Inoculation or testing requirements are spreading nearly as fast as the Delta variant. But it is not clear they will actually drive more people to get vaccinated. A broad semiconductor shortage has hit plenty of industries; we examine supply-chain subtleties that have made it particularly bad for carmakers. And why Mumbai is suffering from a plague of snakes.

For full access to print, digital and audio editions of The Economist, subscribe here www.economist.com/intelligenceoffer