Characterization of Multidrug Resistant serogroup 19 Streptococcus pneumoniae isolated from the healthy children below five years of age in Indonesia

We investigated the resistance genes, pilus islet, biofilm formation ability, and sequence types of multidrug-resistant Streptococcus pneumoniae (MDRSP) isolated from the healthy children below 5 years of age in Indonesia. In all, 104 archived MDRSP isolates from previous carriage study in Indonesia in 2016-2019 were screened for the presence of antibiotic resistance genes and the rrgC (pilus islet 1) and pitB (pilus islet 2) genes. Multilocus sequence typing and biofilm formation was determined by PCR-Sequencing and the ability of cells to adhere to the walls, respectively. Results have shown that the mefA, ermB, and tetM genes were found in 93%, 52%, and 100% of MDRSP isolates respectively. The insertion of arginine, proline, and Ile-100-Leu were the most common mutations in the folA and folP genes. Pilus islet 1 and type 2 were discovered in 93% and 82% of MDRSP isolates respectively. The MDRSP isolates showed no biofilm formation ability (64%), and five out of ten strains of MDRSP strains were ST1464. This finding can be used to provide further considerations in implementing and monitoring pneumococcal vaccination in Indonesia.