Comparison of Influenza Test Types: Differences between Rapid Antigen, PCR, and Immunochromatography, and Usage in 2025
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When influenza is suspected, medical institutions primarily use the “Rapid Antigen Test,” but there are also more highly accurate methods like the “PCR Test” and the newer “Immunochromatography Method.” The type of test used significantly affects the time required to get results and, most importantly, the “Accuracy (Sensitivity).”
Summary of Influenza Test Types (As of 2025 in Japan)
Type
Time Required
Sensitivity (Accuracy)
Primary Usage Scenario
Approx. Cost (30% Co-pay)
Notes
1. Rapid Antigen Test(Most Common)
10–15 minutes
Type A: 80–95%
Type B: 60–85%
Almost all clinics and hospitals
¥600–¥1,200
2. Immunochromatography(Newest Rapid Test)
5–10 minutes
Type A: Approx. 93%
Type B: Approx. 82%
Some large hospitals and fever clinics
¥800–¥1,500
3. PCR Test (Genetic Test)
1–6 hours (Same day to next day)
Nearly 100%
Severe patients, inpatients, elderly care facilities, school/workplace outbreaks
¥1,500–¥3,000
Requires nasopharyngeal swab. False negatives are nearly zero.
4. Real-Time PCR(Highest Accuracy)
40 minutes – 2 hours
99.9%+
Large hospitals, university hospitals, designated infectious disease facilities
¥2,000–¥4,000
Can also test for COVID simultaneously.
5. LAMP Method (Isothermal)
30–60 minutes
Approx. 98%
Some fever clinics and emergency night clinics
¥1,800
Slightly faster than standard PCR.
6. Antibody Test (Blood Test)
Same day to several days
Meaningless
Rarely used
–
Only shows if you had it in the past, so not used for current diagnosis.
Actual Usage in Clinical Settings (As of 2025)
Situation
Test Used
Went to a regular internal medicine/pediatric clinic with a fever
→ 99% is the Rapid Antigen Test
Tested negative but symptoms strongly suggest flu
→ Retest the next day (Rapid) or switch to PCR
High-risk patients (elderly, chronic illness, severe risk)
→ Often requested to use PCR from the start
Multiple positive cases at a school or company
→ The public health center may instruct PCR for everyone
Nighttime emergency clinics / Fever clinics
→ Immunochromatography (New rapid) or PCR
In Short (2025)
Most people will undergo the “15-minute nasal swab rapid test” almost 100% of the time.
“Those who absolutely need an accurate result” or “high-risk individuals” will get PCR.
If a rapid test is negative but symptoms are strong, doctors will half-believe the symptoms and prescribe medication.
At-Home Testing Kit Ranking (Combined COVID-19 and Influenza)
Here is the English translation of the ranking table for at-home diagnostic kits that test for both COVID-19 and Influenza A/B:
