I am sorry to hear that you are so worried.
In the situation you have described I do not think there is any risk of you being infected with an STI or HIV.
HIV and STIs are not passed through the casual contacts that occur in a doctors waiting area. HIV and STIs that are passed through blood can be transmitted through vaginal, anal and oral sex, sharing drug-injecting equipment and from a mother who is HIV positive to her newborn.
I cannot tell you what testing the people in this doctor’s office are doing. Blood test that we do in our clinics can test for HIV, Hepatitis A, B, C and Syphilis. Because this doctor is also a skin specialist he is likely doing other blood tests as well.
STIs that are found in blood would not pass if that blood came into contact with intact skin. These types of infections have to enter the blood stream and our skin provide very good protection against this.
In theory, If blood infected with these STIs is put directly onto an open wound there is a small chance of infection but this is not how we see these STIs being passed.
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