Published in


Higher viral load of SARS-CoV-2 found in pre-symptomatic patients

News | Jazryl Galarosa

Pre-symptomatic patients were found to have a higher viral load (VL) of 2019 novel coronavirus (SARS-CoV-2) and are at risk of actively shedding the virus more than patients with severe symptoms, a study in the American Journal of Pathology showed.

Pathologists from New York University Langone Health observed 205 patients with SARS-CoV-2 in a tertiary care center in New York and found that the amount of SARS-CoV-2 viral load is significantly lower in patients with severe symptoms. The study utilized quantitative polymerase chain reaction, a method which amplifies a DNA strand to rapidly create copies of a DNA sample, to determine viral load.

“Our findings suggest a higher shedding risk in less symptomatic patients; an important consideration for containment strategies in SARS-CoV-2,” pathologists from New York University Langone Health reported in their study.

They also found out through regression models that VL after diagnosis is “significantly lower” in patients who were hospitalized than patients who were not hospitalized. While they found an association between VL and history of cancer, they did not note a correlation between VL, admission to intensive care units, length of oxygen support, and overall survival.

“Our study should increase awareness and should prompt the adherence to strict recommendation of social distancing and mask usage to avoid transmission,” the pathologists concluded as their results support the notion that less symptomatic patients can be a source of the virus.

Dr. Alexander Young, UP’s first professorial fellow originally trained in biomedical sciences, in his talk “Demystifying COVID-19: Pathophysiology, Mechanisms of Transmission, and Environmental Origins of the SARS-CoV-2 Virus” agrees that the viral load peaks during the early stages of the infection.

“What seems to be happening is that these pre-symptomatic patients are actually shedding virus before they know that they have the virus,” Young said, citing another study on young to middle-aged people with mild symptoms which showed similar results.

He added that such estimations of the percentage of infectious asymptomatic individuals worldwide vary widely since data are incomplete without mass testing. Further studies must be done since “the information will still evolve.”

“It’s just too soon to tell since it is the first time that we had a virus like this,” Young stated.

In controlling the spread of COVID-19 in the Philippines, Young suggested that the country must practice mass testing, education on the coronavirus, and aggressive quarantine, adding that the spread of the virus in the Philippines is still controllable.

Citing Taiwan and South Korea as the countries who successfully flattened the curve of the pandemic, he said, “They learned from the SARS outbreak 20 years ago. They knew exactly how to act aggressively.”

Department of Health secretary Francisco Duque III said that the Philippines has “bent the curve in April after the March ECQ (enhanced community quarantine),” citing the case doubling time and longer mortality doubling time of the virus despite rising cases for COVID-19 and lack of mass testing.

As of July 17, the Philippines recorded 1,841 new cases for a total of 63,001 cases nationwide. Out of the reported cases, there are 39,593 active cases, 21,748 recoveries, and 1,660 deaths.




Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store

The official student publication of the College of Science, UP Diliman.