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Rotavirus (RV), Norovirus (NV), Sapovirus (SaV) and Astrovirus (Ast) are the leading causes of gastroenteritis and mortality in children worldwide. RV vaccines help to reduce the burden of diarrhea while the importance of other viruses is increasing. Therefore, we conducted a cross-sectional descriptive study to determine prevalence of these viruses in hospitalized children under 5 years old in Nam Dinh province with approximately 80% of RV vaccine coverage. We randomly selected 579 (25%) among diarrheal samples collected in 4 district hospitals from Dec. 2017 to Nov. 2019. An ELISA kit was employed to detect RV and the multiplex real-time RT-PCR with specific primers to detect NV, SaV and Ast. These viruses were found among 64.3% of hospitalized children, of which NV and RV were present in 28.5% and 21.4%, respectively, while SaV and Ast were detected in 3.3% and 2.6%, respectively. Co-infections accounted for 8.5%, mainly among RV and 3 other viruses. There is a significant difference in RV and NV positive rates between vaccinated and unvaccinated groups (p < 0.001 and p = 0.008, respectively). This study contributed to the understanding of the potential impact of rotavirus vaccine on other diarheal pathogens and emphasize the need for further epidemiological studies when the nationwide RV vaccination in Vietnam is implementing.

High-risk human papillomavirus (HPV) genotypes are the leading causes of anogenital cancer, including cervical cancer. Screening these genotypes will potentially alleviate the disease burden that HPV causes. Therefore, NIHERealtime PCR hrHPV was developed based on the principle of multiplex real-time PCR. The objective of this study is to establish the specifcations of this assay in detecting and identifying 14 high-risk genotypes of HPV. The specifcations of this assay including cross-reactivity, sensitivity and specifcity, the limit of detection and stability, were evaluated with clinical samples, HPV positive control code 06/202 and 06/206 (National Institute for Biological Standards and Control) and in-house plasmids. Four different real-time systems and two commercial assays were applied for comparison. No cross detection of bacteria and viruses related to other genital-anal was observed. The sensitivity and the specifcity of this kit both reached 100% for HPV-18, 92.3% and 100% for HPV-16, and ranged from 90.0% - 100% for the other 12 high-risk genotypes (n = 92) with the detection limit of 5 copies/µl for HPV-16 and HPV-18, and 10 copies/µl for the other 12 high-risk genotypes HPV. This test was stable for up to 12 months under -20oC condition. Equivalent performance was demonstrated on all four real-time systems. Finally, the product was highly comparable with the Sacace kit, Italy (HPV Genotypes 14 Real-™ Quant, V67-100FRT), evaluated by the World Health Organization. The NIHE kit has the potential to be used in the early detection of HPV infection to improve control, prevention and treatment of HPV-related anogenital diseases.