Intervention
ARI, Stock
ACUTE RESPIRATORY INFECTION
Eligible mother–infant pairs are randomised with equal probability to receive either weekly vitamin D (coconut oil plus cholecalciferol) or placebo (coconut oil only).Both liquid active and placebo study medicines are manufactured and supplied by Ddrops, Ontario, Canada. Ddrops recommends storage in an upright position between 5°C and 30°C though the product has passed long term stability tests at 40°C. Stock medicine bottles and prefilled syringe doses (capped and placed in a labelled envelope) were both stored in the Menzies School of Health Research (MSHR) pharmacy at ambient temperature (approximately 21°C) prior to dosing. Mothers who received doses for self-administration were instructed to keep them in a secure, unrefrigerated location inside their house.The maternal vitamin D dose is 14 000 IU/week (equivalent to 2000 IU/day); the infant dose is 4200 IU/week (equivalent to 600 IU/day). Mothers vitamin D or placebo commences at enrolment (28Participant timeline*Window for visit 2 or birth visit: 0–14 days; visit 3 or 4-month visit: 3.5–6 months; visit 4 or 12-month visit: 11–18 months.†Hospital or primary healthcare presentation.ARI, any acute respiratory infection; CBMC, cord blood mononuclear cells; 25OHD, 25-hydroxy-vitamin D.Study medicines are self-administered orally via prefilled syringes (mother: 0.4 mL; infant 0.2 mL). though study staff assist as requested. Doses are ideally taken 7 days apart. A dose delayed more than 11 days is considered a missed dose and the next dose taken as scheduled. There is no catch up for missed doses and >3 consecutive missed doses is considered a protocol deviation.