Comparative Characteristics of a Subsequent Morbidity Wave COVID-19 in Various Regions of the World
Authors: Bavrina A. P. , Saperkin N. V. , Drugova O. V. , Karjakin N. N. , Kovalishena O. V. 
Published: September 2021

Relevance. The COVID-19 pandemic is characterized by a long undulating course. One of the directions of the dynamic assessment of the incidence of this infection is, as is known, the characterization of the determinants of the epidemic process and the study of the actual effectiveness of various measures.

Aims. Were to study the features of the COVID-19 morbidity in the European, American and Asian regions of the world on the example of individual countries with an assessment of the possible impact of regime-restrictive measures on the daily increase in cases.

Materials & methods. A descriptive epidemiological study involved the use of the following data on COVID-19: daily increase in new infections in absolute numbers and relative indicators during 1 June 2020 till 30 November 2020 in five countries (France, Italy, USA, Brazil, India) , description and timing of various restrictive measures. Information obtained from open sources (situation reports from WHO, CDC, ECDC, national ministries of health, etc.). Time series characterized, defining sharply differing values, timing and duration of ups and downs, the rate of average daily growth (decline). Statistical analysis was carried out using the IBM SPSS Statistics 26.

Results. On average, for the analyzed period of time, 1303 were registered in Italy, 4897, France – 52799, Brazil – 31853, India –50507new cases. The average incidence rate in the compared countries ranged from 500.98 ± 417.06 per 100,000 in India to 4399.43 ± 2390.77 per 100,000 in the US. After the passage of the «first wave» of the incidence of COVID-19, regardless of the region of the world, there was an increase in the daily increase in new cases of SARS-CoV-2 in the summer-autumn period of 2020. Furthermore, with the differences in the morbidity rates in the different countries, there were also characteristics the formation of similar to the region. For the European region (Italy, France), there was a simultaneous beginning of an increase in the incidence in August-September 2020, a similar trend towards exponential growth and synchronous fluctuations in the daily increase in absolute cases of diseases. For the countries of the American region (USA and Brazil), a similar sinusoidal nature of the dynamics of the average daily increase in infection cases and its synchronicity until October 2020 was revealed. The Asian region, on the example of India, had significant differences in the dynamics of the analyzed indicators in comparison with the countries of the European and American regions. Differences in the formation of morbidity in the summerautumn period were more pronounced between the regions and related to the level of average daily growth, the incidence rate, the month of the maximum rise in the incidence in this period, and trend differences. Comparison of the ongoing isolation measures with the daily increase in cases revealed their discrepancy. This could create the preconditions for the activation of the epidemic process of infection and the ineffectiveness of measures.

Conclusions. We found that in the five countries examined, the situation developed according to a similar scenario. Nevertheless, in different regions of the world there was a specificity in the involvement of the territory in the epidemic process. A more in-depth study of the timeliness and completeness of regime-restrictive measures against SOCID-19 should include a comparison with the patterns of formation and manifestations of the epidemic process. In turn, this is important for scientifically based implementation and increasing their effectiveness.