Delays in vaccine delivery 'not unexpected'

Vaccines are complicated to manufacture and so delays in delivering coronavirus vaccines are not unexpected, the chair of clinical pharmacology at the University of Newcastle in Australia has said.

Supply problems have been announced by AstraZeneca, provoking criticism from the EU after hearing it would receive a reduced number of vaccines.

Prof Jennifer Martin told BBC World News: "I guess the problem we have got this time is both the northern and southern hemispheres are wanting the vaccine all at once and there is a significant issue with need for this vaccine and it's really quite an urgent need."

Australia and New Zealand had been fortunate to have fewer Covid-19 cases so there was not the same acute need for vaccines as the UK, Europe and the US had, she added.