Transmission of SARS-CoV-2 among US Marines after Quarantine: Case Study

The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has so far infected more than 52.7 million people worldwide and more than 1.29 million people. Died. This highly infectious virus spreads rapidly from person to person, and public health measures to prevent the spread of the infection include strict quarantine and quarantine measures. A team of researchers at the Naval Medical Research Center in Silver Spring, USA, analyzed the risk of SARS-CoV-2 infection among Marines. Their study is “SARS-CoV-2 infection between Marines in quarantine, ”Was published in the latest issue New England Journal of Medicine..

Background

Public health measures to prevent the spread of SARS-CoV-2 include rigorous testing, isolation of active cases, and isolation of cases exposed to active cases.Some large censuses tried to see Effectiveness of The effectiveness of these measures has not been clearly studied among young people, but these measures to break the transmission chain.

The US Department of Defense is also implementing such public health interventions. However, military and Marine recruits face some hurdles in adhering to such measures. These include “limited living space, close contact with people during training plans and other activities, shared dining facilities, and a mix of people across the United States.” According to researchers, these are at increased risk of getting an infection.

The US Marine Corps’ public health program for recruits includes a quarantine period at home. It then requires two weeks of closely monitored quarantine on the closed campus. This is done to prevent the spread of the infection among new employees. During this second quarantine, new employees will need to take certain steps, such as:

• Wear a mask (double layer cloth) indoors and outdoors
• At least 6 feet of social distance
• They did not have access to personal electronics or other items to prevent surface infections
• Routine hand washing
• Sleep in a double room
• Room and bathroom cleaning and hygiene
• Teaching and exercises were conducted outdoors
• Implemented a one-way flow to monitor movement and minimize person-to-person contact
• Daily monitoring of temperature and symptoms

In this new study, a continuous real-time quantitative polymerase chain reaction (qPCR) assay between populations was used to examine viral infections among marine personnel.

Study design

In this study, new employees who underwent two weeks of home quarantine and two weeks of supervised quarantine on a closed university campus. I was also asked to quarantine my home just before going to campus.

All recruits enrolled in the study were tested for SARS-CoV-2 via qPCR using a cotton swab from the nasopharynx. Samples were first collected on arrival and then further sampled on campus on days 7 and 14. Those who did not volunteer for the study underwent one qPCR test at the end of the 14th day quarantine period. At the end of the monitored quarantine, they were allowed to enter Parris Island.

further Phylogenetic analysis To assess the characteristics of the infection, we embarked on a viral gene obtained from a volunteer virus sample. Blood samples were collected to check for IgG antibodies to SARSCoV-2.

The SARS-CoV-2 sequence was performed using the Illumina sequence protocol and the ion torrent sequence protocol. SARS-CoV-2 genomes from patients worldwide were taken from the EpiCoV database (79,840 sequences), a global initiative for sharing all influenza data, and phylogenetic analysis of the samples taken here was performed. ..

result

Overall findings:

• The survey included a total of 1,848 new employees
• From the first test (after two weeks of home quarantine) conducted within two days of new hires arriving on campus, 0.9% (16 new hires) were SARS-CoV-2 positive. ..
• Of the 16 people who tested positive, 15 were asymptomatic
• 35 participants (1.9 percent) tested positive on day 7 or 14
• Therefore, a total of 51 recruits were tested positive.
• Five of these 51 (9.8 percent) were symptomatic in the week before the qPCR test was positive
• 1,554 recruits refused to participate in the investigation and underwent mandatory testing at the end of the 14-day monitored quarantine.
• Of these, 26 (1.7 percent) were positive on day 14.
• 36 SARS-CoV-2 genomes were analyzed from 32 participants
• This showed 6 infected clusters among 18 participants
• According to the analysis, there were multiple local transmissions. This included infections between roommates and recruits within the same platoon.

Local infection of SARS-CoV-2 during quarantine. Participants associated with the two largest transmission clusters (clusters 2 and 5) were identified by the sequence and were roommates or members of the same platoon. This shows that double room and shared platoon membership are important contributors to the transmission. Other infected members of these platoons whose samples were not sequenced may have been infected with the same cluster strain. One recruit from each platoon was found to be infected at the beginning of the quarantine, representing a potential source of each cluster strain.

Conclusions and implications

This study showed that the positive rate for SARS-CoV-2 was 2 percent among recruits who were previously negative at the start of monitored quarantine. Less than 2% had not been tested before and tested positive by day 14. Most recruits who tested positive were asymptomatic and most of the infections were seen among recruits in the platoon. This study provides a useful case study in elucidating the infectious dynamics among Marines under monitored home quarantine and assessing the effectiveness of public health measures implemented to prevent such infections. May be useful.