ELVIS Kids is a parallel, open label, randomised controlled trial (RCT) of Hypertonic Saline (HS) nose drops (~2.6% NaCl) vs. standard care in children <7 years of age with symptoms of an Upper Respiratory Tract Infection (URTI).

The study will run over ~30 months. Children are recruited prior to, or within 48 hours of developing URTI symptoms by advertising in areas such as local schools, nurseries, health centres and workplaces as well as social media. For the purposes of this study an URTI is defined as: at least two respiratory symptoms (nasal stuffiness, runny nose, cough, sore throat, or sneezing) OR one respiratory symptoms and at least one systemic symptom (lethargy, muscle pain, headache, pyrexia ≥38°C).

Willing parents/guardians, of children <7 years of age, will be directed by the study advertising to contact the research team at their local research site if they are interested in participating. Children will be randomised to either a Control arm of standard symptomatic care, or an Intervention arm of 3 drops each nostril of HS at least 4 times a day until 24 hours after asymptomatic or maximum of 28 days. All participants will be requested to obtain a mid-turbinate nasal swab prior to first nasal HS drops (repeated daily for 5 days), a daily symptom diary (CARIFS, a valid illness measure in the UK), and an end of illness questionnaire (healthcare use, adverse events, acceptability, infection in household contacts, parental time taken off usual activities). Parent/guardian of the children allocated to the intervention arm will be taught how to prepare the HS. Parent/guardian of children who are asymptomatic at recruitment are requested to inform CCRF when the child develops an URTI (within 48 hours) and follow the instructions already provided to them when given the go-ahead to start the trial. On day 28, parents/guardians will be contacted to determine if their child suffered from wheeze either during the illness or at any point until day 28. Participation in the study will end on day 28.

INCLUSION CRITERIA

1. Children between corrected gestational age of ≥40 weeks and <7 years of age

2. Children without URTI OR ≤48 hours of URTI* starting.

   • A URTI being defined as at least two respiratory symptoms (nasal congestion (i.e. stuffy nose), runny nose, cough, sore throat) OR one respiratory symptom + at least one systemic symptom (Low energy/tired, muscle aches/pains, headache, fever ≥38°C).

EXCLUSION CRITERIA

1. Children needing immediate medical attention
2. Children using saline drops/sprays at the time of randomisation
3. Children on immunosuppressive medication, regular oral/inhaled steroids, regular antibiotics (use of antibiotics is allowed as long as the child does not need regular antibiotics)
4. Children with a known chronic illness (e.g. cystic fibrosis, cardiac, renal, liver, lung, neurological conditions) apart from wheeze or asthma which are not exclusions if the child is otherwise well and not on regular steroids)
5. Children being followed up for developmental delay
6. Children receiving the nasal flu vaccine ≤14 days ago
7. Children taking part in another interventional trial
8. If parents/guardians indicating that they are unable to comply with the study protocol prior to randomisation
9. If parents/guardians are unable to understand written or spoken English
10. Children randomised to ELVIS KIDS on a previous episode of URTI
11. Children with a concurrently participating sibling

The team in the virology lab carrying out the analysis of the nasal swabs will be blinded to the allocation of the participant.