CDC: Teachers drive more infections than students
In 10 cases, pupils were the first documented case only once
ATLANTA – A new study found that teachers may be more important drivers of COVID-19 transmission in schools than students.
The paper released Monday by the U.S. Centers for Disease Control and Prevention studied nine COVID-19 transmission clusters in elementary schools in the Atlanta suburb of Marietta in December and January. That included one cluster where 16 teachers, students and relatives of students at home were infected.
In only one of the nine clusters was a student clearly the first documented case, while a teacher was the first documented case in four clusters. In another four, the first case was unclear. Of the nine clusters, eight involved probable teacher-to-student transmission. Two clusters saw teachers infect each other during in-person meetings or lunches, with a teacher then infecting other students.
“Educators played an important role in the spread,” CDC Director Rochelle Wilensky said. “COVID-19 spread often occurred during in-person meetings or lunches and then subsequently spread to classrooms.
The findings line up with studies from the United Kingdom that found teacher-to-teacher was the most common type of school transmission, and a German study that found in-school transmission rates were three times higher when the first documented case was a teacher. In some American districts, schools have had to go all-virtual
because so many teachers were exposed to the virus.
Other research has suggested that there’s low transmission of viruses in schools and that they should reopen for in-person instruction, a message that President Joe Biden’s administration has been pushing in recent weeks to mixed success.
The 8,700-student Marietta district, like all but a handful in Georgia, has been offering in-person classes since the fall. Superintendent Grant Rivera said more than 90% of elementary students came back in person, making some classrooms relatively crowded.
All the Marietta clusters also involved “less than ideal physical distancing,” with students often less than 3 feet apart, although plastic dividers were placed on desks.
“The two main reasons for the spread
of COVID-19 in these schools were inadequate physical distancing and mask adherence,” Wilensky said.
In seven cases, transmission may have taken place during small-group instruction sessions where teachers were close to students. Although the authors said they observed students wearing masks, interviews found that “inadequate mask use” by students could have contributed to the spread of infection in five clusters.
The CDC again advised that schools need to pursue “multifaceted” strategies to prevent the spread of the virus, including cutting down on teacher-toteacher meetings, making sure masks are worn correctly and increasing physical distancing, especially during mealtimes when people can’t wear masks.
Rivera said the school district reengineered instruction in elementary classrooms, making sure students and teachers spend fewer than 15 minutes at a time huddled in small groups and that children are spaced out when they gather on rugs for reading or other activities.
Rivera said the district had been using Fridays not for class time, but for teacher collaboration. Now, the district is encouraging teachers to stay separate.
“We told teachers that all teacher collaboration should occur virtually,” Rivera said.
He also said chairs had been removed from teacher workrooms, that copy machines have in some cases been moved to other places, and that teachers who plan to eat with a colleague have been told they must eat outdoors.
Student meal times pose the biggest challenge, Rivera said.
“To be honest, I’m really struggling with it,” he said.
Students had been kept in classes to limit movement and in isolated pods, but now classes are being encouraged to eat outdoors, with some especially full classrooms going to larger spaces like cafeterias, gyms or auditoriums.
The Marietta district has also continued extensive virus testing after the study ended, Rivera said.
The study also said that in addition to those strategies, it might be desirable to vaccinate teachers to protect educators, cut down on in-school transmission and keep schools operating in person, although the CDC restated that teacher vaccination is “not a requirement for reopening schools.”
American Federation of Teachers President Randi Weingarten said the study “validates” the CDC’S guidelines.
“School buildings can be safe for teachers and kids, but the layered mitigation and testing and tracing must be implemented to curb the risk of transmission, with vaccine availability as another layer of protection,” the teacher union chief said in a statement.
A popular Facebook and blog post by conservative radio host Buck Sexton claims scientific research indicates life should return to normal now despite the persistence of the COVID-19 pandemic.
“Here’s what the science tells anyone who is being honest about it: open the schools, stop wearing masks outside, and everyone at low risk should start living normal lives. Not next fall, or next year – now,” reads the blog post, posted to Facebook on Feb. 8.
We reviewed the scientific evidence and talked to public health experts about Sexton’s post. Overall, they disagreed, noting the ways in which it runs counter to current public health strategies.
‘Opening the schools’
Throughout the pandemic, researchers have studied whether in-person learning at schools contributes significantly to the spread of COVID. The findings have shown that if K-12 schools adhere to mitigation measures – masking, physical distancing and frequent handwashing – then there is a relatively low risk of transmission.
Only seven COVID cases out of 191 were traced to in-school spread in 17 rural K-12 Wisconsin schools that had high mask-wearing compliance and were monitored over the 2020 fall semester. Mississippi researchers found most COVID cases in children and teenagers were associated with gatherings outside of households and a lack of consistent mask use in schools, but not associated with merely attending school or child care.
Sexton’s assertion that schools can reopen leaves out a key piece of information: that safe reopening is highly dependent upon use of mitigation measures that have been shown to tamp down on virus spread.
‘Stop wearing masks outside’
Because the coronavirus that causes COVID is relatively new, the research on outdoor mask use is limited. But so far science has shown that masks prevent virus transmission.
The CDC study published Feb. 10 reported that a medical procedure mask (commonly known as a surgical mask) blocked 56.1% of simulated cough particles. A cloth mask blocked 51.4% of cough particles. And the effectiveness went up to 85.4% if a cloth mask was worn over a surgical mask.
Another experiment from the study showed that a person in a mask emits fewer aerosol particles that can be passed on to an unmasked person. And if both are masked, then aerosol exposure to both is reduced by more than 95%.
Sexton’s post, however, advised that people should stop wearing masks outside.
Overall, the scientific opinion is that, while it may be OK to go maskless outside if you are physically distant from others, mask-wearing is still recommended if you are around others.
‘Everyone at low risk should start living normal lives’
All the public health experts we consulted agreed this part of the claim is absolutely false. It flies in the face of what scientists recommend should be done to get through the pandemic.
News reports and scientific evidence show that bars, parties and other large gatherings can quickly become spreader events. Moreover, even young people and those without preexisting health conditions have gotten severely ill with COVID or died of it.
Even if a low-risk person doesn’t get severely sick, they could still infect others in higher-risk groups.
Already almost half a million Americans have died of COVID.
The push to “return to normal” is precisely what let the new variants form and multiply.
Ruling
A blog post by conservative talk show host Buck Sexton claims scientific evidence shows that right now we should “open the schools, stop wearing masks outside, and everyone at low risk should start living normal lives.”
Scientific research shows that in order for schools to reopen safely, risk mitigation measures must be put in place, such as requiring masks, rigorous hand-washing and limiting the number of students in classrooms.
The remainder of Sexton’s statement strays further from current science. Science does not support the idea that the time is right for some people to resume life as normal. That would allow the virus to continue to spread and have a large human cost in hospitalizations and deaths, said the experts.
Sexton’s post is inaccurate. We rate it False.