Acute Respiratory Illness (ARI), Infant Outcomes, Lower Respiratory Tract Disease, Maternal Immunization, Respiratory Syncytial Virus (RSV)
Conditions
Keywords
respiratory syncytial virus, respiratory syncytial virus bivalent prefusion F vaccine, acute respiratory illness, lower respiratory tract disease, Maternal immunization, Tarsila study
Brief summary
The overall objective of Tarsila Study is to estimate the real-world vaccine effectiveness of maternal RSVpreF immunization during pregnancy in Brazil against medically attended (inpatient and outpatient) respiratory syncytial virus-associated acute respiratory illness in infants. To achieve this, two multicenter, prospective, test-negative case-control studies will be conducted among infants with ARI: the TARSILA Inpatient Study, evaluating hospitalized infants and the TARSILA Outpatient Study, evaluating infants managed in outpatient settings.
Detailed description
Tarsila comprises two multicenter, prospective, case-control studies using a test-negative design in Southern Brazil (states of Rio Grande do Sul, Santa Catarina, and Paraná). The Tarsila Inpatient study will enroll infants hospitalized due to acute respiratory illness and will be conducted at referral hospitals. The Tarsila Outpatient study will enroll infants with acute respiratory illness managed in outpatient settings and will be conducted at outpatient healthcare facilities. Both studies are aligned with the nationwide introduction of maternal RSVpreF vaccination in December 2025, with enrollment occurring from April, 2026 to September, 2028. In both studies, the same clinical case definition will be applied to cases and controls. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) for RSV will be prospectively performed to classify case infants (RT-qPCR positive for RSV) and control infants (RT-qPCR negative for RSV). Maternal RSVpreF vaccination status and potential confounders will be assessed through structured interviews and review of medical records.
Interventions
BIOLOGICALrespiratory syncytial virus bivalent prefusion F vaccine
For both studies, the primary exposure is maternal receipt of respiratory syncytial virus bivalent prefusion F vaccination during pregnancy in accordance with the Brazilian National Immunization Program recommendation (24⁺⁰/₇ to 36⁺⁶/₇ weeks' gestation) with the receipt of the vaccine 14 days or more before delivery.
Sponsors
Inova Medical
Universidade Federal do Paraná
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
0 Days to 360 Days
Healthy volunteers
No
Inclusion criteria
Tarsila Inpatient Study Inclusion Criteria * Infant born in Brazil. * Mother resident in Brazil during the related pregnancy. * Infant date of birth 14 days or more after start of the first national RSVpreF vaccination campaign to ensure potential to have been born to an RSVpreF-vaccinated mother. * Infant ≤360 days of age at time of RSV specimen collection. * Infant born at ≥37 weeks of gestational age. * Infant hospital admission for at least 24 hours with signs and symptoms meeting the case definition of ARI, defined as the presence of any of the following: nasal secretion for ≥24 hours; respiratory distress, labored breathing, or tachypnea (respiratory rate ≥60 breaths/min for infants \<2 months or ≥50 breaths/min for infants 2-12 months); cough; inability to feed for any period due to respiratory symptoms; apnea; or other relevant respiratory symptoms (examples include but are not limited to wheezing, crackles, and nasal flaring).
Exclusion criteria
* Maternal or infant receipt of any other licensed or investigational RSV preventive product. * Infant receipt of blood transfusion or other blood products containing antibodies since birth. * Infant previously enrolled in this study. * Lack of informed consent from the mother or the infant's legal guardian. * Absent or inconclusive RT-qPCR result for RSV. * Birth to a mother whose RSVpreF vaccination status could not be confirmed. Tarsila Outpatient Study Inclusion Criteria: * Infant born in Brazil. * Mother resident in Brazil during the related pregnancy. * Infant date of birth 14 days or more after start of the first national RSVpreF vaccination campaign to ensure potential to have been born to an RSVpreF-vaccinated mother. * Infant ≤360 days of age at time of RSV specimen collection. * Infant born at ≥37 weeks of gestational age. * Infant presentation to an outpatient healthcare facility with signs and symptoms meeting the case definition of ARI, defined as the presence of any of the following: nasal secretion for ≥24 hours; respiratory distress, labored breathing, or tachypnea (respiratory rate ≥60 breaths/min for infants \<2 months or ≥50 breaths/min for infants 2-12 months); cough; inability to feed for any period due to respiratory symptoms; apnea; or other relevant respiratory symptoms (examples include but are not limited to wheezing, crackles, and nasal flaring).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Lower respiratory Tract Disease (LRTD) Hospitalization among infants aged up to 180 days (Tarsila Inpatient Study) | Hospitalization occurring ≤180 days after birth | Hospitalization due to RT-qPCR-confirmed RSV-positive lower respiratory tract disease, defined as cough or difficulty breathing, symptom onset within the preceding 10 days, and at least one of the following: tachypnea (respiratory rate ≥60 breaths/min for infants \<2 months; ≥50 breaths/min for infants 2-12 months), oxygen saturation (SpO₂) \<95%, or chest wall indrawing). |
| Acute respiratory illness (ARI) among infants aged up to 180 days (Tarsila Outpatient Study) | Occurring ≤180 days after birth. | RT-qPCR-confirmed RSV-positive with signs and symptoms meeting the case definition of ARI, defined as the presence of any of the following: nasal secretion for ≥24 hours; respiratory distress, labored breathing, or tachypnea (respiratory rate ≥60 breaths/min for infants \<2 months or ≥50 breaths/min for infants 2-12 months); cough; inability to feed for any period due to respiratory symptoms; apnea; or other relevant respiratory symptoms (examples include but are not limited to wheezing, crackles, and nasal flaring). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Lower respiratory Tract Disease (LRTD) hospitalization among infants aged up to 180 days by subgroups (Tarsila Inpatient Study) | Hospitalization occurring ≤180 days after birth | RT-qPCR-confirmed RSV-positive LRTD hospitalization, analyzed by: * Gestational age at RSVpreF vaccination. * Time from RSVpreF vaccination to birth. * Time intervals of infant age at illness. |
| Severe Lower respiratory Tract Disease (LRTD) hospitalization among infants aged up to 180 days (Tarsila Inpatient Study) | Hospitalization occurring ≤180 days after birth | RT-qPCR-confirmed RSV-positive severe LRTD hospitalization, defined as LRTD plus at least one of the following: respiratory rate ≥70 breaths/min (if \<2 months) or ≥60 breaths/min (if ≥2 months); SpO₂ \<93%; requirement for high-flow oxygen, non-invasive, or invasive mechanical ventilation; intensive care unit (ICU) admission for \>4 hours; or unresponsiveness/loss of consciousness) . |
| Severe Lower respiratory Tract Disease (LRTD) hospitalization among infants aged up to 180 days by subgroups (Tarsila Inpatient Study) | Hospitalization occurring ≤180 days after birth | RT-qPCR-confirmed RSV-positive severe LRTD hospitalization, analyzed by: * Gestational age at RSVpreF vaccination. * Time from RSVpreF vaccination to birth. * Time intervals of infant age at illness. |
| Acute respiratory illness (ARI) among infants aged up to 180 days by Subgroups (Tarsila Outpatient Study) | ARI occurring ≤180 days after birth | RT-qPCR-confirmed RSV-positive ARI analyzed by: gestational age at RSVpreF vaccination, time from RSVpreF vaccination to birth, and time intervals of infant age at illness. |
Contacts
CONTACTMaicon Falavigna, MD PhD
PRINCIPAL_INVESTIGATORMaicon Falavigna
Inova Medical
Outcome results
None listed