And not all vaccines offer long term protection. The tetanus vaccine is a good example. It offers protection for only about ten years. Then a person must be immunized again.

In Nha Trang, the Institute of vaccine Research is producing safe vaccines for the country's most common diseases, including tuberculosis, tetanus and diphtheria, among others.

Objective: to observe clinical reactions and immune responses of combined vaccinations of mumps and hepatitis a, rubella vaccine, diphtheria-tetanus toxoids respectively.