Well, I don't think there is any problem in allowing her to continue. Before going further, I would like to ask you the following:
- How did you come across her "eclipse disease/problem"? Is it that she recently fainted, and medically you were informed about her problem?
- From how many days/weeks has she been working with your company?
- How many times has she experienced fainting during her work period up to today?
- Did you ask her (either at the time of joining or later) to provide a "Medical Fitness Certificate"?
- What do your organizational policies say regarding this issue?
Rights and Responsibilities
Secondly, she has every right to work, and you must not object unless she is declared medically unfit for the job, which has not been determined yet. Therefore, you need to ask her to present her "Medical Fitness Certificate" (if not requested before) and allow her to continue her job. Also, you should not use phrases like "Is she able for INSURANCE JOB" as the work function does not matter in this context.
Social and Professional Duty
Furthermore, it is your social and professional duty to help her in this situation. While I understand it is not right to hide any medical problems from an employer at the time of joining, she must accept if the issue is serious. However, there is a mistake on your end if you did not ask for a "Medical Fitness Certificate" at the time of joining.