By now almost everyone of us knows someone who has contracted the coronavirus or has had the infection himself. But once you have tested positive for the swab, how long is it okay not to meet family and friends? An article on the New England Journal of Medicine (Nejm) tackles this issue by proposing a “clinical vignette”, that is the brief description of a clinical case with a discussion by the experts on how to act. The case in question is that of a 24-year-old patient, hospitalized for Covid-19 with cough and breathing difficulties, but without fever and not intubated, who is discharged from the hospital after 14 days. Her parents are waiting for her at home, and her father is on immunosuppressive therapy after a kidney transplant. Can he return safely to them without risking infecting his parents or is it better that he remains in isolation? And officially, in Italy, what do our rules provide?
Longform
Covid: when to go to the hospital
by Tiziana Moriconi
Before answering, it is good to provide some more details on the clinical case. The girl, without particular previous pathologies, arrived at the hospital with cough and shortness of breath for 1 week. The symptoms present at the time of admission are noise on auscultation and oxygen deficiency with saturation at 88% – the alert threshold at which to evaluate whether to go to hospital is 92%, as indicated by the Ministry of Health in a circular. The patient was given oxygen and her condition then required hospitalization in intensive care for a few days, even though she was never intubated. After a week of hospitalization, the symptoms regressed and the health workers proceeded to discharge her. The question is: 2 weeks after the onset of symptoms, can you go home safely? The answer is not so obvious and univocal and there are two different interpretations.
Covid: how to cure it in the first week
by Viola Rita
Answer 1: better not
The answer of Valeria Fabre, Professor of Medicine at Johns Hopkins University School of Medicine, in summary it is “better not”. The expert indicates, also in line with the recommendations in our country, that it is better for the patient to remain in isolation for at least 20 days from the onset of symptoms. The expert explains that some studies (still limited) have indicated that after 10 from the onset of symptoms the Sars-Cov-2 virus detected by PCR tests does not grow in laboratory cultures and therefore would not be transmissible. And a large survey carried out in South Korea sets the threshold at one week. However, adds Fabre, some other research – little for now – would indicate that in a small percentage of patients with a positive Sars-Cov-2 swab for an extended time the virus continues to grow in vitro and therefore could still be active even after more than 1 week. The US Cdc centers – the patient lives in the US – provide for 10 days isolation for patients with mild or moderate symptoms and 20 days for immunosuppressed patients, who may be contagious for longer, or with severe Covid-19. In this case, explains Fabre, the patient falls into the second scenario, given that she had severe symptoms, and it is reasonable to hypothesize an isolation of 20 days, even considering that the girl’s father is a subject at greater risk of severe Covid-19.
Answer 2: yes, without any risk
He is of a different opinion Richard Wenzel, professor emeritus at Virginia Commonwealth University, who explains that the patient is in fact not included in cases requiring prolonged isolation. The young woman, in fact, has no previous pathologies or a particular clinical history, is not immunosuppressed and, even if hospitalized in intensive care for a few days, has not been intubated, has never had a fever and the clinical course is to be considered significant. moderate. The expert explains that no study so far has detected the presence of live virus after 9 days of illness and that even in patients with severe and intubated Covid-19 the probability of isolating the virus 15 days after the onset of symptoms is 5%. . And he concludes by saying that the probability of transmitting the infection to an immunosuppressed family member is low.
The rules in Italy
But what are the rules in Italy? While in the first phase it was in fact necessary to remain in isolation until the swab remained positive – which meant for a long time, in rare cases up to 90 days – the rules have changed a bit starting from October 2020. In particular positive but asymptomatic people can resume normal life after 10 days of isolation and a negative molecular buffer or 14 days (even without buffer). For the symptomatic we speak of 10 days of isolation, of which the last 3 (at least) without symptoms and then a negative molecular buffer or, if the buffer remains positive, an isolation of 21 days, of which the last 7 without symptoms and without repeat the swab – a situation similar to that of the case described in the Nejm and answer 1. “In general,” he comments Massimo Andreoni, Director of the Infectious Diseases Unit of the Tor Vergata Polyclinic, “in patients not immunosuppressed and not with severe Covid-19 the probability of transmitting the infection after the 9th day from the onset of symptoms is considered very low. However, for the maximum precaution and protection of all it is good and important to follow the current regulations, which indicate a 21-day isolation. This criterion can be modulated in immunosuppressed patients, so the situation is assessed on a case-by-case basis “.
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