Epidemiological situation of SARS-CoV-2 infection in Douala, the most populated and highly heterogeneous town of Cameroon: a post-vaccination update

A complex fuzzy decision model for analysing the post-pandemic immuno-sustainability

The post-effects of the COronaVIrus Disease (COVID-19) vary depending on socioeconomic and biological factors. Similarly, the effects of vaccination on people's immunity vary across several factors. After the pandemic, real-life post-vaccination anomalies significantly impact women's health, access to medical treatments and medications, mental well-being, and daily physical activities. However, there has been scant investigation into the physical, psychological, social, and economic ramifications of vaccine effects on women in the post-pandemic era. Therefore, conducting a comprehensive risk assessment is crucial to safeguard women from the post-vaccination effects.To address this issue, the research encompasses complex bipolar spherical fuzzy ℵ-soft set, which has two-sided periodic ambiguous data due to its parametric properties as an adaptable ℵ-soft set and distinguishing criteria as a complex bipolar spherical fuzzy set. In addition, some fundamental operations and properties are presented in a complex bipolar spherical fuzzy ℵ-soft environment. Furthermore, the robust assessment of a real-world application demonstrate the efficacy of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach to optimise the decision result. Finally, the provided decision-making approach is compared with existing techniques to illustrate their remarkable credibility and integrity.

Exploring demographical, clinical, and dietary determinants of vitamin D deficiency among adults in Douala, Cameroon during the COVID-19 era

Background and aim

Vitamin D deficiency (VDD) is a global public health problem in African populations. This study aimed at determining the prevalence, characteristics, and determinants of VDD in the era of SARS-CoV-2/COVID-19. This study was conducted from January to September 2022 in seven health facilities in Douala, Cameroon.

Methods

A structured, pre-tested questionnaire was administered to each participant to collect participants' information. Molecular detection of the SARS-CoV-2 genome was done. A serum level of 25-hydroxyvitamin D < 20 ng/mL was used to diagnose VDD.

Results

A total of 420 participants were included in the study. A Serum levels of 25(OH) vitamin D were reduced in SARS-CoV-2 (+) patients as compared to SARS-CoV-2 (-) patients (21.69 ± 5.64 ng/mL vs 42.09 ± 20.03 ng/mL, p < 0.0001). The overall prevalence of VDD was 10.2 %. SARS-CoV-2 (+) individuals had nearly two times more risk of being VDD compared to SARS-CoV-2 (-) individuals (aRR = 1.81, p < 0.0001). The risk of VDD was reduced by 46 % and 71 % in those consuming cocoa bean or powder regularly (aRR = 0.54, p = 0.03) and rarely (aRR = 0.29, p = 0.02) as compared to those never consuming it. Likewise, the risk of VDD was reduced by 59 % and 78 % in those consuming sardine fish regularly (aRR = 0.47, p = 0.002) and rarely (aRR = 0.22, p = 0.03). Overall, the association between VDD and SARS-CoV-2 infection was consistent, i.e., reduced risk of VDD in SARS-CoV-2 (-) individuals, after stratification for confounding variables.

Conclusion

This study outlined a high burden of VDD, a strong link between VDD and SARS-CoV-2, and suggests the possible utility of vitamin D supplementation for COVID-19 patients in Cameroon.

Serological surveillance reveals a high exposure to SARS-CoV-2 and altered immune response among COVID-19 unvaccinated Cameroonian individuals

Surveillance of COVID-19/SARS-CoV-2 dynamics is crucial to understanding natural history and providing insights into the population's exposure risk and specific susceptibilities. This study investigated the seroprevalence of SARS-CoV-2 antibodies, its predictors, and immunological status among unvaccinated patients in Cameroon. A multicentre cross-sectional study was conducted between January and September 2022 in the town of Douala. Patients were consecutively recruited, and data of interest were collected using a questionnaire. Blood samples were collected to determine Immunoglobin titres (IgM and IgG), interferon gamma (IFN- γ) and interleukin-6 (IL-6) by ELISA, and CD4+ cells by flow cytometry. A total of 342 patients aged 41.5 ± 13.9 years were included. Most participants (75.8%) were asymptomatic. The overall crude prevalence of IgM and IgG was 49.1% and 88.9%, respectively. After adjustment, the seroprevalence values were 51% for IgM and 93% for IgM. Ageusia and anosmia have displayed the highest positive predictive values (90.9% and 82.4%) and specificity (98.9% and 98.3%). The predictors of IgM seropositivity were being diabetic (aOR = 0.23, p = 0.01), frequently seeking healthcare (aOR = 1.97, p = 0.03), and diagnosed with ageusia (aOR = 20.63, p = 0.005), whereas those of IgG seropositivity included health facility (aOR = 0.15, p = 0.01), age of 40-50 years (aOR = 8.78, p = 0.01), married (aOR = 0.21, p = 0.02), fever (aOR = 0.08, p = 0.01), and ageusia (aOR = 0.08, p = 0.01). CD4+, IFN-γ, and IL-6 were impaired in seropositive individuals, with a confounding role of socio-demographic factors or comorbidities. Although the WHO declared the end of COVID-19 as a public health emergency, the findings of this study indicate the need for continuous surveillance to adequately control the disease in Cameroon.

Confounding role of comorbidities and COVID-19 vaccination uptake in clinical utility of hematological biomarkers in Cameroonian patients infected with SARS-CoV-2

Objectives

To analyze variations in blood profile, the extent of hematological disorders, and the impact of comorbidities and COVID-19 vaccination on blood profile parameters and their clinical value for prognostic of SARS-CoV-2 infection.

Methods

This cross-sectional study took place in Douala, Cameroon. A complete blood count and molecular detection of SARS-CoV-2 were performed on patients. Clinical value was appraised using area under the curve (AUC) analysis.

Results

In total, 420 participants were included. A significant reduction of hematological parameters such as lymphocytes (p < 0.0001), red blood cells (P = 0.0025), mean corpuscular hemoglobin count (P < 0.0001), and platelets (P = 0.02) was seen in SARS-CoV-2 (+) patients. Anisocytosis was the main hematological disorder (95.5%). Normocytic normochromic anemia was predominant in SARS-CoV-2 (+) (35.3%) while microcytic normochromic anemia was more frequently seen in SARS-CoV-2 (-) (16.5%). Neutrophil-to-lymphocyte (NLR) consistently showed statistically significant AUC ∼0.75 upon stratification for age, gender, and comorbidities, with the exception of COVID-19 vaccination uptake.

Conclusion

In a context where molecular detection methods are difficultly affordable in health facilities in developing countries such as Cameroon, NLR could be clinically interesting for identifying SARS-CoV-2 infected individuals, especially those with comorbidities.