Evaluating the Effectiveness of a Pneumococcal Immunisation Campaign in a Camp for Internally Displaced People

NCT04945681 | Active Not Recruiting Phase 4

• 1 other identifier: OPP1211787
• Study Type: interventional
• Target: 2,882
• Locations: 1 country
• Sites: 1

Brief Summary

Pneumococcal conjugate vaccine (PCV) is used routinely worldwide as part of infant immunisations to prevent acquisition of S. pneumoniae, the aetiologic agent responsible for a large proportion of early childhood pneumonia and invasive disease. However, PCV has seen minimal uptake in populations affected by forced displacement and humanitarian crises, where the burden of pneumococcal disease is plausibly elevated. This study seeks to generate evidence on appropriate vaccination strategies for crisis-affected populations. The investigators plan to exhaustively vaccinate children aged between six months and four years in a camp for displaced persons outside Hargeisa, the capital of Somaliland. The study will deliver PCV in a campaign modality, so as to achieve both short- and long-term herd immunity effects that, the investigators hypothesise, will reduce population-wide nasopharyngeal S. pneumoniae transmission and thereby protect young children from pneumococcal disease. The study will adopt a quasi-experimental design, with baseline and post-intervention surveys to evaluate changes in pneumococcal carriage, complemented by safety assessment in children aged over 2 years, who fall outside of the WHO prequalification age range for the vaccine that will be used in this study (i.e. PNEUMOSIL) and for whom PCV safety data are scarce. In addition, we the study will also collect longitudinal data on incidence of pneumonia and antibiotic prescriptions in the camp.

Conditions

Pneumococcal Infections

Keywords

Pneumococcal conjugate vaccine; Humanitarian; Crisis; Forced displacement; Mass vaccination; Quasi-experimental

Outcome Measures

Primary Outcomes (5)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old

  The outcome is determined at the individual level, through polymerase chain reaction (PCR) microarray analysis of nasal swab samples collected during a cross-sectional, population-representative sample survey of camp residents. The analysis will be stratified by age group (0-11 months, 12-23 months). Vaccine-type serotypes are defined as those that the Pneumosil vaccine (Serum Institute, India) is designed to provide immunity for, and include serotypes serotypes 1, 5, 6A, 6B, 7F, 9V, 14, 19A, 19F and 23F.

  6 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old

  The outcome is determined at the individual level, through PCR microarray analysis of nasal swab samples collected during a cross-sectional, population-representative sample survey of camp residents. The analysis will be stratified by age group (0-11 months, 12-23 months). Vaccine-type serotypes are defined as those that the Pneumosil vaccine (Serum Institute, India) is designed to provide immunity for, and include serotypes serotypes 1, 5, 6A, 6B, 7F, 9V, 14, 19A, 19F and 23F.

  12 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old

  The outcome is determined at the individual level, through PCR microarray analysis of nasal swab samples collected during a cross-sectional, population-representative sample survey of camp residents. The analysis will be stratified by age group (0-11 months, 12-23 months). Vaccine-type serotypes are defined as those that the Pneumosil vaccine (Serum Institute, India) is designed to provide immunity for, and include serotypes serotypes 1, 5, 6A, 6B, 7F, 9V, 14, 19A, 19F and 23F.

  24 months, relative to baseline (pre-vaccination)

• Number and proportion of vaccination recipients who experience solicited local and systemic adverse events following immunisation (AEFI)

  The outcome is determined at the individual level. 'Solicited' indicates that adverse events are identified by study staff using a pre-defined checklist of signs and symptoms and proactive monitoring or follow-up of vaccine recipients. AEFI will be coded using the Medical Dictionary for Regulatory Activities (MedDRA) (version 24.0 or later). Outcome ascertainment will occur through (i) in-person monitoring of vaccine recipients for 30 minutes after vaccine administration, and (ii) exhaustive follow-up of all vaccine recipients 7 days after vaccination, with administration of a structured questionnaire to their parents or caregivers. All AEFI will be graded using a severity scale (0 - none; 1 - mild; 2 - moderate; 3- severe; 4 - very severe; 5 - fatal), and analysis will be stratified by severity and age group (6 weeks to 11 months old, 12 to 23 months old, 24 to 59 months old).

  within 7 days of receipt of each vaccine dose

• Number and proportion of vaccination recipients who experience solicited or unsolicited severe adverse events (SAE) following vaccination

  The outcome is determined at the individual level. SAE are defined as any AEFI with severity \>= 3. Outcome ascertainment will occur through (i) in-person monitoring of vaccine recipients for 30 min after vaccine administration, (ii) exhaustive follow-up of all vaccine recipients 7 days after vaccination, with administration of a structured questionnaire to their parents or caregivers; (iii) availability of a 24/7 phone number which caregivers of vaccine recipients will be encouraged to contact; (iv) visits to the camp's single primary healthcare facility, during each day on which vaccination takes place, to identify any children presenting for care with a SAE; and (v) availability of a 24/7 phone number which clinicians at the primary healthcare facility will be encouraged to contact. Each SAE will be followed up until resolution. Relatedness of each SAE to vaccine receipt will be classified as 'unrelated', 'unlikely', 'possible', 'probable', 'definite' and 'not assessable'.

  within 7 days of receipt of each vaccine dose

Secondary Outcomes (12)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older

  6 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older

  12 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older

  24 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of non-vaccine-type Streptococcus pneumoniae serotypes in children and adults

  6 months, relative to baseline (pre-vaccination)

• Nasopharyngeal carriage of one or more colonies of non-vaccine-type Streptococcus pneumoniae serotypes in children and adults

  12 months, relative to baseline (pre-vaccination)

Study Arms (1)

Mass vaccination

EXPERIMENTAL

Mass vaccination of children aged 6 weeks to 4 years old with pneumococcal conjugate vaccine (PNEUMOSIL). Children 6 weeks to 11 months old receive two doses, spaced 4 weeks apart. All other children receive a single dose. Vaccination is simultaneous, as per a campaign delivery strategy.

Biological: Pneumococcal conjugate vaccine

Interventions

Pneumococcal conjugate vaccine BIOLOGICAL

Mass campaign offering simultaneous pneumococcal conjugate vaccination to all children aged below 5 years of age living in Digaale camp, Somaliland. Children aged below 12 months receive 2 doses of vaccine, spaced 4 weeks apart. All other children receive one dose.

Mass vaccination

Eligibility Criteria

• Age: 6 Weeks - 4 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Resident in Digaale camp
• Voluntary written/thumb-printed informed consent has been provided by a parent or caregiver
• Subject's parent/caregiver must be able to comprehend and comply with study requirements and procedures
• Subject's parents/caregivers must have a readily identifiable place of residence in the study area

You may not qualify if:

• Known hypersensitivity to any component of any of the EPI vaccines, including diphtheria toxoid, in the child or any sibling
• History of allergic disease or history of a serious reaction to any prior vaccination in the child or any sibling
• History of anaphylactic shock, regardless of cause
• History of long-term treatment (defined as 14 or more consecutive days) with immunosuppressants or other immune modifying drugs, including glucocorticoids, but excluding topical and inhaled glucocorticoids

Sponsors & Collaborators

• London School of Hygiene and Tropical Medicine: lead
• Save the Children: collaborator
• Murdoch Childrens Research Institute: collaborator
• Ministry of Health Development, Somaliland: collaborator

Study Sites (1)

Digaale internally displaced persons camp

Hargeisa, Hargeisa, Somaliland, Somalia

Location

Related Publications (2)

• van Zandvoort K, Hassan AI, Bobe MO, Pell CL, Ahmed MS, Ortika BD, Ibrahim S, Abdi MI, Karim MA, Eggo RM, Ali SY, Hinds J, Soleman SM, Cummings R, McGowan CR, Mulholland EK, Hergeye MA, Satzke C, Checchi F, Flasche S. Pre-vaccination carriage prevalence of Streptococcus pneumoniae serotypes among internally displaced people in Somaliland: a cross-sectional study. Pneumonia (Nathan). 2024 Dec 5;16(1):25. doi: 10.1186/s41479-024-00148-6.

  PMID: 39633426 BACKGROUND

• McGowan CR, van Zandvoort K, Ibrahim SA, Hassan AI, Ahmed AM, Magan MA, Muhumed MH, Mohamed MS, Cummings R, Ali SY, Mohamed MA, Saed MA, Karim MA, Hergeye MA, Flasche S, Checchi F. Safety and coverage of Pneumosil pneumococcal polysaccharide conjugate vaccine (10-valent PCV) in a camp for internally displaced persons in Somaliland. Vaccine. 2026 Jan 1;69:127991. doi: 10.1016/j.vaccine.2025.127991. Epub 2025 Nov 19.

  PMID: 41265006 DERIVED

MeSH Terms

Conditions

Pneumococcal Infections

Interventions

Pneumococcal Vaccines

Condition Hierarchy (Ancestors)

Streptococcal Infections; Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections

Intervention Hierarchy (Ancestors)

Streptococcal Vaccines; Bacterial Vaccines; Vaccines; Biological Products; Complex Mixtures

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Before vs. after quasi-experimental study. Entire study population of age-eligible children will be offered the intervention.

Study Record Dates

• First Submitted: June 14, 2021
• First Posted: June 30, 2021
• Study Start: November 27, 2022
• Primary Completion: January 18, 2025
• Study Completion: February 28, 2026
• Last Updated: June 4, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: ANALYTIC CODE
• Time Frame: June 2026 - May 2036
• Access Criteria: Researchers wishing to apply for data should complete and submit a data application form, outlining the research purpose for which they wish to use the data, a list of variables that they wish to access, and information on how they fulfil the access conditions. If the application fulfils the eligibility criteria, the applicant will be provided with a Data Transfer Agreement that must be signed by their host organisation.

Locations

SO (1)