Chennai: After wielding fogging machines, hand sprinklers and fists full of bleaching powder, the Tamil Nadu government, in a fresh attempt to kill the dengue buzz, has now launched an app.

Chennai and Mumbai are the only big Indian cities with an effective system to manage biomedical waste, whereas Delhi and other north Indian state capitals have a poor record, a study has found.

`Most Buildings Have Harvesting Systems, Maintenance A Problem'
Most buildings in the city are equipped with robust rainwater harvesting systems, says a survey by Metrowater.