NCT07640581

Brief Summary

This is a prospective, observational, multicenter study employing continuous, convenience sampling, stratified by study site and by fortnightly interval, enrolling until the target sample sizes are achieved over the first epidemiological season (2026) and the second epidemiological season (2027). The study population includes children aged 0 to 24 months presenting to the outpatient or inpatient facilities of the study sites with signs and symptoms of acute respiratory infection (ARI). In Vietnam there is no single guideline for diagnosing ARI, but rather there are guidelines specific to clinical conditions such as pharyngitis, rhinitis, tonsilitis, or pneumonia. This study will use an operational definition where ARI is defined as the presence of one or more of the following clinical features: cough, rhinorrhea, sore throat, dyspnea, and / or fever. RSV testing using nasopharyngeal (NP) swabs will be collected from all eligible children with consent to participate in the study; if a NP swab is not feasible, a mid-turbinate nasal swab will be used. Specimens will be transported to a central laboratory for real-time, reverse transcription-polymerase chain reaction (RT-PCR) testing. Furthermore, the stored viral transport media from all the RSV-positive samples will be used for whole genome sequencing (WGS) to determine the subgroup (A or B) of the circulating RSV strains and to analyze the genotype. The parent or legally acceptable representative (LAR) of pediatric patients will provide information regarding the patient's demography, such as the family's socioeconomic status and household environment (e.g., exposure to tobacco smoke, overcrowding). The children's immunization history and their mothers' immunization history (i.e., vaccines such as influenza and Tdap received during the pregnancy as part of a maternal immunization program) will be established, which is not to estimate vaccine effectiveness but to document the level of vaccine uptake in these populations during the study. Children with maternal RSV vaccination will be excluded. Crucially, the parent or LAR also will report on the child's complete medical history, including perinatal / pregnancy history, presence of congenital anomaly, previous history of illness, and detailed history and clinical course of the current illness episode. Maternal hypertension and history of immunological factors will not be explored. Data on the medical treatment will be abstracted from the patients' medical records. One month after the outpatient clinic visit or hospital discharge, the parent or LAR will be contacted via mobile phone to ascertain the children's current health status and to collect information on the family's direct costs due to the illness.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
2,000

participants targeted

Target at P75+ for all trials

Timeline
24mo left

Started Jun 2026

Typical duration for all trials

Geographic Reach
1 country

3 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress7%
Jun 2026Aug 2028

First Submitted

Initial submission to the registry

May 21, 2026

Completed
14 days until next milestone

Study Start

First participant enrolled

June 4, 2026

Completed
6 days until next milestone

First Posted

Study publicly available on registry

June 10, 2026

Completed
2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 4, 2028

Expected
2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2028

Last Updated

June 10, 2026

Status Verified

June 1, 2026

Enrollment Period

2 years

First QC Date

May 21, 2026

Last Update Submit

June 6, 2026

Conditions

Outcome Measures

Primary Outcomes (3)

  • Proportion of ARI that is RSV positive

    Frequencies, percentages of RSV positivity

    Through study completion, an average of 2 years

  • The seasonal patterns of RSV infection

    Time-series analysis of infection RSV will be performed to assess seasonal trends

    Through study completion, an average of 2 years

  • Clinical burden of infection RSV

    Frequencies, percentages of hospitalization among infection RSV

    Through study completion, an average of 2 years

Secondary Outcomes (2)

  • Whole-genome sequencing results

    Through study completion, an average of 2 years

  • Direct medical costs

    Through study completion, an average of 2 years

Eligibility Criteria

Age0 Months - 24 Months
Sexall
Healthy VolunteersNo
Age GroupsChild (0-17)
Sampling MethodNon-Probability Sample
Study Population

The study population includes children aged 0 to 24 months presenting to the outpatient or inpatient facilities of the study sites with symptoms of acute respiratory infection (ARI).

You may qualify if:

  • Children aged 0 to \<24 months (i.e., less than two years old).
  • Children presenting with a diagnosis of acute respiratory infection (ARI), defined as an illness with one or more of the following symptoms: cough, rhinorrhea, sore throat, dyspnea (including wheezing, tachypnea, or apnea/increased work of breathing), sepsis (for infants aged \<6 months), and/or fever.
  • Children residing in the lowest administrative division (Phường / Xã) in Vietnam that is designated for the specific study site (outpatient clinic or community hospital). As patients live in the same administrative district as the healthcare facility, this will facilitate follow-up and ensure that the study results are representative of the range of severity of ARI presenting to each specific study site.
  • Parent or LAR provides written informed consent for their child's participation.

You may not qualify if:

  • Children whose mothers received a maternal RSV vaccine during pregnancy or who have themselves received RSV-specific monoclonal antibodies (mAbs).
  • Children with a known non-respiratory cause for hospitalization.
  • Children with respiratory symptoms lasting over 14 days.
  • Children hospitalized elsewhere within the preceding 4 days, excluding admission to the Emergency Department.
  • Children already enrolled in another RSV study within the preceding 3 months.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (3)

Ba Ria General Hospital

Ho Chi Minh City, Ho Chi Minh, 700000, Vietnam

NOT YET RECRUITING

Di An Medical Center

Ho Chi Minh City, Ho Chi Minh, 700000, Vietnam

RECRUITING

Le Van Thinh Hospital

Ho Chi Minh City, Ho Chi Minh, 700000, Vietnam

NOT YET RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

Following enrollment, a nasopharyngeal swab will be collected from the participant by a trained research nurse as soon as possible, but within 24 hours of ICF signing. The sample will be collected using a sterile nylon flocked swab and immediately placed into a tube containing 3 ml of viral transport medium (VTM).

Central Study Contacts

Dung Van Do, MD, PhD

CONTACT

Study Design

Study Type
observational
Observational Model
OTHER
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 21, 2026

First Posted

June 10, 2026

Study Start

June 4, 2026

Primary Completion (Estimated)

June 4, 2028

Study Completion (Estimated)

August 1, 2028

Last Updated

June 10, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will not share

Locations