Question

how to know a person is suffering from AIDS​

Answer 1

AIDS is the end stage HIV infection. These are some of the symptoms that may present themselves when a person develops AIDS:

Chronic diarrhoea

Weight loss

Soaking night sweats

Kaposi's sarcoma

Cervical Cancer

Lymphoma

Tuberculosis

When a person is infected with HIV, his or her body's defence mechanisms will start to weaken. At the end stage of HIV infection, the individual is susceptible to "opportunistic infections". These are infections caused by viruses, bacteria and fungi that are usually incapable of penetrating healthy immune systems.

Answer 2

There will be some symptoms like loss of immune system fever vomiting fever vomiting  headache so we can say that the person was affected with AIDS