The mutated virus is more infectious and causes more severe disease.
After some lull on the coronavirus front, incidence rates have risen alarmingly again. The number of patients exceeded 13 thousand and exceeded the indicators of last summer. In Moscow and St. Petersburg, new restrictions are introduced, weekends are extended. What is the reason for the new round of the pandemic? We asked about this Ivan Konovalov, infectious disease doctor, candidate of medical sciences, associate professor of Pirogov Russian National Research Medical University .
Why are the new variants of Sars-CoV-2 dangerous?
- Ivan Vyacheslavovich, at the very least, but part of the people were vaccinated, and in a year and a half of the pandemic, many were ill and received immunity. School – one of the main breeding grounds – went on vacation. And yet, new growth. Is this the seasonal nature of the coronavirus? Does the warm season create good conditions for propagation?
- Today we can definitely state that there are several reasons that ensure the circulation of the virus in the population. Unfortunately, it is not yet necessary to talk about the formation of the immune layer – vaccination coverage is too small in key groups and among certain specialties (these are older people with chronic diseases, as well as professional groups in contact with a large number of people: teachers, students, doctors , social workers, police officers, etc.).
In addition, the emergence of a new “Indian” strain – delta coronavirus, is accompanied by greater virulence (the ability to infect), the ability to infect faster and cause more severe forms. The Indian strain is also resistant to treatment plans, including in younger people. Note that the percentage of asymptomatic individuals dropped significantly compared to last year’s outbreak, when it was mainly the modified “Wuhan” and then the “British” strain circulating. Therefore, the avalanche-like increase in the number of confirmed cases of infection is also accompanied by a statistically significant aggravation of the clinical picture, since a person without symptoms could much more easily leave the examination and, accordingly, from detection, which is reflected in the statistics.
To date, the overwhelming number of registered cases of infection in persons with clinical symptoms: these are people who, even at a young age, can tolerate COVID-19 in a moderate to severe and even severe form of the course, including those without underlying chronic pathology.
If we talk about the socially significant causes of the epidemic rise, then this, of course, is the non-compliance by people with measures of both specific protection – vaccine prophylaxis – and neglect of personal protection measures, distance, isolation in the presence of minimal symptoms. People are just tired. And the infection, in turn, does not reduce activity, today’s figures for the incidence and workload of hospitals, including in Moscow, clearly demonstrate this.