This Study Will Describe the Burden of DENgue Fever Virus (DENV) Illness Among Household Members Aged 6 Months to 50 Years of Selected Communities in Latin America and Southeast Asia

Study Overview
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Brief Summary
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The purpose of this study is to describe the burden of DENV illness among household members aged 6 months to 50 years of selected communities in Latin America and Southeast Asia.

Official Title
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A Cohort Study to Assess the Burden of Dengue Illness in Household Members From Selected Communities in Southeast Asia and Latin America

Conditions
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Dengue

Intervention / Treatment
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* Procedure: Blood sample collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Written and signed informed consent (and assent if the subject is below the legal age of consent) obtained from the subject/from subject's parent(s)/LAR(s). For a subject below the legal age of consent is, his/her signature will be obtained on the informed assent form, if applicable. A male or female between, and including 6 months and 50 years of age at the time of enrolment (Subjects become ineligible on their 51st birthday). Subject and/or the subject's parent(s)/LAR(s) who the investigator believes can comply with the requirements of the protocol (e.g., willingness to go to the hospital/healthcare centre for visit(s) in case of acute febrile illness, able to observe the signs of dengue and to understand how to take and report body temperature, etc). Subject who plans, at the time of enrolment, to remain at same residence/study area during the one or two year study period (as applicable). Household should be reachable by phone (residence phone or mobile phone). Note: Pregnant or lactating female or female planning to become pregnant can be recruited into the study. Exclusion Criteria: Child in care. Participation (current or planned) in another epidemiological study or in a clinical trial that would conflict with the current study, based on investigator's judgement. Terminal illness or severe mental incapacity.

Ages Eligible for Study
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Minimum Age: 6 Months
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Total Group<br>Subjects aged between 6 months and 50 years at the time of enrolment living in geographically-defined communities in Latin America and Southeast Asia. The study population comprised household members and should include between 30% and 50% of adults (aged 18 years or above) per site.The appropriate recruitment strategy was selected by each participating site. Two approaches might be considered: a school-based approach and a community-based approach without school involvement The expected period for recruiting the target sample size was approximately three months. | Procedure: Blood sample collection<br>* All participants will have an enrolment visit with collection of a blood sample and a termination contact/visit. Participants or their parents/guardians will be contacted weekly or every two weeks to monitor the occurrence of febrile episodes. Additional visits will be made if febrile episodes occur. In case of dengue suspicion, a blood sample will be collected.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence Percentage of Reverse Transcriptase Quantitative Polymerase Chain Reaction (RT-qPCR) Confirmed Symptomatic Dengue Infection During the Study Period by Study Site | Incidence percentage of RT-qPCR confirmed symptomatic dengue infection was expressed as percentage of subjects = (n [number of subjects with at least one event reported during the study period ]/N [number of subjects in the population]) X 100. The 95% Wald CI was calculated. Clustering effect was not retained because equal or less than 1. RT-qPCR confirmed symptomatic case = suspected dengue case (SDC) confirmed by RT-qPCR. See SDC definition in outcome 5. | From Day 0 to Month 24 (study end) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Subjects With DENV-type Specific Confirmed Symptomatic DENV Infection | Dengue Virus (DENV)-Type 1, 2 3 or 4 Ribonucleid acid would have been considered for this analysis but it was not performed due to the low number of cases reported. | From Day 0 to Month 24 (study end) | 
| Incidence Proportion of Virologically Confirmed Symptomatic Dengue Infection During the Study Period in Mexico | Incidence proportion of virologically confirmed symptomatic dengue infection was estimated from GEE logistic regression model taking the clustering effect into account. The 95% confidence interval was based on the robust variance estimate from the GEE model. Clusters were households for analysis by study site. Virologically confirmed symptomatic case = suspected dengue case (SDC) confirmed by RT-qPCR or non-structural protein 1 (NS1). See SDC definition in outcome 5. | From Day 0 to Month 24 (study end) | 
| Incidence Percentage of Virologically Confirmed Symptomatic Dengue Infection During the Study Period in the Philippines. | Incidence percentage of virologically confirmed symptomatic dengue infection was expressed as percentage of subjects = (n [number of subjects with at least one event reported during the study period]/N [number of subjects in the population]) X 100. The 95% Wald CI was calculated. Clustering effect was not retained because equal or less than 1. RT-qPCR confirmed symptomatic case = suspected dengue case (SDC) confirmed by RT-qPCR. See SDC definition in outcome 5. | From Day 0 to Month 24 (study end) | 
| Incidence Proportion of Probable Symptomatic Dengue Infection During the Study Period. | Incidence proportion of probable confirmed symptomatic dengue infection was estimated from GEE model with clustering effect. Clusters were households for analysis by study site and study sites for analysis on overall study sites. A probable confirmed dengue infection is an SDC with DENV RT-qPCR negative or not performed (late presenter), and DENV NS1 negative or undetermined (early or late presenter), and Anti-DENV Immunoglobulin type M (IgM) positive with a rapid immunochromatographic (ICT) assay or an Enzyme-linked Immunosorbent Assay (ELISA) assay, or Anti-DENV IgG positive (rapid ICT assay or 'capture ELISA' assay). SDC defined as acute febrile illness measured as greater or equal to 38.0°C or recent history of febrile illness (onset in the past 8 days) reported for at least 2 consecutive days (duration of approximately 36-48 hours) and < 7 days duration, which might be accompanied by other dengue symptoms or signs with no defined focus or obvious reason unrelated to dengue. | From Day 0 to Month 24 (study end) | 
| Proportion of Subjects With Dengue Virus Antibody IgG Positive Result (ELISA) at First Visit (Indicative of Past DENV Infection), by Study Site and Age Category. | The proportion of subjects with Dengue Virus antibody IgG positive result (ELISA) was estimated from GEE model with clustering effect. The 95% CI was based on the robust variance estimate from the GEE model. Clusters were households for analysis by study site. Ages categories were defined as follows: 6 months -<12 Months = from the 6 Months birthday up to and including the day before the 1st year birthday, and the next n-p Years categories = from the nth Year birthday up to and including the day before the (p+1)th Year birthday. Analysis was not summarized for confirmed and probable dengue cases, separately, as there were no probable cases reported in the study. | At Day 0 | 
| Percentage of Subjects With Dengue Virus Antibody IgG Positive Result (ELISA) at First Visit (Indicative of Past DENV Infection), by Study Site and Age Category. | The percentage of subjects with Dengue Virus antibody IgG positive result (ELISA) was expressed as percentage of subjects = (n [number of subjects with at least one event reported during the study period]/N [number of subjects in the population]) X 100. The 95% Wald CI was calculated. Clustering effect was not retained because equal or less than 1. Ages categories were defined as follows: 6 months -<12 Months = from the 6 Months birthday up to and including the day before the 1st year birthday, and the next n-p Years categories = from the nth Year birthday up to and including the day before the (p+1)th Year birthday. Analysis was not summarized for confirmed and probable dengue cases, separately as there were no probable cases reported in the study. | At Day 0 | 
| Number of Suspected Dengue Cases With Temperature and Any Symptom From First and Returned Visits | The following characteristics were summarized for each category of dengue cases (Virologically confirmed, probable, other SDC): Temperature at first visit: <37.5, ≥37.5, >38, >38.5, >39 °C and Clinical symptoms at onset, from first and returned visits. The results are presented for the virologically confirmed cases (VDC) and the other SDC (oSDC), no probable cases being reported in the study. | From Day 0 to Month 24 (study end) | 
| Number of Suspected Dengue Cases With Severity Criteria Characteristics | The clinical classification of the suspected dengue cases were distributed among following categories: Subject hospitalized during suspected dengue episode; OR At least 1 WHO 2009 warning signs: i.e. Abdominal pain or tenderness, Persistent vomiting, Clinical fluid accumulation, Mucosal bleed, Liver enlargement, Increase in HCT concurrent with rapid decrease in platelet count, Lethargy and restlessness; OR At least 1 WHO 2009 criteria for severe dengue: i.e. Severe Plasma Leakage leading to Shock, Fluid accumulation with respiratory distress, Severe Bleeding, Severe organ involvement; Liver: Aspartate transaminase or Alanine transferase ≥ 1000 International Unit/Liter, Central nervous system: impaired consciousness, Failure of heart and other organs; OR Most likely diagnosis for an episode of defined illnesses [investigator opinion]. The following characteristics were summarized for Virologically confirmed cases (VDC) and other SDC (oSDC), no probable cases being reported. | From Day 0 to Month 24 (study end) | 
| Number of Subjects With Serious Adverse Events (SAEs) Related to a Study Procedure | Serious adverse events (SAEs) assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization or result in disability/incapacity or is a congenital anomaly/birth defect in the offspring of a study subject.. | From Day 0 to Month 24 (study end) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dengue, Household, Southeast Asia, Latin America, Surveillance