Scientists at the national institutes of health are collaborating with the government of thailand to test the effectiveness of a new vaccine in preventing hiv infection among prostitutes. half the women receive the experimental vaccine and half receive an injection of salt water, and the women are then monitored for development of hiv infection. what kind of epidemiologic study is this?

Intervention epidemiologic study.

Explanation:

Intervention epidemology study may be defined as the study used to understand the effects of the medicine by the clinical trials. The result of the trail then compared with the other group.

The effectiveness of new vaccine has been measured to prevent HIV. The half women are given the experimental vaccine. This means the new medicine clinical trial has been done on half women. The women then monitored with the women that had received the salt water injection. This study clearly indicates the intervention epidemiologic study.

Thus, the correct answer is intervention epidemiologic study.