What typhoid vaccine is recommended for a last-minute traveler to Costa Rica?

From the Guidelines

For a last-minute traveler to Costa Rica, the injectable typhoid vaccine Typhim Vi is the most practical recommended option, as it requires only one dose and can be administered at least 2 weeks before departure. The oral typhoid vaccine Vivotif (Ty21a) is also an option, but it consists of 4 capsules taken every other day, completed at least 1 week before travel, which may not be feasible for last-minute travel. Typhoid vaccination is recommended for travelers to Costa Rica who may consume higher-risk foods or beverages, especially those visiting rural areas or staying with locals, as stated in the guidelines by 1. The vaccines work by stimulating immunity against Salmonella Typhi bacteria, which cause typhoid fever. Protection lasts about 2-5 years depending on the vaccine type. In addition to vaccination, travelers should practice careful food and water precautions, as the vaccine is not 100% effective and doesn't protect against related infections like paratyphoid fever. According to 1, typhoid vaccination is indicated for travelers to areas with a recognized risk of exposure to S. typhi, which includes Costa Rica.

Some key points to consider:

• The risk of typhoid fever is greatest for travelers to developing countries, especially those who have prolonged exposure to potentially contaminated food and drink, as mentioned in 1.
• The vaccine is not a substitute for careful selection of food and drink, as it is not 100% effective, and the protection the vaccine offers can be overwhelmed by large inocula of S. typhi, as stated in 1.
• In general, live-virus vaccines should be avoided, but inactivated (killed) vaccines, such as the parenteral typhoid vaccine, can be used for persons at risk for exposure to typhoid fever, as recommended in 1 and 1.
• Travelers should be advised about other preventive measures appropriate for anticipated exposures, such as chemoprophylaxis for malaria, protection against arthropod vectors, and treatment with immune globulin, as mentioned in 1, 1, and 1.

Overall, the injectable typhoid vaccine Typhim Vi is a practical option for last-minute travelers to Costa Rica, and it is essential to practice careful food and water precautions to minimize the risk of typhoid fever.

From the FDA Drug Label

One dose of vaccine should be given at least 2 weeks prior to expected exposure Travelers should take all necessary precautions to avoid contact with or ingestion of contaminated food and water. Immunization (ingestion of all 4 doses of Vivotif (Typhoid Vaccine Live Oral Ty21a) should be completed at least 1 week prior to potential exposure to S. typhi.

For a last-minute traveler to Costa Rica, the Ty21a (PO) vaccine may not be the best option since it requires ingestion of 4 doses on alternate days and immunization should be completed at least 1 week prior to potential exposure. The Vi polysaccharide (IM) vaccine is given as a single dose, but it is recommended to be given at least 2 weeks prior to expected exposure. Given the time constraint, neither vaccine may be suitable for a last-minute traveler. It is essential for travelers to take all necessary precautions to avoid contact with or ingestion of contaminated food and water 2 3.

From the Research

Typhoid Vaccine Options for Last-Minute Travelers to Costa Rica

• The World Health Organization recommends the Vi tetanus toxoid (Vi-TT) conjugate vaccine, Typbar-TCV, as the preferred vaccine for all ages 4.
• For last-minute travelers, the Ty21a vaccine (oral vaccine, three doses) and the Vi polysaccharide vaccine (injection, one dose) are available options 4, 5, 6, 7.
• The Ty21a vaccine probably prevents around half of typhoid cases during the first three years after vaccination, while the Vi polysaccharide vaccine prevents around two-thirds of typhoid cases in the first year after vaccination 4.
• The Vi-rEPA vaccine (two doses) is another option, which prevents between 50% and 96% of typhoid cases during the first two years after vaccination 4, 6, 7.
• A new synthetic Vi polysaccharide vaccine, GelSite-OAc, is being developed, which has shown promising results in animal studies 8.

Efficacy and Safety of Typhoid Vaccines

• The licensed Ty21a and Vi polysaccharide vaccines are efficacious in adults and children older than two years in endemic countries 4, 6, 7.
• The Vi-rEPA vaccine is as efficacious as the licensed vaccines and may confer longer immunity 6, 7.
• The Ty21a vaccine is probably not associated with an increased risk of adverse events, while the Vi polysaccharide vaccine may cause local swelling and pain at the injection site 4, 6, 7.
• The Vi-rEPA vaccine has been shown to be safe and well-tolerated in clinical trials 6, 7.

Recommendations for Last-Minute Travelers

• Last-minute travelers to Costa Rica should consider getting vaccinated against typhoid fever, especially if they will be eating or drinking outside of major restaurants and hotels 5.
• The choice of vaccine depends on the individual's age, health status, and travel plans 4, 5, 6, 7.
• Travelers should consult with a healthcare professional to determine the best vaccine option for their specific needs 5.