Long-term sentinel surveillance of enteroviruses in Gwangju, South Korea, 2011-2020.

Human enteroviruses (EVs) are associated with a broad spectrum of diseases. To understand EV epidemiology, we present longitudinal data reflecting changing EV prevalence patterns in South Korea. We collected 7160 specimens from patients with suspected EV infections in ten hospitals in Gwangju, Korea during 2011-2020. RNA extraction and real-time reverse transcription polymerase chain reaction using EV-specific probes and primers were performed. EV genotyping and phylogenetic analysis were performed; EVs were detected in 3076 samples (43.0%), and the annual EV detection rate varied. EV infection rates did not differ with sex, and children aged ≤ 4 years were the most prone to EV infection; this trend did not change over time. Overall, 35 different EV types belonging to four distinctive species and rhinoviruses were identified. Although serotype distribution changed annually, the most frequently observed EVs were EV-A71 (13.1% of the cases), CVA6 (8.3%), CVB5 (7.6%), CVA16 (7.6%), CVA10 (7.5%), E18 (7.5%), E30 (7.0%), and E11 (5.0%) during 2011-2020. The predominant EV genotypes by clinical manifestation were CVB5 for aseptic meningitis; EV-A71 for hand, foot, and mouth disease cases; and CVA10 for herpangina. These results will aid the development of vaccines against EV infection and allow comprehensive disease control.

Emerging hantavirus infection in wild rodents captured in suburbs of Gwangju Metropolitan City, South Korea.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses is a frequently reported acute hemorrhagic fever in South Korea. These viruses are transmitted by various rodent species such as Apodemus agrarius. METHODOLOGY/PRINCIPAL FINDINGS: To investigate hantavirus infection and seroprevalence in rodents, wild rodents were captured from two districts in the suburbs of Gwangju Metropolitan City from January 2016 to December 2018. Nested reverse-transcription polymerase chain reaction (RT-PCR) targeting the hantavirus-specific L segment and indirect immunofluorescence antibody (IFA) assay using Hantaan virus antigen slides were performed. A total of 585 wild rodents were captured-512 A. agrarius, 49 Crocidura lasiura, and 24 Myodes regulus. Nested RT-PCR was performed to examine the rate of hantavirus infection in wild rodents, and 1.88% (11/585) of all rodents, 1.17% (6/512) of A. agrarius, 6.12% (3/49) of C. lasiura, and 8.33% (2/24) of M. regulus tested positive. The nucleotide sequence analysis of the eleven PCR-positive products revealed that six PCR products showed over 85% sequence similarity with the Jeju virus, four showed over 99.7% similarity with the Hantaan virus, and one showed over 95.3% homology with the Imjin virus. Moreover, IgG antibodies against the Hantaan virus were detected in 6.15% (36/585) of all rodents, 6.8% (35/512) of A. agrarius, and 4.17% (1/24) of M. regulus. IgG antibodies were not detected in C. lasiura. CONCLUSIONS/SIGNIFICANCE: Hantaviruses were detected in all three wild rodent species of A. agrarius, C. lasiura, and M. regulus captured in the suburbs of Gwangju Metropolitan City, South Korea, and it was demonstrated that they were various strains of hantaviruses such as the Hantaan, Jeju, and Imjin viruses.

First report of Borrelia burgdorferi sensu stricto detection in a commune genospecies in Apodemus agrarius in Gwangju, South Korea.

Lyme disease is a tick-borne infectious disease caused by the Borrelia burgdorferi sensu lato complex. However, the distribution of Borrelia genospecies and the tissue detection rate of Borrelia in wild rodents have rarely been investigated. Here, we studied 27 wild rodents (Apodemus agrarius) captured in October and November 2016 in Gwangju, South Korea, and performed nested polymerase chain reaction targeting pyrG and ospA to confirm Borrelia infection. Eight rodents (29.6%) tested positive for Borrelia infection. The heart showed the highest infection rate (7/27; 25.9%), followed by the spleen (4/27; 14.8%), kidney (2/27; 7.4%), and lungs (1/27; 3.7%). The B. afzelii infection rate was 25.9%, with the highest rate observed in the heart (7/27; 25.9%), followed by that in the kidney and spleen (both 2/27; 7.4%). B. garinii and B. burgdorferi sensu stricto were detected only in the spleen (1/27; 3.7%). This is the first report of B. burgdorferi sensu stricto infection in wild rodents in South Korea. The rodent hearts showed a high B. afzelii infection rate, whereas the rodent spleens showed high B. garinii and B. burgdorferi sensu stricto infection rates. Besides B. garinii and B. afzelii, B. burgdorferi sensu stricto may cause Lyme disease in South Korea.

Deep Learning Ensemble Method for Classifying Glaucoma Stages Using Fundus Photographs and Convolutional Neural Networks.

Purpose: This study developed and evaluated a deep learning ensemble method to automatically grade the stages of glaucoma depending on its severity.Materials and Methods: After cross-validation of three glaucoma specialists, the final dataset comprised of 3,460 fundus photographs taken from 2,204 patients were divided into three classes: unaffected controls, early-stage glaucoma, and late-stage glaucoma. The mean deviation value of standard automated perimetry was used to classify the glaucoma cases. We modeled 56 convolutional neural networks (CNN) with different characteristics and developed an ensemble system to derive the best performance by combining several modeling results.Results: The proposed method with an accuracy of 88.1% and an average area under the receiver operating characteristic of 0.975 demonstrates significantly better performance to classify glaucoma stages compared to the best single CNN model that has an accuracy of 85.2% and an average area under the receiver operating characteristic of 0.950. The false negative is the least adjacent misprediction, and it is less in the proposed method than in the best single CNN model.Conclusions: The method of averaging multiple CNN models can better classify glaucoma stages by using fundus photographs than a single CNN model. The ensemble method would be useful as a clinical decision support system in glaucoma screening for primary care because it provides high and stable performance with a relatively small amount of data.

The Long-Term Impact of Rotavirus Vaccines in Korea, 2008-2020; Emergence of G8P[8] Strain.

This study evaluated the long-term impact of rotavirus vaccination on prevalence, seasonality, and genotype distribution in Gwangju, Korea for 13 seasons. Rotavirus was identified using ELISA and then sequenced for G and P genotypes by Reverse Transcription Polymerase Chain Reactions for diarrhoeagenic patient specimens from local hospitals between January 2008 and August2020. Of 26,902 fecal samples, 2919 samples (10.9%) were ELISA positive. The prevalence declined from 16.3% in pre-vaccine era to 5.4% in post-vaccine era. In the pre-vaccine period, G1P[8] was the most common genotype, followed by G2P[4], G3P[8], and G9P[8], etc. In the transitional period, the proportion of G2P[4] became the dominant genotype and G1P[8] was still commonly identified. In contrast, the novel genotype G8P[8] was predominant in the post-vaccine period. Meanwhile, G2P[4] and G8P[8] were major genotypes in both Rotarix and RotaTeq groups. The substantial decline of G1P[8] prevalence, reemergence of G1P[8], G3P[8], and G2P[4] rotavirus strains, and surge of the rare G8P[8] after vaccine introduction were interesting points to note. The continuous surveillance on the genotypes of RV will be needed to understand rotavirus epidemiology and their evolutionary patterns, as caution is required when interpreting temporal changes in RV genotype dynamic.

Pesticide Residues and Risk Assessment from Monitoring Programs in the Largest Production Area of Leafy Vegetables in South Korea: A 15-Year Study.

Leafy vegetables are widely consumed in South Korea, especially in the form of kimchi and namul (seasoned vegetables) and are used for wrapping meat. Therefore, the management of pesticide residues in leafy vegetables is very important. A total of 17,977 samples (49 leafy vegetables) were mainly collected in the largest production area of leafy vegetables (Gwangju Metropolitan City and Chonnam Province) in South Korea. They were analyzed within the government's monitoring programs (Gwangju Metropolitan City) of pesticide residues between 2005 and 2019. Pesticide residues were found in 2815 samples (15.7%), and 426 samples (2.4%) from among these exceeded the specified maximum residue limits (MRLs). Samples exceeding the MRLs were mostly detected in spinach, ssamchoo (brassica lee ssp. namai), crown daisy, lettuce, and perilla leaves. Azoxystrobin, dimethomorph, and procymidone were the most frequently detected pesticides. However, procymidone, diniconazole, and lufenuron were found to most frequently exceed the MRLs. The rate of MRLs exceeding has been managed below the average (2.4%) more recently than in the past in this area. Further, leafy vegetables with the most violations of the MRLs in our study in South Korea were not harmful to health by a risk assessment (the range of the hazard index was 0.001-7.6%).

Genomic and phylogenetic analyses of SARS-CoV-2 strains isolated in the city of Gwangju, South Korea

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.

Epidemiological Characteristics of Rodents and Chiggers with Orientia Tsutsugamushi in the Republic of Korea.

A survey of rodents and chiggers associated with Orientia tsutsugamushi was conducted in a rural region of the Republic of Korea (Korea) between 2014 and 2018. Overall Apodemus agrarius 15.2% had the highest seropisitive for O. tsutsugamushi, followed by Myodes regulus 11.4%. Monthly risk factors using logistic regression analysis were not associated with O. tsutsugamushi infections in rodents. The overall prevalence rate of O. tsutsugamushi among chiggers was 0.3%. The chigger (Leptotrombidium scutellare) and monthly (October) risk factors were associated with O. tsutsugamushi human infections (P<0.05). Orientia tsutsugamushi infections are endemic in rodents in Korea and people, for example, soldiers who are active outdoors, must employ preventive measures, especially during October (P<0.05). When there are many reports of O. tsutsugamushi infections in Korea. The Boryong strain 85.7% (2/14) was the most common strain detected in chiggers, followed by the Shimokoshi 7.1% (1/14) and Karp 7.1% strains.

Epidemiological Characteristics of Field Tick-Borne Pathogens in Gwang-ju Metropolitan Area, South Korea, from 2014 to 2018.

OBJECTIVES: The importance of tick-borne diseases is increasing because of climate change, with a lack of long-term studies on tick-borne pathogens in South Korea. To understand the epidemiological characteristics of tick-borne diseases, the monthly distribution of field ticks throughout the year was studied in South Korea between May 2014 and April 2018 in a cross sectional study. METHODS: The presence of various tick-borne pathogens (Rickettsia species, Borrelia species, Anaplasma phagocytophilum) was confirmed by using polymerase chain reaction, to provide information for a prevention strategy against tick-borne pathogenic infections, through increased understanding of the relationship between seasonal variation and risk of infection with Rickettsia species. This was performed using logistic regression analysis (SPSS 20, IBM, USA) of the data obtained from the study. RESULTS: During the study period there were 11,717 ticks collected and 4 species identified. Haemapysalis longicornis was the most common species (n = 10,904, 93.1%), followed by Haemapysalis flava (n = 656, 5.6%), Ixodes nipponensis (n = 151, 1.3%), and Amblyomma testudinarium (n = 6, 0.05%) The results of this cross-sectional study showed that Haemapysalis flava carried a higher risk of transmission of Rickettsia species than other tick species (p < 0.05). CONCLUSION: In conclusion, due attention should be paid to preventing tick-borne infections in humans whilst engaged in outdoor activities in Spring and Autumn, particularly in places where there is a high prevalence of ticks.

Severe Fever with Thrombocytopenia Syndrome Associated with Manual De-Ticking of Domestic Dogs.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease. SFTS is caused by the SFTS virus, a novel phlebovirus, and is spread by ticks. Methods: A 50-year-old man was admitted to our hospital with the chief complaint of fever and was diagnosed with confirmed SFTS. An epidemiological investigation was conducted, and immunofluorescent antibody assays (IFAs) were performed to determine the role of the patient's three dogs in the transmission. PCR assays were performed using ticks that were collected with the dragging and flagging method from the patient's dogs and home. Results: PCR results were positive, and IFA confirmed an increased antibody titer. Although the reverse transcription PCR results of the three dogs were negative for SFTS virus, one dog had an elevated SFTS IFA immunoglobulin G (IgG) titer of 1:1,024. Moreover, a number of ticks were observed in the area surrounding the dog cages. Based on the findings of the patient interview, the patient was likely to have acquired SFTS by blood splash because he removed or burst ticks from the dogs with his bare hands. Although no tick bites were reported, tick transmission could not be ruled out. Studies have shown that only one in three individuals with a diagnosis of SFTS recalls a tick bite; thus, a definite exclusion of tick transmission in this case was not possible. Conclusions: The epidemiological findings of our case suggest a possible relationship between tick infestation in domestic dogs and SFTS virus transmission to humans. However, there is no direct evidence supporting this viral transmission route. Future studies are needed to further investigate a potential route of SFTS transmission by exposure to engorged tick blood or pet dogs.

Prevalence of Orientia tsutsugamushi, Anaplasma phagocytophilum and Leptospira interrogans in striped field mice in Gwangju, Republic of Korea.

This study investigated the prevalence of Orientia tsutsugamushi, Anaplasma phagocytophilum, and Leptospira interrogans in wild rodents through molecular detection using organ samples and through serological assay using blood samples of mice collected from two distinct sites in Gwangju Metropolitan City, Republic of Korea (ROK). A total of 47 wild rodents, identified as Apodemus agrarius (A. agrarius), were captured from June to August 2016. The seroprevalence of antibodies against bacterial pathogens in A. agrarius sera was analyzed; 17.4% (8/46) were identified as O. tsutsugamushi through indirect immunofluorescence assay and 2.2% (1/46) were identified as Leptospira species through passive hemagglutination assay. Using polymerase chain reaction, the spleen, kidney and blood samples were investigated for the presence of O. tsutsugamushi, A. phagocytophilum, and L. interrogans. Out of the 47 A. agrarius, 19.1% (9/47) were positive for A. phagocytophilum and 6.4% (3/47) were positive for L. interrogans, while none were positive for O. tsutsugamushi. Four out of 46 (8.7%) blood samples, six out of 45 (13.3%) spleen samples, and one out of 47 (2.1%) kidney samples were positive for A. phagocytophilum. Three out of 47 (6.4%) kidney samples were positive for L. interrogans. The sequencing results of PCR positive samples demonstrated > 99% similarity with A. phagocytophilum and L. interrogans sequences. A. phagocytophilum was mostly detected in the spleen, whereas L. interrogans was mostly detected in the kidneys. Notably, A. phagocytophilum and L. interrogans were detected in A. agrarius living in close proximity to humans in the metropolitan suburban areas. The results of this study indicate that rodent-borne bacteria may be present in wild rodents in the metropolitan suburban areas of ROK.

Detection of Borrelia miyamotoi in Ixodes nipponensis in Korea.

BACKGROUND: This study investigated Borrelia species prevalence in ticks from vegetation, through a molecular method, in Gwangju Metropolitan City, South Korea. METHODOLOGY/PRINCIPAL FINDINGS: A total of 484 ticks were collected through flagging and dragging in a suburban area of Gwangju Metropolitan City, South Korea, in 2014. These ticks were morphologically identified and subjected to nested PCR, targeting Borrelia-specific CTP synthase (pyrG), outer surface protein A (ospA) and flagellin (flaB) genes. Molecular biological species identification of Borrelia-positive ticks was conducted via 16S rRNA PCR assays. Of the 484 ticks collected, 417 (86.2%) were identified as Haemaphysalis longicornis, 42 (8.7%) as H. flava, and 25 (5.2%) as Ixodes nipponensis. All the ixodid ticks containing Borrelia species bacteria were confirmed to be I. nipponensis adults, by both morphological and molecular methods. Of the 25 I. nipponensis ticks collected, four (16%) were positive for Borrelia species, three of which were B. afzelii and one B. miyamotoi. CONCLUSIONS/SIGNIFICANCE: Our study has shown the harboring of B. miyamotoi by I. nipponensis in South Korea. Morphological and molecular genetic analyses revealed that, in South Korea, I. nipponensis could potentially transmit B. miyamotoi to humans.

Prevalence and molecular epidemiology of ESBLs, plasmid-determined AmpC-type ß-lactamases and carbapenemases among diarrhoeagenic Escherichia coli isolates from children in Gwangju, Korea: 2007-16.

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 ß-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 ß-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 ß-lactamase types, and the possibility of community outbreaks of these food-borne bacteria in young children, may pose tangible public health threats.

Molecular detection of viruses causing hemorrhagic fevers in rodents in the south-west of Korea.

Many pathogens causing hemorrhagic fevers of medical and veterinary importance have been identified and isolated from rodents in the Republic of Korea (ROK). We investigated the occurrence of emerging viruses causing hemorrhagic fevers, such as hemorrhagic fever with renal syndrome (HFRS), severe fever with thrombocytopenia syndrome (SFTS), and flaviviruses, from wild rodents. Striped field mice, Apodemus agrarius (n = 39), were captured during 2014-2015 in the south-west of ROK. Using molecular methods, lung samples were evaluated for SFTS virus, hantavirus, and flavivirus, and seropositivity was evaluated in the blood. A high positive rate of hantavirus (46.2%) was detected in A. agrarius lungs by reverse transcription-nested polymerase chain reaction (RT-N-PCR). The monthly occurrence of hantavirus was 16.7% in October, 86.7% in November, and 25% in August of the following year (p < 0.001). Moreover, 17.9% of blood samples were serologically positive for hantavirus antibodies. The most prevalent strain in A. agrarius was Hantaan virus. All samples were positive for neither SFTS virus nor flavivirus. Hantaan virus was detected in 86.7% of A. agrarius in November (autumn), and thus, virus shedding from A. agrarius can increase the risk of humans contracting HFRS. These findings may help to predict and prevent disease outbreaks in ROK.

First detection and identification of Candidatus Neoehrlichia mikurensis in South Korea.

Candidatus Neoehrlichia mikurensis (Ca. N. mikurensis; family Anaplasmataceae) is an emerging tick-borne pathogen that causes a systemic inflammatory syndrome with thrombotic complications. We report here the first identification of Ca. N. mikurensis in organ samples from small mammals captured in southwest South Korea. Nested PCR of groEL and 16S rRNA genes was used to confirm the identity of the bacteria present, and successfully amplified fragments were sequenced. All captured animals were identified as striped field mice (Apodemus agrarius), approximately 28.6% (4/14) and 21.4% (3/14) of which were found to be PCR-positive for Ca. N. mikurensis and Anaplasma phagocytophilum, respectively. The detection of Ca. N. mikurensis in these animals represents the first evidence of this pathogen in South Korea. Carriage of this bacterium by rodents highlights the need for more detailed investigation of their role in its transmission to humans.

Long-term comparison of postoperative refractive outcomes between phacotrabeculectomy and phacoemulsification.

PURPOSE: To compare long-term postoperative refractive outcomes between phacotrabeculectomy and phacoemulsification, both with posterior chamber intraocular lens implantation. SETTING: Department of Ophthalmology, Konyang University, Kim's Eye Hospital, Myung-Gok Eye Research Institute, Seoul, South Korea. DESIGN: Retrospective comparative study. METHODS: Postoperative refractive outcomes were compared between patients with cataract and coexisting primary or secondary open-angle glaucoma (OAG) who had phacotrabeculectomy (combined group) and patients with cataract with or without coexisting OAG who had phacoemulsification alone (phaco-only group). The refractive prediction error, mean absolute error, and median absolute error were compared between groups. Subgroup analysis based on preoperative axial length (AL) was performed (medium >22.0 to <24.5 mm; medium-long ≥24.5 to <26.0 mm; long ≥26.0 mm). RESULTS: The combined group comprised 51 eyes and the phaco-only group, 74 eyes. The mean interval between surgery and refraction measurement was 14.70 months ± 10.80 (SD) (median 13.0 months) and 4.81 ± 4.97 months (median 2.0 months), respectively. Postoperatively, there was no statistically significant between-group difference in the following mean values: refractive prediction error, -0.05 ± 0.64 versus -0.04 ± 0.52 (P = .905); mean absolute error, 0.46 ± 0.44 versus 0.38 ± 0.36 (P = .258); median absolute error, 0.32 (interquartile range [IQR], 0.17, 0.67) versus 0.28 (IQR, 0.13, 0.54) (P = .297). Subgroup analysis also did not show significant differences between the 2 groups (all P > .05). CONCLUSION: The long-term postoperative refractive outcomes of phacotrabeculectomy and phacoemulsification alone were not significantly different in eyes with OAG, regardless of preoperative AL.

The immunogenicity and protection effect of an inactivated coxsackievirus A6, A10, and A16 vaccine against hand, foot, and mouth disease.

Coxsackievirus belongs to the Enterovirus genus of the Picornaviridae family and is one of the major pathogens associated with human hand, foot, and mouth disease (HFMD). Historically, outbreaks of HFMD have mainly been caused by enterovirus 71 and coxsackievirus A16. Recently, coxsackieviruses A6 and A10 have been associated with increased occurrences of sporadic HFMD cases and outbreak events globally. In this study, the immunogenicity of coxsackieviruses A6, A10, and A16 (CA6, CA10, and CA16), which were inactivated by formalin or ß-propiolactone (BPL) under different conditions, was evaluated as multivalent vaccine candidates. CA6 induced similar immune responses with both inactivation methods, and the immune efficacy of CA10 and CA16 was better following inactivation with BPL than with formalin. There was no sufficient cross-reactivity or cross-protectivity against heterologous strains in groups vaccinated with the BPL-inactivated (BI) monovalent vaccine. Sufficient neutralizing antibody and cell-mediated immune responses were induced in the BI-trivalent vaccinated group. These findings suggest that BI-CA6, CA10, and CA16 are potential multivalent vaccine candidates and that a multivalent vaccine is needed to control HFMD. The coxsackievirus multivalent vaccine could be useful for the development of effective HFMD vaccines.

Glaucomatous progression in the retinal nerve fibre and retinal ganglion cell-inner plexiform layers determined using optical coherence tomography-guided progression analysis.

BACKGROUND: To investigate the characteristics of glaucomatous progression in circumpapillary retinal nerve fibre layer (RNFL) and macular retinal ganglion cell-inner plexiform layer (GCIPL) determined using optical coherence tomography-guided progression analysis (OCT-GPA). METHODS: Serial OCT images of 527 glaucomatous eyes with greater than four OCT tests were screened. Among them, 106 (20.1 per cent) eyes with progression in either RNFL or GCIPL determined using OCT-GPA were included. Based on the agreement of progression detection between RNFL and GCIPL, the eyes were classified into the 'RNFL progression earlier group', 'GCIPL progression earlier group', or 'simultaneous progression group'. The type of progression was classified as diffuse, localised or mixed. RESULTS: Among the 106 eyes with progression, 100 (94.3 per cent) showed RNFL progression and 83 (78.3 per cent) showed GCIPL progression. Fifty-four (50.9 per cent), 13 (12.3 per cent), and 39 (36.8 per cent) eyes were classified into the RNFL progression earlier group, GCIPL progression earlier group, and simultaneous progression group, respectively. Diffuse-type progression was found in three (three per cent) eyes with RNFL progression and 32 (38.6 per cent) eyes with GCIPL progression. The most common location of progression was the 7 o'clock sector (42.0 per cent) in the RNFL and the inferotemporal sector (39.8 per cent) in the GCIPL. CONCLUSIONS: The most common characteristic of RNFL and GCIPL progression determined using OCT-GPA was localised thinning in the inferotemporal area. Progression was more frequently found in the RNFL than in the GCIPL, and diffuse-type progression was more frequent in the GCIPL than in the RNFL.