Effect of the continuous intake of probiotic-fermented milk containing Lactobacillus casei strain Shirota on fever in a mass outbreak of norovirus gastroenteritis and the faecal microflora in a health service facility for the aged

Abstract

For conducting effective risk management in long-stay elderly people at a health service facility, we performed an open case-controlled study to evaluate the effect of the intake of probiotic-fermented milk containing Lactobacillus casei strain Shirota (LcS-fermented milk) on norovirus gastroenteritis occurring in the winter season during the intake period. A total of seventy-seven elderly people (mean age 84 years) were enrolled in the study. During a 1-month period, there was no significant difference in the incidence of norovirus gastroenteritis between the LcS-fermented milk-administered (n 39) and the non-administered (n 38) groups; however, the mean duration of fever of .378C after the onset of gastroenteritis was 1·5 (SD 1·7) d in the former and 2·9 (SD 2·3) d in the latter group, showing a significant shortening in the former group (P, 0·05). RT-quantitative PCR analysis targeting ribosomal RNA showed both Bifidobacterium and Lactobacillus to be significantly dominant, whereas Enterobacteriaceae decreased in faecal samples from the administered group (n 10, mean age 83 years), with a significant increase in faecal acetic acid concentration. Continuous intake of LcS-fermented milk could positively contribute to the alleviation of fever caused by norovirus gastroenteritis by correcting the imbalance of the intestinal microflora peculiar to the elderly, although such consumption could not protect them from the disease.

Norovirus

“…Norovirus nucleic acid was detected in 34.2% of stool samples from lactoferrin recipients and in 35.5% of stool samples from placebo recipients. The prophylactic administration of "probiotic fermented" milk containing a strain of Lactobacillus casei failed to prevent norovirus infection in elderly residents of a health service facility in Japan (92).…”

Norovirus vaccines: Correlates of protection, challenges and limitations

“…24 The prophylactic administration of bovine lactoferrin or probiotic fermented milk failed at preventing NoV infection in children and elderly residents of a health care facility, respectively. 25,26 The development of an effective treatment for NoV infections among children and immunosuppressed patients is needed to reduce the burden of gastroenteritis.…”

Impact of high fat diets, prebiotics and probiotics on gut microbiota and immune function, with relevance to elderly populations

“…( Table 1). Daily administration of L. casei has been observed to reduce numbers of Enterobacteriaceae, some of which are pathogenic [74]. Different L. casei strains have varying functions and health benefits.…”