The problem in India is that the poor and the rich don't necessarily live in very different sanitary conditions. In my experience, the situation is likely worse

The problem in India is that the poor and the rich don't necessarily live in very different sanitary conditions. In my experience, the situation is likely worse in poorer neighborhoods, but it is still very, very bad in rich neighborhoods. Unlike countries with similar economic development metrics, India is particularly filthy. So much so that, 'Swacch Bharat' aka 'Clean India' is a big effort by the current Government. This study from Johns Hopkins University, for example details how the prevalence mosquito-borne fevers does not follow income/class: www.jhsph.edu/news/news-releases/2015/burden-of-dengue-chikungunya-in-india-far-worse-than-understood.html To quote, "
Researchers estimated that on average, 23 percent of those who have not yet been infected become infected by dengue every year, corresponding to roughly 228,000 infections per year in Chennai alone. “This rate of infection is extremely high, almost three times higher than in areas of Brazil and Thailand where transmission was thought to be high,” says Rodríguez-Barraquer. They also found that the rate of infection in Chennai was similar in poor communities as in more affluent neighborhoods.

The research is believed to be the first to systematically measure dengue and chikungunya infection rates in India. “If you don’t understand the extent of the problem, you can’t address it,” she says.
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