Question 1: HIV (Human Immunodeficiency Virus) is a virus that attacks the body's immune system, specifically the CD4 cells (T cells), which help fight infections. If untreated, HIV reduces the number of these cells, making the body more vulnerable to other infections and certain cancers, leading to AIDS (Acquired Immunodeficiency Syndrome).

Answer: HIV is a virus that attacks the immune system's CD4 cells, leading to AIDS if untreated.

Question 1: Define 'viral load' and explain its significance in monitoring HIV infection.

Answer: Viral load is the amount of HIV virus in a sample of blood; it indicates how actively the virus is replicating and helps monitor disease progression and treatment effectiveness.

Question 2: Describe the primary methods through which HIV is transmitted from person to person.

Answer: HIV is transmitted through unprotected sexual contact, sharing contaminated needles, from mother to child during childbirth or breastfeeding, and through blood transfusions with infected blood.

Question 1: If a patient's blood test shows a viral load of 50,000 copies of HIV per milliliter, what is the total number of viral copies in 2 milliliters of blood? (Use the formula: Total viral copies = Viral load per mL × volume in mL)

Answer: 100,000 viral copies

Question 2: A treatment reduces the viral load in a patient from 100,000 copies/mL to 5,000 copies/mL over a month. Calculate the percentage decrease in viral load.

Answer: 95%

Question 1: List three safety precautions that must be followed when handling blood samples in an HIV laboratory.

Answer: Use gloves and protective clothing, dispose of sharps safely, and sterilize surfaces and equipment regularly.

Question 2: Identify the variables in an experiment testing the effectiveness of a new HIV drug, including independent, dependent, and controlled variables.

Answer: Independent variable: Type or dosage of the drug; Dependent variable: Viral load or CD4 count; Controlled variables: Age, gender, initial viral load, and health status of participants.

Question 1: In a study, 200 individuals with HIV were monitored over 6 months. 150 individuals showed a decrease in viral load after starting antiretroviral therapy. What percentage of the participants responded positively to the treatment?

Answer: 75%

Question 1: Explain how antiretroviral therapy (ART) helps manage HIV infection and prevent progression to AIDS. (6 marks)

Answer: ART involves a combination of medicines that suppress the replication of HIV in the body, reducing viral load, preserving immune function, and preventing the development of AIDS. It does not cure HIV but helps individuals live longer, healthier lives.

Question 1: Discuss how modern technology, such as rapid diagnostic tests, has improved the detection and management of HIV/AIDS in developing countries.

Answer: Rapid diagnostic tests allow quick, affordable, and accessible HIV detection, enabling earlier treatment initiation, reducing transmission, and improving health outcomes in developing countries.