A swarm of worries buzzes inside my head as I head for the airport at 3am. I&rsquom hoping to reach Shergarh, a tented camp in the heart of Madhya Pradesh&rsquos tribal belt, by 5.30 p.m the same day. But the prospect of four nights with man-eating mosquitoes, flimsy canvas tents and no air-conditioning in tiger country has got my sweat glands working overtime.