Patient becomes severely immune deficient in this period t lymphocytes or cd4 count less than 200 into 10 to the power 6 per litre while normal cd4 count is more than 900 into 10 to the power 6 per litre and now this condition is called full-blown AIDS. The person suffering from full-blown AIDS becomes vulnerable for opportunistic infections which appear when immunity becomes weak like tuberculosis by mycobacterium avium ,Candidiasis of mouth in oesophagus by fungus candida albicans, pneumonia by fungus pneumocystis carnaii, cancer of skin and lymph nodes (kaposi sarcoma), encephalitise by toxoplasma gondii (protozoan).

Full blown AIDS, people have very low count of T-cells and it is kinds of cancer. The third stage of HIV in full blown AIDS.