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Acute infantile gastroenteritis caused by rotavirus in Japan
Abstract:
We had an outbreak of acute infantile gastroenteritis accompanied by milky-white stool (called Hakuri in Japanese) during the winters of 1976 and 1977. Stool specimens collected from 72 cases of Hakuri were studied by negative-staining electron microscopy. Rotavirus was detected with a very high frequency (89%). Rotavirus obtained from one of the patients was isolated and passaged in cultures of primary human embryonic kidney cells. Viral antigens could be detected in the cytoplasm of the cells by indirect immuno-fluorescence. The fluorescence-positive cells increased in number with repeated passage. Serum anti-viral activities in 11 patients were titrated by indirect immuno-fluorescence, using the cells infected with the passaged rotavirus. All 11 patients developed IgM responses in the convalescent phase. However, in 4 of the 11 patients, no IgG responses were detected even 2--3 weeks after the onset of illness. The reinfection which has occasionally be seen in our country may be related to these poor IgG responses.
Insights
Rotavirus caused a 1976-1977 outbreak of infantile gastroenteritis with milky stools. Most cases showed rotavirus, and some patients had poor IgG responses, potentially leading to reinfection.
Area of Science:
- Virology
- Pediatrics
- Immunology
Background:
- An outbreak of acute infantile gastroenteritis with milky-white stools (Hakuri) occurred in 1976-1977.
- This condition prompted an investigation into its causative agent and immunological response.
Purpose of the Study:
- To identify the pathogen responsible for the Hakuri outbreak.
- To investigate the immune response, specifically IgM and IgG, in affected infants.
Main Methods:
- Negative-staining electron microscopy was used on stool specimens from 72 cases.
- Rotavirus was isolated and passaged in human embryonic kidney cells.
- Indirect immunofluorescence was employed to detect viral antigens and titrate antiviral activity.
Main Results:
- Rotavirus was detected in 89% of the Hakuri cases.
- Viral antigens were confirmed in cell cultures via immunofluorescence, increasing with passage.
- All 11 patients studied showed IgM responses, but 4 had no detectable IgG response weeks after illness onset.
Conclusions:
- Rotavirus is a frequent cause of acute infantile gastroenteritis presenting with milky stools.
- Poor or absent IgG responses in some patients may predispose them to rotavirus reinfection.