For 16 years and younger:
http://travel.state.gov/passport/get/minors/minors_834.html
For older than 16 years:
http://travel.state.gov/passport/get/first/first_830.html
Also, I have found the CDC website helpful regarding vaccinations and other health answers:
http://wwwnc.cdc.gov/travel/destinations/traveler/none/dominican-republic
Here is what it says about Vaccines for the DR:
All travelers
You should be up to date on routine vaccinations while traveling to any destination. Some vaccines may also be required for travel.
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|---|---|---|
| Routine vaccines |
Make sure you are up-to-date on routine vaccines before every trip. These vaccines include measles-mumps-rubella (MMR) vaccine, diphtheria-pertussis-tetanus vaccine, varicella (chickenpox) vaccine, and your yearly flu shot.
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Most travelers
Get travel vaccines and medicines because there is a risk of these diseases in the country you are visiting.
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| Hepatitis A |
CDC recommends this vaccine because you can get hepatitis A through contaminated food or water in the Dominican Republic, regardless of where you are eating or staying.
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| Typhoid |
You can get typhoid through contaminated food or water in the Dominican Republic. CDC recommends this vaccine for most travelers, especially if you are staying with friends or relatives, visiting smaller cities or rural areas, or if you are an adventurous eater.
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