First came the stink bugs, threatening the hazelnut harvest and offending the olfactory senses. Then came the Asian tiger mosquitoes, aggressive biters that can carry viruses including Zika and West Nile. The latest infestation to befall Istanbul is ticks, which have swarmed some neighbourhoods of Turkey’s biggest city and sent nearly 8,000 people to hospital with bites so far this year. Thirteen people have died.