If the qualifications were required for the course, you will need to withdraw your application and reapply in another year.
If you think you will want to reapply to the same universities and colleges in the future, explain what has happened to them in writing. You will find they are keen to offer help and advice.
If you are unable to take your examinations due to illness, let your universities and colleges know. Often your school or college will write on your behalf.