Chronological change in the incidence risk levels of mosquito-borne and rodent-borne infections
Year: 2025
Type: article
Abstract: Introduction: We examined the change over time in the incidence risk levels of mosquito-borne and rodent-borne infections. Methods: We used the data of “Summary of risk assessment of vector-borne disease at Japanese Quarantine ports and airports” described in the “Annual Report of Vector-borne Diseases Pathogens and Vector Surveillance” from 2019 to 2022 made by the Ministry of Health, Labour and Welfare. We compared the chronological changes from 2019 to 2022 in “the number of ports and airports in risk category A (very low due to ‘vector absence’)” [A] and “that in risk category B (low due to ‘indigenous vector presence but no pathogens’)” [B] of quarantinable infectious diseases evaluated by basic inspection, for dengue fever, Japanese encephalitis, West Nile fever and malaria, which are mosquito-borne infections, and plague, hemorrhagic fever with renal syndrome, Lassa fever, and South American hemorrhagic fever, which are rodent-borne infections, using a chi-square test. Results: For dengue fever, B significantly increased over time compared with A (A = 69 and B = 53 in 2019, A = 31 and B = 83 in 2020, A = 29 and B = 89 in 2021, and A = 26 and B = 95 in 2022; p<0.001). Similarly, for Japanese encephalitis, West Nile fever, and malaria, B significantly increased over time compared to A (p<0.001, p<0.001, and p=0.02, respectively). For plague, the chronological changes in A were not significantly different from those in B (A = 40 and B = 82 in 2019, A = 39 and B = 69 in 2020, A = 46 and B = 64 in 2021, and A = 42 and B = 65 in 2022: p=0.52). Similarly, for hemorrhagic fever with renal syndrome, Lassa fever, and South American hemorrhagic fever, the chronological changes in A were not significantly different from those in B (p=0.84, p=NA, and p=NA, respectively; NA: because there were no ports or airports in B from 2019 to 2022). Discussion: Global warming may extend the lifespan of indigenous vector mosquitoes, resulting in chronologically increased incidence risk levels of mosquito-borne infections. The extension of the lifespans of indigenous vector fleas and ticks due to global warming may offset the decrease in indigenous vector fleas and ticks due to a decrease in vector rodents. This decrease may be caused by a decrease in habitats due to the increase in sea level due to global warming. That offset may have resulted in no differences in the chronological changes between A and B. Conclusion: The incidence risk levels of mosquito-borne infections may have increased over time.
Authors: Dr Soichi Takeishi, Dr Tatsuo Inoue, Dr Koichi Miyamura
Language: English
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,900
OpenAlex ID: W4408046904