Post-marketing study to assess the risk of intussusception (IS) after immunization with Rotarix PCV-free liquid vaccine in infants less than 1 year old in Latin America

Inclusion criteria for enrolment of IS cases: All IS cases must satisfy ALL the following criteria at study entry:

• A male or female participants aged at least 6 weeks old and less than 1 year at the time of diagnosis of definite IS (participants are ineligible before 6 weeks of age and as of their first birthday).
• Participant hospitalized or visiting the ER of the participating hospitals during the study period for definite IS.
• Participant whose parent(s)/Legally Acceptable Representative(s) (LAR[s]), in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., agree to provide vaccination status during contact follow-up if not available at enrolment visit).
• Participant whose parent(s)/LAR(s), provide written informed consent (according to applicable local regulations). Inclusion criteria for enrolment of controls: All control participants must satisfy ALL the following criteria at study entry:
• A male or female participant aged at least 6 weeks old and less than 1 year at the time of hospitalization or visit to the hospital outpatient clinic or ER (participants are ineligible before 6 weeks of age and as of their first birthday).
• Participant hospitalized or visiting the hospital outpatient clinic or the ER of the participating hospitals during the study period with no gastro-intestinal symptoms (including gastro-enteritis and IS).
• Participant whose parent(s)/LAR(s), in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., agree to provide vaccination status during contact follow-up if not available at enrolment visit).
• Participant whose parent(s)/LAR(s), provide written informed consent (according to applicable local regulations).

Exclusion criteria for enrolment of IS cases: The following criteria should be checked at the time of study entry. If ANY exclusion criterion applies, the IS case must not be included in the study:

• Participant has previously participated as a case or a control in this study, either in the same hospital or in another participating hospital.
• Participant is enrolled in another clinical trial. Exclusion criteria for enrolment of controls: The following criteria should be checked at the time of study entry. If ANY exclusion criterion applies, the control must not be included in the study:
• Participant has previously participated as a case or a control in this study, either in the same hospital or in another participating hospital.
• Participant is enrolled in another clinical trial.
• Participant has gastro-intestinal symptoms (including gastro-enteritis and IS) during current hospitalization/visit to the hospital outpatient clinic or ER, at the time of enrolment visit.