Using Wastewater Surveillance to Compare COVID-19 Outbreaks during the Easter Holidays over a 2-Year Period in Cape Town, South Africa

• Published in: Viruses Vol. 15; no. 1; p. 162
• Main Authors: Mahlangeni, Nomfundo, Street, Renée, Horn, Suranie, Mathee, Angela, Mangwana, Noluxabiso, Dias, Stephanie, Sharma, Jyoti Rajan, Ramharack, Pritika, Louw, Johan, Reddy, Tarylee, Surujlal-Naicker, Swastika, Nkambule, Sizwe, Webster, Candice, Mdhluli, Mongezi, Gray, Glenda, Muller, Christo, Johnson, Rabia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 05-01-2023; MDPI
• Subjects: Coronaviruses; COVID-19; COVID-19 - epidemiology; Disease transmission; Easter holidays; Epidemiology; Genomes; Holidays; Holidays & special occasions; Humans; Laboratories; Outbreaks; Ribonucleic acid; RNA; RNA, Viral - genetics; SARS-CoV-2; SARS-CoV-2 - genetics; Severe acute respiratory syndrome coronavirus 2; South Africa - epidemiology; Statistical analysis; Tourism; Travel; Trends; Wastewater; wastewater surveillance; Wastewater treatment; wastewater treatment plants; Wastewater-Based Epidemiological Monitoring; Water treatment; South Africa; United States > US; Cape Town South Africa; SARS-CoV-2; wastewater treatment plants; Easter holidays; wastewater surveillance
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v15010162

Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown to be an important approach to determine early outbreaks of infections. Wastewater-based epidemiology (WBE) is regarded as a complementary tool for monitoring SARS-CoV-2 trends in communities. In this study, the changes in the SARS-CoV-2 RNA levels in wastewater during Easter holidays in 2021 and 2022 in the City of Cape Town were monitored over nine weeks. Our findings showed a statistically significant difference in the SARS-CoV-2 RNA viral load between the study weeks over the Easter period in 2021 and 2022, except for study week 1 and 4. During the Easter week, 52% of the wastewater treatment plants moved from the lower (low viral RNA) category in 2021 to the higher (medium to very high viral RNA) categories in 2022. As a result, the median SARS-CoV-2 viral loads where higher during the Easter week in 2022 than Easter week in 2021 (p = 0.0052). Mixed-effects model showed an association between the SARS-CoV-2 RNA viral loads and Easter week over the Easter period in 2021 only (p < 0.01). The study highlights the potential of WBE to track outbreaks during the holiday period.