A group of seven Germans aged 25 to 39 have contracted the Omicron variant of the coronavirus in South Africa, although all have already received their booster vaccination. Wolfgang Preiser, a member of the research consortium that discovered the variant, told the Tagespiegel newspaper.

"We are seeing a lot of breakthrough infections right now. What we didn't know is that even the booster vaccination with Biontech/Pfizer doesn't prevent that," Preiser told the Tagespiegel newspaper. These infections are the first reported breakthrough infections with the Omicron variant in people who have already received their booster vaccinations.

"Of course, this should not be misunderstood that vaccination does not help. On the contrary, it just shows that even the best possible vaccination is obviously not enough to prevent infection - which we already suspected," Preiser said.

According to a study Preiser and his colleagues published on the case Thursday, the travel group became infected as early as late November or early December.

All seven had received at least two of their three vaccinations with an mRNA vaccine. Six of them received the Biontech vaccine as their booster, and one received the Moderna vaccine. Six individuals are under 30 years old and one individual is 39 years old.

The individuals received these vaccines in this order:

• Persons 1 through 5: Biontech, Biontech, Biontech.
• Person 6: Biontech, Biontech, Moderna
• Individual 7: Astrazeneca, Biontech, Biontech

Booster vaccinations were administered to subjects between five and ten months after the second vaccinations. The booster vaccinations were at least one month, but no more than two months, the study says. Thus, the affected individuals were among the very early vaccinated in Germany.

None of the seven infected individuals had relevant pre-existing conditions, according to the study, and none had previously tested positive. Four of them were doing medical internships at various local hospitals, and the other three were on vacation. They all tested negative when they arrived in South Africa in the first half of November.

As the seven-day incidence increased significantly in the Western Cape province where they were staying, the seven individuals also developed mild symptoms that began between Nov. 30 and Dec. 2. After testing positive, all individuals went into home quarantine and kept a symptom diary.

During the quarantine, individuals had common Covid 19 symptoms. The most common symptoms were sore throat, fatigue, headache, but dry cough, chest and sinus pressure, rhinitis, and nausea were also reported. One person had night sweats, and another reported a temporary odor and taste disturbances.

The antibody level exhibited by the subjects was at a similar level to four weeks after the second vaccination. In contrast, the viral load of the seven individuals is reported in the study to be higher on average than it was for infections with the original Sars Cov-2 variant from Wuhan, the wild type. However, the study authors note that these are preliminary figures.

However, at 10h7, the omicron variant achieved lower viral loads than the alpha variant in the cases from South Africa four days after symptom onset. According to measurements by the Christian Drostens research group at the Charité, the alpha variant can reach viral loads of 10h8 four days after the onset of symptoms.

None of the seven Germans had to deal with a severe course of the infection. "Of course, you can say now: these are young people anyway. But you can already assume that at least a severe course is prevented," Preiser said. This conclusion is also supported by the first data from a Biontech study, company CEO Ugur Sahin announced on Wednesday.

Breakthroughs show: The adapted vaccine is needed

Biontech and Pfizer had said Wednesday that, according to their laboratory study, a booster vaccination neutralized the Omicron variant, while the variant could breakthrough vaccine protection after only two vaccinations.The third vaccination allowed the antibody level to increase 25-fold compared to two vaccinations. This level provides a high level of protection against infection with all known virus variants, the companies explained.

On the one hand, the booster breakthroughs in South Africa that have now become public are a setback. But they also show what the companies have already announced: that an adapted vaccine is needed. Biontech and Pfizer expect to have that adapted vaccine ready by the end of March.

As Biontech CEO Sahin explained in an interview with Der Spiegel on Thursday, the decision has not yet been finalized on whether an Omicron vaccine will be produced. Sahin affirmed that in his opinion, current vaccines can still protect well against severe disease. Sahin also brought a timely fourth vaccination into play, then with the new vaccine for the variant.Until then, Wolfgang Preiser explained, booster vaccination is the only thing that will help against Omicron. "But you have to be aware that even that doesn't prevent infection 100 percent. In other words, you have to keep taking precautions."

Image by Alexandra Koch