An interventional study of Surgical masks in Acute Respiratory Infections (ARIs), Influenza and COVID - 19, sponsored by Chiba University. Enrolling by invitation at 1 site in Japan. Open to participants aged 20 Years to 49 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by Chiba University · Not applicable, Interventional, and Prevention
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:
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.
2,356 studies on the registry are indexed under Influenza, Human; 184 are open to participants now.
This study's planned enrollment of 2,400 is above the median of 227 across 1,957 interventional studies indexed under Influenza, Human.
Browse Influenza, Human studies →Chiba University is the lead sponsor of 17 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in this group are provided with masks and asked to wear them every day
Behavioral: Surgical masks
Participants in this group are not provided with masks and are asked not to wear them every day
Participants in this group are provided with masks and asked to wear them every day
Acute respiratory infection
Syndromic outcome based on self-report
Time frame: From start of influenza season to the end of data collection at 14 weeks
Laboratory-confirmed influenza
Laboratory-confirmed influenza based on testing done at healthcare facilities
Time frame: From start of influenza season to the end of data collection at 14 weeks
Laboratory-confirmed COVID-19
Laboratory-confirmed COVID-19 based on testing done at healthcare facilities
Time frame: From start of influenza season to the end of data collection at 14 weeks
Laboratory-confirmed influenza or COVID-19
Laboratory-confirmed influenza or COVID-19 based on testing done at healthcare facilities
Time frame: From start of influenza season to the end of data collection at 14 weeks
Antibody response in sebum specimens
Antibody response in sebum specimens collected for laboratory-confirmed influenza cases among participants
Time frame: From start of influenza season to the end of data collection at 14 weeks
Plan to share: No — The datasets generated and/or analyzed during the current study are not publicly available due to privacy regulations protecting participant confidentiality and identifiable data.
No publications or documents are linked to this record.
Started Jul 2026 (actual). Primary completion is estimated for Mar 2027, 8 months after the start.
Of 146 non-industry interventional studies with no phase under Influenza, Human, half reached primary completion within 7 months of starting (the median), counting those still running; a quarter within 3 and three quarters within 18. This study's planned 8 months is above that.
Counting every sponsor, half of 166 studies reached it within 6 months; a quarter within 3 and three quarters within 16.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
No contact was published for this record. The registry link below has the sponsor’s details.
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Chiba University