Thread by @sailorrooscout

A study out of the University of Illinois shows vaccinated individuals with a “breakthrough” infection are LESS likely to shed infectious virus at a given viral load, shed for a SHORTER period of time compared to unvaccinated individuals, AND report fewer days of symptoms.🧵

To shed light on how vaccine breakthrough infections compared with infections in immunologically naive individuals, researchers examined viral dynamics and infectious virus shedding through daily longitudinal sampling in a small cohort of adults infected with

SARS-CoV-2 at varying stages of vaccination (in this case mRNA & J&J). The durations of both infectious virus shedding and symptoms were significantly reduced in vaccinated individuals compared with unvaccinated individuals. Researchers also observed that breakthrough infections

were associated with strong tissue compartmentalization and were only detectable in saliva in some cases. This data indicates that vaccination shortens the duration of time of high transmission potential AND minimizes symptom duration.

Researchers also found that even with a given viral load value, the probability of viral culture being positive was found to be LOWER in samples from fully vaccinated individuals versus newly vaccinated individuals and unvaccinated individuals, suggesting fully vaccinated-

individuals may be LESS infectious. Altogether, this study provides a set of high resolution data that ratify the role of the current SARS-CoV-2 vaccines not only in reducing severity of the disease, but also the infectiousness of individuals with breakthrough infections.

Also before anyone says “B-but this is Pre-Delta!” Stop. Remember this. These principles would still apply. Differences between unvaccinated individuals and vaccinated individuals are likely to remain the same. The only thing Delta changes is virus circulation due to being a more

transmissible variant. Meaning that exposure risk is higher due to more virus circulating. That’s it. If you need studies regarding Delta, I have those as well (let me know if you do), as they support the same findings in this study.

You can find this study here: medrxiv.org/content/10.110…. If you find you have more time today to read, I also recommend this article. Don’t Worry, Your Immunity is Supposed to Wane: theatlantic.com/science/archiv…