Study to Evaluate the Effectiveness of Rotarix™ Against Severe Gastroenteritis Among Hospitalized Children in Brazil

Study Overview
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Brief Summary
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The purpose of this study is to estimate the effectiveness of 2 doses of Rotarix™ vaccination in preventing rotavirus severe gastroenteritis among children hospitalized in Belem area, Brazil.

Detailed Description
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The study will be comprised of two parts: Case-control study and Rotavirus strain surveillance.

Official Title
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Case-control Study to Evaluate the Vaccine Effectiveness of Rotarix™ Against Rotavirus Severe Gastroenteritis (RV SGE) Among Hospitalized Children Born After 6 March 2006 and at Least 12 Weeks of Age, in Belem, Brazil

Conditions
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Rotavirus Gastroenteritis

Intervention / Treatment
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* Procedure: Stool sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: For cases: A male or female child born after 6 March 2006 and at least 12 weeks of age. Subject admitted to the study clinics/hospitals for severe gastroenteritis during the study period. Onset of severe gastroenteritis ≤ 14 days prior to admission. Laboratory confirmed rotavirus positive stool sample at hospital admission or during the first 48 hours of hospitalization. Written informed consent obtained from the parent or guardian of the subject. For controls: Admitted for non-gastroenteritis causes at the same clinic/hospital as the case. Living in the same neighbourhood as the case for at least three consecutive months without any symptoms of gastroenteritis or severe gastroenteritis on the day of interview of his/ her parents/ guardians. Being born within +- 2 weeks from the date of birth of the case. If the number required is not available, then the range would be extended to +- 4 weeks, and ultimately up to +- 6 weeks for hospital controls. For neighbourhood controls, the range may be extended to +- 8 weeks. Written informed consent obtained from the parent or guardian of the child. Exclusion Criteria: For cases: Subject has previously participated as case or control in this study. Onset of severe gastroenteritis > 48 hours after admission to the hospital (nosocomial infections). For controls: For hospital controls: Child who has symptoms of gastroenteritis during current hospitalization or on the day of interview of his/her parent or guardian or for neighbourhood controls: Child who has symptoms of gastroenteritis or severe gastroenteritis on the day of interview of his/her parent or guardian. Exclude children with the following vaccine preventable diseases: measles, mumps, rubella, diphtheria, pertussis, tetanus, tuberculosis, invasive Haemophilus influenzae type B (Hib) infections (meningitis, bacteraemia, septic arthritis, cellulitis, and epiglottitis) and hepatitis B. Child has participated in the past as a case or control in this study. Child living in the same house as the case

Ages Eligible for Study
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Minimum Age: 12 Weeks

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Gastroenteritis cohort<br>Children born after 6 March 2006, at least 12 weeks of age and hospitalized for rotavirus severe gastroenteritis | Procedure: Stool sampling<br>* Stool samples collected and checked for the presence of rotavirus<br>|
| Hospital control cohort<br>Children hospitalized for non gastroenteritis causes | |
| Neighbourhood control cohort<br>Children without any symptoms of gastroenteritis or severe gastroenteritis | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Risk of Enzyme Linked Immunosorbent Assay (ELISA) confirmed rotavirus severe gastroenteritis in children fully vaccinated with Rotarix™, compared to risk of ELISA confirmed rotavirus severe gastroenteritis in unvaccinated children |  | Average time frame: 12-24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Risk of ELISA confirmed rotavirus severe gastroenteritis in children vaccinated with at least one dose of Rotarix™, compared to risk of ELISA confirmed rotavirus severe gastroenteritis in unvaccinated children |  | Average time frame: 12-24 months | 
| Occurrence of severe gastroenteritis among children admitted to study clinics/hospitals for severe gastroenteritis |  | Average time frame: 12-24 months | 
| Occurrence of rotavirus serotypes among children |  | Average time frame: 36 months |