Fig 1.
Weekly positive samples sequenced by WHO classification label (stacked bars) and the log-transformed number of cases in Wales (gray shaded area).
A total of 251,329 positive samples were sequenced or genotyped over the study period.
Fig 2.
Rolling 7-day average number of samples by sample date and infection type.
Table 1.
Delta and Omicron reinfection counts and percentages by sample origin.
Percentages computed by column.
Table 2.
Delta and Omicron reinfection counts and percentages by first infection variant.
Percentages computed by column.
Fig 3.
Mosaic plot of the number of reinfections by first infection and second infection variant.
The area of each tile is proportional to the corresponding contingency table cell count in Table 1. The vertical height of each tile in the first (second) column reflects the proportion of Delta (Omicron) reinfections that were associated with an initial Wuhan-Hu-1, Alpha, Delta or Omicron infection. The tile shading represents the magnitude and sign of the Pearson residual for the cell of the associated contingency table. Red indicates a cell with fewer cases than expected whereas blue indicates a cell with more cases than expected under the null model.
Fig 4.
First-to-second COVID infection interval by second infection variant.
Stacked and un-stacked histograms (left and right, respectively).
Table 3.
Inter-infection intervals (days) by second infection variant.
Table 4.
Characteristics and exposures of Delta versus Omicron reinfection cases.
Table 5.
Characteristics and exposures of Omicron versus Delta reinfection cases—Odds ratios.