For Costa Rica it is not necessary any mandatory vaccination.
The water is drinkable for 90% of the country and there is no danger in consuming raw fruits and vegetables or any other food.
There are no epidemics. Only in some areas of swamps and marshland you can meet with dengue (easily treatable without consequences as widely known).
The Costa Rican health system is considered the best of all of Latin America with European or American standards, the facilities are good and accessible to all, tourists and foreigners from around the world are entitled to emergency treatment at public hospitals without any difficulty or complications (of course if you do not have an insurance the service is a fee).
The main public hospitals are in the capital as Hospital San Juan de Dios and Hospital, Mexico are highly recommended for the quality and service offered, in Guanacaste in Nicoya and Liberia (30/50 minute drive from Tamarindo) there are a good hospital.
As a resident is required to pay to the CCSS (Caja Costarricense de Seguro Social) a monthly amount based on income and allows you to go to any public hospital to receive all the medical care and medication at no charge !! (Including foreigners).
To ensure greater safety and comfort is a recommended a private insurance in order to use the services of the various private hospitals present, hospitals luxury and high-tech with many medical specialists and highly qualified but very expensive.
The most important are located in the metropolitan area as a Hospital Cima, Clinica Biblica, The Catholic, and others.
In all tourist locality (including Tamarindo) are small health care facilities open 24 hours with ambulance that provide first aid or a simple generic medical advice, and usually there are specialists on certain dates by appointment.
Present throughout many dental centers at affordable prices and qualified for the good service, as well as ophthalmologists, testing laboratories, physical therapists, spas and anything else regarding the health care.