Mexico: Russia's Sputnik V shortages mean limited 2nd doses

Mexican authorities say Russia has been having so many problems producing second doses of its Sputnik V coronavirus vaccine that there won't be enough to give people who got the first dose a second shot

MEXICO CITY -- Russian authorities have been having so many problems producing second doses of their Sputnik V coronavirus vaccine that Russia probably will be unable to supply enough to people who already got the first dose, Mexican officials said Monday. It's the latest account of production problems for Sputnik V, which the Russian government has been promising to other countries but has not been able to supply in sufficient quantities. Sputnik is unusual among coronavirus vaccines in that the two doses are different and not interchangeable. The Russian vaccine uses a modified version of the common cold-causing adenovirus to carry genes for the spike protein in the coronavirus as a way to prime the body to react if COVID-19 comes along.