Epidemiology of COVID-19

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Abstract

The review examines and discusses the spread of COVID-19, current sources of the pathogen, mechanisms and ways of transmission of SARS-CoV-2. It is shown that the leading sources of infection in the ongoing COVID-19 pandemic are patients with manifest forms of the disease on the 1st-2nd day of the disease. A week after the appearance of the first symptoms of the disease, the epidemiological significance of patients as sources of infection decreases sharply. And unlike many other respiratory infections, patients with subclinical forms of the disease who remain highly active are less dangerous epidemiologically.

Despite the fact that the causative agents of severe acute respiratory syndrome have penetrated into the human population from small vertebrates, the epidemiological significance of the latter in the ongoing COVID-19 pandemic is negligible. The actual mechanism of transmission of SARS-CoV-2 is aspiration. The other mechanisms of pathogen transmission (fecal-oral, transmissible, contact, vertical), previously discussed as competing with aspiration, have no epidemiological significance. The main transmission path of SARS-CoV-2 is airborne. The contact-household transmission path is much less relevant, and other ways are not proven. Leading in the spread of the virus in the human population is a relatively close (up to 2 meters), long-term, not protected by personal protective equipment, contact of the patient with a healthy one. There is no epidemiological significance of long-distance transmission of the virus.

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About the authors

Murad Z. Shakhmardanov

The Russian National Research Medical University named after N.I. Pirogov

Email: mur2025@rambler.ru
ORCID iD: 0000-0002-3168-2169
SPIN-code: 3312-4052

MD, Dr. Sci. (Med), Professor

Russian Federation, Moscow

Vladimir V. Nikiforov

The Russian National Research Medical University named after N.I. Pirogov

Email: v.v.nikiforov@gmail.com
ORCID iD: 0000-0002-2205-9674
SPIN-code: 9044-5289

MD, Dr. Sci. (Med), Professor

Russian Federation, Moscow

Anna A. Skryabina

The Russian National Research Medical University named after N.I. Pirogov

Email: anna.skryabina.85@mail.ru
ORCID iD: 0000-0002-2098-222X
SPIN-code: 3692-6818
Russian Federation, Moscow

Yuri N. Tomilin

The Russian National Research Medical University named after N.I. Pirogov

Email: papa220471@mail.ru
ORCID iD: 0000-0003-2767-4868
SPIN-code: 8938-2621

MD, Cand. Sci. (Med.)

Russian Federation, Moscow

Aida S. Abusueva

Dagestan State Medical Academy

Email: amur39@mail.ru
ORCID iD: 0000-0002-6999-1696
SPIN-code: 4713-7110

MD, Cand. Sci. (Med.), Associate Professor

Russian Federation, Makhachkala

Svetlana V. Burova

The Russian National Research Medical University named after N.I. Pirogov

Author for correspondence.
Email: svburova@list.ru
ORCID iD: 0000-0001-7664-7685
SPIN-code: 9165-2625

MD, Cand. Sci. (Med.), Associate Professor

Russian Federation, Moscow

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