Fig 2. Susceptibility analysis showing forest plot comparing odds ratios (OR) of secondary attack rates among (0–9 years old) child contacts and adults, among (10–19 years old) adolescents and adults, as well as among children and adolescents combined (0-19-year-old) and adults; wild-type, alpha variant, delta variant; ordered by descending OR.

Note: NaN—Not a number, inestimable, mean (0/0).