You have a COVID but are vaccinated. How sick are you?

Unvaccinated pandemics are now threatening vaccinated people, but new evidence shows that these amazing “breakthrough” infections tend to be milder, shorter, and occasionally spread to others. is showing.

Dr. Ralph Gonzalez, Chief Innovation Officer at the University of California, San Francisco, said this trend was combined with a mask-free rally that began after the state reopened on June 15 for a highly contagious delta variant. Driven by the emergence. In the past, vaccinated people were most often protected from previous variants and original strains of the virus.

Approximately 90% of recent 183 COVID-19 infections among staff, researchers, and students at the University of California, San Francisco have been found to have been caused by contact with unvaccinated children, partners, or people in the community. It has been. Medical center. Because people are tested regularly, UCSF detects infections, even if they are asymptomatic.

Scientists are still trying to understand the so-called breakthrough infection, which is defined as a positive test result for vaccinated people.

The problem is not that Delta is dodging the vaccine. Instead, our bodies are a little slower to respond to Delta’s onslaught.

William Hanage, an epidemiologist at Harvard TH Chan School of Public Health, said:

The virus can multiply so quickly that “it can manage to copy itself before the immune system wakes up and stamps,” he said.

These cases remain very rare.New analysis available State-level breakthrough data According to the Kaiser Family Foundation, of the COVID-19 cases in California, 1.4% were vaccinated and 98.6% were unvaccinated.

There are major reasons why vaccinated people are unlikely to be the main cause of a pandemic. In the first place, they are much less likely to get infected.

In some groundbreaking cases, people may carry trace amounts of the virus because the immune system already detects and controls the virus. In other cases, the virus may be abundant enough to be transmitted to others, but it is controlled more quickly than unvaccinated people.

While the Centers for Disease Control and Prevention cites Recent clusters of groundbreaking cases In Provincetown, Massachusetts, there was only one case in UCSF where a vaccinated person infected another person at work with the virus as evidence that the vaccinated person could easily infect the virus. He said.

One of the obvious differences is masking. “Vaccination-to-vaccination transmission is extremely rare,” says Gonzales, especially in an environment where people wear masks, such as UCSF.

And new research Breakthrough case in Singapore It also sheds light on why vaccinated and unvaccinated people do not spread at the same rate. Even if both groups had the same level of virus, vaccinated patients appeared to clear the virus from the body at a faster rate. This probably reduces the risk of infection, as the person will be infected for a shorter period of time.

“Based on our data, vaccination may reduce secondary infections, but this needs to be further studied in larger regional surveillance studies,” said Po Ying Chia of the Singapore National Center for Infectious Diseases. I reported.

For vaccines Remains overwhelmingly strong, Experts say. Vaccines will be slightly less effective during this current surge. Some estimates indicate that delta infection prevention is about 80%, down from 95% of alpha variants. However, they are almost completely effective in fending off serious illnesses, 95%.

According to a report released last week, most of the 10,262 breakthrough infections in the United States reported by the CDC in May were mild. About 27% were asymptomatic, 10% required hospitalization and 2% died.

The symptoms reported by people with breakthrough delta infections differ from those seen during the alpha mutant illness, Gonzales said.

The disease tends to be an upper respiratory tract infection, he said, with symptoms in the head and sinuses. You may experience sore throat, headache, loss of smell and taste. However, they rarely get diseases of the lower respiratory tract, such as fatal lung inflammation. At the University of California, San Francisco, hospitalization was required for only one groundbreaking case and was not given due attention. This person received extra oxygen and was discharged within 3 days.

“People are ill. Some of them have a fever,” Gonzales said. “But they are all getting better.”

“The breakthrough is still sick,” he said. However, when compared to unvaccinated COVID-19, “it doesn’t last that long and isn’t too serious.”

A Singapore study also found that fully vaccinated patients had significantly lower odds for moderate or severe outcomes than unvaccinated patients. This finding supports a British study that found that vaccination remained protective against symptomatological and severe illnesses.

Delta is a formidable enemy, said Dr. Robert Wachter, director of medicine at UCSF. It is much more infectious than the original strain. One person infected with the original strain of the virus infected an average of 2.5 others. In the case of Delta, 5-9 new infections can occur in one case. Delta has a longer duration of infection and appears to have high levels of viral shedding for 18 days instead of 13 days. It seems to cause more serious illness. A recent Scottish study concludes that Delta is twice as likely to be hospitalized as Alpha.

Because this variant is currently the predominant strain of COVID-19 in the United States, it is a breakthrough case to monitor vaccine efficacy and inform discussions about booster immunization. Need better monitoring.