Men are the main COVID-19 transmitters: behavior or biology?

Author(s)

Silva, Monize V. R. ; de Castro, Mateus V. ; Passos-Bueno, Maria Rita ; Otto, Paulo A. ; Naslavsky, Michel S. ; Zatz, Mayana

• Document type: Journal article
• Source: DISCOVER MENTAL HEALTH; v. 2, n. 1, p. 7-pg., 2022-01-24.

Abstract

BackgroundCOVID-19 has affected millions of people worldwide. Clinical manifestations range from severe cases with lethal outcome to mild or asymptomatic cases. Although the proportion of infected individuals does not differ between sexes, men are more susceptible to severe COVID-19, with a higher risk of death than women. Also, men are pointed out as more lax regarding protective measures, mask wearing and vaccination. Thus, we questioned whether sex-bias may be explained by biological pathways and/or behavioral aspects or both.MethodsBetween July 2020 and July 2021, we performed an epidemiological survey including 1744 unvaccinated adult Brazilian couples, with there was at least one infected symptomatic member, who were living together during the COVID-19 infection without protective measures. Presence or absence of infection was confirmed by RT-PCR and/or serology results. Couples were divided into two groups: (1) both partners were infected (concordant couples) and (2) one partner was infected and the spouse remained asymptomatic despite the close contact with the COVID-19 symptomatic partner (discordant couples). Statistical analysis of the collected data was performed aiming to verify a differential transmission potential between genders in couples keeping contact without protective measures.ResultsThe combination of our collected data showed that the man is the first (or the only) affected member in most cases when compared to women and that this difference may be explained by biological and behavioral factors.ConclusionsThe present study confirmed the existence of gender differences not only for susceptibility to infection and resistance to COVID-19 but also in its transmission rate. There are sex differences in COVID-19 susceptibility and transmission between couples highly exposed to SARS-Cov-2 without protective measures;Men are more efficient virus transmitters than women;Sex-bias in COVID-19 transmission can be explained by differences in viral load in saliva, immune response and also behavioral protective differences between genders. (AU)

• FAPESP's process: 20/09702-1 - Study of protective genetic variants in resilient nonagenarians and centenarians
• Grantee: Mateus Vidigal de Castro
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/50931-3 - Aging and genetic disorders: genomics and metagenomics
• Grantee: Mayana Zatz
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/08028-1 - CEGH-CEL - Human Genome and Stem Cell Research Center
• Grantee: Mayana Zatz
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC