots permitted sample collection in remote populations and during stay-at-home orders. IMPLICATIONS: To provide timely, high-quality information for public health decision-making, routine sero-surveillance systems must be adaptable, flexible, and scalable. National capability planning should include consortiums for assay design and validation, defined mechanisms to improve test capacity, base documents for data linkage and material transfer across jurisdictions, and mechanisms for real-time communication of data. Lessons learned will inform incorporation of a robust sero-survey program into routine surveillance with strategic sampling and capacity to adapt and scale rapidly as a part of a comprehensive national pandemic response plan.

RéSUMé: CONTEXTE: Au Canada, où le système de santé est fédéré, les 13 juridictions provinciales et territoriales ont la responsabilité individuelle de recueillir les données qui leur permettent d'élaborer leurs politiques de santé. Lors de la pandémie de COVID-19 (2020­2023), pour réaliser les enquêtes de séroprévalence à l'échelle régionale et nationale, les autorités ont principalement utilisé l'infrastructure existante pour pouvoir analyser les échantillons et recueillir des données rapidement, mais cela a également nécessité de la communication et de la coordination entre les différentes juridictions. INTERVENTION: Au Canada, il y a eu quatre enquêtes nationales et sept enquêtes régionales sur la séroprévalence du SARS-CoV-2 dans la population générale. Les méthodologies utilisées différaient selon la méthode de sélection des participants, le choix des tests d'analyses et les structures de rapports. Nous avons analysé la façon dont ces enquêtes avaient été réalisées afin d'en dégager des éléments essentiels qui permettront de planifier pour les futures pandémies. RéSULTATS: Entre 2020 et 2023, plus d'un million d'échantillons, répartis en 11 ensembles de données distincts, ont été analysés afin de rechercher la présence d'anticorps au SARS-CoV-2. Dans la plupart des enquêtes nationales, la taille de l'échantillon était insuffisante pour pouvoir estimer la prévalence à l'échelle régionale. La disparité des méthodologies utilisées a entravé la comparaison des enquêtes régionales. Seules quatre enquêtes fournissaient les données recueillies à partir des questionnaires. Il a été impossible de comparer les enquêtes entre elles en raison de la diversité des tests d'analyse utilisés, des méthodes d'échantillonnage et de la durée des enquêtes. Seules trois provinces avaient couplé leurs données avec les archives médicales. Pour réaliser les enquêtes dans les populations éloignées et lors des périodes de confinement, la méthode d'analyse sur gouttes de sang séché a été utilisée. CONCLUSION: Afin de pouvoir fournir, en temps et en heure, des données de haute qualité pour la prise de décisions en matière de santé publique, un système de sérosurveillance continuelle doit être adaptable, modulable et évolutif. En cas de pandémie, un plan national doit prévoir des consortiums pour la conception et la validation des tests d'analyse, des moyens d'amélioration de la capacité de dépistage, des documents de base pour le couplage des données, un mode de transfert du matériel entre les différentes juridictions et des moyens pour une communication en temps réel des données. Les leçons tirées de cette analyse permettront de mettre en place un solide programme d'enquêtes de séroprévalence au sein des systèmes de sérosurveillance continuelle, et que ce programme sera accompagné d'une stratégie d'échantillonnage et d'un plan d'intervention national, rapide et complet en cas de pandémie.

A case for implementing an HSV1/2, VZV, and syphilis lesion panel in Manitoba, Canada.

Syphilis, caused by Treponema pallidum subsp. pallidum (TPA), is becoming a significant public health concern, with rising incidence in Manitoba exceeding the national average. The province has also seen a demographic shift leading to women representing 51.9% of cases in 2021, leading to the re-emergence of congenital syphilis. Given the similarities in lesion appearance between TPA and other pathogens such as herpesviruses, accurate diagnosis is crucial for effective management and prevention. In order to address the potential for missed TPA cases, we conducted a quality assurance study from June 2021 to March 2023, screening over 5,000 mucocutaneous lesion swabs for TPA, initially submitted for herpes simplex virus (HSV) and varicella zoster virus (VZV) testing. Positivity rates were 13% for HSV1, 13% for HSV2, 6.7% for VZV, and 6.6% for TPA. Turnaround times (TAT) for TPA testing, as a send-out to the reference laboratory, averaged 17.8 days. Of the TPA-positive specimens, 36% did not have a corresponding TPA PCR test ordered, and 19% did not have accompanying syphilis serology within 30 days of collection. Creation of a multiplex lesion panel identified high sensitivity and specificity for HSV1, HSV2, VZV, and TPA, with robust reproducibility across multiple runs. Incorporation of TPA into a lesion panel improved the TAT to 4 days. Our findings emphasize the need for improved testing strategies to combat the syphilis epidemic and enhance public health outcomes.IMPORTANCESyphilis resurgence has become a significant global public health concern. In particular, the Canadian Prairies have been struggling with high incidence since 2016, exceeding the national Canadian average. We undertook a quality assurance study that highlighted significant gaps in diagnosis of acute syphilis, which led to the development of a highly sensitive and specific multiplex lesion assay for the dual detection of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), varicella zoster virus (VZV), and syphilis.

The descriptive epidemiology of pre-omicron SARS-CoV-2 breakthrough infections and severe outcomes in Manitoba, Canada.

Introduction: Vaccination plays a key role in curbing severe outcomes resulting from COVID-19 disease. With the Omicron variant and the relaxing of public health protections breakthrough infections are increasingly common, and certain groups remain at higher risk for severe outcomes from breakthrough infections. We analysed population-based public health data from Manitoba, Canada to understand characteristics of those experiencing breakthrough infections and severe outcomes from breakthrough infections. Data from previous pandemic stages can provide valuable information regarding severe outcomes associated with breakthrough infection in the Omicron and future phases. Methods: Positive SARS-CoV-2 PCR tests from Cadham Provincial Laboratory were linked to case information from the population-based Public Health Information Management System. A retrospective design was used with time-to-event analyses to examine severe outcomes among those experiencing breakthrough infection. Results: Breakthrough cases were more likely to have 2 + chronic conditions, compared to age-, sex-, and time-period matched unvaccinated cases (24% vs. 17%), with hypertension (30%), diabetes (17%), and asthma (14%) being the most prevalent chronic conditions amongst breakthrough cases. Severe outcomes resulting from breakthrough infection was associated with age and chronic conditions, with those with 2 + chronic conditions at higher risk of severe outcomes (adjusted hazard ratio: 3.6, 95% confidence intervals: 2.0-6.4). Risk of severe outcomes varied by age group, with those 70 + years at over 13 times the risk of severe outcomes (95% CI: 4.5-39.8), compared to those 18-29 years of age. Discussion: Our results demonstrate the impact of chronic conditions on the likelihood of, and severity of outcomes from breakthrough infections. These findings underscore the importance of vaccination programs prioritizing vulnerable populations.