9 countries using the Chinese vaccines are investigated. These are Bahrain, Egypt, UAE, Chile, Uruguay, Brazil, Turkey, Mongolia and Indonesia, spanning the Middle East, South America and Asia regions.
The plot of Case Fatality Rate (%) vs Full Vaccination Rate (%) is shown for each country for the period from 1 Jan 2021 to 6 August 2021. The red curve shows the evolution of the CFR while the green area depicts vaccination rate. A windowed method for computing the CFR with a lag between the “Cases window” and “Deaths window” is adopted. The length of the window is 30 days with the “Deaths window” trailing behind the “Cases window” by 7 days. The need to consider time lag in computing the CFR is well-documented and has been elaborated in the literature [1,2].
Out of the 9 countries, 4 of them (Bahrain, Brazil, Turkey and Mongolia) show a distinct drop in CFR as vaccination rate increases. 3 of the countries (Egypt, Chile and Uruguay) show an increase in CFR while the last 2 countries (UAE and Indonesia) do not exhibit any distinct trend. The vaccination rates of the countries are enumerated below (red for those that exhibit upward trend, green downward trend, blue for no definite trend).
- Egypt: 1.75%
- Chile: 64.54%
- Uruguay: 65.41%
- Bahrain: 62.43%
- Brazil: 20.41%
- Turkey: 33.11%
- Mongolia: 60.86%
- UAE: 71.5%
- Indonesia: 8.12%
It’s to be noted that the CFR trend could due to a host of factors in addition to vaccination rate alone. These include the onset of the new Delta variant earlier this year, the public health capacity/quality of the countries considered, the pandemic control capability of the respective governments and the overall vaccination rate, among other factors. For example, strictly, Egypt and Indonesia should be excluded from the analysis since the vaccination rates are far lower than those of the other countries considered. In that case, out of the remaining 7 countries, 4 countries show a decreasing trend in the CFR and only 2 countries exhibit an increasing trend.
- Donnelly CA, Ghani AC, Leung GM, Hedley AJ, Fraser C, Riley S, et al. Epidemiological determinants of spread of causal agent of severe acute respiratory syndrome in Hong Kong. Lancet. 2003;361:1761–6.
- Wilson N, Kvalsvig A, Barnard L, Baker MG. Case-Fatality Risk Estimates for COVID-19 Calculated by Using a Lag Time for Fatality. Emerg Infect Dis. 2020;26(6):1339-1441. https://doi.org/10.3201/eid2606.200320
- World Health Organization (WHO). Estimating mortality from COVID-19. https://www.who.int/news-room/commentaries/detail/estimating-mortality-from-covid-19