An HIV infection has three potential stages, each of which has its own respective symptoms. People who begin HIV treatment soon after diagnosis and take treatment consistently every day are less likely to see their condition progress or become symptomatic. People who do not take HIV treatment will eventually experience disease progression and worsening symptoms, because HIV infection attacks the body’s immune system, making it ineffective.

Read on to learn about the three stages of HIV infection. This can help you understand what to expect if you’re living with HIV and learn how to take care of yourself.

Stage 1: Acute HIV Infection

Also known as the primary or acute phase of HIV, the acute (having symptoms that appear or change quickly) stage begins within two to four weeks immediately after infection. Soon after a person is infected, their body shows a normal immune response to the virus. As the immune system tries to fight HIV, it produces HIV antibodies (proteins designed to identify and neutralize HIV). During the acute phase, the virus rapidly makes copies of itself, and people are highly contagious.

Approximately half of people do not notice symptoms of HIV during the acute phase. Others experience flu-like symptoms such as:

• Swollen lymph nodes
• Headache
• Sore throat
• Fever
• Rash
• Muscle and joint aches
• Upset stomach
• Mouth sores

These symptoms may start between two and eight weeks after infection and may last for a week or two.

There’s a short period of time right after someone is infected with HIV, called the window period, during which the virus can’t be detected by a test. How soon an HIV test can detect the virus depends on the type of test. For example, a nucleic acid test has a window period of 10 to 33 days, whereas an antibody test has a window period of 23 to 90 days. If you think you may have been infected but your test comes up negative, it’s important to test again after the window period has ended.

Stage 2: Chronic or Latent HIV Infection

The chronic (ongoing) phase of HIV (also referred to as the clinical latent or asymptomatic stage) lasts for approximately 10 to 15 years in most people who do not take HIV treatment. In some people, the chronic period is much shorter, and HIV progresses more quickly to the next stage.

In people who consistently take HIV medicines — antiretroviral therapy (ART) — every day, the chronic stage can be prolonged by many decades, even lifelong. ART medications work to reduce a person’s viral load, or how many HIV particles are in the body. Maintaining a low viral load helps prevent disease progression and lower the risk of transmitting the virus to sexual partners. In fact, having an undetectable viral load long term (where it cannot be detected in the blood) means a person can’t transmit HIV through sexual means.

Some people notice persistently swollen lymph nodes during chronic HIV infection. Some may experience symptoms including:

• Fatigue
• Loose stools or diarrhea
• Weight loss
• Episodes of shingles
• Bouts of pneumonia

If a person has a tuberculosis germ in their body and isn’t taking HIV medications, the germ may become active. If a person has human papillomavirus (HPV) or herpes simplex infection in their body, they may experience outbreaks of these diseases. Some people may notice white marks in their mouth called oral candidiasis, or thrush. HIV continues to reproduce in the body, and it is possible to infect others. In those who are taking HIV treatment, it may be difficult to separate HIV symptoms from the side effects of medication.

Stage 3: AIDS

As the levels of HIV within the body begin to rise dramatically, the numbers of specific white blood cells, known as CD4 T cells, drop as the virus destroys them. AIDS is diagnosed when CD4 cell counts drop below 200 cells per cubic millimeter or when certain infections or types of cancer develop. People with AIDS who do not receive treatment usually die within approximately three years, although this number varies.

Symptoms of AIDS may occur on their own or may be related to other illnesses or underlying health issues associated with AIDS. These include:

• Extreme fatigue
• Rapid weight loss
• Night sweats or recurrent fevers
• Prolonged diarrhea (lasts more than one week)
• Pneumonia
• Swelling of the lymph nodes in the neck, armpits, or groin
• Discolored spots on the skin, eyelids, nose, and mouth
• Depression, memory loss, or other cognitive issues

Opportunistic Infections

During the final stage of HIV, the immune system has become ineffective. This leaves the body unprotected against many types of infection. People with AIDS can become seriously ill or even die from bacteria, viruses, or fungi that would otherwise not infect healthy people at all. This type of infection is known as an opportunistic infection.

Keep reading to learn about the opportunistic infections (and their most common symptoms) frequently seen in people with AIDS.

Pneumocystis Pneumonia

In the late 1980s, approximately 75 percent of people with AIDS were infected with pneumocystis pneumonia (PCP). Back then, treatment for HIV and prevention for PCP did not exist. Although PCP remains a significant opportunistic infection in people with AIDS today, rates of the infection are much lower because antiretroviral therapy strengthens the immune system, plus there are medications that can prevent PCP.

PCP is caused by a common fungus. In people with AIDS, PCP causes symptoms including:

• Fever
• Chest pain
• Trouble breathing
• Fatigue

Cytomegalovirus

Cytomegalovirus (CMV), a virus related to herpes, is present in most people, but it doesn’t cause illness except in those with compromised immune systems. In people with AIDS, CMV can infect the eye and cause blindness. It can also attack the lungs, heart, brain, or gastrointestinal system.

Mycobacterium Avium Complex

Mycobacterium avium complex (MAC) is a group of common bacteria that causes the following symptoms in people with AIDS:

• Abdominal pain
• Fever
• Night sweats
• Weight loss
• Anemia
• Fatigue

MAC can cause widespread illness in people with more advanced immunosuppression — including people with HIV who are not undergoing treatment.

Tuberculosis

Globally, tuberculosis is a leading cause of death in people with AIDS. TB most commonly affects the lungs, causing chest pain and coughing up sputum or blood. It also can infect other parts of the body and may result in symptoms such as weight loss, fever, and fatigue. People living with HIV are at higher risk for becoming infected with TB.

Candidiasis

Also known as a yeast infection or thrush, candidiasis is most commonly caused by the fungus Candida albicans. Although minor yeast infections can be a nuisance even in healthy people, candidiasis can affect immunocompromised people, such as those with AIDS, more severely. Candidiasis can cause:

• Difficulty swallowing
• A bad taste in the mouth (can be metallic)
• White patches on the inner cheeks and tongue, known as thrush
• Cracks and sores in the corners of the mouth
• Burning, itching, and thick white discharge from the vagina
• Chest pain when it affects the esophagus
• Pneumonia in the lungs

Toxoplasmosis

Toxoplasmosis is an infection by the microorganism Toxoplasma gondii, which can be found in cat or bird feces and undercooked meat. Toxoplasmosis is harmless and actually very common in healthy people. However, in people with AIDS, the infection can cause more serious illness and symptoms including headache, fever, confusion, seizures, and coma.

AIDS-Related Cancers

Some types of cancer are more common in people with AIDS because their compromised immune systems enable cancer to develop and grow quickly. The risks of these and other cancers decrease dramatically in people living with HIV who are taking HIV treatment.

Kaposi Sarcoma

A type of cancer that is related to a common herpes virus, Kaposi sarcoma causes darkened purple or brown spots on the skin. If Kaposi sarcoma spreads to the lungs or intestines, it can cause death, and the lesions can be quite painful and cause severe swelling.

Non-Hodgkin Lymphoma

Non-Hodgkin lymphoma (NHL) can develop in people with or without HIV, but certain types of NHL are more common in people who are HIV positive. Primary central nervous system (CNS) lymphoma begins in the brain or spinal cord. Symptoms of CNS lymphoma include confusion, memory loss, seizures, and paralysis of the facial muscles.

Invasive Cervical Cancer and Anal Cancer

Around 11,500 cases of cervical cancer are diagnosed every year in the United States. Cervical cancer is caused by the human papillomavirus. According to a study in The Lancet, women with HIV are more likely to develop abnormal cervical cells that can lead to cancer and have a higher risk of those abnormal cells progressing to invasive cervical cancer. Treatments for invasive cervical cancer do not work as well in women with HIV as they do in women who are HIV-negative. Symptoms of cervical cancer include abnormal vaginal bleeding, pelvic pain, unusual discharge, and painful urination.

Another HPV-related type of cancer that is more common in men and women with HIV is anal cancer. Around 28 percent of men and 1 percent of women with anal cancer also have HIV, according to research in Surgical Oncology Clinics of North America. Symptoms of anal cancer include a growth in the anus, along with anal bleeding, itching, and pain. HPV vaccines are available to help prevent the development of these cancers.

What Are Early Signs of HIV Infection?

Some people do not notice any symptoms in the weeks or months after being infected with HIV. In fact, roughly half of people infected with HIV do not experience symptoms. Others notice swollen lymph nodes or a period of flu-like symptoms during the first stage of HIV.

What Prevents the Progression of HIV?

Treatment for HIV is one of the best ways to prevent the progression or moving through the stages of HIV. Testing and early treatment significantly slows down the virus and therefore keeps the immune system strong. Although HIV treatment may have side effects, the vast number of options allows most people to find medications that they can tolerate so that they may live relatively normal lives.

Talk With Others Who Understand

On myHIVteam, the social network for people with HIV, more than 40,000 people come together to ask questions, give advice, and share their stories with others who understand life with HIV.

Have you or a loved one been diagnosed with HIV? Share your insights in the comments below, or start a conversation by posting on myHIVteam.