Latar Belakang. Rotavirus merupakan penyebab diare berat pada anak balita di negara maju dan negara berkembang serta banyak menyerang anak berusia 3-24 bulan. Di daerah tropis, rotavirus terjadi sepanjang musim dengan hanya ada sedikit variasi. Usaha pencegahan dengan perbaikan hygine dan sanitasi tidak banyak mengurangi morbiditasnya, sehingga penggunaan vaksin merupakan salah satu pilihan terbaik. Agar memberikan proteksi maksimal, maka sebelum penerapan vaksin perlu dilakukan penelitian untuk mengetahui beban sakit akibat rotavirus, jenis genotype rotavirus yang bersirkulasi di populasi serta karakteristik rotavirus penyebab infeksi. Oleh karena itu, dilakukan penelitian ini untuk menganalisis: (1) prevalensi diare rotavirus pada anak balita di Indonesia, (2) kelompok umur yang paling sering terserang diare rotavirus, (3) kecenderungan terjadinya diare rotavirus terhadap musim (4) distribusi genotype rotavirus yang beredar di Indonesia, (5) dinamika perubahan genotype rotavirus di Indonesia, (6) gambaran electropherotype rotavirus isolat Indonesia, (7) filogenetik gen VP4, VP7, NSP2, NSP4 dan NSP5 rotavirus isolat Indonesia, (8) variasi asam amino penyusun gen VP4, VP7, NSP2, NSP4, dan NSP5 rotavirus isolat Indonesia dibanding isolat negara lain yang sekuennya disimpan di GenBank , dan (9) variasi asam amino penyusun gen VP4 dan VP7 rotavirus isolat Indonesia dibanding isolat penyusun vaksin. Metode: Penelitian ini merupakan repeated cross sectional study yang dilakukan di 7 rumah sakit di 6 kota berbeda di Indonesia. Anak balita penderita diare akut yang dirawat di rumah sakit tersebut diambil sampel feses dan data epidemiologisnya. Deteksi rotavirus dilakukan dengan enzyme immunoaasay dan deteksi genotype dengan RT-PCR. Pola migrasi RNA rotavirus diketahui dengan elektroforesis pada PAGE. Sekuensing dilakukan untuk mengetahui nukleotida penyusun gen VP4, VP7, NSP2, NSP4, dan NSP5. Analisis filogenetik dan analisis perbandingan asam amino penyusun gen dilakukan dengan menggunakan program MEGA 5.1. Hasil Penelitian: Selama periode 1 Januari – 31 Desember 2006 dan 1 Januari 2009 – 31 Desember 2010 telah terkumpul 5.013 sampel penderita diare yang dirawat di 7 rumah sakit dan 2.676 (53,38%) di antaranya rotavirus positip. Dari 669 sampel yang di-genotyping, diketahui G1P[6], G1P[8], dan G2P[4] sebagai genotype yang dominan bersirkulasi di Indonesia. Dari 70 sampel yang dianalisis profil RNAnya, diketahui 83% mempunyai long pattern dan 17% mempunyai short pattern. Sekuensing gen VP4 dilakukan pada 3 isolat P[4] dan 12 isolat P[8]; gen VP7 pada 6 isolat G1, 4 isolat G2, dan 8 isolat G9; gen NSP2 pada 2 isolat, Gen NSP4 pada 3 isolat, dan gen NSP5 pada 1 isolat. Kesimpulan: Berdasarkan hasil penelitian ini disimpulkan: (1) prevalensi diare rotavirus pada anak balita di Indonesia berkisar antara 29 - 67%, (2) rotavirus paling sering menyerang anak berumur 6-23 bulan, (3) diare rotavirus di Indonesia terjadi sepanjang tahun, dan tidak tergantung musim, (4) genotype rotavirus yang dominan beredar di Indonesia adalah G1P[6], G1P[8], dan G2P[4], (5) genotype rotavirus di Indonesia selalu berubah proporsinya, (6) rotavirus isolat Indonesia menunjukkan gambaran spesifik electropherotype Rotavirus A dan 83% sampel mempunyai RNA long pattern, (7) berdasarkan hasil analisis filogenetik didapatkan: isolat G1 Indonesia termasuk lineage I, isolat G2 termasuk lineage II, isolat G9 termasuk lineage III, isolat P[4] termasuk lineage V, isolat P[8] termasuk lineage III, (8) terdapat variasi pada asam amino penyusun gen VP4, VP7, dan NSP4 rotavirus isolat Indonesia apabila dibanding dengan isolat negara lain yang dipublikasi di GenBank, dan (9) terdapat variasi pada asam amino penyusun gen VP4 dan VP7 rotavirus isolat Indonesia apabila dibanding dengan isolat penyusun vaksin.

Background: Rotavirus is the most frequent cause of severe diarrhea in children under five years of age both in developed and developing countries. The highest incidence of rotavirus infection is found among children by 3-24 months of age. In tropical countries, rotavirus infection occurs throughout the year with only slight variation across different seasons. Implementation of diarrhea prevention program by improving hygiene and sanitation improvements could not reduce the morbidity rate. Therefore, vaccination is believed to be an alternative to reduce mortality and morbidity of rotavirus infection. Prior to the introduction of a rotavirus vaccine, initial study is required to assess the burden of rotavirus infection, to map the genotypes of rotavirus, as well as the epidemiologic characteristics and virulence of rotavirus within population. Therefore, this study aims to investigate: (1) the prevalence of diarrhea due to rotavirus infection in various regions in Indonesia, (2) specific age group that most frequently suffers from rotavirus related diarrhea, (3) the variability of rotavirus diarrhea by seasonality, (4) the electropherotype profiles of Indonesian rotavirus isolates, (5) the distribution of rotavirus genotypes circulating in various regions in Indonesia, (6) the dynamic changes of rotavirus genotypes circulating in various regions in Indonesia, (7) the of VP4, VP7, NSP2, NSP4, and NSP5 genotypes of rotavirus strains circulating in Indonesia compared to those of other countries using phylogenetic analysis (8) amino acid variations encoded by VP4, VP7, NSP2, NSP4, and NSP5 genes of rotavirus strains in Indonesia compared to those in other countries as available in GenBank, and (9) the variation of amino acid composition at VP7 epitopes in rotavirus variants in Indonesia in comparison to those targeted by vaccine. Methods: The study was conducted in 7 hospitals in 6 different cities in Indonesia. Stool samples and epidemiologic data were collected from children under five years old who were hospitalized due to diarrhea. Rotavirus in the stools was detected by enzyme immunoassay and then genotyped using RTPCR. Rotavirus RNA migration pattern was determined by PAGE electrophoresis. Sequencing was used to determine the genotypes of VP4, VP7, NSP2, NSP4, and NSP5. Phylogenetic analysis was performed with neighbor-joining method by using MEGA 5.1. Results: During the period from January to December 2006 and between January 2009 and December 2010, there were 5,013 samples of patients with diarrhea who were hospitalized in those 7 hospitals. Of those, 2,676 (53.38%) were rotavirus positive. Of 669 samples, G1P[6], G1P[8], and G2P[4] were detected as the dominant genotypes circulating in Indonesia. RNA profile analysis showed that 83% had long pattern and 17% had short pattern (n=70). Sequencing of VP4 gene was performed in 3 isolates of P[4] and 12 isolates of P[8]. In addition, sequencing analysis of VP7 gene sequencing was completed in 6 isolates of G1, 4 isolates of G2 , 8 isolates of G9, and 2 isolates of NSP2 gene, 3 isolates of NSP4 gene, and 1 isolate of NSP5 gene. Conclusion: Our present data suggest that (1) the prevalence of diarrhea due to rotavirus in children under five years of age in Indonesia ranges between 29- 67%, (2) rotavirus most often affects children by the age of 6-23 months, (3) rotavirus diarrhea in Indonesia occurs throughout the year, and does not depend on seasonality, (4) Indonesian rotavirus isolates demonstrate electropherotype-specific pattern of Rotavirus A and 83% of isolates have longpattern, (5) the dominant rotavirus genotypes circulating in Indonesia are G1P[6], G1P[8], and G2P[4], (6) rotavirus genotypes circulating in various regions in Indonesia always change in proportions, (7) based on the results of phylogenetic analysis of the VP7 gene, Indonesian G1 isolates are included in lineage I, G2 isolates are included in lineage II and G9 isolates are included in lineage III. While based on phylogenetic analysis of the gene VP4, it is known that Indonesian P[4] isolates are included in lineage V and P[8] isolates are included in lineage III, (8) there are variations in the amino acid composition of the Indonesian VP4, VP7, and NSP4 genes when compared with other countries’ isolates published in GenBank, and (9) there are variations in the amino acid composition of the Indonesian VP7 gene when compared with the vaccine strains.

Kata Kunci : rotavirus, genotyping, VP4, VP7, NSP2, NSP4, NSP5