Unvaccinated ‘three times more contagious’ than vaccinated in Switzerland

Switzerland’s Covid task force has released a range of statistical findings about the transmission of the virus, including the fact that those who have not been vaccinated against Covid are three times more likely to infect others.

A vial of Moderna Covid vaccine
New figures show the degree to which unvaccinated people are contagious when compared to the vaccinated. Photo by Ian Hutchinson on Unsplash

Switzerland’s Coronavirus Task Force on Thursday released a range of findings about the transmissibility of Covid-19 ahead of the planned rollout of booster shots across the country. 

The findings showed the degree to which vaccination prevents further transmission. 

Those who have been vaccinated are three times less contagious than those who have not had the jab. 

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The findings dispel one of the more pervasive myths about the virus which has been circulating since the start of the vaccination campaign, i.e. that the vaccinated and the unvaccinated are just as likely to transmit the virus and infect others. 

The false claim has often been used by Covid sceptics as a reason why vaccines are ineffective. 

Based on these findings, the Task Force said at least 10,000 hospitalisations could be avoided across the country were the remaining vaccine holdouts to get the jab. 

The findings also illustrated that booster shots would prevent an additional 10,000 to 20,000 hospitalisations. 

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The study took into account infectiousness of people who are fully vaccinated with the Biontech/Pfizer vaccine. 

While the study looked primarily at how infectious vaccinated people are in comparison to the unvaccinated rather than the reasons, the Task Force said the most likely explanation was that those who have been vaccinated have a lower viral load, or that they are contagious for a shorter period of time. 

Who is Switzerland’s National Covid-19 Science Task Force?

The Swiss National Covid-19 Science Task Force advises public bodies on appropriate courses of action to take during the pandemic, but does not directly make policy decisions. 

The body is made up of 25 scientists in relevant specialised fields who volunteer to be a part of the program. 

One of its main jobs since the start of the pandemic has been to dispel conspiracy theories and fake news about the virus and the government’s response. 

Member comments

  1. In fact most of the infections have the origin in vaccinated people. Apparently, while viral charge is higher in unvaccinated, the behavior of vaccinated tends to be much less cautious.

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Reader question: When will Switzerland authorise second Covid booster shots?

Even as other countries have started to administer fourth doses of a Covid-19 vaccine and the infections are on the rise again, Swiss health authorities still haven’t rolled out second boosters. This is why, and what lies ahead.

Reader question: When will Switzerland authorise second Covid booster shots?

As The Local reported on Tuesday, coronavirus is circulating again in Switzerland and rates of contamination are expected to soar in the coming weeks.

In fact, over a million people in Switzerland could catch the virus this summer.

 “More than 80,000 new contaminations per week” are expected in the next two months, according to Tanja Stadler, the former head of the Covid-19 Task Force — much more than during the past two summers, when the rate of infections slowed down.

READ MORE: ‘Over a million people’ in Switzerland could be infected with Covid this summer

Data from the Federal Office of Public Health (FOPH) indicates that the upward trend is already underway. The number of new reported cases has been soaring in the past few weeks — from below 10,000 a week in mid-April and beginning of May, to 24,704 new cases in the past seven days.

These are officially registered contaminations, but as “most of infected people will not be tested, the number of confirmed cases will be smaller on paper than in reality”, Stadler pointed out.

Although nearly all cases in Switzerland (99 percent) are caused by Omicron and its sub-variants, which are more contagious but less severe that the original Covid viruses, “more vulnerable people are likely to end up in hospital, and long Covid cases are also likely to rise”, she said.

What is FOPH’s official stance on second boosters?

Health authorities are currently recommending them only for people in high-risk categories — that is, those with a very weak immune system.

“There is no need for the general public to receive an additional booster vaccination in the current situation. According to available data, people who are fully vaccinated or vaccinated and cured are still well protected against severe forms of COVID-19”, FOPH said on May 23rd.

There has been no change in strategy since then, despite the increasing infection rates.

However, authorities relented on one point: they now allow fourth doses to be administered to people whose Covid certificates have expired but who plan to travel to countries where up-to-date immunisations are required.

FOPH said these travellers can get “off-label” shots — meaning being vaccinated before the official authorisation to do so is issued — but these doses will not be free of charge.

“The price will be set by the cantons and the vaccination centres”, FOPH said, adding, however, that “second boosters for people with weakened immune systems will remain free”.

Why are Swiss health authorities dragging their feet in authorising second boosters?

As with the original vaccine rollout at the beginning of 2021, which took longer here than elsewhere, Swiss slowness may be due to the abundance of caution. For instance, drugs regulator Swissmedic “took longer than many countries to approve new vaccines”.

This time around, FOPH is taking its time to examine benefits of second boosters for general population (as opposed to at-risk groups).

Part of it may be the uncertainty prevailing over the efficacy of vaccines, which were conceived to combat the original early strains like Delta, not the variants, and sub-variants, that emerged later.

“The current vaccine does not provide clear protection against the Omicron”, according to Giuseppe Pantaleo, head of the immunology unit at Vaud university hospital (CHUV).

So when will Switzerland authorise second boosters?

Health officials said they will issue official recommendations “before the summer holidays”, which means shortly.

Two scenarios are currently  foreseen by FOPH: “It may be that an additional booster vaccination is recommended only for people over 65 and those suffering from certain chronic diseases, but it is also possible that it will be intended for the entire population”.

READ MORE: UPDATE: When will Switzerland roll out second Covid boosters?