- if you have not used a condom at all types of sexual intercourse (oral, vaginal, anal);
- if a condom has slipped off or has been torn;
- if you have had blood transfusion;
- if you have injected drugs with a shared syringe or drugs, made with shared tools.
- When the test has been taken too early and an organism has not had time to generate enough antibodies to be detected;
- at the AIDS stage, when an organism does not have protecting immune cells CD4+ any more.
On the whole, the sensitivity of contemporary tests, especially when the testing procedure takes place in a laboratory, almost eliminates the possibility of getting false results. Moreover, the testing rules presuppose repeating tests, which must be carried out twice – 3 and 6 months after the risk. This helps to avoid mistakes.
- sexual (through unprotected sex contact),
- parenteral (via blood, in particular, via blood transfusion, via the usage of “dirty” syringes, which contain the remnants of blood),
- vertical (from mother to child, prenatal – during pregnancy,
- intranatal – during labor and delivery,
- postnatal – during the period of breastfeeding through breast milk).