People who have had Covid-19 and who no longer have symptoms may still be positive for the new coronavirus and therefore contagious. For this reason WHO indicates to repeat the test. And if it is not possible, he recommends continuing the isolation for another 14 days.

Much has been said about the contagion and transmission pathways of the new Sars-CoV-2 coronavirus, from the permanence on the surfaces to the possibility that the infection can be contracted by asymptomatic people and much more. But how long is it contagious, even asymptomatic, or after the symptoms of Covid-19 have passed? Even for a long time, days or weeks, as the World Health Organization has just explained and as experts on the front line against Covid-19 testify. This is because even if you no longer have symptoms, you can still be positive for the virus and therefore potentially able to transmit the virus. This is why the WHO, in a dedicated guide, recommends repeating the test to verify negativeization. But, if you can not (or in poor countries where the health system overloaded or without media does not allow) to stay at home anyway, in isolation, for another 14 days after the end of symptoms. This period is a window-period, which serves to protect other people from infection. That’s when you are contagious and how it works in Italy.

When you are healed and when you are no longer contagious

Having no more symptoms does not necessarily mean being cured. Or rather, it indicates that you are ” clinically healed ” according to the definition of the Superior Health Council but you can still have the positive Sars-CoV-2 test. While the real “healed” also have a negative test.

In other words, despite being asymptomatic, the virus can still be present in our body and in that case it can be contagious. For this reason, even if the probability of asymptomatic infection is lower (but it is still present, as shown by various studies) one must be careful.

Regarding the length of the period in which one is still contagious at the end of the symptoms, there is no fixed rule, as Pier Luigi Lopalco, epidemiologist and professor of hygiene at the University of Pisa explains to Wired. “There is great variability” – explained the expert –  “so that patients who no longer have the disease can still be positive for the virus for a few days, as for two weeks” .

What the WHO and other authorities say

For this reason, the WHO recommends that people who are positive for the new coronavirus and with mild symptoms, who are therefore in isolation and treated at home, must carry out the test once they no longer have the symptoms, to verify that it is negative. This is also the case in Italy , where the Ministry of Health indicates to test the patient when the symptoms disappear and in what has always been asymptomatic but positive not earlier than 14 days after the first detection of the virus. The test must be repeated twice consecutively at a distance of 24 hours from each other.

“Until you have the patients confirmation of negativity they can not go out and have to stay still in isolation” – adds Lopalco – ” and even after you tend to recommend yet extend precautionary measures to further confirm the data” .

Without testing, however, stay home for 14 days

But if, for other reasons, it is not possible to repeat the analysis? The World Health Organization recommends that the person remains at home for two more weeks, continuing the period of isolation. “People infected with Covid-19 can still infect other people after they stop feeling sick, “ WHO director-general Tedros Adhanom Ghebreyesus said in one of the latest media briefings, “therefore precautionary measures should be put in place. act for two weeks after the disappearance of symptoms “. And, he adds, visitors are not allowed for 14 days.

Precautionary measures

But what precautionary measures are you referring to? All positive cases, even with mild symptoms, must be isolated by staying in the home (where hospitalization is not necessary) and not going out. And isolation must continue even after the end of clinical manifestations, for at least 14 days. During this period, family members and caregivers must continue to take the same precautions, as explained by the WHO, including wearing a mask for both the positive person and the caregiver.