Rachel

people with coronavirus, but no symptoms, infection of others is "very rare", a world health organization has said scientists.

Although the proportion of persons with a positive test result with no symptoms, it is believed that these infections are usually not passed on.

But the people the disease before the first symptoms occur can give.

The Evidence comes from countries, said implementation of the "detailed contact tracing," Dr. Maria Van Kerkhove,.

Dr. Van Kerkhove, of the head of the emerging diseases that do not differ from the distinction between three categories:

Some of the reports between these categories, while others do, and they said this, together with the relatively small groups of people, which can make it difficult to clear conclusions.

But Dr. Van Kerkhove, said The Weight of The Evidence , it is not suggested to people who never develop symptoms play a significant role in the transmission of The Virus , the Who Said .

And released at the weekend says. "The available data from the determination of contact persons reported by the member States shows that asymptomatic infected persons are much less likely to transmit The Virus than those who develop symptoms,"

In England, The Office for National Statistics (ONS) has been regularly testing a sample of the population.

It has found that those who have So Far been positive Covid-19 tested, only 29% had "no evidence of the symptoms" at The Time they were tested, or on the preceding or following visits.

has An important question of whether asymptomatic persons whose infections can be transferred to others.

contact-tracing studies from A Number of countries suggest that, while "true" asymptomatic cases "rarely" to transfer, transmission of infection can occur before or on The Day of the appearance of the first symptoms, if they are very mild, according to Prof Babak Javid, an infectious diseases consultant at the University of Cambridge.

people can have detectable levels of The Virus in your system for about Three Days before symptoms develop and appear to be able to start it more during this time, especially on The Day before or The Day of the symptoms.

And there are people who have not yet developed, symptoms are unlikely to know that they are infectious, pre-symptomatic transmission has said "significant impact" for the track, trace and insulation measures, Prof Javid.

This underlines the importance of the lockdown measures, "solid reduction[ing] the number of people who are infected," said Prof Liam Smeeth, an epidemiologist at the London School of Hygiene and Tropical Medicine.

While the people seem to be without symptoms to infect in the situation, others, current evidence suggests people with symptoms are at the highest risk.

A positive result alone, you don't say how much of The Virus has someone in your system.

And what is known as the Viral Load , whether an infected person sneezing and coughing, and what kind of contact to affect you with Other People , how likely you are to pass the disease.

Dr. Van Kerkhove noted, since coronavirus "through infectious droplets", it is when people cough or sneeze, you are most able, the disease is transmitted.

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Source of news: bbc.com