The groundbreaking finding comes after doctors took progressive CT scans of lungs over the course of a week-and-a-half.
“If coronavirus should continue to spread and impact the United States or elsewhere more significantly, this study equips radiologists with the knowledge to recognise and more confidently suggest if a patient has COVID-19 or pneumonia due to another cause,” co-author Michael Chung said.
“This is necessary for prompt diagnosis for any individual patient (which will lead to more rapid and effective care), but also for patient isolation to prevent the spreading of the highly contagious disease.”
For many of the patients, it took six to 12 days for lung disease to fully develop.
The study is based on the CT scans of patients in China, where the disease broke out earlier this year.
“They’ll have no symptoms or very mild symptoms.”
The mucus is then analysed at public health laboratories.
Doctors in the US are now testing antiviral drug remdesivir as a treatment for COVID-19.
The drug was developed to handle Ebola virus, and has since been tested on SARS patients.
The Chinese Centre for Disease Control and Prevention estimates that COVID-19 has a fatality rate of two per cent, lower than SARS or MERS, but 20 times higher than influenza.
“How can they expect normal citizens to contribute to eliminating the potential risk of person-to-person spread if hospitals are waiting to charge us $3270 for a simple blood test and a nasal swab?” patient Osmel Azcue told the Miami Herald.