Dr. Robert Redfield, director of the Centers for Disease Control and Prevention in California, USA, said that up to 25% of people with the new Corona virus have no symptoms. "This is important, because you now have individuals who may not have any symptoms that contribute to the transmission of the disease," Redfield said.
Even if people get sick, he added, they may hide the virus for up to 48 hours before they develop symptoms. "This helps explain the speed of this virus throughout the country, because we have vectors without symptoms and we have individuals transmitting the virus 48 hours before symptoms appear," BBC quoted Redfield as saying.
Recent studies from other countries also show that a non-accidental transmission of "Corona" is possible for example. A study published yesterday, in a journal issued by the CDC, found that among more than 150 cases of "corona" not related to travel In Singapore, 6.4% appear to involve asymptomatic transmission. In another study, scientists reviewed data about "corona" in China outside Hubei Province, and found that 12.6% of cases appeared to involve asymptomatic transmission.
In the light of these data on asymptomatic spread, Redfield said, the Centers for Disease Control and Prevention "strongly" reviews its recommendations on the use of face masks and whether people should wear them if they have no symptoms.