Kumamoto, Aug 28, 2024 (News On Japan) - As Kumamoto Prefecture battles an outbreak of norovirus among people who played in the waters at ‘Todoroki Falls’ in Amakusa City, water quality tests have uncovered the virus in the surrounding area.
Kumamoto Prefecture's Health Crisis Management Division Chief Kunihiko Yumigake stated, "Norovirus G2 was detected in two locations: the basin of the falls and just above the waterfall."
Norovirus, often found in shellfish like oysters and notorious for causing food poisoning, especially in winter, was also detected in six of the sixteen patients tested.
However...
Chief Yumigake further explained, "The G2 norovirus found in stool samples matched the administrative test results, but the genetic type differed from the G2 norovirus detected in the river water."
The prefecture has tested the genetic types of the norovirus found in four individuals so far. Among these four, some belonged to different groups and visited the river on different days. Despite this, it remains unclear if the river was the source of the infection, as the genetic type of the norovirus in the river water does not match that found in the patients.
Chief Yumigake added, "While norovirus has been detected in both the river water and stool samples, we have not yet reached a definitive conclusion on the link to this incident."
This raises further questions about the possibility of a mass norovirus infection originating from river water.
The prefecture noted that norovirus is present in nature, and infections could potentially occur in stagnant water areas. However, infectious disease expert Professor Tetsuya Matsumoto of the International University of Health and Welfare offered a different perspective.
"It's entirely unexpected. It's highly unusual for so many cases of norovirus infection to occur in a natural setting," Professor Matsumoto pointed out, suggesting the possibility that a person might have been the source of the virus.
"If someone infected with norovirus were to release a significant amount of the virus through vomiting or defecation, it could contaminate the surroundings and lead to further infections," Professor Matsumoto explained.
Kumamoto Prefecture plans to continue investigating the water quality and will also inspect nearby toilets and other potential sources as they work to determine the cause of the health issues.
Source: ANN
