What’s the difference between HIV and AIDS? What are PrEP and PEP? Here are 30 questions, answered, for the 30th anniversary of World AIDS Day.
People around the world on Saturday will observe the 30th annual World AIDS Day, an event aimed at spreading awareness of the HIV/AIDS epidemic.
To mark the 30th anniversary of the world’s first global health day, here are 30 frequently asked questions, myths, facts and figures surrounding HIV and AIDS throughout the world.
- What do HIV and AIDS stand for?
HIV stands for human immunodeficiency virus. AIDS stands for acquired immunodeficiency syndrome.
- What’s the difference between HIV and AIDS?
HIV is a virus that can lead to AIDS. AIDS is the last of the three stages of HIV infection.
According to the Centers for Disease Control and Prevention, people in the first stage, acute HIV infection, experience a flu-like illness within 2 to 4 weeks after infection. It can last a few weeks. People in this stage have large amounts of the virus in their blood, and so are more likely to transmit the infection.
The second stage, clinical latency, marks a period where the virus is active but reproduces only at low levels, HIV.gov says. People in this stage might not experience symptoms, but can still transmit HIV to others. This stage can last decades, depending on treatment, but can also be shorter.
AIDS, the third stage, leads to the most severe illnesses because the virus damages the immune system over time, the CDC says. On average, people with AIDS who don’t get treatment survive three years, according to the CDC.
Treatment at all three stages can prevent or slow symptoms and reduce the risk of transmission, the CDC says.
- How do you know if you have HIV or AIDS?
Testing is the best way to determine whether you have HIV, but symptoms can occur before HIV shows up on a test. Some experience flu-like symptoms – including fever, chills, rash, night sweats, muscle aches, sore throat, fatigue, swollen lymph nodes or mouth ulcers – within two weeks of infection.
- How does HIV make you sick?
HIV attacks your immune system by reducing CD4 cells, or T cells, making it harder to fight other infections.”Over time, HIV can destroy so many of these cells that the body can’t fight off infections and disease,” according to HIV.gov.
According to HIV.gov, the condition becomes AIDS when T cell counts drop below 200 cells per cubic millimeter of blood, or certain AIDS-related complications such as severe infections appear.
- How is the virus transmitted?
A person can become infected with HIV only through certain activities in which they come into contact with certain bodily fluids.
Blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids and breast milk can transmit HIV, according to the CDC.
“These fluids must come in contact with a mucous membrane or damaged tissue or be directly injected into the bloodstream (from a needle or syringe) for transmission to occur,” the CDC says.
Unprotected anal or vaginal sex with someone who has HIV is one of two main ways the virus is spread in the United States, according to HIV.gov. Use of a contaminated needle or syringe is the other.
A mother may pass the virus on to her child during pregnancy, birth or breastfeeding. It can also be contracted by being struck by an item contaminated with HIV. Other rare but possible ways to spread HIV can be found here.
- Can saliva or mosquitoes spread HIV?
No. HIV cannot be passed on through saliva, sweat or tears unless blood from a person with HIV is mixed in. That means touching, sharing bathrooms, kissing and other activities won’t spread the virus. Bugs such as mosquitoes and ticks also can’t spread it.
- Can HIV be transmitted by giving blood?
The CDC says contracting HIV in a health care setting is “extremely rare.” During the early years of the HIV crisis in the 1980s, cases of infection by blood transfusion were more common, according to HIV.gov, but “rigorous testing” today has greatly reduced the risk.
The National Heart, Lung and Blood Institute says the risk of HIV transmission through a blood transfusion is lower than that of being killed by lightning.
You can’t get HIV by giving blood, either, the CDC says.
Indonesian medical students light candles during a vigil commemorating World AIDS day in Surabaya, East Java, Indonesia, 2015.
- Can you get HIV again if you already have HIV?
Yes. HIV superinfection occurs when a person with HIV is infected with a different strain of the virus, according to the CDC. Effects vary, and some people can contract a strain that is resistant to the treatment they’re already taking, the CDC says, but “a hard-to-treat superinfection is rare.”
- How many people around the world have HIV?
According to the United Nations, 36.9 million people were living with HIV around the world in 2017. Of those, 35.1 million were adults and 1.8 million were children. The CDC estimates that 1.1 million people in the United States were living with HIV by the end of 2015. Fifteen percent didn’t know they were infected.
- How many people were newly infected with HIV in 2017?
Worldwide, 1.8 million people, according to the United Nations. In the United States, 38,739 people were diagnosed with HIV, according to the CDC.
- How many people died last year from HIV/AIDS-related illnesses?
Worldwide, 940,000 people, the United Nations says. In the United States, 15,807 people with an HIV diagnosis died in 2016. The CDC says those deaths could be from any cause.
- How have the numbers of cases and deaths changed since the HIV/AIDS epidemic began?
Since the epidemic began, 77.3 million people have been infected with HIV and 35.4 million have died from HIV/AIDS-related illnesses.
According to the World Health Organization, the 940,000 who died from HIV/AIDS in 2017 worldwide is a 52 percent drop from 2004 and a 34 percent drop from 2010.
According to U.N. data, the 1.8 million new diagnoses in 2017 was a 56 percent drop from the 2.8 million in 2000.
- When did the HIV/AIDS epidemic begin?
U.S. scientists found the first clinical evidence for the disease that would become known as AIDS in 1981, according to the United Nations. Chimpanzees in Central Africa have been identified as the source of HIV in humans. Their version of the virus, called SIV, was likely transmitted to humans and then mutated, the CDC says. HIV has existed in the United States since the mid- to late 1970s.
- Have cases increased amid the opioid crisis?
Concern is growing that opioid users sharing needles could cause an increase in HIV cases.
In 2015, Scott County, Indiana, suffered an outbreak of 181 HIV diagnoses linked to opioid use, according to the Kaiser Family Foundation.
According to CDC data cited by the Kaiser Family Foundation, the share of HIV infections in the United States tied to intravenous drug use declined from a high of 40 percent in 1990 to only 6 percent in 2015. The share spiked in 2015, largely due to the Indiana oubreak.
Data suggest the number dropped back to pre-2015 levels the next year.
- Are some demographics more at risk than others?
Gay and bisexual men are the most affected population in the United States, the CDC says.
Sixty-six percent of new HIV diagnoses in 2017 came from male-to-male sexual contact, according to the CDC.
Twenty-four percent came from heterosexual contact; 70 percent of those diagnosed were women.
Forty-three percent of the people diagnosed in 2017 were black or African-American. Twenty-six percent were white and 26 percent were Hispanic or Latino.
- What stigmas exist surrounding HIV/AIDS?
Fear around HIV and AIDS has allowed false information to spread and discrimination against some people to grow.
Discrimination based on sexuality, gender, drug use, sex work and economic status, among others, can greatly harm people who have HIV, the United Nations warns. People with HIV who perceive high stigmas are less likely to seek treatment immediately. Stigma can also discourage people from getting tested or disclosing their infections.
In the United States, there are legal protections aimed at preventing discrimination against people with HIV.
- Can HIV/AIDS be treated?
Yes. People with HIV can take a series of drugs, called antiretroviral therapy, or ART, that slows the virus from progressing, keeps them healthy for years and drastically reduces their likelihood of spreading the virus, the CDC says.
- How does ART work?
Antiretroviral therapy, which typically uses three drugs, is aimed at reducing a person’s viral load – the level of HIV in the blood.
The combination of drugs can “maximally suppress the HIV virus and stop the progression of HIV disease. ART also prevents onward transmission of HIV,” the World Health Organization says.
If the viral load remains undetectable, “you have effectively no risk of transmitting HIV to an HIV-negative partner through sex,” the CDC says. The CDC says people can reach an undetectable viral load within six months. But missing a dose can increase the load and the risk of transmitting HIV.
- What is the average life expectancy with treatment today?
An HIV or AIDS diagnosis 30 years ago often meant one to two more years of life, according to HIV.gov. With treatment, that’s changed.
“Today, someone diagnosed with HIV and treated before the disease is far advanced can live nearly as long as someone who does not have HIV,” the CDC says.
“Life expectancy in patients starting ART has increased by about 10 years during the ART era,” researchers reported last year in The Lancet. Their life expectancy does remain lower than the rest of the population.
- Is there a cure?
Not yet. Researchers are working toward a cure. If a cure were to be found, it’d likely take one of two forms, according to the National Institute of Allergy and Infectious Diseases.
Viral eradication would mean HIV was eliminated from a patient’s body. The approach would involve “prodding the virus out of its latent state so that an enhanced immune system or administered therapies can target and eliminate HIV-infected cells,” the NIAID says. Researchers are also studying gene mutations in certain people whose immune cells resist HIV.
A functional cure, or sustained ART-free remission, would mean that HIV was not eliminated, but rather suppressed to a point at which daily medication would no longer be longer required.
- Who is Timothy Brown?
Volunteers unfurl a section of the AIDS memorial quilt on the lawn of the Clinton Presidential Library in Little Rock, Ark., in observance of World AIDS Day, Dec. 1, 2009.
Timothy Brown, also known as the Berlin patient, is sometimes considered the first person cured of HIV. Brown, an American living with HIV in Berlin, was being treated for leukemia and required a bone marrow transplant, according to the National Institute of Allergy and Infectious Diseases. His donor had a genetic mutation for a protein called CCR5.
“CCR5 exists on the surface of human immune cells, and HIV uses this protein to enter and infect cells,” the institute says. “When CCR5 is dysfunctional or absent because of a defect in the gene that codes for it, HIV no longer has an easy way to infect immune cells.”
As a result of the transplant, Brown’s leukemia was cured, and no HIV infection was found. Physicians reported the case study in the New England Journal of Medicine in 2009. But bone marrow transplants are intensive, the institute says, and physicians haven’t been able to successfully replicate Brown’s results.
- Is there a vaccine?
No, but there have been a number of developments. The National Institutes of Health opened the first clinical trial with 138 healthy, HIV-negative volunteers in 1987, according to the National Institute of Allergy and Infectious Diseases.
In 2016, the NIH announced a vaccine-efficacy trial in South Africa of 5,400 people, the largest in the country’s history. Researchers are building on a 2009 success in Thailand, where for the first time ever a vaccine showed modest success in preventing HIV infections.
- What are some common prevention methods?
The CDC advises abstinence from sex, reducing the number of sexual partners and using condoms correctly every time you have sex as ways to reduce the risk of HIV exposure through sex. Using only sterile needles, and never sharing them, also reduce risk.
- What is PrEP and how effective is it?
Pre-exposure prophylaxis (PrEP) is daily medicine for HIV-negative people who are at high risk of getting HIV. According to the CDC, it can reduce the risk of getting HIV through sex by 90 percent and through injection by 70 percent.
PrEP is not a vaccine and should not be used instead of condoms and sterile needles, the CDC warns.
- What is PEP and how effective is it?
Post-exposure prophylaxis is for an emergency: Possible exposure in the past 72 hours. “The sooner you start PEP, the better,” the CDC says. “Every hour counts.”
PEP consists of antiretroviral (ART) medicines, and if prescribed and taken correctly (usually once or twice a day for 28 days), it can be effective, though not 100 percent, at preventing HIV, the CDC says. But PEP should not be taken every time you have sex without a condom and only in emergencies, the CDC says.
- Should I get tested for HIV?
Peter Njane, a Kenyan homosexual man and the Director of the homosexual rights group Ishtar, smiles at the group’s booth during an event organized by…
The CDC recommends everyone from ages 13 to 64 get tested at least once.
People at greater risk of infection, such as sexually active gay or bisexual men, people who have had sex with an HIV-positive partner, people who have shared needles and sex workers, among others should get tested more often.
The CDC recommends testing once a year for people engaging in these higher-risk behaviors. For sexually active gay and bisexual men, the CDC says testing every three to six months is beneficial.
If you are pregnant, and even if you are in a monogamous relationship, the CDC recommends testing to be sure and to reduce the risk of transmitting HIV to your child or partner. The sooner a pregnant woman starts treatment, the less likely she is to transmit HIV to her child.
- How do I get tested?
Most HIV tests involve blood or oral fluid. Clinics, hospitals, community health centers and many other locations provide HIV testing. Home testing equipment is also available.
HIV does not always show up right away in a test. Your body and the test type determine how long HIV can take to be detected. Here’s a useful guide from the San Francisco AIDS Foundation on testing windows.
For more information on local testing sites, call 1-800-CDC-INFO (1-800-232-4636) or
- What is World AIDS Day?
The World Health Organization first declared World AIDS Day in 1988. It was the first global health day. Observed each year on Dec. 1, the day is intended to raise global awareness of the fight against HIV, support for people with HIV and remember those who have died from HIV/AIDS-related illnesses.
- How can I help on World AIDS day?
Donating money for various organizations fighting HIV/AIDS, attending a World AIDS Day event or simply showing solidarity by wearing a red ribbon are all ways to help in the fight against HIV/AIDS.
According to UN data, $4.8 billion was available for low- to middle-income countries to fight AIDS in 2000. By 2017, that number was $21.3 billion.
- What do the red ribbons signify?
The red ribbon was created in 1991 by artists in New York working to increase awareness of HIV/AIDS. The artists saw the red ribbon as an easy-to-copy way to show compassion for those living with HIV, given the stigma surrounding it.
“They chose red for its boldness, and for its symbolic associations with passion, the heart and love,” according to World AIDS Day organizers.