What does HIV do to the body?

When HIV enters the body, it begins by attacking the immune system, particularly attacking the CD4 cells that help you fight off infections. As the virus continues to multiply, the immune system works hard to respond.

During the early stage of infection, the body produces antibodies to try to fight the virus. This is part of the seroconversion process, when your immune system starts mounting its defences. These symptoms usually appear 4–6 weeks after infection, although not everyone will notice them.

After this initial stage, the virus stays active inside the body even if symptoms fade. These early symptoms may disappear for 10–15 years, but HIV continues to grow within your body. Over time, the immune system weakens, making it harder for the body to fight infections.

During the seroconversion process, the body’s immune response to the infection grows, which produces symptoms.

Flu-like symptoms

One of the most common symptoms is fever. Your body raises its internal temperature to create a hostile environment for any infections. You may also experience fatigue, swollen glands, muscle aches, and a sore throat.

Rash

A rash is another noticeable symptom during early HIV infection. It may appear on the chest, back, or face, and can look like flat red patches or small slightly raised areas. Not everyone will develop a rash, but it’s common enough that many people report it during the first few weeks of infection.

After the early stage of HIV infection, long‑term physical symptoms may take years to appear.

Skin issues

A common long‑term issue is the return of skin problems, such as rashes or irritation. As the immune system weakens, the body can become more susceptible to skin infections.

This can include:

• Bacterial infections like cellulitis, ecthyma, and impetigo
• Bacillary angiomatosis, a bacterial infection that causes hyperpigmented red or purple lesions
• Pitted keratolysis
• Increased number and severity of Herpes outbreaks
• Shingles (variella zoster virus)
• Molluscum contagiosum
• Yeast infections like pityrosporum folliculitis and pityriasis versicolor
• Parasitic infections like leishmaniasis and strongyloidiasis
• Cutaneous malignancies like squamous-cell and basal cell carcinoma or Kaposi’s sarcoma
• Psoriasis and eczema

Such problems aren’t just limited to your skin. HIV can cause recurring problems in the mouth, including:

• Canker sores in the mouth
• Cold sores caused by HSV 1
• Oral hairy leukoplakia (white plaques on the tongue caused by the Epstein-Barr virus)
• Thrush in the mouth
• Cracks on the corners of the mouth
• Cauliflower-like lumps in the mouth caused by HPV
• Periodontal disease (bleeding red gums and bad breath)
• Dry mouth

There are many other common symptoms of long-term HIV, such as weight loss and night sweats, and some less common ones, where almost any part of the body can be affected from the brain to the bones.

Over time, the immune system may struggle to fight even mild illnesses, which can lead to visible signs of poor health.

People may experience long‑lasting tiredness, swollen glands that do not go down, weight changes and sleep issues. These physical effects happen because HIV continues to damage the immune system cells that help keep the body healthy.

Starting treatment early can make a big difference in how HIV affects the body. Treatment helps stop the virus from damaging the cells that protect you from infections, giving the immune system a chance to recover.

Antiretroviral therapy (ART) stops the virus from multiplying. This helps protect CD4 cells, which keeps the immune system stronger for longer.

Over time, treatment can also reduce many of the physical symptoms linked to HIV. People who follow treatment correctly are less likely to develop ongoing skin problems, repeated infections, or long‑lasting tiredness. Because the immune system stays stronger, the body can fight illnesses more effectively and recover faster. This helps stop the internal damage from becoming visible on the outside.

ART side effects

For those who get treated for HIV, most people taking ART will remain completely well, but antiretroviral therapy can cause some other changes to the body, including:

• Weight gain/weight loss, either generalised or in some specific part of the body
• Rashes
• Loss of bone density
• Nausea and vomiting
• Mood changes, including anxiety and depression
• Damage to the kidney, liver, or pancreas
• Nerve damage (burning sensations in the hand or feet)
• High blood sugar and diabetes
• Hypersensitivity and allergic reactions

Contrary to what most people think, you don’t need to wait for symptoms to get tested for HIV.

Over 25% of individuals accessing clinic are over the age of 40, demonstrating that concerns about how prolonged viral infections might impact long-term immunity span well into adulthood.

A portion of patients deliberately combine their HIV tests with Hepatitis panels, highlighting a proactive awareness of how specific co-infections can jointly impact liver and whole-body health.

With consistent treatment, most people living with HIV can stay healthy and live full, active lives. Treatment helps the body stay strong, protects against long‑term health problems, and greatly reduces the chances of passing the virus to others. It changes HIV from a dangerous infection into a manageable condition, giving people control over their health and future.

HIV can affect the body in many different ways, both inside and out. Even when early symptoms fade, the virus can remain active in the body and continue to weaken the immune system if left untreated.

If you’re worried about HIV or think you may have been at risk, getting tested is the best way to know your status and protect your health. Better2Know offers fast, confidential, clinic‑based HIV testing across the UK, helping you get accurate answers and support when you need it most.

This article has been medically reviewed by Dr. Steve Chapman, 13/07/2026.

HIV can cause a wide variety of symptoms.