Of note: The online self-checker is created to help people make "decisions about seeking appropriate medical care" and is not to be used as a "diagnosis or treatment of disease or other conditions, including COVID-19", the CDC states on its website.
People who have caught the virus but don't display symptoms such as cough, fever and muscle pain have been reported in several countries as the pathogen has spread to nearly all parts of the world, killing more than 15,000 (at press time) and sickening more than 340,000.
The WHO has said the role of asymptomatic transmissions in the spread of the disease was not clear, but carriers without symptoms were unlikely to be a key factor overall.
These people were quarantined but not counted in official figures: they were 80,000 at the time. It also does not disclose the number of people in this category, raising concerns that its much-publicised drop to zero new cases last week can not be taken at face value.
According to classified Chinese government statistics seen by the South China Morning Post, as many as one third of those who test positive for COVID-19 are "silent carriers".
The asymptomatic cases in Wuhan were found when patients were admitted to hospitals for medical observation after coming into close contact with confirmed infections, working at quarantine venues or at places with elevated risks of exposure, Caixin reported.More news: Allen has new publisher, memoir out Monday
The Chinese government revised its guidelines on the 7th February, to count only those patients with symptoms as confirmed cases.
South China Morning Put up, no less than 43,000 of China's COVID-19 diagnoses weren't incorporated within the nation's legitimate rely of showed instances.
A man wearing protective mask walks next to Notre Dame cathedral, in Paris.
The earlier report by the WHO's global mission to China had estimated that asymptomatic infections accounted for 1 to 3 per cent of cases. In contrast, Hong Kong, which has successfully been able to contain the virus, tests all arrivals.
In another study, scientists in the United States, France, China, and Hong Kong found that the time between cases in a chain of transmission was less than a week.
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"Of course it is hard to say if they may be less infectious if they don't cough".
The study also said cases with only respiratory problems recover faster than those with both.
He added: 'There are many reports of transmission around one to two days before symptom onset'.
A better understanding of asymptomatic cases could lead to adjustments in public health policy, experts said.
Nishiura added: 'The asymptomatic ratio ... could be higher among children than in older adults.
"That would considerably change our scope of the outbreak, and even the optimal interventions can change".More news: United Kingdom bike shops can remain open during COVID-19 lockdown