No certificate required, but a course of anti-malaria pills is recommended. For people with delicate digestive systems. It is advisable to use bottled mineral water, this is widely available. It is advisable to bring specific medicines. There are state operated facilities in all towns and cities and private consultants and specialists in urban areas.
All foreign nationals require visa to enter India.
However, there are some relaxations for Bhutanese and Nepalese nationals. Details and types of visa and the fee may be obtained from the Embassy of India. Tourist visas are issued for one month, six months or five years. Please consult your nearest Indian government mission to find out the latest details, fees etc. Tourist visas can be extended by three months at the foreigner's registration office in New Delhi, Mumbai, Calcutta and Chennai, or, with the Superintendent of Police at any District Headquarters.