In India there is no waiting period or queuing up, either for diagnostic procedures or for treatment. Healthcare is not worth it when there is a prolonged waiting time.
After the initial diagnosis is done and the medical procedure decided upon, your surgery/intervention will be scheduled quickly. In a matter of days any medical procedure can be completed, unlike in some countries where even the diagnostic procedure could take many weeks or months.
Vaccinations and up-to-date immunizations are a safeguard for any international travel. However, please check with the doctor in your home country, any Government advisory and also the hospital in India as to what should be taken. The recommended vaccinations would normally be from the following list:
Diptheria Pertussis and Tetanus (DPT)
Measles, Mumps and Rubella (MMR)
Polio (Oral Polio Vaccine or Injectable Polio Vaccine)