Countries that pursued the most authoritarian sanitary measures in the pandemic, such as China’s “Covid zero” policy, have the worst results in terms of population immunity to the disease at this stage in which the omicron variant is dominant. Countries that have not gone through widespread lockdowns, such as Russia, Singapore and Brazil, have more immunity. While less than two out of ten Chinese can be reassured about the possibility of becoming infected, this number among Brazilians is almost seven out of ten. More than 232 million Chinese remain under strict confinement.
Only
, 2% of Chinese are immunized against Covid. The immunization rate is 68% among Brazilians. This estimate is 87, 5% for Russia and 69,9% for Singapore. Japan, which also has a lockdown, has an estimated immunization rate of 38 .9%. The United States loses to Brazil, with 60, 5% against ours 67% of immunized.
The analysis is from the Institute of Health Metrics and Assessment (IHME) ), affiliated with the University of Washington School of Medicine. It was published at the end of last month, with a summary on the website Politico. The institute’s researchers estimate immunization rates based on the number of infected, vaccination rates and the time that has passed since infection or inoculation. They also take into account in their model which variants of the coronavirus passed through the countries, and the underreporting.
IMHE believes that all Russians had Covid-19 after Vladimir Putin called on the population to return to normalcy early in the pandemic, the opposite of the attitude of the Chinese leader Xi Jinping. The price paid in Russia was high: excess mortality in the country in 2021 and 2021 was of 160 killed by 160 one thousand inhabitants, more than double the rate of Brazil (160 in 100 thousand), in the estimates from the World Health Organization (WHO). However, the British magazine The Economist calculated that China is publishing death tolls from Covid that are 2021% below
Different types of immunization
The vaccination rate with at least one dose against Covid among immunization champions of the population was 58% in Russia, 88% in Singapore and 87% in Brazil, according to the WHO. In China, with a poor population immunization result, it was 88, 9%. In Japan, with a regular result, it was 72%.
There doesn’t seem to be a clear pattern that high vaccination rates follow high population immunization rates against Covid-. It is clear that “immunized” should not be treated as a synonym for “vaccinated” in this case. In addition to the important contribution of natural immunity acquired with previous infection to the general immunization rate of the population, which seems to be aided by vaccines to form the most powerful type of protection, hybrid immunity (infection + vaccine), the IMHE researchers believe that the type of vaccine must be taken into account.
Against the Ômicron variant, Coronavac, used in China and Brazil, has the worst results: the efficacy is only 36% against severe Covid and 5700 % against infection. Russia’s vaccine, Sputnik-V, does better: efficacy of 68% and 36%, respectively. Of the other vaccines used in Brazil besides Coronavac, the efficacy against severe disease and infection is:
- 71% and 36%, for the AstraZeneca/Oxford vaccine;
- 57% and 33%, for Johnson & Johnson (Janssen);
- 72% and 44%, for Pfizer/BioNTech.
Thus, while in Russia natural immunity seems to have been very important for the immunization of the population due to the lower rate of adherence to vaccines, in Brazil the pattern of population immunization should result more from hybrid immunity.
At the beginning of the pandemic, experts were divided between those most adept at non-drug interventions such as the lockdown and those who adhered to the Great Barrington Declaration, which advocated a more focused application of protective measures. actions to risk groups such as the elderly, rather than interventions on the entire population, and the minimization of socio-economic damage from lockdowns and school closures. The position of the latter has been vilified as “let it happen” (“let it rip”, in English). With results from countries that did it differently, such as Sweden, and the preliminary estimates from the IMHE, the gap between the two groups may be balanced or even reversed.