Oxford-AstraZeneca COVID-19 vaccine (AZD1222) is ideal for resource-constrained low- and middle-income countries

The safety and efficacy of coronavirus disease 2019 (COVID-19) vaccine in older adults have been eagerly anticipated owing to the 23fold greater risk of death due to COVID-19 in adults over 65 years of age [1]. Maheshi Ramasamy and colleagues [2] have recently presented the safety and immunogenicity of AZD1222 (previously ChAdOx1 nCoV-19), the COVID-19 vaccine candidate of AstraZeneca/Oxford, including adults aged 70 years and more. The vaccine seems to be better tolerated in older adults, exhibiting similar immunogenicity, irrespective of age, following the booster dose [2]. The inclusion of older adult populations in the vaccine trials help to understand how health status and frailty can influence vaccine efficacy, safety, immunogenicity, and reactogenicity in older adults [3]. The plan of AstraZeneca to expand their manufacturing capacity to 3 billion doses in 2021 is a major step in attaining 100% global vaccination coverage [4]. This correspondence aims to analyze the major COVID-19 vaccines developed by AstraZeneca/Oxford, Pfizer/BioNTech, and Moderna, in terms of safety, efficacy, cost, storage, and transportation.