We know that SARS-CoV-2 was circulating, perhaps widely, in southern California as early as the beginning of February 2020. Many cases, particularly in young people, are mild or even asymptomatic. Health clinics now provide antibody tests, which are tests for whether your immune system has previously been exposed to the SARS-CoV-2 virus and recovered. People who have these antibodies may have immunity to future exposure.

Suppose there are 115,192 confirmed COVID-19 cases in California with a population of 39.5 million people, what is the prevalence?

a.

3 out of every 1000 people

b.

3%

c.

33.333%

d.

3 out of every 100 people