A comparison of four epidemic waves of COVID-19 in Malawi; an observational cohort study

Utilizing river and wastewater as a SARS-CoV-2 surveillance tool in settings with limited formal sewage systems

The COVID-19 pandemic has profoundly impacted health systems globally and robust surveillance has been critical for pandemic control, however not all countries can currently sustain community pathogen surveillance programs. Wastewater surveillance has proven valuable in high-income settings, but less is known about the utility of water surveillance of pathogens in low-income countries. Here we show how wastewater surveillance of SAR-CoV-2 can be used to identify temporal changes and help determine circulating variants quickly. In Malawi, a country with limited community-based COVID-19 testing capacity, we explore the utility of rivers and wastewater for SARS-CoV-2 surveillance. From May 2020-May 2022, we collect water from up to 112 river or defunct wastewater treatment plant sites, detecting SARS-CoV-2 in 8.3% of samples. Peak SARS-CoV-2 detection in water samples predate peaks in clinical cases. Sequencing of water samples identified the Beta, Delta, and Omicron variants, with Delta and Omicron detected well in advance of detection in patients. Our work highlights how wastewater can be used to detect emerging waves, identify variants of concern, and provide an early warning system in settings with no formal sewage systems.

Utilizing river and wastewater as a SARS-CoV-2 surveillance tool to predict trends and identify variants of concern in settings with limited formal sewage systems

The COVID-19 pandemic continues to impact health systems globally and robust surveillance is critical for pandemic control, however not all countries can sustain community surveillance programs. Wastewater surveillance has proven valuable in high-income settings, but little is known about how river and informal sewage in low-income countries can be used for environmental surveillance of SARS-CoV-2. In Malawi, a country with limited community-based COVID-19 testing capacity, we explored the utility of rivers and wastewater for SARS-CoV-2 surveillance. From May 2020 - January 2022, we collected water from up to 112 river or informal sewage sites/month, detecting SARS-CoV-2 in 8.3% of samples. Peak SARS-CoV-2 detection in water samples predated peaks in clinical cases. Sequencing of water samples identified the Beta, Delta, and Omicron variants, with Delta and Omicron detected well in advance of detection in patients. Our work highlights wastewater can be used for detecting emerging waves, identifying variants of concern and function as an early warning system in settings with no formal sewage systems.

Mudhune G, M. Morobe J, Said Mohammed K, O. Makori T, Ndwiga L, W. Mburu M, O. Moraa E, Musyoki J, Murunga N, N. Waliaula I, K. Mumelo A, Bejon P, Isabella Ochola-Oyier L, Githinji G, Nokes J, Agoti C. Temporal distribution and clinical characteristics of the Alpha, Delta and Omicron SARS-CoV-2 variants of concern in Laikipia, Kenya: institutional and community-based genomic surveillance

Background: Understanding the molecular epidemiology and clinical presentation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOC) in rural-urban populations in Kenya is important for informing future public health responses and clinical care. Methods: We undertook a retrospective analysis of the clinical presentation and phylogenetic relatedness of specimens from 97 SARS-CoV-2 cases collected between 24th April and 31st December 2021 in Laikipia county, Kenya. VOC were related to observed symptoms. Phylogenetic analyses included contemporaneous sequences from across Kenya and the globe, to contextualise local transmission dynamics. Results: These sequences fell into three VOC; Alpha (n=8), Delta (n=52) and Omicron (n=37). We estimated 75 independent SARS-CoV-2 introductions into the county. The Alpha and Delta VOC were commonly detected in persons aged 31 to 45 years, 50.0% and 30.8%, respectively. The Omicron VOC was mostly detected in 16 to 30-year-olds (51.4%). Whereas relative to the other VOCs, Omicron was associated with mild upper-respiratory tract symptoms (cough, OR 3.78; 95% CI 1.1 – 16.74, p= 0.026) and sore throat, OR 22.42; 95% CI 7.11 – 81.40, p<0.001), Delta was associated with moderate to severe lower-respiratory tract symptoms (shortness of breath, OR 26.8; 95% CI 3.89 – 1158.14, p<0.001) and fever (OR 6.11; 95% CI 1.57 – 35.35, p= 0.004). Post-acute phase neurological complications were suspected in four Delta infected cases (neuralgia, neuritis, peripheral neuropathy, numbness of hand and tinnitus). Conclusion: We highlight the distinctive clinical characteristics of SARS-CoV-2 VOCs, as observed in Laikipia, Kenya, to support evidence-based clinical decisions. Multiple introductions of the VOCs were recorded despite the public health measures that were in place questioning their effectiveness during the study period.

The Impact of Demographic, Clinical Characteristics and the Various COVID-19 Variant Types on All-Cause Mortality: A Case-Series Retrospective Study

(1) Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly evolved into a pandemic affecting virtually every country in the world. We evaluated the demographic, clinical, laboratory, and all-cause mortality of moderate and severe COVID-19 patients admitted to a tertiary care hospital in Oman during the different COVID-19 waves and variant types. (2) Methods: A case-series retrospective study was carried out between 12 March 2020 and 30 June 2022. All adults over the age of 18 with laboratory-confirmed COVID-19 were enrolled. Analyses were performed using univariate and multivariate statistics. (3) Results: A total of 1462 confirmed cases enrolled with the mean age of the cohort was 55 ± 17 years with significant differences among the groups (p = 0.006). A total of 63% and 80% of the patients were males and citizens of Oman, respectively. Patients infected with the Alpha COVID-19 variant type were more likely to have acute respiratory distress syndrome (ARDS) (p < 0.001), stay longer in the hospital (p < 0.001), and get admitted to the intensive care unit (ICU) (p < 0.001). At the same time, those who had the Omicron COVID-19 type were more likely to have renal impairment (p < 0.001) and less likely to be associated with non-invasive ventilation (NIV) (p = 0.001) compared with other COVID-19 variant types. The Delta (adjusted odds ratio (aOR), 1.8; 95% confidence interval (CI): 1.22−2.66; p = 0.003) and Omicron (aOR, 1.88; 95% CI: 1.09−3.22; p = 0.022) COVID-19 variant types were associated with higher all-cause mortality when compared to the initial COVID-19 variant. Old age (aOR, 1.05; 95% CI: 1.04−1.06; p < 0.001), the presence of respiratory disease (aOR, 1.58; 95% CI: 1.02−2.44; p = 0.04), ICU admission (aOR, 3.41; 95% CI: 2.16−5.39; p < 0.001), lower eGFR (aOR, 1.61; 95% CI: 1.17−2.23; p = 0.004), and ARDS (aOR, 5.75; 95% CI: 3.69−8.98; p < 0.001) were also associated with higher mortality while NIV requirements were associated with lower odds of dying (aOR, 0.65; 95% CI: 0.46−0.91; p = 0.012). (4) Conclusions: Alpha and Delta variants were associated with a longer hospital stay, need for intensive care, mechanical ventilation, and increased mortality. Old age, cardiac renal dysfunction were commonly associated with Omicron variants. Large-scale national studies to further assess the risk factors for mortality related to COVID-19 waves are warranted.

Mudhune G, M. Morobe J, Said Mohammed K, O. Makori T, Ndwiga L, W. Mburu M, O. Moraa E, Musyoki J, Murunga N, N. Waliaula I, K. Mumelo A, Bejon P, Isabella Ochola-Oyier L, Githinji G, Nokes J, Agoti C. Temporal distribution and clinical characteristics of the Alpha, Delta and Omicron SARS-CoV-2 variants of concern in Laikipia, Kenya: institutional and community-based genomic surveillance

Background: Understanding the molecular epidemiology and clinical presentation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOC) in rural-urban populations in Kenya is important for informing future public health responses and clinical care. Methods: We undertook a retrospective analysis of the clinical presentation and phylogenetic relatedness of specimens from 97 SARS-CoV-2 cases collected between 24th April and 31st December 2021 in Laikipia county, Kenya. VOC were related to observed symptoms. Phylogenetic analyses included contemporaneous sequences from across Kenya and the globe, to contextualise local transmission dynamics. Results: These sequences fell into three VOC; Alpha (n=8), Delta (n=52) and Omicron (n=37). We estimated 75 independent SARS-CoV-2 introductions into the county. The Alpha and Delta VOC were commonly detected in persons aged 31 to 45 years, 50.0% and 30.8%, respectively. The Omicron VOC was mostly detected in 16 to 30-year-olds (51.4%). Whereas relative to the other VOCs, Omicron was associated with mild upper-respiratory tract symptoms (cough, OR 3.78; 95% CI 1.1 – 16.74, p= 0.026) and sore throat, OR 22.42; 95% CI 7.11 – 81.40, p<0.001), Delta was associated with moderate to severe lower-respiratory tract symptoms (shortness of breath, OR 26.8; 95% CI 3.89 – 1158.14, p<0.001) and fever (OR 6.11; 95% CI 1.57 – 35.35, p= 0.004). Post-acute phase neurological complications were suspected in four Delta infected cases (neuralgia, neuritis, peripheral neuropathy, numbness of hand and tinnitus). Conclusion: We highlight the distinctive clinical characteristics of SARS-CoV-2 VOCs, as observed in Laikipia, Kenya, to support evidence-based clinical decisions. Multiple introductions of the VOCs were recorded despite the public health measures that were in place questioning their effectiveness during the study period.