Seroprevalence of COVID-19 Among Sanitation and Janitorial Workers During the Early Pandemic Phase in Saudi Arabia.

During the early phase of the COVID-19 pandemic in Saudi Arabia, sero-epidemiological studies focused primarily on healthcare workers and blood donors, leaving significant gaps in understanding risk factors for other vulnerable groups. This study aimed to assess the seroprevalence of COVID-19 among sanitation and janitorial workers. A total of 2,597 serum samples were analyzed, including 1,279 from sanitation and janitorial workers, collected from 1 April to 30 June 2020, and 1,318 samples collected from healthy blood donors from 1 April to 5 August 2020 as a control group. The seroprevalence of COVID-19 antibodies was higher among sanitation and janitorial workers: 32.21% (412/1,279) compared to 4.78% (63/1,318) in the blood donor control group. Sanitation and janitorial workers had a markedly higher likelihood of contracting COVID-19 (odds ratio = 0.11, 95% CI=0.08011-0.1397, p<0.0001). A minor but statistically significant effect of gender was observed, with males showing higher susceptibility (odds ratio = 1.74, 95% CI = 1.162-2.660, p = 0.01), while nationality had no significant impact on seroprevalence rates (odds ratio = 0.94, 95% CI = 0.6705-1.323, p=0.8). This study highlights sanitation and janitorial workers as a high-risk group for COVID-19, reporting the highest seroprevalence rate locally during the early pandemic phase.