By InvitationNot Applicable

Effect of Surgical Masks in Preventing Acute Respiratory Infections

Japan2,000 participantsStarted 2026-07

Plain-language summary

The goal of this clinical trial is to evaluate the efficacy of surgical masks in preventing acute respiratory tract infections. The main question it aims to answer is: \- Does wearing a mask prevent you from getting acute respiratory tract infections, including influenza and COVID-19 Researchers will compare a surgical mask to no intervention to see if wearing a mask works to prevent acute respiratory infection. Participants will: * Wear or not wear a surgical mask every day * Answer a questionnaire every 2 weeks on symptoms, testing status, and behaviors This trial does not assess if wearing a mask prevents transmission of pathogens when you are already sick. Also, the trial does not assess whether universal masking (where everyone wears masks) works.

Who can participate

Age range

20 Years – 49 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Those who originally do not wear a mask during the influenza season * Those aged 20 years or older and under 50 years at the time of providing informed consent * If assigned to the mask group, those who can agree to wear a mask when going outdoors for 3 to 4 months during the influenza season (excluding times such as when eating) * In the case of the non-mask group, those who can agree, in principle, not to wear a mask for 3 to 4 months during the influenza season * Those who can agree to undergo testing for both influenza and COVID-19 on the day of onset or the following day if symptoms suggestive of influenza, COVID-19, or a common cold (such as fever or respiratory symptoms) develop, and to visit a medical institution at their own expense for medical fees * Those who usually go out 3 or more days a week * Those who have obtained the agreement of cohabiting family members regarding participation * Those who, after receiving a thorough explanation regarding participation in this study and with full understanding, have provided written informed consent based on their own free will Exclusion Criteria: * Those who originally wear a mask during the influenza season and intend to continue doing so in the future * Those who are engaged in healthcare, food manufacturing, etc., and wear a mask during regular work * Those who are pregnant * Those with underlying medical conditions such as chronic liver disease, cancer, or cardiovascular disease * Those who ha…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Laboratory-confirmed influenza

Timeframe: From start of influenza season to the end of data collection at 14 weeks

Trial details

NCT IDNCT07739446

SponsorChiba University

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2027-03

View on ClinicalTrials.gov More Acute Respiratory Infections (ARIs) trials