Household transmission of SARS-CoV-2 (COVID-19) in Lima, Peru.

The study aimed to describe the characteristics of SARS-CoV-2 transmission among members of households with a confirmed primary case of COVID-19 in districts with low burden of cases in Lima, Peru, compared to a district with high burden. This was a retrospective study with a secondary database review. Information was collected from an epidemiological surveillance activity in close contacts (household members) in 52 households in Lima, with a single member with COVID-19. Reevaluation was conducted in 10 households. The study evaluated epidemiological and clinical variables and their association with the result of the rapid serological test (presence of IgG, IgM, or both). Secondary cases were found in 40 households, representing mean identification of 49.9% per household. Secondary attack rate in household members was 53% (125 cases), and symptomatic individuals accounted for 77.6% of cases (symptomatic/asymptomatic ratio: 3.5). Presence of fever and/or chills was found in 40% of persons with positive test results, followed by sore throat with 39.2%. Ageusia and anosmia were present in 22.4% and 20.8% of cases, respectively. When there was a primary case of COVID-19 in the household, the secondary attack rate was 53%; however, in an important proportion of households there were no positive cases other than the primary case. The epidemiological and clinical findings were consistent with reports from other international series.