ISSN: 2639-2038
Authors: Turabian JL*
Background: The presence of asymptomatic secondary cases within the family biases the transmission study, since it is not possible to determine whether these were secondary cases or index cases. Objective: To study the characteristics of the index cases and the contacts in the families that did not have asymptomatic secondary cases. Methodology: An observational and retrospective study of families was conducted from March 15 to December 31, 2020, in which there were at least one primary case or index and one secondary case, and they had no asymptomatic case, in a general medicine office in Toledo (Spain). Results: Eighteen families (50 people) who did not have asymptomatic secondary cases were included, with 18 primary or index cases and 32 cohabitants, of which 26 were secondary cases (with positive PCR) and 6 non-ill (with negative PCR and asymptomatic). The secondary cases only differed statistically significantly from the index cases because they were more frequently female (73% vs. 28%). The healthy cohabitants with respect to the secondary cases in the families were more frequently men (17% vs. 73%), specialized workers (83% vs. 27%), and there was a greater number of people in these families (67% vs. 19% families with => 4 members). None of the characteristics studied in the primary cases was statistically significantly associated with the secondary cases vs. healthy cohabitants. Conclusion: In the context of general medicine in Toledo (Spain), the index cases in families without asymptomatic cases are men who transmit the disease to women, with other men with a higher professional level remaining healthy in the family and living in larger families. With respect to what is known, social factors lose importance in families without asymptomatic cases.
Keywords: COVID-19; SARS-CoV-2; Asymptomatic infections; Epidemiological characteristic; household transmission; Household contact; Second Infection rate; Family Characteristics; Risk Factors
