Objectives
Kudoa septempunctata is a marine myxosporean parasite implicated in seafood-borne acute gastroenteritis, predominantly associated with the consumption of raw olive flounder. This study aimed to characterize the molecular and genetic features of K. septempunctata-associated with foodborne outbreaks in the Republic of Korea from 2016 to 2024. Methods: We reviewed 415 suspected foodborne outbreaks reported through national surveillance between 2016 and 2024. Among these, 37 outbreaks with complete clinical, epidemiological, and laboratory data from 2020 to 2024—including K. septempunctata testing and genotyping—were analyzed in detail. Results: Diarrhea (88.8%) and vomiting (61.2%) were the most common symptoms. The detection rate of K. septempunctata was significantly higher in specimens collected ≤24 hours after raw fish consumption (69.8%) than in those collected > 24 hours after consumption (35.9%). Outbreak occurrence was higher during warmer months (May–October) than during other periods, although this difference was not statistically significant. All sequences obtained from patient specimens belonged to sequence type 3 (ST3) of K. septempunctata. Conclusion: Since 2020, the proportion of reported outbreaks associated with Kudoa has increased, indicating its continued public health relevance. The timing of specimen collection is a key determinant of K. septempunctata detection, as diagnostic yield declines significantly when specimens are collected more than 24 hours after exposure. These findings highlight the need for standardized rapid investigation protocols and an integrated surveillance system linking clinical data with seafood supply-chain information.

<sec><title>Objectives</title><p>Korea was an endemic area for lymphatic filariasis (LF), caused by the nematode parasite <italic>Brugia malayi</italic>, until the 1970s. The World Health Organization recognized Korea as LF-free in June 2008. However, it is necessary to confirm that patients that have had LF in the past still test negative, to prevent the re-emergence of LF in Korea.</p></sec><sec><title>Methods</title><p>We followed up a total of 83 patients who had been diagnosed with LF between 2002 and 2010 in endemic LF areas.</p></sec><sec><title>Results</title><p>Fifty-two of the 83 subjects were negative for LF, whereas 31 subjects had re-located to a different city or province, were dead, or were unaccounted for. Most subjects with negative test results still exhibited edema in the legs or the arms, and some complained of redness and swelling in the legs or ankle joints. However, we found that these symptoms were due to diseases other than LF.</p></sec><sec><title>Conclusion</title><p>In this follow-up study, we did not find any evidence indicating the potential re-emergence of LF in Korea.</p></sec>