Repercussions of limited capacity Just over 500 million vaccines have now been administered. Big Pharma has estimated that between 9.5 and 13.5 doses will be required to achieve global herd immunity. Duke Global Health Innovation Center has developed a tracker to gather public data on vaccine manufacturing, with projections and current purchases set out in Figure 3.1. 12 bn doses are expected this year, with the main contributors being Oxford/AstraZeneca (3 bn), Pfizer/BioNTech (2bn) and Novavax (2bn). The COVAX initiative accounts for 1.3bn doses, aiming to distribute those to low- and middle-income countries by end 2021. However, initial roll-outs have been paused after India stopped AstraZeneca exports of 90m in March and April from the Serum Institute of India (SII) because of rapidly escalating domestic cases.
Figure 3.1 - Projections of global manufacturing capacity for COVID-19 vaccines
Source: Launch & Scale Speedometer
The sheer scale and complexity of the supply chains to support this level of vaccine production has two unexpected consequences: 1) Vaccines for other infections The Global Vaccine Market Report released in December 2019 estimated that 3.5bn vaccines of all types were administered in 2018. Demands from COVID19 will place extraordinary pressure on shared supply pathways and resources, and routine immunisation programmes are already being interrupted (over 50 in 100 countries according to WHO in the initial 6 months of the pandemic). This is particularly concerning for measles with its very high R0 (12-18) and potential for severe complications.
2) Monoclonal antibodies for cancer treatment COVID-19 has accelerated the shift in general vaccine production from chicken eggs to cell-based cultures in large stirred-tank bioreactors. The challenge is that such bioreactors are also used for growing monoclonal antibodies that allow precision medicine in the treatment of cancer and other conditions. A temporary bottleneck for now as next generation single use cubical tanks come on line.