From the Guidelines
Vivotif is recommended for travelers to regions where typhoid fever is common, particularly South Asia, Southeast Asia, Africa, and parts of South America, as an adjunct to hand hygiene and the avoidance of high-risk foods and beverages, based on the strongest and most recent evidence from 2017 1. The standard regimen consists of four capsules taken over 7 days, with one capsule taken every other day, as supported by studies from 1990 1. Each capsule should be swallowed whole (not chewed) with cold or lukewarm water at least one hour before meals. The vaccine contains live attenuated bacteria and should be refrigerated until use. Some key points to consider when using Vivotif include:
- Protection begins about 7-10 days after completing the series and lasts approximately 5-7 years, as indicated by studies from 1991 1 and 1990 1.
- It's not suitable for everyone - those with weakened immune systems, active gastrointestinal illness, or antibiotic treatment should avoid it.
- Side effects are generally mild and may include stomach discomfort, nausea, headache, or fever.
- The vaccine works by stimulating the immune system to produce antibodies against typhoid bacteria, providing protection when exposed to the actual pathogen. It is essential to follow the recommended guidelines and consult with a healthcare professional before administering Vivotif, especially for individuals with specific health conditions or concerns.
From the FDA Drug Label
Vivotif (Typhoid Vaccine Live Oral Ty21a) is indicated for immunization of adults and children greater than 6 years of age against disease caused by Salmonella typhi. The Vivotif vaccine is used for immunization against typhoid fever in individuals 6 years of age and older.
- It is recommended for:
- Travelers to areas with a recognized risk of S. typhi exposure
- Persons with intimate exposure to a S. typhi carrier
- Microbiology laboratorians who frequently work with S. typhi 2
- The vaccine is not suitable for treatment of acute infections with S. typhi.
- Vaccinated individuals should continue to take personal precautions against exposure to typhoid organisms.
From the Research
Vivotif Overview
- Vivotif is an oral typhoid vaccine, also known as Ty21a, used to protect against typhoid fever.
- The vaccine is made from a weakened form of the Salmonella Typhi bacteria and is given in capsule form.
Efficacy of Vivotif
- Studies have shown that Vivotif is effective in preventing typhoid fever, with efficacy rates ranging from 35% to 58% in the first two years after vaccination 3.
- The vaccine's efficacy decreases over time, with no benefit detected in the third year after vaccination 3.
- A study comparing Vivotif to the Vi polysaccharide vaccine found that Vivotif prevents around one-third to one-half of typhoid cases in the first two years after vaccination, while the Vi polysaccharide vaccine prevents around two-thirds of typhoid cases in the first year after vaccination 4.
Safety and Tolerability of Vivotif
- Vivotif is generally well-tolerated, with few side effects reported, including vomiting, diarrhea, nausea, abdominal pain, headache, and rash 3, 4.
- Fever is more common in the vaccine group compared to the placebo group 3, 4.
Comparison to Other Typhoid Vaccines
- Vivotif has been compared to the Vi polysaccharide vaccine in several studies, with both vaccines showing similar efficacy rates 4, 5.
- A study found that concomitant administration of Vivotif and the Vi polysaccharide vaccine induces an additive immune response, enhancing the magnitude of both typhoid-specific plasmablast responses and those cross-reacting with paratyphoid and non-typhoidal Salmonella serotypes 6.