Vaccinated People Aren’t Just Less Likely to Get Covid, But Less Likely to Transmit It Too: New Study

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One of the unanswered questions about the various coronavirus vaccines is whether they can help prevent you from not just getting sick, but also from transmitting the virus to others. A new study conducted in Israel had some very encouraging results on this topic.

The various vaccines currently in use around the world were approved after studies were able to show that they were effective at preventing people from getting severely ill or dying from Covid-19 and — most importantly — safe. But there was insufficient data at the time to be able to conclusively say whether or not the vaccines were able to reduce transmission of the virus, especially considering the concern about asymptomatic carriers still being contagious.

According to an article by The Times of Israel, the country’s largest testing lab, which handles more than 10,000 Covid-19 tests per day, is reporting that their data showed “positive test results of patients age 60 and over had up to 60 percent smaller viral loads on the test swab than the 40-59 age group, starting in mid-January, when most of Israel’s population age 60-plus had already been vaccinated with at least one dose.”

Professor Yaniv Erlich, the head of the lab that worked on the study, told the Times that before Jan. 15, the two age cohorts had “only negligible differences,” and after that date, the viral load began to drop for the 60-plus group.

“We checked the early December and late December [data], but the viral load among 60-plus hadn’t changed,” said Erlich. “And we saw the same when we checked in early January. But suddenly, during the last two weeks in January, which is when many 60-plus Israelis had finished vaccination, viral loads for this age group dropped.”

In other words, if someone who has been vaccinated contracts Covid-19, this data seems to indicate that they will have a lower amount of the virus present in their nose and throat, the main ways that the coronavirus is transmitted to other people.

The study is mostly relevant for the Pfizer-BioNTech vaccine, because that’s the version that most Israelis have received, but last week, the researchers working on the Oxford-AstraZeneca vaccine released a study with some hopeful signs that their vaccine may help reduce transmission as well.