Analysis carried out by scientists at the Sichuan University, China, shows that even those who do not develop symptoms of the disease can spread the virus in the environment.
One of the mysteries about Covid-19 that scientists have sought to solve is the extent to which asymptomatic patients – that is, who have no manifestation of the disease – have the ability to spread it. This is what scientists at the Sichuan University, China, investigated in a study published in the open-access journal mSphere last Wednesday (24).
The researchers analyzed samples taken from the environment and air from six intensive care unit (ICU) rooms in which 13 patients with Covid-19 were present, two of whom were asymptomatic. Samples were taken from bedrails, room and toilet door handles, light switches, foot flush buttons, sink rims, sink and toilet bowls and drains, bedside tables, bedsheets, pillows, equipment on the walls, floors, air exhaust outlets and the air itself.
The researchers found that 44 of 112 surface samples (39.3%) tested positive for the new coronavirus; in the case of material collected in the air, all were negative. Among the places with the highest rate of contamination was the room of one of the asymptomatic patients: bedrails, pillow, bedsheet, and air exhaust outlet were seriously contaminated by Sars-CoV-2.
“This highlights that asymptomatic COVID-19 patients can contaminate their surroundings and therefore make persons who have direct contact with them such as their family members and healthcare workers be exposed to SARS-CoV-2,” said study leader Zhiyong Zong in a statement. “The findings also highlight that environmental cleaning should be emphasized.”