The disproportionate case-fatality ratio of COVID-19 between countries with the highest vaccination rates and the rest of the world

Najmul Haider; Mohammad Nayeem Hasan; Javier Guitian; Rumi A Khan; David McCoy; Francine Ntoumi; Osman Dar; Rashid Ansumana; Md Jamal Uddin; Alimuddin Zumla; Richard A Kock

doi:10.1016/j.ijregi.2023.01.011

The disproportionate case-fatality ratio of COVID-19 between countries with the highest vaccination rates and the rest of the world

IJID Reg. 2023 Mar:6:159-166. doi: 10.1016/j.ijregi.2023.01.011. Epub 2023 Jan 26.

Authors

Najmul Haider^{1

2}, Mohammad Nayeem Hasan³, Javier Guitian¹, Rumi A Khan⁴, David McCoy⁵, Francine Ntoumi^{6

7}, Osman Dar⁸, Rashid Ansumana⁹, Md Jamal Uddin^{3

10}, Alimuddin Zumla^{11

12}, Richard A Kock¹

Affiliations

¹ The Royal Veterinary College, University of London, Hatfield, UK.
² School of Life Sciences, Keele University, Keele, UK.
³ Department of Statistics, Shahjalal University of Science and Technology, Sylhet, Bangladesh.
⁴ Division of Pulmonary Critical Care Medicine, Dell Medical School at University of Texas, Austin, Texas, USA.
⁵ Institute of Population Health Sciences, Barts and London Medical and Dental School, Queen Mary University of London, London, UK.
⁶ Congolese Foundation for Medical Research, Brazzaville, Republic of Congo.
⁷ Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany.
⁸ Chatham House Centre for Global Health Security, Royal Institute of International Affairs, London, UK.
⁹ School of Community Health Science, Njala University, Bo, Sierra Leone.
¹⁰ Department of General Educational and Development, Daffodil International University, Dhaka, Bangladesh.
¹¹ Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, UK.
¹² NIHR-BRC, University College London Hospitals, London, UK.

Abstract

Objectives: The global reported cumulative case-fatality ratios (rCFRs) and excess mortality rates of the 20 countries with the highest coronavirus disease 2019 (COVID-19) vaccination rates, the rest of the world and Sub-Saharan Africa (SSA) were compared before and after the commencement of vaccination programmes.

Methods: A time series model was used to understand the trend of rCFR over time, and a generalized linear mixed model was used to understand the effect of vaccination on rCFR.

Results: By 31 December 2022, an average of 260.3 doses of COVID-19 vaccine per 100 population had been administered in the top 20 vaccinated countries, compared with 152.1 doses in the rest of the world and 51.2 doses in SSA. The mean rCFR of COVID-19 had decreased by 69.0% in the top 20 vaccinated countries, 26.5% in the rest of the world and 7.6% in SSA. Excess mortality had decreased by 48.7% in the top 20 vaccinated countries, compared with 62.5% in the rest of the world and 60.7% in SSA. In a generalized linear mixed model, the reported number of vaccine doses administered (/100 population) (odds ratio 0.64) was associated with a steeper reduction in COVID-19 rCFR.

Conclusions: Vaccine equity and faster roll-out across the world is critically important in reducing COVID-19 transmission and CFR.

Keywords: COVID-19; Case–fatality ratio; SARS-CoV-2; Vaccine equity; Vaccine roll out; Variants of concern.

Grants and funding

MR/V028561/1/MRC_/Medical Research Council/United Kingdom