You're fucked.
What evidence do we have that covid-19 vaccines prevent transmission?
Most papers to date (notably, many are preprints and have yet to be peer reviewed) indicate vaccines are holding up against admission to hospital and mortality, says Linda Bauld, professor of public health at the University of Edinburgh, “
but not so much against transmission.”
The first weekly covid-19 vaccine surveillance report for 2022
1 from the UK Health Security Agency (UKHSA) was more positive than Bauld’s assessment—
but didn’t say outright that covid-19 vaccines prevent transmission. “Several studies have provided evidence that vaccines are effective at preventing infection,” it states, “Uninfected people cannot transmit; therefore, the vaccines are also effective at preventing transmission.”
A study
2 of covid-19 transmission within English households using data gathered in early 2021 found that even a single dose of a covid-19 vaccine reduced the likelihood of household transmission by 40-50%. This was supported by a study of household transmission among Scottish healthcare workers conducted between December 2020 and March 2021.
3 Both studies analysed the impact of vaccination on transmission of the α variant of SARS-CoV-2, which was dominant at the time.
A subsequent study,
4 conducted later in the course of the pandemic when the delta variant was dominant, showed vaccines had a less pronounced effect on denting onward transmission, but were still effective.
How could vaccines help reduce transmission?
Vaccines aren’t preventing onward transmission by reducing the viral load—or amount of SARS-CoV-2—in your body. “Most studies show if you got an infection after vaccination, compared with someone who got an infection without a vaccine, you were pretty much shedding roughly the same amount of virus,” says Paul Hunter, professor in medicine at the University of East Anglia. One study,
5 sponsored by the US Centers for Disease Control and Prevention (CDC), found “no difference in infectious virus titer between groups” who had been vaccinated and had not.
Instead, it’s the principle that the UKHSA identified above: if you don’t get infected in the first place thanks to a vaccine, you can’t spread it. Once you’re infected, you still can—although what we know about the window when you’re most likely to transmit the virus to others has improved.