Being HIV-positive means a blood or oral test found evidence of HIV, a virus that attacks the immune system CDC. It can't be cured, but it's now a manageable, lifelong condition. With consistent treatment, people live near-normal lifespans and don't transmit the virus to sex partners once their viral load is undetectable.
in 2023
≈723,000 — U=U
| Item | Value |
|---|---|
| New diagnoses | 38,800 — in 2023 |
| Living with HIV | 1.12 million |
| Virally suppressed | ~65% — ≈723,000 — U=U |
| On PrEP | 381,000 |
How HIV is tested
HIV testing looks for one of three things: the virus's genetic material, a viral protein called the p24 antigen, or the antibodies your immune system makes in response. Which one a test detects determines how early it can catch an infection CDC HIV Testing.
- A nucleic-acid test (NAT) measures the actual virus in your blood. It's the earliest and most sensitive, and it's also what's used to measure viral load once someone is in care.
- A fourth-generation antigen/antibody lab test checks for both the p24 antigen and HIV antibodies from a drawn blood sample. This is the workhorse screening test in most clinics.
- Antibody-only tests — including the finger-stick rapid tests and oral-swab kits — look only for antibodies, so they take the longest to turn positive.
The sample is either a small blood draw, a finger-stick drop of blood, or a swab of fluid from your gums. For a deeper breakdown of which test catches HIV when, see our guide to hiv testing.
When to test after a possible exposure
Every HIV test has a window period, the gap between exposure and when the test can reliably detect infection. Testing too early can give a falsely reassuring negative. By test type:
| Test type | What it detects | Detection window after exposure |
|---|---|---|
| Nucleic-acid test (NAT) | The virus itself | 10–33 days |
| Antigen/antibody (4th-gen) lab test | p24 antigen + antibodies | 18–45 days |
| Antibody / rapid / at-home test | Antibodies only | 23–90 days |
A negative result is only conclusive once you're past the window for the test you used and you had no new exposure during that time. If a test is negative but you're still inside the window, you'll need to retest later. Our page on when to test after exposure walks through the timing test by test, and the hiv testing hub explains why.
One exception overrides all of this. If you think you were exposed in the last few days, don't wait to test. Post-exposure prophylaxis (PEP), a 28-day course of HIV medicine, has to start within 72 hours to work CDC PEP. Take this to urgent care or an ER today; don't plan to test next week.
Who should get screened
The U.S. Preventive Services Task Force gives HIV screening a Grade A recommendation: everyone ages 15 to 65 should be tested at least once, and younger or older people outside that range who have risk factors should be tested too USPSTF Grade A. A one-time test is the floor.
- People at increased risk — including those with new or multiple partners, anyone with another STI, men who have sex with men, and people who inject drugs — should test at least once a year, and more often if exposures are ongoing.
- Everyone starting or continuing PrEP needs a confirmed HIV-negative test. PrEP medicines alone can't suppress an established infection, and using them with undiagnosed HIV can breed drug resistance.
- Anyone with flu-like symptoms a couple of weeks after a risky exposure should test promptly — more on that below.
HIV isn't evenly spread across the country. Diagnosis rates cluster in the South and the capital — Washington DC, Georgia, Florida, and Louisiana led the nation in 2023 — and roughly 38,800 people were newly diagnosed that year CDC AtlasPlus, 2023. Of the estimated 1.12 million Americans living with HIV, about two-thirds are virally suppressed, so many who could benefit from treatment aren't yet in care.
What getting tested is actually like
A rapid test is quick: a finger-stick or an oral swab, then results in minutes while you wait. A lab antigen/antibody test means a standard blood draw with results back in a day or several. Health departments and many community clinics offer HIV testing free, and at-home kits let you swab in private — just respect the window period, since at-home tests are antibody-only and turn positive latest.
Where you test affects cost, turnaround, and whether confirmatory testing is built in. You can get tested through several routes, and it's worth taking a minute to compare testing providers before you book. A common mistake is treating early flu-like symptoms as proof either way. Symptoms can't confirm or rule out HIV; only a test can.
Reading your results
A negative result past the window, with no exposure during it, means you don't have HIV. If you're still inside the window, it means "not yet detectable," so retest after the window closes. A reactive (preliminary positive) rapid or screening test is never the final word; it's always followed by a confirmatory test before a diagnosis is made, because screening tests occasionally flag people who turn out not to have HIV.
If you had a real risk recently and feel symptoms coming on, take them seriously. About 90% of people develop flu-like symptoms 2 to 4 weeks after infection — fever, sore throat, swollen glands, rash — exactly when viral load peaks above a million copies per milliliter and the virus is most transmissible hiv.gov. This acute stage is easy to mistake for an ordinary bug, which is part of why it spreads. Men can read what early infection can look like in our guide to hiv symptoms in men.
If your test is positive
A confirmed positive result is the start of treatment, not the end of a normal life. Antiretroviral therapy (ART) brings the virus down to undetectable levels — most people get there within about six months of starting — and a 20-year-old who begins treatment before their CD4 count drops too far now has a life expectancy approaching the general population's Lancet HIV. Undetectable equals untransmittable. Across the PARTNER studies, mixed-status couples logged over 125,000 condomless sex acts with zero linked transmissions while the HIV-positive partner stayed suppressed PARTNER study. Treatment protects your health and your partners' at once.
This page focuses on testing. The next steps — starting ART, what the medicines are, and what undetectable means in daily life — are covered on our HIV treatment page, which you should read next if you've just tested positive.
When to see a clinician
See someone right away in three situations: a possible exposure in the last 72 hours (for PEP), any reactive or positive HIV test (to confirm and start care), or acute flu-like symptoms after a known risk. A new HIV diagnosis is not an emergency in the ER sense, but starting ART early changes outcomes, so don't sit on it for weeks. If you're HIV-negative but keep facing exposures, that visit is also when to ask about PrEP, which cuts HIV risk from sex by about 99% when taken as prescribed CDC PrEP.