A survey of patient and public perceptions and awareness of SARS-CoV-2-related risks among participants in India and South Africa (preprint)

A cross-sectional survey was performed among the adult population of participating countries, India and South Africa. The purpose of this study was to explore perceptions and awareness of SARS-CoV-2-related risks in the relevant countries. The main outcome measures were the proportion of participants aware of SARS-CoV-2, and their perception of infection risks. Self-administered questionnaires were used to collect data via a web- and paper-based survey over three months. For data capturing, Microsoft Excel was employed, and descriptive statistics used for presenting data. Pearsons Chi-squared test was used to assess relationships between variables, and a p-value less than 0.05 was considered significant. There were 844 respondents (India: n=660, South Africa: n=184; response rate 87.6%), with a 61.1% vs 38.3% female to male ratio. Post-high-school or university education was the lowest qualification reported by most respondents in India (77.3%) and South Africa (79.3%). Sources of information about the pandemic were usually media and journal publications (73.2%), social media (64.6%), family and friends (47.7%) and government websites (46.2%). Most respondents correctly identified infection prevention measures (such as physical distancing, mask use), with 90.0% reporting improved hand hygiene practices since the pandemic. Hesitancy or refusal to accept the SARS-CoV-2 vaccine was reported among 17.9% and 50.9% of respondents in India and South Africa, respectively. Reasons cited included rushed vaccine development and the futility of vaccines for what respondents considered a self-limiting flu-like illness. Respondents identified public health promotion measures for SARS-CoV-2. Reported hesitancy to the up-take of SARS-CoV-2 vaccines was much higher in South Africa. Vaccination campaigns should consider robust public engagement and contextually fit communication strategies with multimodal, participatory online and offline initiatives to address public concerns, specifically towards vaccines developed for this pandemic and general vaccine hesitancy.

Saliva swabs are the preferred sample for Omicron detection (preprint)

The Omicron variant is characterised by more than 50 distinct mutations, the majority of which are located in the spike protein. The implications of these mutations for disease transmission, tissue tropism and diagnostic testing are still to be determined. We evaluated the relative performance of saliva and mid-turbinate swabs as RT-PCR samples for the Delta and Omicron variants. The positive percent agreement (PPA) of saliva swabs and mid-turbinate swabs to a composite standard was 71% (95% CI: 53-84%) and 100% (95% CI: 89-100%), respectively, for the Delta variant. However, for the Omicron variant saliva and mid-turbinate swabs had a 100% (95% CI: 90-100%) and 86% (95% CI: 71-94%) PPA, respectively. This finding supports ex-vivo data of altered tissue tropism from other labs for the Omicron variant. Reassessment of the diagnostic testing standard-of-care may be required as the Omicron variant becomes the dominant variant worldwide.

Improved performance of saliva for the detection of the B.1.351 variant in South Africa (preprint)

Assessment of the unknown performance of saliva for the detection of the novel SARS-CoV-2 variant of concern (VOC) B.1.351 (501Y.V2) lineage is essential as saliva has been shown to be an equivalent, less invasive and a less costly alternative to nasopharyngeal swabs for the molecular detection of SARS-CoV-2 infection in pre-variant studies. Between 1st August 2020 and 16th January 2021, we enrolled 410 eligible ambulatory participants who presented to Groote Schuur Hospital (GSH) in Cape Town, South Africa for SARS-CoV-2 testing. Of these, 300 were enrolled prior to, and 110 after, the initial detection and replacement of wild-type by the B.1.351 variant. All participants provided a supervised self-collected mid-turbinate (MT) and saliva (SA) swab, in addition to the standard HCW collected NP swab which were all tested by RT-PCR in an accredited diagnostic laboratory. Positive percent agreement to NP swab for SA swabs pre- and post-variant were 51.5% and 72.5% respectively while these values for MT swabs were 75.8% and 77.5%. The negative percent agreement for all swab types during all periods was >98%. The basis for this marked improvement of SA swabs as a diagnostic sample for B.1.351 virus is still being investigated.