Please select the eligibility criteria that correspond to the clinical trial below.
Title: Prevention of Secondary Transmission of Human Influenza by Promoting Handwashing With Soap: The Bangladesh Interruption of Secondary Transmission of Influenza Study (BISTIS)
Brief Summary: The next influenza pandemic is expected to spread rapidly in resource-poor settings. Influenza viruses spread from human-to-human via large respiratory droplets. Transmission via large-particle respiratory droplets is believed to be mediated by close contact between infected and susceptible persons or contact with droplet-contaminated fomites. Close contact between infected and susceptible persons may consist of skin-to-skin contact (e.g., via hands) or inhalation of respiratory droplets (e.g., due to talking, coughing, or sneezing by the infected person). Airborne transmission, which is expected to result in transmission over long distances (\>1 meter) and which would be mediated by ventilation, is believed to be uncommon. Therefore, the greatest risk of transmission from personal contact comes from those people who are closest to an index case, such as contacts living in the same household. There are, to date, no published estimates of the secondary attack ratio of influenza among household contacts of index case-patients in low-income countries. Moreover, the investigators do not have data on the risk factors for secondary transmission of influenza from index case-patients to their household contacts. There is some data for the benefits of promoting handwashing with soap on the risk of all-cause acute respiratory illness among children \< 15 years old in a resource-poor setting in Pakistan. But, the investigators do not have evidence that promoting handwashing with soap will acutely reduce the risk of secondary transmission. Therefore, the investigators propose to conduct a study in rural Bangladesh to assess the following:

* The secondary attack ratio of influenza among household contacts of an index case-patient with influenza
* The risk factors for secondary transmission of influenza from an index case-patient to household contacts
* The impact of promoting handwashing with soap on the risk of secondary transmission of influenza from an index case-patient to household contacts
* The impact of handwashing promotion on handwashing behavior six months after intervention
* The impact of handwashing promotion on the prevalence of respiratory infections, diarrhea and influenza


Options:
A: Inclusion Criteria:

* Persons ≥ 5 years old: Influenza-like illness (ILI), defined as history of fever and either cough or sore throat with fever onset within the previous 24 hours
* Persons \< 5 years old: any child with acute fever with onset within the previous 24 hours
* Return to home within 24 hours of presentation to Upazilla Health Complex, Jahurul Islam Medical College Hospital or the local pharmacies; i.e., the index case cannot be admitted for treatment. If admitted, the patient would not be eligible.
* No fever in any bari resident during the 7 days preceding the patient's presentation to hospital (see definition below)
* At least two persons (in addition to the index case-patient) who intend to reside in the bari during the subsequent 20 days
* Residence within 30 minutes travel time (one-way) from the Upazilla Health Complex or Jahurul Islam Medical College Hospital or the local pharmacy.
B: Inclusion Criteria:

* influenza like illness symptoms
* positive rapid test for influenza
* inclusion within 48h of symptom onset
* inclusion of at least 3 members of a household (including index case)

Exclusion Criteria:

* severe illness
* other cases of similar symptoms within 14 days before onset of symptoms in index patient
* severe asthma or COPD
* pregnancy of index
C: Inclusion Criteria:

* Clinical site leadership has agreed to have one or more staff participate in the trial
* Subject meets the definition of "healthcare personnel"
* Subject able to read and sign informed consent
* Subject agrees to all requirements of the protocol, including fit testing and diary keeping
* Subject's age is 18 or greater
* Subject passes fit testing for one of the study supplied respirator models and agrees to use that model for the entire intervention period of the study (if in respirator arm).

Exclusion Criteria:

* Subject self-identified as having severe heart, lung, neurological or other systemic disease that one or more Investigator believes could preclude safe participation
* Known to not tolerate wearing respiratory protective equipment for any period
* Facial hair, or other issue such as facial adornments, precluding respirator OSHA-compliant fit testing or proper mask fit during the study period
* Advised by Occupational Health (or other qualified clinician) to not wear the same or similar respirator or medical mask models used in this study
* In the opinion of the Investigator, may not be able to reasonably participate in the trial for any reason
* Self-identified as in, or will be in the third trimester of pregnancy, during the study period.
* Subject rotating in 2 different ResPECT study clinic sites /clusters during the 12-week study period.
* Subject works less than 75% of the intervention period in that clinic.
* Subject is a previous participant of the ResPECT Study, but does not consent for data from previous flu season(s) to be linked.
D: Inclusion Criteria:

* Current or part-time student at McMaster University
* 17 year of age or older
* Currently living:

  i. In residence or, ii. Off-campus with at least one student housemate
* Willing and able to sign an informed consent

Exclusion Criteria:

* Students who do not meet the inclusion criteria
* Currently living at home with parents
* History or diagnosis of hypercalcemia
* Diagnosis of parathyroid disorder (hyper or hypo)
* Diagnosis of chronic kidney disease
* Use of anticonvulsants
* Malabsorption syndromes
* Diagnosis of sarcoidosis
* Currently pregnant or planning a pregnancy
* Inability to swallow capsules

Answer: A