Human immunodeficiency virus, or HIV, is a virus that attacks the body’s immune system — specifically, white blood cells called CD4-positive (CD4+) T-helper cells.
When the immune system is weakened from AIDS, the body may have difficulty fighting off certain cancers or viral, fungal, or bacterial infections, and these conditions may prove fatal.
Signs and Symptoms of HIV/AIDS
There are three main stages of HIV infection, each with its own symptoms.
Stage 1: Acute HIV Infection
Within the first two to four weeks after HIV infection, about two-thirds of people will experience symptoms that feel like a really bad flu. As the immune system rallies to fight off the virus, fever may develop along with additional symptoms, such as sore throat, swollen glands, mouth sores, rashes, diarrhea, fatigue, headache, and muscle and joint pain.
Stage 2: Clinical Latency
If the infection goes undiagnosed or untreated, the immune system can bring the HIV level down some, but it can’t completely control or contain it; the virus is still active but multiplies more slowly, often without causing any symptoms. This is also called the clinical latency stage, or chronic HIV infection, and it can last up to 15 years.
Stage 3: AIDS
If a person goes for years without treatment for HIV, the next and final stage is AIDS.
- Sudden weight loss
- Recurring fever
- Night sweats
- Fatigue and weakness
- Swollen lymph glands
- Chronic diarrhea
- Sores in the mouth, anus, or genitals
- Blotches on the skin, under the skin, or inside the mouth, nose, or eyelids
- Neurological issues, including memory loss and depression
Learn More About Signs and Symptoms of HIV
Causes and Risk Factors of HIV/AIDS
HIV is spread by direct contact with certain body fluids from a person with HIV who has a detectable viral load. These fluids are:
- Semen (cum) and preseminal fluid
- Rectal fluids
- Vaginal fluids
- Breast milk
In the United States, HIV is mostly spread through sex, particularly anal and vaginal intercourse. People can also transmit HIV by sharing used injection equipment, such as syringes and other paraphernalia.
Mothers can spread HIV to babies during pregnancy, birth, and breastfeeding.
Learn More About HIV Transmission
Duration of HIV
Treatment and Medication Options for HIV
HIV Treatment Team
Side Effects of Medication
- Nerve problems
Learn More About Treatment for HIV
Prevention of HIV
There a number of strategies that can reduce your risk of becoming infected with HIV or greatly lower the odds that you will transmit the virus to an HIV-negative partner.
You can also reduce your risk of getting or transmitting HIV if you and your partner:
- Use HIV prevention medications, an approach called pre-exposure prophylaxis (PrEP)
- Take a combination of HIV medicines within 72 hours after you think you may have been exposed, an approach called post-exposure prophylaxis (PEP)
- Use condoms correctly and consistently
- Have a circumcised penis
- Never share drug injection equipment
- Limit your number of sexual partners
- Abstain from sex or choose less risky sexual behaviors, such as oral sex or mutual masturbation instead of anal or vaginal sex
- Get checked and treated for other sexually transmitted diseases
PrEP (Pre-Exposure Prophylaxis)
The FDA has approved two drugs to prevent HIV transmission: Truvada and Descovy. Both contain a medicine called emtricitabine combined with a version of a drug called tenofovir. Both have been found to be 99 percent effective in preventing sexual transmission of HIV when taken as prescribed by a doctor.
RELATED: How to Talk to Your Doctor About Preventing HIV
PEP (Post Exposure Prophylaxis)
If you think you may have been exposed to HIV — for instance if a condom broke or you have experienced a sexual assault — you can also take medicine after the event to prevent yourself from acquiring HIV. If you visit a healthcare provider and begin taking the medicine within 72 hours of exposure, it can prevent any HIV in your system from setting up shop and proliferating. Often it’s emergency rooms that provide PEP.
Research and Statistics: How Many People Have HIV/AIDS?
In 2019, close to 37,000 people were diagnosed with HIV in the United States, according to the latest figures available from the CDC. The annual number decreased by approximately 9 percent between 2015 and 2019.
The CDC further estimates that roughly 1.2 million people in the United States were living with HIV at the end of 2019, and that about 13 percent of those individuals were unaware they were HIV-positive.
Anyone can acquire HIV, but the prevalence of HIV is not the same in all communities and varies depending on social and demographic factors.
Conditions Related to HIV/AIDS
People with HIV or AIDS are more likely to get several kinds of cancers. In fact, some cancers are considered AIDS-defining conditions. They include:
- Kaposi sarcoma
- Non-Hodgkin lymphoma
- Cervical cancer
- Anal cancer
- Hodgkin disease
- Liver cancer
- Lung cancer
- Mouth and throat cancer
- Testicular cancer
- Squamous cell and basal cell skin cancers
Resources We Love
Favorite Organizations for HIV
Centers for Disease Control and Prevention (CDC)
The CDC works 24/7 to protect Americans from health, safety, and security threats. From statistics to treatment options, the agency provides comprehensive information about HIV and AIDS.
25 HIV Resources You Should Know About
This organization collaborates with departments across the federal government to offer HIV-related information. It’s a great source for up-to-date news about treatments and events.
Sponsored by the National Institutes of Health’s Office of AIDS Research, this site gives you access to the latest HIV/AIDS medical practice guidelines, clinical trials, and other research material. We like their glossary feature, which allows users to search different terms related to HIV and AIDS.
Greater Than AIDS
If you’ve got questions, Greater than AIDS has answers. The organization offers accessible HIV resources with more than 100 FAQs in both English and Spanish.
Favorite Online Support and Advocacy Networks
AIDS Healthcare Foundation (AHF)
For more than 30 years, AHF has been committed to providing cutting-edge medical care to the public, regardless of a person's ability to pay. AHF gives patients access to specialists, medication, and services.
Ryan White HIV/AIDS Program
If finances are a problem, this resource is for you. The program helps people with HIV and AIDS get medical care and other services even if they don’t have health insurance or money to pay for their healthcare. The Ryan White HIV/AIDS Program provides services to more than half a million people each year.
Foundation for AIDS Research (amfAR)
AmfAR is one of the world’s leading nonprofit organizations dedicated to the support of AIDS research, HIV prevention, treatment education, and advocacy. Since 1985, the organization has invested nearly $600 million in its programs. They host different events, and their office in Washington, DC, educates governing figures, the media, and the public about evidence-based policies that address HIV and AIDS.
American Academy of HIV Medicine’s Referral Link
Looking for an HIV specialist? The American Academy of HIV Medicine is a group dedicated to supporting HIV care providers. Their Referral Link feature provides you with the most comprehensive, up-to-date database of HIV doctors around the country.
Housing Opportunities for Persons With AIDS (HOPWA)
HOPWA is the only federal program dedicated to serving the housing needs of those living with HIV and AIDS. Under this plan, HUD makes grants to local communities, states, and nonprofits for projects that benefit low-income people with HIV and AIDS.
Center for HIV Law and Policy
Disclosing your HIV status can sometimes be socially and professionally risky. This organization provides information and resources about the law as it pertains to HIV. You can even search different laws in your state.
Clinical Info HIV/AIDS from the NIH
With three different options, Clinical Info is your go-to app source. The Glossary app lets you search for definitions of more than 700 terms. Or you can try the Drug Database app, which provides access to information about different medicines. The Guidelines app provides information about federally approved HIV/AIDS medical practice guidelines. You can download one, two, or all three.
The Life4me+ app helps establish communication between physicians and patients. It lets you organize your medication schedule and set private personalized reminders. You can also enter your tests results in the app, so you always have them on hand.
Favorite HIV Home Testing Resources
Need to take an STD test, but don’t want to leave your home? myLab Box offers kits that screen for STDs like HIV, chlamydia, gonorrhea, HPV, and more. Depending on the test, you’ll mail in a small sample of urine, a vaginal swab, or a prick of blood, and you’ll get your results in one to five days.
Testing couldn’t be any more convenient. This in-home HIV test is approved by the FDA and doesn’t require sending a sample to a lab. You can test yourself in the privacy of your own home with an oral swab. The kit gives you a result in 20 to 40 minutes.
Favorite HIV Blogs
The Body: HIV/AIDS Blog Central
Reading about others’ struggles and triumphs can help you in your journey. The Body’s network of blogs features first-person accounts from the HIV/AIDS community. The topics are diverse and designed to empower people with HIV.
Favorite Patient-Centered Annual Meetings
International AIDS Conference
The International AIDS Conference is the world’s largest conference on HIV and AIDS. It brings together scientists, policy makers, healthcare professionals, people living with HIV, funders, the media, and the community.
Ryan White HIV/AIDS Program (RWHAP) Clinical Conference
The annual RWHAP Clinical Care Conference provides cutting-edge scientific research, care, and treatment updates for clinical decision-makers who are responsible for the day-to-day care and treatment of people living with HIV.
Favorite Information on Nutrition for HIV
The Well Project
If you’re living with HIV, nutrition is vital for your long-term health and well-being. The Well Project, a nonprofit that focuses on women with HIV and AIDS, offers resources on how to incorporate the ideal foods for optimal health. You’ll find information on how to fight weight and muscle loss, keep your energy levels high, and minimize side effects from HIV medication.
HIV/AIDS Awareness Days
Over the years, HIV and AIDS have gone from stigmatized and little-discussed conditions to the subjects of a number of awareness campaigns, walks, runs, and fundraisers throughout the year. By participating in these activities, you help bring awareness to the experience of those living with HIV and AIDS.
Learn More About HIV/AIDS Awareness Month
Additional reporting by Deborah Shapiro.
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