Epidemiology and Transmission of Streptococcus Pneumoniae and Respiratory Syncytial Virus in Children and Elderly: a Household-based Prospective Cohort Study

A household-based prospective cohort study will be conducted from 2021 to 2025 in northern Taiwan. We will invite 240 households, having a baby who is discharged from MacKay children's Hospital. The households will be classified into nuclear family type and extended family type. The "Nuclear family type" is defined as husband and wife with baby (aged less than 5 months) and with or without children (2-5) and the "Extended family type" (three-generation family) is defined as husband and wife with baby (aged less than 5 months), children (2-5), and grandparents aged > 65 years old. We will initially complete an enrollment form to collect baseline data, including patient demographics, prior medical history, season when discharge, neonatal course and households. A LINE-based management will be done weekly by study team to see if there are any respiratory symptoms in household. In addition to the monthly physician weekly LINE response, the research nurse will contact the parents or legal guardians by telephone monthly for the 24 months to obtain data on changes in baseline information, and specific facts regarding possible respiratory infections after the last contact. If the households present with respiratory symptoms, the visit will be arranged as early as possible. When they presenting to the emergency department, outpatient clinic, or inpatient ward, the urine will be collected for the serotype-specific urinary antigen detection (SSUAD) assays and the nasopharyngeal or throat swab for polymerase chain reaction will be performed to study serotype of S. pneumoniae and Respiratory syncytial virus subgroup. If the subjects who have clinical syndromes suggestive of pneumonia or bronchopneumonia, they will be asked to participate in the further study along with their household family members. Nasopharyngeal aspiration, urine, blood, and induced sputum will be collected for cultures, polymerase chain reaction and serological test. Clinical manifestations, disease course, and outcomes will be recorded. Family members in the same household will asked to undergo screening with a nasopharyngeal or throat swab and urine sample. We will trace back 2-week contact history of children in nuclear family who get Respiratory syncytial virus or pneumococcal infections, especially focus on other family members. The data will be further analyzed to evaluate the influence of short period and long period contact.