Sasaki Tadahiro, Morita Ryo, Aoyama Ikuko, Baba Takashi, Goto Tetsushi, Kubota-Koketsu Ritsuko, Samune Yoshihiro, Nakayama Emi E, Shioda Tatsuo, Shirano Michinori
Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
Department of Infectious Diseases, Osaka City General Hospital, Osaka, 534-0021, Japan.
Trop Med Health. 2024 Aug 1;52(1):50. doi: 10.1186/s41182-024-00620-5.
The number of dengue cases has increased dramatically in recent years. In Latin America, the number of cases and deaths in 2023 was the highest ever recorded. We report on a patient who had been infected with dengue virus during his stay in Costa Rica in September 2023, and developed the disease after returning to Japan. Plasma obtained from the patient was used for diagnosis and dengue virus serotyping by real-time PCR. The nucleotide sequence of the envelope region of dengue virus was then determined by the direct sequencing method, and this sequence was used for phylogenetic analyses. The patient was found to be infected with dengue virus type 3 genotype III. The sequence from the present case was more homologous with sequences registered in Florida, USA, associated with travel to Cuba in 2022 than with sequences registered in Costa Rica 10 years ago. The Pan American Health Organization reported that only dengue virus type 1 and 2 cases were reported in Costa Rica in 2019-2021, whereas dengue virus type 3 and 4 cases started being reported in 2022. In 2023, the reported numbers of cases with dengue virus types 3 and 4 exceeded those of dengue virus types 1 and 2. In addition, regional differences in endemic strains have been observed in Costa Rica. Our findings suggest that the dengue virus type 3 that infected the patient was more likely an influx of a strain that had been circulating in Caribbean countries such as Cuba in recent years, rather than a re-emergence of an indigenous virus in Costa Rica. The serotypes of dengue virus prevalent in Costa Rica have been changing since 2022. All four serotypes were prevalent in 2023, with a particularly sharp increase in the number of cases of dengue virus types 3 and 4. Future monitoring and surveillance are essential because changes in endemic serotypes can cause antibody-dependent enhancement, which can lead to severe dengue disease presentations.
近年来，登革热病例数急剧增加。在拉丁美洲，2023年的病例数和死亡数是有记录以来最高的。我们报告了一名患者，他于2023年9月在哥斯达黎加逗留期间感染了登革热病毒，并在返回日本后发病。从患者身上获取的血浆用于通过实时PCR进行诊断和登革热病毒血清分型。然后通过直接测序法确定登革热病毒包膜区域的核苷酸序列，并将该序列用于系统发育分析。发现该患者感染了3型登革热病毒基因型III。与10年前在哥斯达黎加登记的序列相比，本病例的序列与2022年在美国佛罗里达州登记的、与前往古巴旅行相关的序列更为同源。泛美卫生组织报告称，2019 - 2021年哥斯达黎加仅报告了1型和2型登革热病毒病例，而2022年开始报告3型和4型登革热病毒病例。2023年，报告的3型和4型登革热病毒病例数超过了1型和2型。此外，在哥斯达黎加观察到了地方流行毒株的区域差异。我们的研究结果表明，感染该患者的3型登革热病毒更有可能是近年来在古巴等加勒比国家流行的毒株的流入，而不是哥斯达黎加本土病毒的重新出现。自2022年以来，哥斯达黎加流行的登革热病毒血清型一直在变化。2023年所有四种血清型都很流行，3型和4型登革热病毒病例数尤其急剧增加。由于地方流行血清型的变化可能导致抗体依赖性增强，进而导致严重的登革热疾病表现，未来的监测至关重要。
