CAIE IGCSE Biology 16.6.3 HIV Infection May Lead to AIDS
Practise stating the relationship between HIV infection and AIDS accurately without treating progression as immediate or certain.
- Syllabus
- 2026–2028
- Course
- Biology 0610
Practise stating the relationship between HIV infection and AIDS accurately without treating progression as immediate or certain.
Fig. 4.1 is a diagram of a virus.

Fig. 4.1
The human immunodeficiency virus (HIV) infects and destroys lymphocytes.
The number of lymphocytes in the blood of a person infected with HIV was measured over a period of 84 months.
The results are shown in Fig. 4.2.
number of lymphocytes per mm3 of blood

Fig. 4.2
Outline the consequences of the changes in the number of lymphocytes for the health of the person infected with HIV.
any four from: fewer antibodies (produced by lymphocytes) ;
decrease in immunity / inefficient immune system ; fewer memory cells ; any role of antibodies or lymphocytes (that will be impacted by fewer
lymphocytes) ;
develop AIDS ; example of (secondary) infection / disease / pathogen that may result from reduced number of lymphocytes ;