Clinical trial NCT04945681: Evaluating the Effectiveness of a Pneumococcal Immunisation Campaign in a Camp for Internally Displaced People
Official title: Evaluating the Effectiveness of a Pneumococcal Immunisation Campaign in a Camp for Internally Displaced People: A Non-randomised, Quasi-experimental Phase IV Intervention Study
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: PHASE4
Conditions: Pneumococcal Infections
Keywords: Pneumococcal conjugate vaccine
Humanitarian
Crisis
Forced displacement
Mass vaccination
Quasi-experimental
Lead sponsor: London School of Hygiene and Tropical Medicine
Sponsor class: OTHER
Collaborators: name: Save the Children
name: Murdoch Childrens Research Institute
name: Ministry of Health Development, Somaliland
First posted: 2021-06-30
Enrollment: 2882
Sex: ALL
Minimum age (years): 6
Maximum age (years): 4
Standard ages: CHILD
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: Before vs. after quasi-experimental study. Entire study population of age-eligible children will be offered the intervention.
Primary purpose: PREVENTION

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.


Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

1. Known hypersensitivity to any component of any of the EPI vaccines, including diphtheria toxoid, in the child or any sibling
2. History of allergic disease or history of a serious reaction to any prior vaccination in the child or any sibling
3. History of anaphylactic shock, regardless of cause
4. 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

Primary outcomes:
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old
timeFrame: 6 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old
timeFrame: 12 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children below 24 months old
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Number and proportion of vaccination recipients who experience solicited local and systemic adverse events following immunisation (AEFI)
timeFrame: within 7 days of receipt of each vaccine dose
measure: Number and proportion of vaccination recipients who experience solicited or unsolicited severe adverse events (SAE) following vaccination
timeFrame: within 7 days of receipt of each vaccine dose
Secondary outcomes:
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older
timeFrame: 6 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older
timeFrame: 12 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of vaccine-type Streptococcus pneumoniae serotypes in children and adults 24 months old or older
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of non-vaccine-type Streptococcus pneumoniae serotypes in children and adults
timeFrame: 6 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of non-vaccine-type Streptococcus pneumoniae serotypes in children and adults
timeFrame: 12 months, relative to baseline (pre-vaccination)
measure: Nasopharyngeal carriage of one or more colonies of non-vaccine-type Streptococcus pneumoniae serotypes in children and adults
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Mean bacteriological density of vaccine- and non-vaccine-type Streptococcus pneumoniae infections, among children and adults with at least one infecting colony in the nasopharynx
timeFrame: 6 months, relative to baseline (pre-vaccination)
measure: Mean bacteriological density of vaccine- and non-vaccine-type Streptococcus pneumoniae infections, among children and adults with at least one infecting colony in the nasopharynx
timeFrame: 12 months, relative to baseline (pre-vaccination)
measure: Mean bacteriological density of vaccine- and non-vaccine-type Streptococcus pneumoniae infections, among children and adults with at least one infecting colony in the nasopharynx
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Incidence rate of hospitalisations due to acute lower respiratory infection (ALRI) among children aged below 2 years of age
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Rate of antibiotic prescription at outpatient care among children aged below 5 years of age
timeFrame: 24 months, relative to baseline (pre-vaccination)
measure: Proportion of the target population who receive the specified dosing regimen of pneumococcal conjugate vaccine during the vaccination campaign
timeFrame: Single time point - baseline (vaccination campaign)
Other outcomes:
Locations:
city: Hargeisa
country: Somalia
facility: Digaale internally displaced persons camp
state: Hargeisa, Somaliland
Study officials:
References:
citation: 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.