Impact of Infectious Disease after Lactococcus lactis Strain Plasma Intake in Vietnamese Schoolchildren: A Randomized, Placebo-Controlled, Double-Blind Study.

Nghiem Nguyet Thu,Yuta Watanabe,Phung Thi Hau,Nguyen Lien Hanh,Ha Huy Tue,Nguyen Anh Tuan,Bui Thi Huong Lan,Truong Viet Dung,Osamu Kanauchi,Ryohei Tsuji,Nguyen Huu Hoan,Tran Thị Thu Trang,Naoki Yamamoto,Truong Tuyet Mai,Tran Chau Quyen

doi:10.3390/nu14030552

Abstract

Lactococcus lactis strain Plasma (LC-Plasma) is reported to have anti-viral effects via direct activation of plasmacytoid dendritic cells, which upregulate the production of type I and III interferons. A randomized, placebo-controlled, double-blind, parallel group study was designed for elementary schoolchildren, grades 1 to 3, in Vietnam. LC-Plasma or a control were administered to schoolchildren as a beverage (1.0 × 1011 count LC-Plasma/day/person). The primary endpoint was to determine the efficacy of LC-Plasma in reducing the cumulative days absent from school due to upper respiratory disease (URID) and gastrointestinal disease (GID), and the secondary endpoint was to evaluate the potency of LC-Plasma on URID/GID symptoms and general well-being scores. LC-Plasma intake significantly reduced the cumulative days absent from school due to URID/GID (Odds ratio (OR) = 0.57, p = 0.004) and URID alone (OR = 0.56, p = 0.005); LC-Plasma also significantly reduced the number of cumulative fever positive days during the first 4 weeks of intervention (OR = 0.58, p = 0.001) and cumulative days with diarrhea during the last 4 weeks of the intervention period (OR = 0.78, p = 0.01). The number of positive general wellbeing days was significantly improved in the LC-Plasma group compared with the control throughout the intervention period (OR = 0.93, 0.93, p = 0.03, 0.04 in the first and last 4 weeks of the intervention, respectively). These data suggest that LC-Plasma seems to improve the health condition of elementary schoolchildren and reduces school absenteeism due to infectious disease, especially URID.

Highlights

Changes in human ecology, such as global warming and an increased geographical movement of people and goods, have dramatically increased the risk of viral infection; the efficacy of vaccines and remedies for infectious diseases is limited by the high mutation rates of viruses [1]
It was reported to be very important to reduce the incidence of infectious disease in children in Vietnam, where these infectious disease are the major causes of morbidity and death in children [4]
It is well known that the influenza virus, rhinovirus, and respiratory syncytial virus play a major role in upper respiratory disease (URID) and it is generally acknowledged that the main prophylactic measures against these infectious diseases are vaccinations and everyday hygienic behaviors, such as gargling and hand-washing

Summary

Introduction

Changes in human ecology, such as global warming and an increased geographical movement of people and goods, have dramatically increased the risk of viral infection; the efficacy of vaccines and remedies for infectious diseases is limited by the high mutation rates of viruses [1]. Influenza is a malady of the human respiratory system, which causes economic and social burdens on society, especially among children and the elderly. The cost of children under 14 years old with influenza-like illness (ILI) was reported to be about 140 USD/episode and this burden is a serious issue in Vietnam [2]. In 2018, an ILI sentinel surveillance in northern Vietnam reported that 13.4% of ILI patients were influenza virus positive and the dominant pathogens were A/H3N2 and B [3]. It was reported that the highest morbidity rate was observed from June to September. Thi et al reported that the highest proportion of influenza was in the 5-to-14 age group during 2006 to 2013 surveillance in Vietnam [4]

Methods

Results

Conclusion