HIV destroys CD4 cells, which are responsible for keeping people healthy and protecting them from diseases and infections. As HIV gradually weakens the body’s natural defenses, signs and symptoms may occur.

Once HIV enters the body, it launches a direct attack on the immune system.
How quickly the virus progresses will vary by:
- a person’s age
- their overall health
- how quickly they receive a diagnosis
The timing of a person’s treatment can also make a huge difference.
HIV targets the types of cells that would usually fight off a virus such as HIV. As it replicates, it damages or destroys the infected CD4 cell and produces more virus to infect more CD4 cells. CD4 cells are also called T cells or helper cells.
Without treatment, this cycle can continue until the immune system is highly compromised, leaving a person at risk for serious illnesses and infections.
The final stage of HIV is stage 3 HIV, also known as AIDS. At this stage, the immune system is severely weakened, and the risk of contracting opportunistic infections is much greater.
However, not everyone with HIV will go on to develop AIDS. The earlier a person receives treatment, such as antiretroviral treatment, the better their outlook. Other treatments can help address the effects of HIV and AIDS on other systems of the body, such as blood pressure medications or creams for the skin.
The immune system helps prevent the body from acquiring the diseases and infections that come its way. White blood cells defend the body against viruses, bacteria, and other organisms that can make a person sick.
Early on, HIV symptoms may be mild enough to dismiss.
A few days after exposure to the virus, a person with HIV may experience a flu-like illness that lasts a few weeks. This is associated with the first stage of HIV, which is called the acute infection stage, or acute HIV.
Acute infection
An HIV-positive person may not have many serious symptoms during this stage, but there are usually large quantities of virus in their blood as the virus reproduces rapidly.
Acute symptoms can include:
- fever
- chills
- night sweats
- diarrhea
- headaches
- muscle aches
- joint pain
- sore throat
- rash
- swollen lymph nodes
- mouth or genital ulcers
Chronic HIV infection
The next stage is called the chronic infection stage. It can last for as long as 10 to 15 years. An HIV-positive person may or may not show signs or have symptoms during this stage.
As the virus advances, the CD4 count decreases more drastically. This can lead to symptoms such as:
AIDS
If untreated HIV advances to AIDS, the body becomes prone to opportunistic infections.
These infections include a herpes virus called cytomegalovirus (CMV). It can cause problems with the eyes, lungs, and digestive tract.
Kaposi sarcoma, another possible complication, is a cancer of the blood vessel walls. It’s rare among the general population, but it’s
HIV and AIDS also put a person at
HIV makes it hard to fight off respiratory problems such as the common cold and flu. In turn, an HIV-positive person may develop related infections, such as pneumonia.
Without treatment for HIV, advanced disease puts an HIV-positive person at an even greater risk for infectious complications, such as tuberculosis (TB) and a fungal infection called
The risk of lung cancer also increases with HIV. This is due to weakened lungs from numerous respiratory issues related to a weakened immune system.
According to 2024 research, lung cancer is more prevalent among people with HIV compared to people without it.
People with HIV are also
If a person has HIV with a low CD4 count, they’re also more susceptible to TB.
TB is an airborne bacterium that affects the lungs. It’s one of the
Since HIV affects the immune system, it also makes the body more susceptible to infections that can affect the digestive system.
Problems with the digestive tract can also decrease the appetite and make it difficult to eat properly. As a result, weight loss is a common side effect of HIV.
A
Another viral infection that affects the mouth is oral hairy leukoplakia, which causes white lesions on the tongue.
Salmonella infection is transmitted through contaminated food or water, causing diarrhea, abdominal pain, and vomiting. Anyone can get Salmonella, but people who have HIV are at higher risk for serious complications from it.
Consuming contaminated food or water can also result in a parasitic intestinal infection called cryptosporidiosis. This infection affects the bile ducts and intestines and can be particularly severe. It can cause chronic diarrhea in people with AIDS.
While HIV doesn’t generally directly infect nerve cells, it does infect the cells that support and surround nerves in the brain and throughout the body.
While the link between HIV and neurological damage isn’t completely understood, it’s likely that infected support cells contribute to nerve injury.
Advanced HIV can cause nerve damage, also known as neuropathy. This most commonly leads to pain and numbness in the feet and hands.
Small holes in the conducting sheaths of peripheral nerve fibers can cause pain, weakness, and difficulty walking. This condition is known as vacuolar myelopathy.
There are significant neurological complications of AIDS. HIV and AIDS can cause HIV-associated dementia, a condition that seriously affects cognitive function.
Toxoplasma encephalitis, caused by a parasite commonly found in cat feces, is another possible complication of AIDS.
Having a weakened immune system puts people with AIDS at an increased risk for inflammation of the brain and spinal cord due to this parasite. Symptoms include confusion, headaches, and seizures. Seizures can also result from certain nervous system infections.
- memory impairment
- anxiety
- depression
Stress caused by having HIV or AIDS can also cause mental health issues.
In very advanced cases, hallucinations and frank psychosis can occur. Some people may also experience headaches, balance or coordination issues, and vision problems.
One of the more visible signs of HIV and AIDS is on the skin.
A weakened immune response leaves a person more vulnerable to viruses such as herpes. Herpes can cause people to develop sores around their mouth or genitals.
HIV also increases a person’s risk for shingles. The reactivation of herpes zoster, the virus that gives people chickenpox, causes shingles. The condition causes a painful rash, often with blisters.
A viral skin infection called molluscum contagiosum involves an outbreak of bumps on the skin. Another condition, prurigo nodularis, causes crusted lumps on the skin as well as severe itching.
HIV can also make people prone to other skin conditions, such as:
HIV can result in a range of symptoms, from mild flu-like symptoms in the early stages to neurological symptoms if the condition progresses to AIDS.
Many of the effects described above are related to the immune system being continually compromised in the progression of HIV and AIDS.
However, many of these effects are preventable with antiretroviral treatment, which can preserve and repair the immune system.
A healthcare professional may recommend additional treatments, such as blood pressure medications or creams for the skin, to address the effects of HIV and AIDS on other systems of the body.