Pneumococcal nasopharyngeal carriage in Indonesia infants and toddlers post-PCV13 vaccination in a 2+1 schedule: A prospective cohort study

Abstract

Background The PCV13 immunization demonstration program began in October 2017 in Indonesia. The aim of this study is to assess the dynamic changes of pneumococcal serotype before and after PCV13 administration, with two primary and one booster doses. Methods The prospective cohort study was conducted as a follow up study measuring the impact of PCV13 demonstration program by the Indonesian Ministry of Health in Lombok Island, West Nusa Tenggara, Indonesia, from March 2018 to June 2019. The subjects were two-month-old healthy infants who were brought to the primary care facility for routine vaccination and followed until 18 months of age. We use convenience sampling method. There were 115 infants in the control group and 118 infants in the vaccine group, and the PCV immunization was given on a 2+1 schedule. Nasopharyngeal (NP) swabs were collected four times during the vaccination periods by trained medical staff. Specimens were analyzed by culture methods to detect S. pneumonia colonization and multiplex polymerase chain reaction (mPCR) to determine serotype. The most frequently detected serotypes will be named as dominant serotypes. Descriptive analysis of demographic characteristics, the prevalence of overall and serotype colonization, and the distribution of serotypes were performed. The prevalence of both cohort groups were compared using chi-square test. Statistical significance was set at p < 0.05. Results Two hundred and thirty three infants age two months old were recruited, with 48.9% of the subjects were male and 51.1% of the subjects were female. Sociodemographic data in both cohort groups were relatively equal. Nasopharyngeal pneumococcal colonization before PCV13 administration occurred in 19.1% of the control and 22.9% of the vaccine group. The prevalence increased with increasing age in both groups. The prevalence of VT serotypes in control groups aged 2 months, 4 months, 12 months, and 18 months was 40.9%, 44.2%, 53.8%, and 54.3%, respectively, and in the vaccine group, 25.9%, 40.4%, 38.0%, and 22.6%, respectively. The most common VT serotypes in both groups were 6A/6B, 19F, 23F, and 14. The prevalence of VT serotypes decreased significantly compared to non-vaccine type serotypes after three doses of the PCV13 vaccine (p < 0.001). Another notable change was the decline in prevalence of serotype 6A/6B after PCV13 administration using the 2+1 schedule. Conclusions This study shows lower prevalence of VT and 6A/6B serotypes in the nasopharynx among children who were PCV13 vaccinated compared with those who were unvaccinated. The result from this study will be the beginning of future vaccine evaluation in larger population and longer period of study.

Nasopharyngeal carriage of Streptococcus pneumoniae among children <5 years of age in Indonesia prior to pneumococcal conjugate vaccine introduction

“…These study findings suggest the introduction of PCV13 has the potential to provide large benefits in protecting children against pneumococcal infection and supports the decision made by the Indonesian government to introduce PCV13 into the routine childhood vaccination schedule. PCV13 use in Indonesia started with a demonstration program in 2017 covering two provinces (West Nusa Tenggara and Bangka Belitung) [20], with a broader scale introduction launched in select districts of East and West Java in 2021. Nationwide introduction started in September 2022 [21].…”

Epidemiology of Haemophilus influenzae in children on Lombok Island, Indonesia

“…Archived nasopharyngeal (NP) swab specimens from a previous prospective cohort pneumococcal carriage study on Lombok Island, West Nusa Tenggara, Indonesia, conducted between March 2018 and June 2019, were used [ 9 ]. The study enrolled healthy infants (2 months old) who were brought to the primary care facility for routine vaccination and were randomized into two groups: pneumococcal vaccine (PCV)-vaccinated group and the non-PCV-vaccinated group (control group).…”

“…The two groups were matched based on age and home location. All recruited children were healthy when the NP swab specimens were obtained [ 9 ]. In the current study, we randomly sampled 96 of 233 archived NP swab specimens from both the vaccine (64 specimens) and control (32 specimens) groups, which were obtained 6 months after the PCV vaccine booster was administered to the vaccine group.…”

“…The laboratory results were summarized as the total prevalence of carriage and the distribution of serotypes among the positive results. We also reviewed relevant provenance data collected using a questionnaire developed in a previous study, which included the following variables: sex, nutritional status, number of people in the household and cigarette smoke exposure [ 9 ].…”

Whole genome sequencing data of Streptococcus pneumoniae isolated from Indonesian population

“…These isolates were obtained from blood ( n = 14), pleural fluid ( n = 6), cerebrospinal fluid ( n = 9), bronchoalveolar lavage fluid ( n = 1), sputum ( n = 7) and nasopharyngeal swab specimens ( n = 45). The isolates were obtained from Banjarmasin ( n = 4), Kotabaru ( n = 9), Medan ( n = 6), Surabaya ( n = 34), Semarang ( n = 10), Jakarta ( n = 10), Lombok ( n = 3), Makasar ( n = 13), and Manado ( n = 5), Indonesia as reported previously [5] , [6] , [7] , [8] . All isolates were collected from 2012 to 2019.…”