Omicron variant present in Zurich since November

Analysis of wastewater shows the Omicron variant has been present in Zurich since mid-November, earlier than previously thought.

Wastewater analysis shows Omicron was prevalent in Switzerland's largest canton of Zurich earlier than previously thought. Image by Michal Jarmoluk from Pixabay
Wastewater analysis shows Omicron was prevalent in Switzerland's largest canton of Zurich earlier than previously thought. Image by Michal Jarmoluk from Pixabay

Experts at the Swiss Federal Institute of Aquatic Science and Technology (EAWAG), part of the Eidgenössische Technische Hochschule (ETH) Zurich, said residues of the Omicron Covid-19 variant were detected in the canton’s wastewater as early as mid-November 2021. 

The researchers made the announcement on January 5th, telling Swiss broadcaster SRF that signs of the variant were detected at the Werdhölzli water supply station in Zurich. 

The variant, which was first detected in South Africa, was first identified in Switzerland in late November in the cantons of Geneva and Basel, but was not detected in Zurich until early November. 

READ MORE: First Omicron cases detected in Switzerland

By December 28th, the variant was dominant in Switzerland. The variant is also dominant in the canton of Zurich, Switzerland’s largest, and has an approximate 60 percent share of new infections. 

The variant is believed to be more infectious and spread much easier than known variants of the virus, although some early suggestions indicate it may lead to more mild courses of Covid disease. 

Wastewater analysis has proven to be a useful tool to determine the prevalence of Covid-19 in particular regions, along with the spread of new variants of the virus. 

READ MORE: Omicron officially dominant in Switzerland

Although the variant is now dominant in Switzerland, having replaced the Delta variant, Swiss authorities have previously come under criticism for failing to undertake sufficient sequencing to determine how widespread new Covid variants really are. 

Omicron spread leads to fear of shutdown 

Omicron-led staff shortages are becoming a major problem in Switzerland. This how Swiss companies plan to operate with diminished workforces.

As the highly contagious Omicron variant continues to spread rapidly through the country, it impacts not only the epidemiological situation, but also the economy.

Absenteeism in essential industries is particularly high and is placing Switzerland’s critical infrastructure at risk. 

As at January 4th, 70,302 infected people are in isolation, and additional 31,281 are in quarantine after a close contact with a contaminated person, according to Federal Office of Public Health.

In total, over 101,500 individuals are currently confined and the number is expected to increase, health officials say.

READ MORE: How Switzerland wants to prevent an Omicron shutdown

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

Though Covid has not been a nationwide problem in Switzerland during recent several months, the virus is circulating again and rates of contamination are expected to soar in the coming weeks.

'Over a million people' in Switzerland could be infected with Covid this summer

While the new wave has not been expected to hit before fall or winter,  Swiss health officials now say 15 percent of Swiss population — more than 1 million people — could catch the virus before then.

This is a large number, considering that a total of 3.7 million people in Switzerland got infected since the beginning of the pandemic on February 24th, 2020.

“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.

At the moment, the Federal Office of Public Health (FOPH) reports 24,704 new cases in the past seven days — double of what it was in April.

“The numbers are expected to continue to rise. Note that most of infected people will not be tested, so the number of confirmed cases will be smaller on paper than in reality”, Stadler added.

Although according to FOPH, nearly all cases in Switzerland (99 percent) are caused by Omicron and its sub-variants, which are 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.

Stadler also noted that Omicron virus can’t be compared with the flu, “because we observe long-term consequences much more often during an infection with Omicron than during the flu. Also, Covid can trigger very large waves, even in summer, while large flu outbreaks are rare at this time of year”.

There is, however, some positive news.

“The most recent data shows that 97 percent of the adult population in Switzerland has antibodies against Covid thanks to vaccinations and previous infections”, Stadler said.

Also, “in the long term, things will stabilise. But in the years to come, there will probably be waves in the summer too”.

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