An investigation is underway after eight classmates at an elementary school in the Lower Merion School District, as well as two family members who were fully vaccinated, tested positive for COVID.
A spokesperson for the district said eight students in a second grade class at Penn Valley Elementary School tested positive. The class has been quarantined since April 15 and so far officials have not seen evidence of linked or in-school transmission at Penn Valley beyond that one class, the spokesperson said.
The school district's health services team is consulting with the Montgomery County of Public Health in the investigation.
“Because this was the first time we observed significant linked (in-school) transmission in our District, the LMSD Health Services team this week went beyond contact-tracing in an attempt to further investigate and understand conditions that could be factors in the outbreak,” the spokesperson wrote. “While the District does not have the ability to determine what strain of COVID is involved in these cases, it is able to look at other factors, such as those within the classroom.”
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The district’s Operations Department made a full assessment of the heating, ventilation and cooling system of the impacted room. Their inspection revealed that a manual damper within the ductwork above the ceiling was too far closed, allowing about 30% of the maximum of fresh air it should have allowed into the room.
“The damper can only be seen by physically going into the duct,” the spokesperson wrote. “The automated system that controls the HVAC equipment did not trigger any alerts indicating repairs were needed.”
At this time, the district “cannot say definitively” whether the diminished fresh airflow contributed to the outbreak, the spokesperson said while also noting that “it could be a factor.”
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The spokesperson also said two vaccinated family members of the impacted students tested positive as well, leading them to believe that they could have been infected with a variant strain of COVID-19.
Vaccination is a vital step in fighting COVID-19 infection, the CDC says, and the coronavirus vaccine is 90 percent or more effective at preventing illness.
A small percentage of those vaccinated could contract COVID-19 after vaccination; there is evidence that these breakthrough infections are less serious than in people who aren't vaccinated.
Staff members performed a deep-cleaning inside the classroom and also ran an HVAC system sensor check. They will also conduct assurance tests of air quality at all buildings over the weekend and in the coming weeks.
Students and parents in the Lower Merion School District are urged to report any cases of or exposure to COVID-19 to the LMSD COVID Healthline by calling 610-645-1973 or by emailing email@example.com.