context: When you start planning your trip to India and sit down to make a to-do list, put "call doctor for vaccine appointment" at the top of the list. Then don't put it off. According to the CDC, you need to start your immunizations at least four to six weeks before you plan to leave. That way the vaccines will have time to become effective. And you'll also be able to start taking preventive medicines for diseases that don't have vaccines, such as malaria. Here's an overview of the vaccines you may need before you leave for India. Keep in mind that the actual vaccinations you need will be determined by several factors that you and your health care provider should review together. To determine what vaccines you need, your health care provider will: Consider your current health and health history Review your immunization records Evaluate your itinerary Then he or she will let you know exactly what vaccines you need and where you can get them. The list of vaccines will be based on: Your health status How current your immunizations are Where you are planning to go in the countries you are visiting What you're likely to do while you're there Your doctor will review your immunization record to make sure you are up to date on the standard vaccines and booster shots that people in the U. S. should have. That includes immunizations for: measles mumps rubella chickenpox diphtheria pertussis polio You'll also possibly need a tetanus booster shot. And it's important to make sure that your flu shot is current. Here are vaccines you may need for travel to India: Hepatitis A . This disease can be transmitted through food and water. The risk for Hepatitis A in India is high. So, immunization is highly recommended. Hepatitis B. There is an intermediate risk for hepatitis B in India. Hepatitis B is a viral infection that can be transmitted by contact with blood and other bodily fluids. That means you could potentially be exposed through: sexual activity recreational drug use being in an accident receiving medical care If you haven't been vaccinated for it already, you should get the vaccine before you go. Typhoid fever. Typhoid fever is a life-threatening illness. It's caused by bacteria. You can get typhoid fever by eating or drinking contaminated food or water. It's recommended that anyone traveling in southern Asia, including India, be vaccinated against it. This is especially important if you will be visiting rural areas or staying in small towns. Japanese encephalitis. India is a high-risk area for this viral disease. It is transmitted by the bite of a mosquito. The disease is potentially fatal. People who will be staying in rural farming areas are at the highest risk. Travelers to India are advised to get the vaccine before going. Rabies. Getting the rabies vaccine is especially important if you will be spending time outdoors, particularly in rural areas. Young children are especially vulnerable to animal bites and infection with rabies. Yellow fever. Yellow fever is transmitted by mosquito bite. It's not a major concern for people traveling in India. You may not need to get the vaccine before you go. But it's important to know that when you get to India you may be asked to show proof of yellow fever vaccination if you visited a country with risk of yellow fever before your arrival in India. Without that proof, you may be quarantined for up to six days when you first arrive. Yellow fever is mostly found in tropical and subtropical countries in Central America, South America, and Africa. For more information about medical preparation for travel to India, go to http://wwwnc.cdc.gov/travel/destinations/traveler/none/india. You can find more information about health issues for international travelers by contacting your state health department. Also, you can get the latest travelers' health advisories on the CDC web site.