Safety of Lactobacillus Rhamnosus GG Vs. Placebo in Elderly Subjects Receiving Trivalent Inactivated Influenza Vaccine

Inclusion Criteria:

1. Age 65-80 years

2. Willing to complete the informed consent process

3. Able and willing to participate for the planned duration of the study, including
availability for follow-up telephone contact

4. Is community dwelling for the past two years

5. Has received routine physical in the past two years

6. Has no new chronic conditions in the past two years

7. Identifies a primary care clinician

8. Has received recommended preventive services (Task Force for Clinical Preventive
Services) for vaccination and cancer prevention/detection, e.g.:

1. Pneumococcal vaccination

2. Mammography

3. Screening colonoscopy for cancer

9. Willing to comply with protocol and report on compliance and side effects during the
study period

10. Informed consent obtained and signed prior to screening

Exclusion Criteria:

1. Self-reported vaccination with influenza vaccine for the current season

2. Vaccination with any vaccine within the one month period prior to study enrollment or
intent to receive any other vaccine during the study period

3. History of hypersensitivity to any influenza vaccine components including thimerosal
or egg

4. History of Guillain-Barre syndrome

5. History of avoidance of egg and/or egg based products for any reason

6. Acute febrile illness within the week prior to immunization - immunization deferred
until illness resolved

7. Consumption of supplements or food products containing LGG or probiotics for 28 days
prior to the start of the study or consumption of yogurt that has the "live and
active cultures" seal

8. Known or suspected allergies to probiotics, Lactobacillus, microcrystalline
cellulose, gelatin, or antibiotics that may be used to treat LGG bacteremia or
infection

9. Received oral or parenteral antibiotics within 4 weeks of enrollment or prescribed
antibiotics on the day of enrollment

10. Drug or alcohol abuse within the previous 12 months

11. Hospitalization, major surgery or endoscopy within the last 3 months

12. Scheduled hospital admission within 3 months of enrollment

13. Resident of a nursing home or rehabilitation center

14. Presence of any of the following:

1. Grade 2 or higher abnormal vital signs or abnormalities on physical exam

2. Indwelling catheter or implanted hardware/prosthetic device or feeding tube

3. Current or within the last 2 years, any episode of bowel leak, acute abdomen,
diverticulitis, bloody bowel movements or peptic ulcer disease, including any
surgical procedure or current prescription medications for any of these
conditions

4. Current or within the last 4 weeks, active bowel disease such as an episode of
infectious or non-infectious diarrhea, constipation or vomiting lasting more
than 12 hours or current prescription medications for any of these conditions

5. Any history of gastric or intestinal dysmotility, slowed transit time, variable
small intestinal permeability, pancreatitis, history of disease or current
prescription medication for any of these conditions

6. Any history of Hepatitis B or Hepatitis C infections, cirrhosis, or chronic
liver disease

7. Underlying structural heart disease such as abnormal native heart valve
replacement, Stage IV congestive heart failure

8. History of peripheral vascular disease or stroke

9. Immunosuppression including HIV positive, solid organ or stem cell transplant
recipient, receiving any oral or parenteral immunosuppressive therapy,
neutrophil count <500/mm^3, or an anticipated drop in the neutrophil count to
<500/mm^3 or active or planned chemotherapy or radiotherapy

10. History of collagen vascular or autoimmune disease

11. End stage renal disease

12. History of chronic obstructive pulmonary disease or asthma

13. Diabetes or thyroid disease

14. Active tuberculosis (TB), defined as undergoing a work up for suspected active
TB infection or currently on treatment for active TB

15. Positive drug or alcohol testing at screening or positive breathalyzer at baseline or
an unwillingness to undergo drug and alcohol testing

16. Abnormal laboratory tests defined as any of the following:

1. White blood cell (WBC) <3.3 or > 12.0 K/microliter

2. Platelets < 125 K/microliter

3. Hemoglobin Males: < 12.0 g/dL; Females < 11.0 g/dL

4. Creatinine > 1.8 mg/dL

5. Blood Urea Nitrogen (BUN)> 27 mg/dL

6. Aspartate aminotransferase (AST) > 1.25 ULN

7. Alanine aminotransferase > 1.25 ULN

8. Alkaline phosphatase > 2.0 ULN

9. Bilirubin (total) > 1.5 ULN

10. Glucose (nonfasting) > 126 mg/dL

11. Positive HIV, Hepatitis B surface antigen or Hepatitis C antibody

17. Any other condition that in the opinion of the investigator would jeopardize the
safety or rights of the subject participating in the study or would make it unlikely
the subject could complete the study