PHWR Public Health Weekly Report

Objectives: This study investigated the distribution of HIV-1 subtypes and patterns of antiretroviral drug resistance among newly diagnosed people with HIV in the Republic of Korea (ROK) from 2024 to 2025.
Methods: Samples were obtained from newly diagnosed antiretroviral therapy-naive individuals based on nucleic acid testing and serological assays. The nucleic acids were extracted, and polymerase chain reaction was performed to amplify the gag and pol genes, followed by Sanger sequencing. Genotyping and resistance profiles were determined using HIV BLAST (Los Alamos HIV Database) and Stanford University HIV Drug Resistance Database.
Results: Among 219 samples analyzed, subtype B accounted for 51.6%, while circulating recombinant forms (CRFs) accounted for 44.4%. Annual analysis showed that the proportion of subtype B decreased from 57.6% to 47.8%, whereas CRFs increased from 36.5% to 49.3%. Drug resistance analysis was performed on 212 samples. The prevalence of resistance to at least one antiretroviral drug decreased from 10.7% to 9.9%. By drug class, resistance to protease inhibitors increased from 2.5% to 5.6%, whereas resistance to integrase strand transfer inhibitors (INSTIs) decreased from 2.8% to 0.0%. Resistance associated with dolutegravir, recommended for monitoring by the World Health Organization, was detected in one case in 2024 and was not detected in 2025.
Conclusions: Subtype B remains predominant in the ROK, and CRFs constitute a substantial proportion, indicating considerable genetic diversity. These findings suggest increasing complexity of the epidemic, potentially associated with international mobility and interpopulation contact. Despite variation across drug classes, the absence of INSTI resistance supports the continued effectiveness of currently prescribed antiretroviral combination regimens. Continuous molecular surveillance and drug resistance monitoring are essential.

Objectives: This study aimed to identify limitations in interministerial role allocation and information sharing during the response to the 2025 Brucella canis outbreaks. It also sought to propose practical improvements for the One Health collaboration system through simulation exercises using the joint risk assessment (JRA) tool.
Methods: A tabletop exercise was conducted with 34 interministerial practitioners using scenarios based on actual B. canis cases and social issues in April and August 2025. The effectiveness of the exercise was evaluated using pre- and post-surveys (on a 5-point Likert scale) to assess changes in the participants’ understanding of risk assessment and perceptions of collaboration.
Results: Participants’ subjective understanding of risk assessment improved significantly, from an average score of 2.47 to 3.94 points. The “perception of the importance of interministerial collaboration” received the highest score (4.56 points). While participants gained experience in mediating conflicts between the social impact of pet-borne zoonoses and quarantine priorities, they reported a high cognitive burden during when formulating qualitative justifications for risk characterization.
Conclusions: An effective response to companion animal-derived zoonoses such as B. canis requires systems capable of reconciling interdepartmental differences in risk perception and supporting consensus-based decision-making. The findings suggest that the JRA tool, can serve as practical instruments for strengthening collaborative responses.