Bar charts showing the distribution of cases with documented and undocumented (including asymptomatic) dates of symptom onset within the population.

<p>(a) gender of cases, (b) age group of cases in years, (c) education level of cases: No schooling (N), Primary school (P), Secondary school (S), (d) occupation of cases: Student (S), Stay at home (H), Factory worker (W), Construction worker (C), Child (Ch), Vendor (V), Farmer (F).