- The CDC is redefining coronavirus close contacts, which is a major change to its COVID-19 safety guidelines.
- The organization now says the 15-minute span it previously outlined does not have to be continuous, as repeated contact within six feet is still extremely risky.
- The new findings might help public health officials improve health measures meant to reduce the spread of the potentially deadly disease.
The novel coronavirus pandemic is the worst pandemic that the world has had to face in 100 years. And the worst is yet to come, according to health experts. The virus is surging in the northern hemisphere, and the number of cases is increasing significantly from day to day in several countries. The colder weather helps the pathogen, and officials worry about a potential coronavirus-flu convergence. On top of that, a vaccine won’t be available in sufficient quantities anytime soon to provide protection.
More than 41.62 million people have been infected so far, and more than 1.14 million died. But there is a silver lining in all of this. Research has progressed at tremendous speed, allowing healthcare workers to adapt treatment protocols and save more lives. Scientists have been able to study various aspects of COVID-19 and understand the novel coronavirus more quickly than other pathogens in the past. This made it possible for public health authorities to adapt their guidelines accordingly in an effort to keep people safe. Now, the latest change comes from the CDC, which made a scary revelation about how the virus spreads. But even so, the discovery could lead to improved health measures and protocols to keep people safer than before.
The CDC published a new study that redefines “close contact” between COVID-19-positive people and healthy individuals.
Previous CDC guidelines said that a person is considered a close contact if they spent 15 minutes or more within six feet of someone infectious. This new study made the CDC change its stance on the matter, Stat explains. The CDC now says that a person who spent a cumulative period of at least 15 minutes over 24 hours within six of someone infectious is now considered a close contact. Those 15+ minutes do not have to be continuous, which is the scary change in CDC’s recommendations.
This rule seems arbitrary, and Stat notes that experts have long warned that one would not have to hit the threshold of 15 minutes for an infection to occur. Too many factors can impact transmission, including the infectiousness of a person, the room’s ventilation, and how the virus travels in the air. Also, researchers are yet to define the minimum viral load that would lead to infection.
A 15-minute window was used as a benchmark to prioritize contact tracing and quarantine guidelines, per Stat.
The new CDC definition for close contact is based on a study involving incarcerated individuals who infected a guard in Vermont at a time when the region had very low community transmission. The correctional officer had no known contact with anyone else, and he always wore a microfiber cloth mask, gown, and eye protection during his interaction with the detained persons. The incarcerated people were wearing masks most of the time, but not all the time:
The correctional officer reported no other known close contact exposures to persons with COVID-19 outside work and no travel outside Vermont during the 14 days preceding illness onset. COVID-19 cumulative incidence in his county of residence and where the correctional facility is located was relatively low at the time of the investigation (20 cases per 100,000 persons), suggesting that his most likely exposures occurred in the correctional facility through multiple brief encounters (not initially considered to meet [Vermont Department of Health’] definition of close contact exposure) with [incarcerated or detained persons] who later received a positive SARS-CoV-2 test result.
The scientists analyzed video footage and found that the staff member was within six feet of them at least 22 times during an eight-hour shift, totaling at least 17 minutes of exposure. The research proves that the longer a person spends near infected individuals, the higher the chances of infection. On top of that, the new findings seem to indicate that even sporadic contact with coronavirus-positive people can lead to infection.
Low-quality face masks can reduce the risk of COVID-19 transmission, but they don’t eliminate it. Only higher-quality face masks like N95 and KN95 masks offer real protection to the wearer. But face coverings have to be used in connection with all the other safety measures, including social distancing and proper hand hygiene. Ventilation might also play a role in transmission, and a different study seems to prove it. Scientists looked at the spread of COVID-19 in airplanes and found that strict face mask use combined with the cabin’s unique ventilation system can stop transmission even if many infected people are on board.
The new CDC study is available at this link.