Graphics in linked articles show the effluent of Indian wastewater treatment plants. Few public wastewater facilities can, or were designed to, remove antibiotics from our waste. They are designed for household waste, not industrial waste. Most antibiotics and other drugs pass straight through a typical wastewater plant unharmed. In the USA, Industrial PreTreatment is required for businesses that would otherwise discharge toxic or damaging substances to a public treatment plant. Usually the offending business builds, runs, and pays for pretreatment. Unless, of course, the "good ol' boy" system can unload the cost onto local residents.
America and India have the same problem; India just has more metric tons of it and far less regulation.
FYI: licensed wastewater operator (retired).