Pollen peril: how heat, thunder and smog are creating deadly hay fever seasons

Scientists say a complex mix of factors are making seasonal allergies worse for longer in many parts of the world - but why is it happening and is it here to stay?The first time it happened, László Makra thought he had flu. The symptoms appeared from nowhere at the end of summer in 1989: his eyes started streaming, his throat was tight and he could not stop sneezing. Makra was 37 and otherwise fit and healthy, a mid-career climate scientist in Szeged, Hungary. Winter eventually came and he thought little of it. Then, it happened the next year. And the next."I had never had these symptoms before. It was high summer: it was impossible to have the flu three consecutive years in a row," he says. Continue reading...