8 research outputs found
Multilevel analysis of childhood nonviral gastroenteritis associated with environmental risk factors in Quebec, 1999â2006
Childhood nonviral gastroenteritis is a priority for various public health authorities. Given that waterborne transmission is sometimes incriminated during investigation of gastroenteritis outbreaks, the authors hypothesized that watershed characteristics may influence the occurrence of this disease and could contribute additional insights for better prevention and control. The study described here aimed to investigate watershed characteristics in relation to nonviral gastroenteritis and specifically three bacterial and parasitic forms of childhood gastroenteritis to assess their relative importance in the province of Quebec, Canada. Information on children aged 0â4 years with bacterial or parasitic enteric infections reported through ongoing surveillance between 1999 and 2006 in the province of Quebec was collected. Factors measured at the municipal and watershed levels were analyzed using multilevel models with a Poisson distribution and log link function. Childhood nonviral gastroenteritis, giardiasis, and campylobacteriosis were positively associated with small ruminants and cattle density. Childhood salmonellosis was positively associated with cattle density. Also, childhood campylobacteriosis incidence
was positively associated with larger watershed agricultural surface. In addition to local agroenvironmental factors, this analysis revealed an important watershed effect
Managing water infrastructure and equitable land compensation schemes in irrigation projects for social and environmental benefits.
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance
INTRODUCTION
Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic.
RATIONALE
We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs).
RESULTS
Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants.
CONCLUSION
Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
A descriptive review of selected nonviral enteric illnesses reported in children in Quebec between 1999 and 2006
OBJECTIVE: To review the epidemiology of selected nonviral enteric illnesses reported in children in Quebec between 1999 and 2006
Réponses Physiologiques et Biochimiques au Déficit Hydrique Du Soja (Glycine Max (L.) Merrill) Inoculé par Bradyrhizobium Japonicum
RĂ©sumĂ©Une Ă©tude de lâeffet dâun dĂ©ficit hydrique par interruption dâarrosage dâeau sur les paramĂštres physiologiques et biochimiques dâune variĂ©tĂ© de soja (Glycine max (L.) Merrill) inoculĂ©e par la bactĂ©rie du sol Bradyrhizobium japonicum, a Ă©tĂ© rĂ©alisĂ©e. Les rĂ©sultats obtenus montrent que le dĂ©ficit hydrique entraine aux stades vĂ©gĂ©tatif et de floraison, une baisse de la teneur relative en eau, des potentiels hydriques foliaires de base et minimal et une Ă©lĂ©vation des teneurs en proline, en sucres solubles et en protĂ©ines totales foliaires. Les teneurs en chlorophylles a, b et totales ont eu une Ă©lĂ©vation significative au stade vĂ©gĂ©tatif, sous lâeffet du dĂ©ficit hydrique. Lâinoculation a augmentĂ© significativement le potentiel hydrique minimal chez les plantes stressĂ©es au stade floraison, ainsi que le nombre de gousses et de graines aux deux stades chez les tĂ©moins. De plus, elle a attĂ©nuĂ© lâaccumulation de proline et de sucres solubles chez les plantes stressĂ©es au stade vĂ©gĂ©tatif. Par contre, lâinoculation a amĂ©liorĂ© lâaccumulation de proline et de sucres solubles au stade floraison. Cette Ă©tude a  montrĂ© que le soja tolĂšre mieux le stress hydrique aux niveaux physiologique et biochimique, lorsquâil est prĂ©alablement inoculĂ© avec Brayrhizobium japonicum
Baseline Meningococcal Carriage in Burkina Faso before the Introduction of a Meningococcal Serogroup A Conjugate Vaccineâż
The serogroup A meningococcal conjugate vaccine MenAfriVac has the potential to confer herd immunity by reducing carriage prevalence of epidemic strains. To better understand this phenomenon, we initiated a meningococcal carriage study to determine the baseline carriage rate and serogroup distribution before vaccine introduction in the 1- to 29-year old population in Burkina Faso, the group chosen for the first introduction of the vaccine. A multiple cross-sectional carriage study was conducted in one urban and two rural districts in Burkina Faso in 2009. Every 3 months, oropharyngeal samples were collected from >5,000 randomly selected individuals within a 4-week period. Isolation and identification of the meningococci from 20,326 samples were performed by national laboratories in Burkina Faso. Confirmation and further strain characterization, including genogrouping, multilocus sequence typing, and porA-fetA sequencing, were performed in Norway. The overall carriage prevalence for meningococci was 3.98%; the highest prevalence was among the 15- to 19-year-olds for males and among the 10- to 14-year-olds for females. Serogroup Y dominated (2.28%), followed by serogroups X (0.44%), A (0.39%), and W135 (0.34%). Carriage prevalence was the highest in the rural districts and in the dry season, but serogroup distribution also varied by district. A total of 29 sequence types (STs) and 51 porA-fetA combinations were identified. The dominant clone was serogroup Y, ST-4375, P1.5-1,2-2/F5-8, belonging to the ST-23 complex (47%). All serogroup A isolates were ST-2859 of the ST-5 complex with P1.20,9/F3-1. This study forms a solid basis for evaluating the impact of MenAfriVac introduction on serogroup A carriage