Fig 1.
Proportion of samples from all sources tested positive for SARS-CoV-2 during Delta and Omicron wave.
Samples were taken during Delta wave, week 1–24 (27 July 2021–7 January 2022) and Omicron wave, week 26–45 (18 January-3 June 2022). Samples were not collected in week 25 (10–16 January 2022).
Fig 2.
Hotspot location based on the period of sample collection.
4a. During Delta wave between 27 July 2021 and 7 January 2022 and during. 4b. During the Omicron wave between 18 January and 3 June 2022. The classification of hotspots was defined based on the percentage of positive cases in each sampling location adjusted to the sampling frequency in each sampling location (compared to the total weeks of sampling in each Delta and Omicron wave).
Table 1.
SARS-CoV-2 positive detected using N and ORF1ab genes in each sample source and its correlation.
Fig 3.
COVID-19 wastewater surveillance N and ORF1ab genes against new confirmed cases after recovery adjustment by week.
Manhole sites collected by grab sampling (3a, 3c, 3e). NST water collected by passive sampling (3b, 3d, 3f). 3a. correlation between N gene and ORF1ab vs new confirmed cases were 0.808 (P<0.001), and 0.785 (P<0.001), without lag time. 3b. correlation between N gene and ORF1ab vs new confirmed cases were 0.763, (P<0.001), and 0.646 (P<0.001), without lag time. 3c correlation between N gene and ORF1ab vs new confirmed cases were 0.776, (P<0.001), and 0.760 (P<0.001), with 1-week lag time. 3d. correlation between N gene and ORF1ab vs new confirmed cases were 0.778, (P<0.001), and 0.658 (P<0.001), with 1-week lag time. 3e correlation between N gene and ORF1ab vs new confirmed cases were 0.754, (P<0.001), and 0.715 (P<0.001), with 2-week lag time. 3f. correlation between N gene and ORF1ab vs new confirmed cases were 0.671, (P<0.001), and 0.558 (P<0.001), with 2-week lag time. Red lines represent new confirmed cases, green lines represent N gene, and blue lines represent ORF1ab gene.