Rapid Antigen Test: Fast COVID-19 Screening at Home and Clinics

Rapid antigen tests give quick results for respiratory viruses, most commonly SARS‑CoV‑2. They detect viral proteins, not genetic material, so they deliver answers fast—usually within 15–30 minutes. That speed makes them useful for screening before events, travel, work, or when symptoms start.

How to use a rapid antigen test properly

Follow the kit instructions step by step. Wash or sanitize hands before and after the test. Collect the sample exactly as shown—nasal swabs are common and less deep than PCR swabs. Rotate and hold the swab as directed, place it into the extraction solution, then apply drops to the test strip. Start the timer the moment you add the sample. Read the result only within the time window specified; reading too early or too late can give wrong answers.

Reading and acting on results

A clear positive line means the test detected viral proteins. Treat a positive as infectious: isolate, notify close contacts, and follow local guidance on reporting. If you have symptoms but the antigen test is negative, consider retesting after 24–48 hours or get a PCR test. If you need confirmation for travel or medical reasons, PCR is the gold standard.

Sensitivity varies. When viral load is high, antigen tests often catch infections reliably. Early in symptoms or with high contagiousness they work best. But they miss some cases, especially in people without symptoms or late after infection. Specificity is generally high, so a positive result usually means you are infected, but false positives can still happen.

Common mistakes and tips: Skipping swab rotation, using an expired kit, or adding the wrong number of drops are frequent errors. Store kits at the temperature range on the box and avoid direct sunlight. If you get an unclear or invalid result, repeat the test with a new kit. For children, slow gentle swabbing is best; for older adults, get help if dexterity is an issue.

When to choose antigen vs PCR: Pick antigen tests for fast screening, frequent testing, or when you need immediate decisions. Choose PCR when you need higher sensitivity, official proof for travel or hospital clearance, or when timing is beyond the window where antigens perform well.

Limitations and safety: Antigen tests won't tell you how contagious you are beyond indicating presence of viral proteins. They can't replace clinical judgment. If you have severe symptoms—trouble breathing, chest pain, fainting—seek urgent medical care regardless of test results.

Where to get tests: Pharmacies, clinics, community testing sites, and reputable online sellers stock antigen kits. Buy tests from trusted vendors and check that instructions are in your language. Keep a few kits at home during high-risk seasons.

Track your results in a simple log—date, time, brand, and result—and include symptom notes. This helps you notice patterns and share clear information with your clinician if needed. If a workplace or school requires proof, follow their reporting rules. If unsure, call your doctor or local health line for next steps. Store tests safely, away from children and pets.