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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.

Objective: Light microscopy which is a blood-based test is the Gold standard for malaria diagnosis in the clinical settings. The low sensitivity of Microscopy coupled with the challenges associated with blood sampling necessitates exploring alternative methods of identifying malaria cases. The aim of this study was to detect the presence of Plasmodium Lactate Dehydrogenase (pLDH) and Plasmodium falciparum Histidine-Rich Protein 2 (PfHRP2) in the saliva of suspected malaria patients and to compare the diagnostic accuracy of these saliva-borne biomarkers with the results of blood film microscopy using Nested PCR as the reference test. Results: Malaria prevalence rates of 51 (27.13%), 80(42.55%), 117 (62.23%) and 95 (50.53%) were detected by the Microscopy, saliva pLDH, saliva PfHRP2 and the PCR respectively. The sensitivity of the saliva PfHRP2 ELISA, 78.95% (95% CI, 69.38-86.64%) and saliva pLDH ELISA, 64.21% (95% CI 53.72 -73.79) was better than the blood film Microscopy and showed moderate agreement with results of the Nested PCR with Kappa co-efficient of 0.5 and 0.44 respectively.