New COVID-19 Pandemic Waves Caused by Omicron and Efficiency of Vaccinations

The sharp increase in the number of new COVID-19 cases in late 2021 and early 2022, which is associated with the spread of a new strain of coronavirus - omicron - is of great concern and makes it necessary to make at least approximate forecasts for the pandemic dynamics. As this rapid growth occurs even in countries with high levels of vaccinations, the question arises as to their effectiveness. The smoothed daily number of new cases and deaths per capita and the ratio of these characteristics were used to reveal the appearance of new coronavirus strains and to estimate the effectiveness of quarantine, testing and vaccination. The third year of the pandemic allowed us to compare the pandemic dynamics in the period from September 2020 to January 2021 with the same period one year later for Ukraine, EU, the UK, USA, India, Brazil, South Africa, Argentina, Australia, and in the whole world. Record numbers of new cases registered in late 2021 and early 2022 once again proved that existing vaccines cannot prevent new infections, and vaccinated people can spread the infection as intensively as non-vaccinated ones. Fortunately, the daily number of new cases already diminishes in EU, the UK, USA, South Africa, and Australia. In late January - early February 2022, the maximum averaged numbers of new cases are expected in Brazil, India, EU, and worldwide. “Omicron” waves can increase the numbers of deaths per capita, but in highly vaccinated countries, the deaths per case ratio significantly decreases.

Highlights: Vaccinated persons can get and pass the new coronavirus variants. The probability of death is much lower for vaccinated persons.

The averaged daily numbers of new COVID-19 Cases per Capita (DCC) and Deaths per Capita (DDC) may indicate the effectiveness of quarantine, testing, vaccination, treatment, and also the virulence of coronavirus strains circulating in particular regions at some fixed periods of time. The DCC and DDC values can be calculated with the use of the accumulated number of Cases per Capita (CC) and Deaths per Capita (DC) and the simple smoothing procedure proposed in [1-3]. The CC and DC numbers are regularly reported by the World Health Organization, [4] and COVID-19 Data Repository by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU), [5].

Since we are already in the third year of the pandemic, it is reasonable to compare the DCC and DDC numbers for the same periods in 2020, 2021, and 2022 in order to find some seasonal and global trends. Since the influence of vaccinations in 2020 and early 2021 can be neglected, the comparison of the COVID-19 pandemic dynamics for the same period one year later enables us to reveal some influences of vaccination levels.

In [6] the DCC values for Argentina, Brazil, India, South Africa, Ukraine, EU, the UK, USA and the whole world for the period from March to August 2020 were compared with the corresponding values in 2021. In this paper we will compare the DCC, DDC, DDC/DCC values and vaccination levels in the same countries and Australia for the period from September to January in 2020-2021 and 2021-2022, and will try to reveal some trends and make some predictions.

The CC figures (per million) registered by JHU, [5] are shown in table 1 (August 25, 2020 - January 25, 2021) and table 2 (August 25, 2021 - January 20, 2022). The accumulated numbers of deaths per capita DC (per million) are shown in table 3 (August 25, 2020 - January 25, 2021) and table 4 (August 25, 2021 - January 20, 2022). We denote these values as Vj corresponding time moments tj measured in days. Similar to the approach proposed in [1-3], we will use the averaged CC and DC values which can be calculated with the use of smoothing