6 research outputs found
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
Differential Diffusions of Indinavir and Lopinavir in Genital Secretions of Human Immunodeficiency Virus-Infected Women
Plasma and cervicovaginal secretion (CVS) samples were collected from 19 human immunodeficiency virus type 1-infected women on lopinavir- or indinavir-containing regimens. Lopinavir and indinavir were detectable in 29 and 93% of CVS samples, respectively, a finding that may be ascribed to these drugs' differences in protein binding and pK(a). The relationship between lopinavir and indinavir pharmacodynamics and viral evolution in the female genital tract should be assessed over time
Pathologically confirmed women's breast cancer: A descriptive study of Tunisian and Algerian series
Abstract Background Breast cancer (BC) is the most frequent malignancy among women in Tunisia and Algeria. Clinical and pathological characteristics of this cancer among these populations are not widely reported. The aim of the study was to report clinical and pathological characteristics of women's BC in a Tunisian and Algerian series. Methods Pathologically confirmed 1089 BCs were gathered in the pathology departments of three Northern Tunisian hospitals: Tunis military, Charles Nicolle and Jendouba and in the pathology department of Alger Douera hospital between January 2015 and December 2020. Clinical and pathological findings of the two series: age, tumor size, histological type, grading according to ScarffâBloom Richardson grading system, lymph node status at the time of diagnosis in axillary lymphadenectomy specimens and the immunohistochemical expression of estrogen and progesterone receptors (ER/PR), HER2 and Kiâ67, were collected from the pathological reports. Results The median age at diagnosis was 50 and 48âyears in Tunisian and Algerian series, respectively (pâ=â0.016). The diagnosis of BC was made on surgical specimens (lumpectomy or mastectomy) in 373/491 (76%) cases of the Tunisian series and in 225/598 (37.6%) cases of the Algerian one. Median tumor size was 2.8âcm and 2.5âcm in Algerian and Tunisian series, respectively (pâ=â0.252). Invasive BCs not otherwise specified was observed in 440/481 (91.5%) BCs in Tunisian series and in 519/586 (88.6%) BCs in Algerian series. Axillary lymph node positive tumors were observed in 64.6% and 58.8% of Tunisian and Algerian women, respectively (pâ=â0.926). BCs were ER positive in 311/385 (80.8%) and 486/571 (85.1%) cases and HER2 positive in 86/283 (30.4%) and 60/385 (15.6%) cases of Tunisian and Algerian series, respectively. Conclusions In Tunisia and Algeria, BC has poor prognostic factors with large tumor sizes and high rates of lymph nodes involvement at diagnosis
Reâlocating Moroccan Womenâs identities in a transnational world: the âwoman questionâ in question
The African Network for Improved Diagnostics, Epidemiology and Management of common infectious Agents
Background!#!In sub-Saharan Africa, acute respiratory infections (ARI), acute gastrointestinal infections (GI) and acute febrile disease of unknown cause (AFDUC) have a large disease burden, especially among children, while respective aetiologies often remain unresolved. The need for robust infectious disease surveillance to detect emerging pathogens along with common human pathogens has been highlighted by the ongoing novel coronavirus disease 2019 (COVID-19) pandemic. The African Network for Improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA) is a sentinel surveillance study on the aetiology and clinical characteristics of ARI, GI and AFDUC in sub-Saharan Africa.!##!Methods!#!ANDEMIA includes 12 urban and rural health care facilities in four African countries (CĂŽte d'Ivoire, Burkina Faso, Democratic Republic of the Congo and Republic of South Africa). It was piloted in 2018 in CĂŽte d'Ivoire and the initial phase will run from 2019 to 2021. Case definitions for ARI, GI and AFDUC were established, as well as syndrome-specific sampling algorithms including the collection of blood, naso- and oropharyngeal swabs and stool. Samples are tested using comprehensive diagnostic protocols, ranging from classic bacteriology and antimicrobial resistance screening to multiplex real-time polymerase chain reaction (PCR) systems and High Throughput Sequencing. In March 2020, PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and analysis of full genomic information was included in the study. Standardised questionnaires collect relevant clinical, demographic, socio-economic and behavioural data for epidemiologic analyses. Controls are enrolled over a 12-month period for a nested case-control study. Data will be assessed descriptively and aetiologies will be evaluated using a latent class analysis among cases. Among cases and controls, an integrated analytic approach using logistic regression and Bayesian estimation will be employed to improve the assessment of aetiology and associated risk factors.!##!Discussion!#!ANDEMIA aims to expand our understanding of ARI, GI and AFDUC aetiologies in sub-Saharan Africa using a comprehensive laboratory diagnostics strategy. It will foster early detection of emerging threats and continued monitoring of important common pathogens. The network collaboration will be strengthened and site diagnostic capacities will be reinforced to improve quality management and patient care
A highly virulent variant of HIV-1 circulating in the Netherlands
We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log10 increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence