how has the virus changed? Questions and answers

That the virus now in circulation is highly transmissible is evident from the continuous increase in infections. On the other hand, the pathogenicity, that is the ability of the omicron 4 and 5 variants to cause more or less serious disease, is what is being discussed. While it is true that most of the people who become infected manage to manage the symptoms at home, the occupancy rate of intensive care is concerned, which according to data from the Ministry of Health has now risen to 2.6 per cent; demonstrating that omicron 4 and 5 variants can also be dangerous. What makes the difference now is the reaction of the individual who becomes infected, and therefore the ability to defend themselves thanks to the protection of the vaccine.

WHAT ARE THE SYMPTOMS OF OMICRON?

“In subjects who do not have previous diseases – specifies Claudio Mastroianni, director of infectious diseases of the Policlinico Umberto I in Rome and president of the Italian Society of Infectious and Tropical Diseases – the virus mostly affects the upper respiratory tract, manifests itself with high fever , sore throat, diarrhea and a marked sense of exhaustion. In immunocompromised patients, on the other hand, we still observe pneumonia ». Loss of taste and smell and involvement of the lower respiratory tract are less frequent. But the symptomatology depends, as always, on the individual subjects. “The most substantial difference – specifies Mauro Pistello, professor of Microbiology and Clinical Microbiology at the University of Pisa and vice president of the Italian Society of Microbiology – is observed above all in the incubation period that elapses between contagion and onset of symptoms. While before it was about two weeks, and sometimes even more, now it reaches a maximum of two or three days ». Omicron, in fact, being very transmissible, replicates more rapidly in the upper respiratory tract.

DO THE INHABITED HAVE DIFFERENT CHARACTERISTICS THAN BEFORE?

“In addition to unvaccinated, and around in Italy there are still 7 million – recalls Mastroianni – mainly frail people are hospitalized, therefore the elderly who have various comorbidities, chronic bronchitis, diabetics, people with disabilities. This infection, which manifests itself with fever and exhaustion, can in fact cause decompensation and aggravation of previous diseases ». The concern, for those in the ward, is that the situation could degenerate. “Slowly hospitalizations are increasing, and among these there is also an increase of patients in intensive care. And by increasing the number of infected people – warns Mastroianni – the number of hospitalized will inevitably grow, even if perhaps not dramatically as in the first and second wave. If today we are about 80-90 thousand cases a day and the number of deaths is much lower than in previous years, it means that the immunity of the vaccine and that induced by natural infection have somehow managed to counteract the ‘serious evolution’.

IS POSSIBLE THAT POSITIVITY IS DELAYED WITH RESPECT TO THE SYMPTOMS?

If the swab is negative, despite the symptoms already appearing, it mostly depends on the type of anticovid examination. “The results are linked to the sensitivity of the tests and how often they are carried out – specifies Pistello – But that in some subjects the symptoms appear first and then the virus becomes evident is not an unusual fact: many of the symptoms we experience are in fact due to to the host’s reaction to the infection. Obviously, the vaccinated infected individual is much more ready to react. In unvaccinated subjects, on the other hand, the virus finds a free field, after which the immune system goes into action, setting in motion some mechanisms; therefore only in this moment do the symptoms appear ».

ALSO CHANGES THE LONG COVID?

The data available so far are not sufficient to state this. “This virus still causes a systemic disease, there is a fairly important inflammatory picture – clarifies Mastroianni – There are no such differences that allow us to argue that the long covid is different from that of a year ago”.