HIV (human immunodeficiency virus) is a virus that attacks the body’s immune system, specifically destroying white blood cells that help fight illness. If left untreated , it can severely weaken defenses and lead to AIDS . it is a virus that attacks the body white blood cells , which weakens the immune system and makes it hard to fight off everyday infections and diseases.

ROLE OF CD4 CELLS IN HIV

CD4 cells (T-helper cells ) act as the ‘’commanders’’ of the immune system by signaling other immune cells to fight off infections. HIV specifically targets ,enters, and destroy these CD4 cells, using them to make copies of itself, which progressively weakness the body defense against diseases .

STAGES OF HIV INFECTION

Without treatment , untreated HIV infection progresses into three primary stages :

STAGE 1: Acute HIV infection

• Timing: usually develops 2 to 4 weeks after contracting the virus.

• What happens: The virus multiplies rapidly and attack immune cells . viral load is very high , making a person very contagious

• Common signs: flu-like illness, including fiver, chills, rash, sore throat muscle ache and swollen lypmph nodes.

STAGE 2: chronic HIV infection

• Other names: Asymptomatic HIV infection or clinical latency.

• What Happens: The virus stays but reproduces at very low levels . it continues to slowly damage the immune system.

• Common signs: many people have no symptoms during this time. Without treatment , this stage last about 10 years or more ,but treatment can pause progression indefinitely .

STAGE 3: Acquired immunodeficiency syndrome (AIDS)

• What happens: the most severe stage, the immune system is badly damaged , and the CD4 cell count drops below 200 cells/mm3.

• Common signs: severe opportunistic infections and cancers appear because the body cannot fight them off. Symptoms include : rapid weight loss, lasting fever, extreme fatigue and swollen lymph glands.

CAUSES AND TRANSMISSION OF HIV

HIV is caused by retrovirus that attacks the immune system , specifically destroying CD4 white blood cells. It spreads only through specific body fluids –blood, semen, vaginal and rectal fluids, and breast milk –when they enter the bloodstream or touch mucus membrane.

CAUSES OF HIV

1. Viral infection : The virus targets CD4T-lymphocytes , copies itself inside them , and kills them , which slowly destroys the body’s ability to fight off disease.

2. Progression: left untreated, the continues loss of immune cells leads to advanced diseases or AIDS .

MAIN WAYS HIV IS TRANSMITTED

• Sexual contact: having unprotected vaginal or anal sex with an infected partner.

• Sharing equipment : sharing needles, syringes or drug-injection equipment .

• Perinatal spread: passing the virus from a parent to a baby during pregnancy , childbirth or breastfeeding.

• Contact with blood: though transfusion of unscreened blood or accidental needle sticks in medical settings .

SYMPTOMS OF HIV

A) Early symptoms

• Fever

• Fatigue

• Sore throat

• Skin rash

• Swollen lymph nodes

• Headache

B) Later- stage symptoms

• Persistent fever or night sweats

• Unexplained weight loss

• Recurrent infections

• Persistent diarrhea

• Severe fatigue

• Opportunistic infections

C) Risk factors

• unprotected sexual activity

• multiple sexual partners

• sharing needles or injection equipment

• presence of other sexually transmitted infections

• exposure to infected blood

• lack of access to HIV prevention and testing services.

HIV TREATMENT

ANTIRETROVIRAL THERAPY (ART)

• purpose of ART

The primary goal of Antiretroviral therapy (ART) is to reduce the human immunodeficiency virus (HIV) in the body to an undetectable level. This stops disease progression, preserves immune function, prevents transmission to others and allows individuals to live a long healthy life.

• Common classes of antiretroviral medicines

1) Nucleoside/ nucleotide reverse Transcriptase inhibitors (NRTIs)

Block reverse transcriptase enzyme , stopping HIV from copying its genetic code.

2) Integrase strand transfer inhibitors

Block the integrase enzyme so the virus cannot insert its DNA into human immune cells.

3) Non- Nucleoside Reverse Transcriptase inhibitors (NNRTIs)

Bind to and disable the reverse transcriptase enzyme differently than NRTIs .

4) Protease inhibitors: block the protease enzyme, preventing the virus, from making infections, mature copies.