Vivotif

Typhoid Vaccine (Salmonella typhi)

Background information:

• most prevalent in impoverished areas with poor sanitation (usually Africa & Asia)
• humans are only reservoir
• more common in children and young adults
• 200-300 cases in US per year (80% due to travel)
• onset within 5-21 days of ingestion
• clinical presentation:
• week 1: fever, bacteremia
• week 2: abdominal pain, rose spots on trunk and abdomen
• week 3:hepatosplenomegaly, intestinal bleeding, perforation, peritonitis
• may cause septic shock
• gradually resolves over weeks-months
• lab findings: anemia, leukopenia (more common in adults), leukocytosis (more common in children, if seen in adults --> sign of intestinal perforation), abnormal LFT's

Vivotif - live enteric coated capsule vaccine

Mechanism of action: S. typhi penetrate intestinal mucosa and enter systemic circulation through the lymphatic system. Live vaccine causes cell autolysis before strain becomes virulent due to lack of enzyme, UDP-4 galactose epimerase

Administration:

Primary immunization: 1 capsule on days 1,3,5,7 (total of 4 doses)

*must complete at least 1 week prior to potential exposure

Re-immunization: repeat full course every 5 years

Approved for > 6 years and older

(Oral)

Swallow capsule whole after placing into mouth, do not chew or open

Take with cold/lukewarm beverage

Take 1 hour prior to meal

Avoid alcohol 1 hour before or 2 hours after adminstration (alcohol may disrupt enteric coating)

Not for routine vaccination

Limit to: travelers to areas with recognized risk, person with intimate exposure to household contact with S. typhi fever or known carrier, lab technicians with frequent exposure to S. typhi

*carrier = excretion of organism in stool or urine > 12 months after acute infection

Adverse effects: headache, skin rash, abdominal pain, nausea, fever, diarrhea

Contraindications: hypersensitivity to any ingredient in vaccine, congenital or acquired immunodeficiency (live vaccine), acute febrile illness

Should not be used to TREAT typhoid fever or chronic typhoid carriers

Not all will be completely protected by vaccine -- travelers should still take precautions to avoid contact or ingestion of potentially contaminated food or water

Drug interactions:

• effect may be reduced by some antibiotics (postpone vaccine until 3 days after cessation of antibiotic)
• immunosuppressants (methotrexate, mercaptopurine, leflunomide, etc.) 
• TB skin test -- live vaccine may diminish effect of skin test, postpone skin test 4-6 weeks apart from administration of live vaccine

Pregnancy: C, delay until 2nd or 3rd trimester if possible

Cost: $106.02

References:

Vivotif (typhoid vaccine) [prescribing information]. Redwood City, CA: PaxVax Inc.; September 2016

http://www.cdc.gov/vaccines/hcp/vis/vis-statements/typhoid.html. Last reviewed: 18 October 2016.