Clinical evaluation of commercial SARS-CoV-2 serological assays in a malaria endemic setting.

The levels of immune response to SARS-CoV-2 infection or vaccination are poorly understood in African populations and is complicated by cross-reactivity to endemic pathogens as well as differences in host responsiveness. To begin to determine the best approach to minimize false positive antibody levels to SARS-CoV-2 in an African population, we evaluated three commercial assays, namely Bio-Rad Platelia SARS-CoV-2 Total Antibody (Platelia), Quanterix Simoa Semi-Quantitative SARS-CoV-2 IgG Antibody Test (anti-Spike), and the GenScript cPass™ SARS-CoV-2 Neutralization Antibody Detection Kit (cPass) using samples collected in Mali in West Africa prior to the emergence of SARS-CoV-2. A total of one hundred samples were assayed. The samples were categorized in two groups based on the presence or absence of clinical malaria. Overall, thirteen out of one hundred (13/100) samples were false positives with the Bio-Rad Platelia assay and one of the same one hundred (1/100) was a false positive with the anti-Spike IgG Quanterix assay. None of the samples tested with the GenScript cPass assay were positive. False positives were more common in the clinical malaria group, 10/50 (20%) vs. the non-malaria group 3/50 (6%); p = 0.0374 using the Bio-Rad Platelia assay. Association between false positive results and parasitemia by Bio-Rad remained evident, after adjusting for age and sex in multivariate analyses. In summary, the impact of clinical malaria on assay performance appears to depend on the assay and/or antigen being used. A careful evaluation of any given assay in the local context is a prerequisite for reliable serological assessment of anti-SARS-CoV-2 humoral immunity.

Prevalence and Clinical Relevance of Schistosoma mansoni Co-Infection with Mycobacterium tuberculosis: A Systematic Literature Review

Tuberculosis disease stands for the second leading cause of death worldwide after COVID-19, most active tuberculosis cases result from the reactivation of latent TB infection through impairment of immune response. Several factors are known to sustain that process. Schistosoma mansoni, a parasite of the helminth genus that possesses switching power from an immune profile type Th1 to Th2 that favors reactivation of latent TB bacteria. The aim of the study was to assess the prevalence of the co-infection between the two endemic infections. Systematic literature was contacted at the University Clinical Research Center at the University of Sciences, Techniques, and Technologies of Bamako in Mali. Original articles were included, and full texts were reviewed to assess the prevalence and better understand the immunological changes that occur during the co-infection. In total, 3530 original articles were retrieved through database search, 53 were included in the qualitative analysis, and data from 10 were included in the meta-analysis. Prevalence of the co-infection ranged from 4% to 34% in the literature. Most of the articles reported that immunity against infection with helminth parasite and more specifically Schistosoma mansoni infection enhances latent TB reactivation through Th1/Th2. In sum, the impact of Schistosoma mansoni co-infection with Mycobacterium tuberculosis is under-investigated. Understanding the role of this endemic tropical parasite as a contributing factor to TB epidemiology and burden could help integrate its elimination as one of the strategies to achieve the END-TB objectives by the year 2035.

Dynamics of SARS-CoV-2 variants characterized during different COVID-19 waves in Mali.

Background: Emergence of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants may contribute to prolonging the pandemic and increasing morbidity, and mortality related to coronavirus disease 2019 (COVID-19). We describe the dynamics of circulating SARS-CoV-2 variants identified during the different COVID-19 waves that occurred in Mali between April 2021 and October 2021. Methods: We sequenced respiratory SARS-CoV-2 complete spike (S) gene from positive samples. Generated sequences were aligned by Variant Reporter v3.0 using Wuhan-1 strain as a reference. Mutations were noted using the GISAID and Nextclade platforms. Results: Of 16,797 nasopharyngeal swab samples tested, 6.0 % (1008/16,797) were RT-qPCR positive for SARS-CoV-2. Of these, 16.07% (162/1008) had a Ct value ≤ 28 and were amplified and sequenced. We recovered complete S-gene sequence from 80 of 162 [49.8%] samples. We identified seven distinct variants including Delta [62.5%], Alpha [1.2%], Beta [1.2%], Eta [30.0%], 20B [2.5%], 19B and 20A [1.2% each]. Conclusion and perspectives: Our results show the presence of several SARS-CoV-2 variants during COVID-19 waves in Mali between April and October 2021. The continued emergence of new variants highlights the need to strengthen local real-time sequencing capacity, and genomic surveillance for better and coordinated national responses to SARS-CoV-2.

Design of an observational multi-country cohort study to assess immunogenicity of multiple vaccine platforms (InVITE).

In response to the COVID-19 pandemic, COVID-19 vaccines have been developed, and the World Health Oraganization (WHO) has granted emergency use listing to multiple vaccines. Studies of vaccine immunogenicity data from implementing COVID-19 vaccines by national immunization programs in single studies spanning multiple countries and continents are limited but critically needed to answer public health questions on vaccines, such as comparing immune responses to different vaccines and among different populations.

Factors influencing hesitancy towards adult and child COVID-19 vaccines in rural and urban West Africa: a cross-sectional study.

OBJECTIVES: This study aims: (1) to identify and describe similarities and differences in both adult and child COVID-19 vaccine hesitancy, and (2) to examine sociodemographic, perception-related and behavioural factors influencing vaccine hesitancy across five West African countries. DESIGN: Cross-sectional survey carried out between 5 May and 5 June 2021. PARTICIPANTS AND SETTING: 4198 individuals from urban and rural settings in Burkina Faso, Guinea, Mali, Senegal and Sierra Leone participated in the survey. STUDY REGISTRATION: The general protocol is registered on clinicaltrial.gov. RESULTS: Findings show that in West Africa at the time only 53% of all study participants reported to be aware of COVID-19 vaccines, and television (60%, n=1345), radio (56%; n=1258), social media (34%; n=764) and family/friends/neighbours (28%; n=634) being the most important sources of information about COVID-19 vaccines. Adult COVID-19 vaccine acceptance ranges from 60% in Guinea and 50% in Sierra Leone to 11% in Senegal. This is largely congruent with acceptance levels of COVID-19 vaccinations for children. Multivariable regression analysis shows that perceived effectiveness and safety of COVID-19 vaccines increased the willingness to get vaccinated. However, sociodemographic factors, such as sex, rural/urban residence, educational attainment and household composition (living with children and/or elderly), and the other perception parameters were not associated with the willingness to get vaccinated in the multivariable regression model. CONCLUSIONS: Primary sources of information about COVID-19 vaccines include television, radio and social media. Communication strategies addressed at the adult population using mass and social media, which emphasise COVID-19 vaccine effectiveness and safety, could encourage greater acceptance also of COVID-19 child vaccinations in sub-Saharan countries. TRIAL REGISTRATION NUMBER: NCT04912284.

Challenges and difficulties in implementing and adopting isolation and quarantine measures among internally displaced people during the COVID-19 pandemic in Mali (161/250).

Introduction: Isolation and quarantine are among the key measures that protect internally displaced people (IDPs) against COVID-19. This study aims to identify the challenges encountered by humanitarian actors, and health, political, and administrative stakeholders in implementing these measures. It also describes the difficulties faced by IDPs when adopting them, and the local initiatives developed to overcome those difficulties. Method: We conducted a qualitative survey consisting of individual interviews and focus groups among IDPs, humanitarian actors, and health, political, and administrative stakeholders. The data was collected between November and December 2020 in the Bamako and Ségou Regions of Mali. Interviews were recorded with audio recorders, then transcribed and thematically analyzed using the NVivo 13 software. Findings: The study involved 36 individual interviews and eight focus groups with 68 participants of whom IDPs represented 72.3%. The main challenges reported on IDP sites included difficulties in contacting positive cases, a lack of facilities for quarantine and isolation, a lack of physical space for building new facilities, and a lack of financial resources to support IDPs during isolation and quarantine. The difficulties reported included: changes in social behavior and practices, fear of stigma, a poor level of literacy, and language barriers. To address those difficulties, the local initiatives developed by IDPs included strengthening the awareness of IDPs on COVID-19, early warning of sites' leaders about positive and suspected cases, and setting up a toll-free number to facilitate access to appropriate information on COVID-19. Conclusion: The findings of this study could be used as evidence to guide policy, adjust current strategies and take into account with more focus IDPs, a group with increased vulnerability, in COVID-19 response, more precisely during the implementation of isolation and quarantine measures. By doing so, they will help improve the response to COVID-19, IDPs health, and population health.

High SARS-CoV-2 Seroprevalence among Healthcare Workers in Bamako, Mali.

In Mali, a country in West Africa, cumulative confirmed COVID-19 cases and deaths among healthcare workers (HCWs) remain enigmatically low, despite a series of waves, circulation of SARS-CoV-2 variants, the country's weak healthcare system, and a general lack of adherence to public health mitigation measures. The goal of the study was to determine whether exposure is important by assessing the seroprevalence of anti-SARS-CoV-2 IgG antibodies in HCWs. The study was conducted between November 2020 and June 2021. HCWs in the major hospitals where COVID-19 cases were being cared for in the capital city, Bamako, Mali, were recruited. During the study period, vaccinations were not yet available. The ELISA of the IgG against the spike protein was optimized and quantitatively measured. A total of 240 HCWs were enrolled in the study, of which seropositivity was observed in 147 cases (61.8%). A continuous increase in the seropositivity was observed, over time, during the study period, from 50% at the beginning to 70% at the end of the study. HCWs who provided direct care to COVID-19 patients and were potentially highly exposed did not have the highest seropositivity rate. Vulnerable HCWs with comorbidities such as obesity, diabetes, and asthma had even higher seropositivity rates at 77.8%, 75.0%, and 66.7%, respectively. Overall, HCWs had high SARS-CoV-2 seroprevalence, likely reflecting a "herd" immunity level, which could be protective at some degrees. These data suggest that the low number of cases and deaths among HCWs in Mali is not due to a lack of occupational exposure to the virus but rather related to other factors that need to be investigated.

Challenges to the implementation and adoption of physical distancing measures against COVID-19 by internally displaced people in Mali: a qualitative study.

BACKGROUND: For almost a decade now, Mali has been facing a security crisis that led to the displacement of thousands of people within the country. Since March 2020, a health crisis linked to the COVID-19 pandemic also surfaced. To overcome this health crisis, the government implemented some physical distancing measures but their adoption proved difficult, particularly among internally displaced people (IDPs). The objective of this study is to identify the challenges relating to the implementation and adoption of physical distancing measures and to determine the main mitigation measures taken by IDPs to adjust to these new policies. METHODS: An exploratory qualitative research was conducted in Bamako and Ségou, two of the ten regions of Mali. The study counted 68 participants including 50 IDPs, seven administrative and health authorities, and 11 humanitarian actors. Sampling was guided by the principle of saturation and diversification, and data was collected through semi-structured individual interviews (n = 36) and focus groups (n = eight). Analysis was based on thematic content analysis through NVivo software. RESULTS: The main challenges identified concerning the implementation and adoption of physical distancing measures include the proximity in which IDPs live, their beliefs and values, the lack of toilets and safe water on sites, IDPs habits and economic situation, humanitarian actors' lack of financial resources and authority, and social pressure from religious leaders. Implemented mitigation measures include the building of new shelters or their compartmentalization, the creation of income-generating activities and food banks, psychosocial support, promoting awareness of IDPs, and nightly police patrols and surveillance to discourage IDPs from going out. Finally, a call for action is suggested for the actors involved in IDPs support and management. CONCLUSIONS: The study demonstrates the difficulty for IDPs to follow most of the physical distancing measures and informs about the risk of disease spreading among IDPs with its potential consequences. It also shows the inability of mitigation measures to control the outbreak and suggests actions to be considered.

Coordinating the research response to COVID-19: Mali's approach.

Mali, like the rest of the world, has seen a rapid spread of COVID-19 since the first report of imported cases. Despite being a low-income country, Mali has leveraged scientific research resources via coordinated approaches to enable public health emergency planning and response to the COVID-19 pandemic. Mali's approach includes the harmonization of research activities; leveraging of research laboratory capacity of the University Clinical Research Center, Mali International Center for Excellence and three other in-country laboratories for community COVID-19 testing; strengthening relationships amongst local and international stakeholders; and collaboration with the Ministry of Health to integrate scientific evidence into public policy and emergency management of COVID-19 through a platform of consultation and open communication. The country has implemented national coordination of its COVID-19 response by establishing a COVID-19 Scientific Advisory Committee and a COVID-19 Technical Coordination Committee, both within the Ministry of Health and working collaboratively with other stakeholders. Members of Mali's COVID-19 Scientific Advisory Committee also serve as leaders of its principal academic and government clinical and public health research entities. This centralised approach has enabled the prioritisation of COVID-19 control activities, informed allocation of resources, evidence-based public health practices and timely decision-making in the pandemic setting. Though challenges remain, lessons learned from Mali's harnessing of clinical research capacity to guide and support its COVID-19 response can be applied to future global health research challenges and illustrate the power of building public health-responsive research capacity in resource-limited settings through international collaboration.

All Hands on Deck: A synchronized whole-of-world approach for COVID-19 mitigation.

The COVID-19 pandemic can no longer be mitigated by a nationwide approach of individual nations alone. Given its scale and accelerating expansion, COVID-19 requires a coordinated and simultaneous Whole- of-World approach that galvanizes clear global leadership and solidarity from all governments of the world. Considering an 'all hands-on deck' concept, we present a comprehensive list of tools and entities responsible for enabling them, as well a conceptual framework to achieve the maximum impact. The list is drawn from pandemic mitigation tools developed in response to past outbreaks including influenza, coronaviruses, and Ebola, and includes tools to minimize transmission in various settings including person-to-person, crowd, funerals, travel, workplace, and events and gatherings including business, social and religious venues. Included are the roles of individuals, communities, government and other sectors such as school systems, health, institutions, and business. While individuals and communities have significant responsibilities to prevent person-to-person transmission, other entities can play a significant role to enable individuals and communities to make use of the tools. Historic and current data indicate the role of political will, whole-of-government approach, and the role of early introduction of mitigation measures. There is also an urgent need to further elucidate the immunologic mechanisms underlying the epidemiological characteristics such as the low disease burden among women, and the role of COVID-19 in inducing Kawasaki-like syndromes in children. Understanding the role of and development of anti-inflammatory strategies based on our understanding of pro-inflammatory cytokines (IL1, IL-6) is also critical. Similarly, the role of oxygen therapy as an anti-inflammatory strategy is evident and access to oxygen therapy should be prioritized to avoid the aggravation of COVID-19 infection. We highlight the need for global solidarity to share both mitigation commodities and infrastructure between countries. Given the global reach of COVID-19 and potential for repeat waves of outbreaks, we call on all countries and communities to act synergistically and emphasize the need for synchronized pan-global mitigation efforts to minimize everyone's risk, to maximize collaboration, and to commit to shared progress.