Universal testing may help reduce COVID-19 infection: JHU study

Researchers at the Johns Hopkins University (JHU) have stressed that universal testing may help reduce the spread of SARS-CoV-2 -- the virus that causes COVID-19.

According to estimates in an article published in The New York Times, although only 10 per cent of COVID-19 cases in the US have occurred in long-term care facilities, they are responsible for 42 % of deaths caused by the disease.

However, a team of infectious disease experts at JHU believes the actual number of COVID-19 infections nationally in long-term care facilities may be much higher because healthcare providers are missing asymptomatic cases.

This discrepancy may make it more difficult to reduce or prevent the spread of Covid-19 in the very susceptible population living in these centres, the researchers warned in a study published in the journal JAMA Internal Medicine.

"More testing resources are urgently needed to identify the true burden of COVID-19 in long-term care facilities so that we can be more successful in curbing infection and mortality in one of the disease's major hot spots," said study senior author Morgan Katz from the JHU.

In their study, the researchers performed "universal testing" for SARS-CoV-2 among all 893 men and women at 11 long-term care facilities in Maryland, US.

Previously, only residents who showed symptoms of COVID-19 had been "target tested" by the local health departments.

Among the 893 universally tested, 354 people -- nearly 40% -- were found to be positive for SARS-CoV-2 RNA, compared to 153 (17 %) identified in earlier target testing based on symptoms.

The universal screening, therefore, raised the number of COVID-19 cases among the residents in the state's long-term care facilities from 153 to 507 (57 %), a 231 % increase. Of those who tested positive, the researchers reported that 281 (55 %) were asymptomatic.

"These results underscore the importance of universal testing, as symptom-based approaches may miss a substantial number of cases in long-term care facilities," said study lead author Benjamin Bigelow.

"Unrecognised asymptomatic cases among residents can severely hinder preventive strategies and increase the risk of the virus dangerously spreading," Bigelow added.