New research indicates asymptomatic or pre-symptomatic COVID-19 cases are a primary driver behind the virus spreading to others.
Using existing research, the study published in the Proceedings of the National Academy of Sciences found that silent transmission could be responsible for half of COVID-19 cases.
Researchers also found that more than one third of these infections would need to be identified and isolated in order to suppress a future outbreak -- though even immediate isolation of all symptomatic cases would not be enough to get the spread under control.
The model assumed that COVID-19 may be the most contagious during the pre-symptomatic state, which is uncommon for a respiratory infection.
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