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Real-world data on vaccine-elicited neutralising antibody responses for two-dose AZD1222 in African populations are limited. We assessed baseline SARS-CoV-2 seroprevalence and levels of protective neutralizing antibodies prior to vaccination rollout using binding antibodies analysis coupled with pseudotyped virus neutralisation assays in two cohorts from West Africa: Nigerian healthcare workers (n = 140) and a Ghanaian community cohort (n = 527) pre and post vaccination. We found 44 and 28% of pre-vaccination participants showed IgG anti-N positivity, increasing to 59 and 39% respectively with anti-receptor binding domain (RBD) IgG-specific antibodies. Previous IgG anti-N positivity significantly increased post two-dose neutralizing antibody titres in both populations. Serological evidence of breakthrough infection was observed in 8/49 (16%). Neutralising antibodies were observed to wane in both populations, especially in anti-N negative participants with an observed waning rate of 20% highlighting the need for a combination of additional markers to characterise previous infection. We conclude that AZD1222 is immunogenic in two independent West African cohorts with high background seroprevalence and incidence of breakthrough infection in 2021. Waning titres post second dose indicates the need for booster dosing after AZD1222 in the African setting despite hybrid immunity from previous infection.

The novel coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), continues to remain a global challenge. There is emerging evidence of SARS-CoV-2 virus found in the blood of patients from China and some developed countries. However, there is inadequate data reported in Ghana and other parts of Africa, where blood transfusion service heavily relies on voluntary and replacement blood donors. This study aimed to investigate whether plasma of infected individuals could pose significant transfusion transmitted risk of COVID-19 in Ghanaian populations. This cross-sectional retrospective study was conducted at the Kumasi Centre for Collaborative Research into Tropical Medicine (KCCR), KNUST, Ghana. Study subjects comprised contacts of COVID-19 individuals, those with classical symptoms of COVID-19 and individuals who had recovered based on the new Ghana discharge criteria. Whole blood, sputum or deep coughed saliva samples were collected and transported to KCCR for SARS-CoV-2 testing. Viral nucleic acid was extracted from sputum/nasopharyngeal samples using Da An Gene column based kit and from plasma using LBP nucleic acid extraction kit. Real-Time PCR was performed specifically targeting the ORF1ab and Nucleocapsid (N) genomic regions of the virus. A total of 97 individuals were recruited into the study, with more than half being males (58; 59.7%). The mean age of all subjects was 33 years (SD = 7.7) with minimum being 22 years and maximum 56 years. Majority (76; 78.4%) of all the subjects were asymptomatic, and among the few symptomatic subjects, cough (10; 10.3%) was the most predominant symptom. Of the 97 sputum samples tested, 79 (81.4%) were positive for SARS-CoV-2. We identified SARS-CoV-2 viral RNA in the plasma of 1 (1.03%) subject who had clinically recovered. This study reports the identification of SARS-CoV-2 viral RNA in a convalescent individual in Ghana. Due to the low prevalence observed and the marginal cycling thresholds associated, the risk of transfusion transmission of SARS-CoV-2 is negligible. Well-powered studies and advanced diagnostics to determine infectious viremia is recommended to further evaluate the potential risk of hematogenous transmission among recovered patients.

Background: Several studies have linked coronavirus disease 2019 (COVID-19) risk to age and ABO blood groups. Variations in plasma angiotensin-converting enzyme 2 (ACE2) levels and blood counts have been reported, suggesting an association between disease severity and low lymphocyte levels. Aim: this study aimed to understand how these factors relate to COVID-19 in Ghanaian patients, considering geographical and demographic differences. Methods: Participants were recruited from six hospitals in Kumasi, Ghana, between June 2020 and July 2021. Nasopharyngeal swabs were taken to test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and blood samples were collected for complete blood count testing, ABO/Rhesus typing, and assessment of plasma ACE2 levels. Demographic and COVID-19 severity data were gathered, and IBM SPSS version 25.0 was used for analysis. Results: Overall, 515 patients were enrolled, out of which 55.9% (n = 288/515) were males and 50.3% (n = 259/515) tested positive for SARS-CoV-2. The median age was 37 years (IQR = 26–53). Age was significantly associated with SARS-CoV-2 infection (p = 0.002). The severe COVID-19 group was the oldest (70 years, IQR = 35–80) and presented with anaemia (haemoglobin, g/dL: 9.55, IQR = 7.85–11.93), leukocytosis (WBC × 10³/μL: 15.87, IQR = 6.68–19.80), neutrophilia (NEUT × 10⁶/μL: 14.69, IQR = 5.70–18.96) and lymphocytopenia (LYMPH × 10⁶/μL: 0.47, IQR = 0.22–0.66). No association was found between SARS-CoV-2 positivity and ABO (p = 0.711) or Rh (p = 0.805) blood groups; no association was also found between plasma ACE2 levels and SARS-CoV-2 status (p = 0.079). However, among COVID-19 participants, plasma ACE2 levels were significantly reduced in the moderate illness group (40.68 ng/mL, IQR = 34.09–48.10) compared with the asymptomatic group (50.61 ng/mL, IQR = 43.90–58.61, p = 0.015). Conclusions: While there may be no real association between the ABO blood group, as well as plasma ACE2 levels, and SARS-CoV-2 infection in Ghanaian patients, older individuals are at a higher risk of severe disease. Anaemia, and leukocytosis with lymphocytopenia may be indicators of poor disease progression.

The accurate detection of SARS-CoV-2 through respiratory sampling is critical for the prevention of further transmission and timely initiation of treatment. There is a diverse range of SARS-CoV-2 detection rates in reported studies, with uncertainty regarding the optimal sampling method for COVID-19 diagnosis and monitoring. Oropharyngeal sampling (OPS) is one of the most commonly used methods of respiratory sampling in Ghana and other parts of the world for the detection of SARS-CoV-2 viral RNA. However, this sampling technique has a number of drawbacks, which include difficulty in obtaining high-quality swab samples, increased risk of infection to healthcare workers, and increased cost from a regular supply of swabs, transport media, and personal protective equipment (PPE). This study, therefore, sought to evaluate the diagnostic performance of sputum specimens in the diagnosis of COVID-19. This was a cross-sectional analytical study conducted in two health facilities in Kumasi, Ghana, between April and September 2021. Paired samples (an oropharyngeal swab and sputum) were taken from each recruited patient and run concurrently for the detection of SARS-CoV-2 genes (the N and ORF1ab genes) using RT-qPCR. Of the 317 patients recruited, 50.8% were males, and 60.4% were young adults aged 20–39 years. A significant proportion (65.9%) of the patients did not have any co-morbidity, and the majority were with symptoms; predominantly cough (36.3%), headache (31.5%), general weakness (24.0%), fever (20.2%), and sore throat (16.1%). Being symptomatic (p = 0.003), having comorbidity (p = 0.001), and the reporting facility (p = 0.010) were significantly associated with the COVID-19 status. The sputum samples yielded more COVID-positive, 120/317 (37.9%), as compared to OPS, 83/317 (26.2%). The sputum samples were 85.5% (95% CI, 76.4–91.5) sensitive, 79.1% (95% CI, 73.4–83.7) specific, and with positive and negative predictive values of 59.2% and 93.9%, respectively, when compared with OPS. The overall median of the SARS-CoV-2 viral loads for sputum (3.70 × 10³ copies/mL) were significantly higher than in OPS (1.18 × 10² copies/mL) (p = 0.003). Findings from the study suggest self-collected sputum as a useful alternative to OPS for the diagnosis of COVID-19, providing a comparable diagnostic performance and, thereby, easing the uncomfortable process and mitigating risk of aerosol transmission to healthcare workers.

Candida auris is an emerging multidrug-resistant fungal pathogen that avoids early host immune detection by masking immunostimulatory β-(1,3)-glucan beneath a dense outer mannan layer. Whether caspofungin-induced cell wall remodeling can increase β-(1,3)-glucan exposure and alter innate immune interactions in C. auris remains poorly understood. In this study, we investigate how sublethal concentrations of caspofungin induce cell wall remodeling and modulate innate immune responses. Sublethal caspofungin concentrations were used to maintain normal growth kinetics while allowing cell wall remodeling. Caspofungin treatment increased β-(1,3)-glucan surface exposure across Candida strains, with the strongest response observed in C. auris strain 1100. This increase was supported by fluorescence microscopy, Cy3-positive cell quantification, and ImageJ-based analysis of fluorescence intensity and stained surface area. Scanning electron microscopy showed surface changes consistent with caspofungin-treated cell wall remodeling. Caspofungin-treated Candida cells exhibited enhanced uptake by RAW 264.7 macrophages and increased macrophage-mediated clearance at early and intermediate time points. In C. auris , this increased clearance persisted over 24 h, whereas the effect diminished in C. albicans , consistent with species-specific differences in macrophage interaction and intracellular survival. Finally, in the Galleria mellonella infection model, larvae infected with caspofungin-pretreated cells showed improved survival and reduced fungal burden compared with larvae infected with untreated controls. Together, these findings show that sublethal caspofungin exposure is associated with increased β-(1,3)-glucan exposure, cell wall remodeling, and enhanced innate immune clearance of C. auris . These results support fungal cell wall remodeling as a potential adjunct strategy to improve host-mediated control of multidrug-resistant Candida infections. IMPORTANCE: C. auris is a dangerous fungal pathogen that is difficult to treat and can evade the body’s immune defenses. One reason for its success is its ability to hide key cell wall components that immune cells normally recognize. In this study, we show that low, non-lethal levels of the antifungal drug caspofungin can alter the fungal cell wall in a way that exposes these hidden immune signals. This exposure is associated with improved recognition, engulfment, and killing of C. auris by immune cells. Using imaging, immune cell assays, and an infection model, we show that caspofungin-induced cell wall remodeling is associated with enhanced immune clearance and reduced fungal burden. These findings reveal an additional benefit of echinocandin treatment and suggest that antifungal drugs may help the immune system fight infection, even at doses that do not directly kill the fungus.