Wastewater-Based Epidemiology as a Tool to Detect SARS-CoV-2 Circulation at the Community Level: Findings from a One-Year Wastewater Investigation Conducted in Sicily, Italy
Carmelo Massimo Maida,
Fabio Tramuto,
Giovanni Maurizio Giammanco,
Roberta Palermo,
Walter Priano,
Simona De Grazia,
Giuseppa Purpari,
Giuseppina La Rosa,
Elisabetta Suffredini,
Luca Lucentini,
Mario Palermo,
Walter Pollina Addario,
Giorgio Graziano,
Palmira Immordino,
Francesco Vitale,
SARI Collaboration Group,
Walter Mazzucco
Affiliations
Carmelo Massimo Maida
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Fabio Tramuto
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Giovanni Maurizio Giammanco
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Roberta Palermo
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Walter Priano
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Simona De Grazia
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Giuseppa Purpari
Istituto Zooprofilattico Sperimentale della Sicilia “A. Mirri”, Via Marinuzzi, 90129 Palermo, Italy
Giuseppina La Rosa
Istituto Superiore di Sanità (ISS), Viale Regina Elena 299, 00161 Rome, Italy
Elisabetta Suffredini
Istituto Superiore di Sanità (ISS), Viale Regina Elena 299, 00161 Rome, Italy
Luca Lucentini
Istituto Superiore di Sanità (ISS), Viale Regina Elena 299, 00161 Rome, Italy
Mario Palermo
Regional Health Authority of Sicily, Via Vaccaro 5, 90145 Palermo, Italy
Walter Pollina Addario
Regional Health Authority of Sicily, Via Vaccaro 5, 90145 Palermo, Italy
Giorgio Graziano
Clinical Epidemiology Unit, Regional Reference Laboratory of Western Sicily for the Emergence of COVID-19, University Hospital “P. Giaccone”, Via del Vespro 133, 90127 Palermo, Italy
Palmira Immordino
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Francesco Vitale
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
SARI Collaboration Group
Walter Mazzucco
Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro”, University of Palermo, Via del Vespro 133, 90127 Palermo, Italy
Wastewater-based epidemiology is a well-established tool for detecting and monitoring the spread of enteric pathogens and the use of illegal drugs in communities in real time. Since only a few studies in Italy have investigated the correlation between SARS-CoV-2 in wastewater and the prevalence of COVID-19 cases from clinical testing, we conducted a one-year wastewater surveillance study in Sicily to correlate the load of SARS-CoV-2 RNA in wastewater and the reported cumulative prevalence of COVID-19 in 14 cities from October 2021 to September 2022. Furthermore, we investigated the role of SARS-CoV-2 variants and subvariants in the increase in the number of SARS-CoV-2 infections. Our findings showed a significant correlation between SARS-CoV-2 RNA load in wastewater and the number of active cases reported by syndromic surveillance in the population. Moreover, the correlation between SARS-CoV-2 in wastewater and the active cases remained high when a lag of 7 or 14 days was considered. Finally, we attributed the epidemic waves observed to the rapid emergence of the Omicron variant and the BA.4 and BA.5 subvariants. We confirmed the effectiveness of wastewater monitoring as a powerful epidemiological proxy for viral variant spread and an efficient complementary method for surveillance.
