Study of the Effect of Probiotics on Respiratory Morbidity After Influenza Vaccination of Elderly in Nursing Homes

Universiteit Antwerpen

Status and phase

Completed

Phase 4

Conditions

Respiratory Tract Infections

Treatments

Drug: Lactobacillus casei Shirota

Study type

Interventional

Funder types

Other

Industry

Identifiers

NCT00849277

2414

Details and patient eligibility

About

The purpose of this study is to determine whether probiotic treatment improves the protection against respiratory infections after influenza vaccination in elderly living in nursing homes.

Full description

Influenza virus is a member of the orthomyxovirus family and causes an acute viral disease of the respiratory tract. The illness is usually self-limiting. Hospitalization and deaths mainly occur in high-risk groups (elderly, chronically ill). Response to vaccination is subject to high levels of variability due to age, stress, nutritional stage, etc.

Lactic acid bacteria are naturally commensal bacteria in the small and large intestines. These bacteria protect the host against potential pathogens by competitive exclusion and also by the production of antibacterial agents known as bacteriocins. It has only been recently shown that another mechanism whereby probiotic bacteria may provide a health benefit is by modulating immune responses.

Lactobacillus casei strain Shirota (LcS) is widely consumed in fermented milk products. Several studies, in animals as wells as in humans, report on the immunomodulatory functions of LcS.

The aim of this multicentre, randomized, placebo controlled, double blind study (RCT) is to assess if probiotic treatment with Lactobacillus casei Shirota improves the protection against influenza(-like) infections after vaccination with trivalent influenza vaccine in elderly residing in nursing homes.

Trial endpoints:

Clinical outcome: difference in incidence in upper respiratory tract infections (influenza-like illness)
Serological outcome: difference in influenza vaccine specific serum IgG between probiotic and control treatment

Enrollment

737 patients

Sex

All

Ages

65+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

healthy male and female volunteers of 65 years or older
volunteers reside in residential homes
volunteers must be willing to swallow Yakult/placebo 2x/day for 3 weeks prevaccination and 5 months follow-up
participants must be able to comply with requirements of study (e.g. assessment of respiratory symptoms, Yakult/placebo administration)
participants must read and sign written Informed Consent Form after the nature of the study has been fully explained

Exclusion criteria

elderly with:

any medical or practical condition which make the volunteer not suitable for participating in this study at discretion of the investigator
any current relevant infectious disease
any current known disorder having negative repercussions on the volunteer's immune system, such as auto-immune diseases, COPD requiring oxigen, cancer, chronic inflammatory disease
allergy to influenza vaccine, eggs, neomycin, amphotericin B, erythromycin, amantadine
ongoing treatment with immunosuppressive drugs, chemotherapeutics or other antineoplastic medication
current use of antibiotics or use 6 weeks prior to study entry
use of any investigative drug (other drugs who are also under investigation) within 90 days prior to study entry
with markedly abnormal results in any of the screening laboratory tests