It's been two decades and four Lok Sabha elections, but 50-year-old Sumariya Devi is yet to see politicians showing any interest in eradicating the curse of fluorosis that plagues her village in East Uttar Pradesh. A crippling disease caused due to the presence of excess fluoride in the ground water, it has left many among them with deformed teeth and bones. When the 1,000-odd residents of Rohiniwa-Damar go out to vote as part of the last phase of the Lok Sabha elections on May 19, they aren't likely to be brimming with hope. The Sonbhadra Lok Sabha constituency - one of the poorest and least-developed in the country - has never amounted to much for the political class.