The outbreak of COVID-19 in the marine barracks shows how the disease spreads

Researchers at Ikarn Medical College and the Naval Medical Research Center on Mount Sinai chose basic marine training because they are mostly closed systems. When new employees arrive, they will stay there for the duration of the training.

This is ideal for studying asymptomatic infections of the coronavirus.

The survey included more than 1,800 Marines from nine different classes. The recruits were quarantined at home for two weeks before arriving at basic training.

This was followed by an additional two weeks of quarantine at the beginning of the basic training. During this time, new employees had to stay in a double room, wear masks, and be physically separated from each other.

Each new employee class was housed in a different building and did not interact. Most of the instruction is given outdoors, and better ventilation reduces the risk of spreading the virus.

Researchers monitored recruits daily for COVID-19 symptoms, including temperature measurements.

They also tested the recruits for virus using the nasal swab PCR test within 2 days of arrival and within 7 and 14 days of arrival.

Within two days of arrival, just under 1% of new employees were SARS-CoV-2 positive. Another 1.9% of new employees were positive on day 7 or 14.

Of the 51 recruits who tested positive on any day, only 5 had symptoms in the week leading up to the test.

New employees who reported symptoms also underwent a PCR test. This test did not detect any positive cases identified by regular nasal swab screening.

Dr. Francesca TrianiThe study, program director of infection prevention and clinical epidemiology at the University of California, San Diego, said it demonstrates the limits of quarantine and measures such as wearing masks and physical distance to control the transmission of coronavirus. It was.

It also shows the limits of using symptoms to identify positive cases.

Tapper and his SFU colleague Dr. Caroline Colleen recently Survey The preprint server medRxiv models how a coronavirus infection occurs in a public school classroom.

They also looked at how strategies such as quarantine, contact tracing, and pooled testing could slow the spread of the virus.

Tupper and Colijn Blog post I will explain the result.

“The results of the new study are consistent with what we found in our study, which means that there is a limit to testing only those who have symptoms,” says Tapper. “Instead, the most effective thing you could do was screen everyone with a coronavirus test.”

Torriani said the test is especially important in group settings where people come into close and frequent contact with others. This begins when they appear.

“If you take people from the outside to a meeting, they can’t be considered negative,” she said. “To protect the population, they need to be tested on arrival before they are released to the environment.”

In this study, new researchers only tested individuals to see how the virus spreads, not as a way to flag people to be quarantined.

However, Torriani said many schools are using tests to identify arriving students who have COVID-19.

“Students are quarantined and tested before they are released into the pod,” she said, but only if the two test results indicate that she is not infected with the virus.

There are few group settings that do not come into contact with the outside world. In other words, there is always a risk of coronavirus invasion.

According to Triani, a truly closed environment can only be found during something like a scientific research mission on a boat. Once on the boat, there is no contact with the outside world until you return to the harbor.

However, most other group settings are only partially closed. At the university, professors and staff travel back and forth between campuses. Even students aren’t on campus all the time.

Therefore, continuous testing is required.

“In a partially closed environment, transmissions can occur due to completely uncontrolled contacts, so we need to continue testing,” Torriani said.

Regular tests can help slow the spread of the coronavirus, but there are other ways that are just as effective.

This includes what Gandhi calls non-pharmaceutical interventions — wearing masks, physical distance, hand hygiene, and good ventilation.

“There are many settings that haven’t been extensively tested, such as hospitals, grocery stores, and critical worker settings,” Gandhi said. “But we rely on non-pharmaceutical interventions and their strict adherence to stay safe. This is actually relatively effective.”

Torriani said multiple layers of protection are needed, including testing, non-pharmaceutical interventions, contact tracing, and quarantine.

This includes smartphone apps that warn people that they may have been exposed to a virus.

“All of this helps,” Torriani said. “By trying to do it collectively as a society, we can go back to work and back to learning.”

“Without them, it would be difficult to do so until the majority of the vaccinated population is available,” Torriani added.