We investigated the prevalence of human papillomavirus (HPV) infection and the distribution of high-risk HPV genotypes among 2,308 high-risk Korean women to predict how much the current prophylactic HPV vaccines might affect the prevention of cervical cancer in Korea. HPV DNA was detected in 939 women (40.7%) but only one-third of women were positive for HPV-16 and/or HPV-18, the genotypes used for developing the HPV vaccines. Thus, the development of area-specific HPV vaccines based on dominant HPV genotypes in our country is needed for preventing HPV infection and the development of premalignant lesions in the cervix of Korean women. FindingsInfection with certain types of human papillomavirus (HPV) is recognized as a causal and necessary factor for developing cervical cancer [1,2], which is the fourth of the most common cancer in South Korean women [3]. More than 140 different HPV genotypes have been characterized and approximately 50 of these genotypes are known to infect the genital tract and be oncogenic or high-risk (HR) types . HR genotypes are significantly associated with progression to invasive cervical cancer [2,4]. Therefore, assessment of the HPV genotypic spectrum among sexually active women is important for predicting public health problems such as the risks of developing cervical intraepithelial neoplasia and cervical cancer [5,6].HPV-16, the most common HR type, is detected in 50 -60% of high-grade squamous intraepithelial lesions and invasive cervical cancers and HPV-18 is followed by an incidence of 10 -20% [4,7]. Thus, HPV-16 and -18 are considered as the types responsible for causing most cervical cancers in many countries [4,7]. Clinical trials have reported that these vaccines can protect many uninfected women from developing precancerous cervical lesions caused by 9]. In spite of their high effectiveness to reduce the incidence of cervical cancer, the usefulness of these vaccines is still being debated because of the differences in the geographical distribution of HPV genotypes [10].Vaccines against HPV-16 and -18 have been developed to help the prevention of cervical cancer and the use of Merck's Gardasil (the quadrivalent vaccine for ) and GSK's Cervarix (the bivalent vaccine for HPV-16 and -18) have been licensed by the Korea Food and Drug Administration. Populationbased study for the distribution of HPV genotype is needed to predict how much these vaccines might influence to the prevention of cervical cancer.In the present study, the prevalence and distribution of HPV genotypes among high-risk women, which are called as commercial sex workers (CSWs) by other countries, were examined to predict whether the developed HPV vaccines are sufficient for preventing HPV infection and the development of premalignant lesions of the cervix in South Korea. A cohort of 2,308 high-risk women visiting for regular sexually transmitted infection testing in public health centers in four different regions (Seoul, Busan, Gwangju and Jeollanamdo) was enrolled in this study. Specimens were collecte...

Objectives Young children could act as important carriers of cefotaxime-resistant Enterobacteriaceae. However, most studies on these bacteria have focused on hospitalized adults. Therefore, we determined the prevalence and characteristics of ESBL-, plasmid-determined AmpC-type β-lactamase (PABL)- and carbapenemase-producing diarrhoeagenic Escherichia coli isolates mainly from infants and children in the south-west region of Korea over a 10 year period. Methods Non-duplicate E. coli clinical isolates were recovered from diarrhoeagenic patient specimens at 12 hospitals in Gwangju, Korea, between January 2007 and December 2016. Antimicrobial susceptibilities and molecular features of ESBL- and carbapenemase-producing isolates were determined. Results A total of 1047 pathogenic E. coli isolates were collected and 58 cefotaxime-resistant E. coli isolates (5.5%) were identified. The prevalence and types of β-lactamase genes increased steadily from 5.7% in 2007 to 11.6% in 2016 with some fluctuations. CTX-M-14 (53.4%) was the predominant CTX-M genotype. PFGE revealed high genetic heterogeneities among diarrhoeagenic E. coli isolates, suggesting horizontal transfer of antibiotic resistance genes, which was also proved by conjugation assay. Conclusions Progressive increases in carriage rates and the number of β-lactamase types, and the possibility of community outbreaks of these food-borne bacteria in young children, may pose tangible public health threats.

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Shiga toxin-producing Escherichia coli (STEC) strains are commensal bacteria in cattle and cause food borne disease in human. We analyzed the isolation rate of STEC in stool specimens of patients with diarrhea and in fecal samples of cattle in Gwangju, Korea. STEC strains were detected from 33 (0.19%) out of 17,148 patients with diarrhea while there has been a progressive increase in the incidence rate from 0.07% in 2004 to 0.33% in 2008. We investigated serotypes, shiga toxin genes, and antimicrobial resistance patterns of the 44 STEC isolates from human and cattle sources. The 33 STEC isolates from human belonged to 14 O serotypes including O157, O26 and O111. The 11 isolates from cattle belonged to 11 O serotypes. PCR detection for stx genes showed that 12 (27.3%) isolates carried stx 1 genes, 20 (45.5%) possessed stx 2 genes, and 12 (27.3%) carried both stx 1 and stx 2 . Of the 33 STEC isolates from human, 25 strains (76%) were resistant to one or more antibiotics. High level of resistance to tetracycline (73%) was most common, followed by ticarcillin and ampicillin (64%). But none of the 33 isolates from human were resistant to amikacin, cefazolin, cefepime, cefotetan, cefotaxime, ciprofloxacin, or imipenem. The 5 strains (45%) of the 11 isolates from cattle were resistant to at least one or three antibiotics but most of the isolates were sensitive to the 16 antibiotics employed in this survey. In conclusion, toxin types and serotypes of STEC isolated from human and cattle were diverse, and non-O157 STEC was also observed to be a greater proportion of STEC isolates. According to a specific comparison solely based on the toxin types and serotypes, most of the STEC strains isolated from cattle feces in Gwangju, Korea showed characteristics different from those isolated from patients. Therefore, laboratory surveillance is required to detect and carefully monitor the potentially hypervirulent STEC not only in human and cattle but also in other animals.

Since the first identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China in late December 2019, the coronavirus disease 2019 (COVID-19) has spread fast around the world. RNA viruses, including SARS-CoV-2, have higher gene mutations than DNA viruses during virus replication. Variations in SARS-CoV-2 genome could contribute to efficiency of viral spread and severity of COVID-19. In this study, we analyzed the locations of genomic mutations to investigate the genetic diversity among isolates of SARS-CoV-2 in Gwangju. We detected non-synonymous and frameshift mutations in various parts of SARS-CoV-2 genome. The phylogenetic analysis for whole genome showed that SARS-CoV-2 genomes in Gwangju isolates are clustered within clade V and G. Our findings not only provide a glimpse into changes of prevalent virus clades in Gwangju, South Korea, but also support genomic surveillance of SARS-CoV-2 to aid in the development of efficient therapeutic antibodies and vaccines against COVID-19.