【明報專訊】When it comes to the research and development of vaccines against COVID-19, Europe, the US, China and Russia have their respective frontrunners. In the West, the Oxford-AstraZeneca and Pfizer-BioNTech vaccines were the first to undergo phase III clinical trials. The British media had high hopes for the "homemade" Oxford-AstraZeneca vaccine. AstraZeneca has always advertised its vaccine as non-profit. Each dose costs only a few US dollars, far cheaper than nucleic acid vaccines such as those by Pfizer-BioNTech and Moderna. It can be stored at normal refrigerator temperature and is thus suitable for widespread vaccination programmes in poor countries. That the vaccine is inexpensive but of good quality is its biggest selling point in its public relations campaigns. Some people have even described it as a "pandemic slayer" and regarded it as the hope for ending the global pandemic.