Journal Article

Effects of Second Dose of SARS-CoV-2 Vaccination on Household Transmission, England

Hall, Jennifer, Andrews, Nick, Dunbar, Kevin, Lopez-Bernal, Jamie, Dabrera, Gavin, Zaidi, Asad, Harris, Ross, Woodhall, Sarah

2023

Overview

A single SARS-CoV-2 vaccine dose reduces onward transmission from case-patients. We assessed the potential effects of receiving 2 doses on household transmission for case-patients in England and their household contacts. We used stratified Cox regression models to calculate hazard ratios (HRs) for contacts becoming secondary case-patients, comparing contacts of 2-dose vaccinated and unvaccinated index case-patients. We controlled for age, sex, and vaccination status of case-patients and contacts, as well as region, household composition, and relative socioeconomic condition based on household location. During the Alpha-dominant period, HRs were 0.19 (0.13-0.28) for contacts of 2-dose BNT162b2-vaccinated case-patients and 0.54 (0.41-0.69) for contacts of 2-dose Ch4dOx1-vaccinated case-patients; during the Delta-dominant period, HRs were higher, 0.74 (0.72-0.76) for BNT162b2 and 1.06 (1.04-1.08) for Ch4dOx1. Reduction of onward transmission was lower for index case-patients who tested positive ≥2 months after the second dose of either vaccine.

• Publisher: U.S. National Center for Infectious Diseases,Centers for Disease Control and Prevention
• Subject: Age / Analysis / BNT162 Vaccine / Control / Coronaviruses / COVID-19 / COVID-19 - epidemiology / COVID-19 - prevention & control / COVID-19 Vaccines / Datasets / Disease transmission / Effects of Second Dose of SARS-CoV-2 Vaccination on Household Transmission, England / England - epidemiology / Health aspects / Households / Humans / Immunization / Infections / Medical research / Medicine, Experimental / respiratory infections / Risk factors / SARS-CoV-2 / Severe acute respiratory syndrome coronavirus 2 / Sociodemographics / Socioeconomics / Statistics / Vaccination / Vaccines / Variables / viruses / zoonoses