HOME  •  HEALTH  •  LIBRARY  •  AREAS  •  CENTERS  •  BOARDS  •  CHATS  •  JOIN FREE

Travel/Vaccinations
MDAdvice.com Home > Health Topics > Informative Material >

Vaccine Recommendations for Travelers
Health-Care Provider Information

Date last rev'd: July 12, 1996

For questions on the normal, routine vaccination schedule for children less than 7 years of age refer to: Overall Immunization schedule (Childhood vaccines).

Primary Vaccination
Children 6 weeks through 6 years old (up to the seventh birthday)
One dose of DTP should be given IM on four occasions - the first three doses at 4 to 8 week intervals, beginning when the infant is approximately 6 weeks to 2 months old; customarily, doses of vaccine are given at 2, 4, and 6 months of age. Individual circumstances may warrant giving the first three doses at 6, 10, and 14 weeks of age to provide protection as early as possible, especially during pertussis outbreaks. The fourth dose is given approximately 6-12 months after the third dose to maintain adequate immunity during the preschool years. This dose is an integral part of the primary vaccinating course. DTP containing whole cell pertussis vaccine should be used for the first three doses. For the fourth dose, a product containing acellular pertussis vaccine (DTaP) may be used. If a contraindication to pertussis vaccination exists, DT should be substituted for DTP.

Children greater than or equal to 7 years of age and adults
For primary vaccination, a series of three doses of Td should be given IM; the second dose is given 4-8 weeks after the first, and the third dose 6-12 months after the second. Td rather than DT is the preparation of choice for vaccination of all persons greater than or equal to 7 years of age because side effects from higher doses of diphtheria toxoid are more common than they are among younger children.

Interruption of primary vaccination schedule
Interrupting the recommended schedule or delaying subsequent doses does not lead to a reduction in the level of immunity reached on completion of the primary series. Therefore, there is no need to restart a series if more than the recommended time between doses has elapsed.

Booster Vaccination
Children 4-6 years old (up to the seventh birthday)
Those who received all four primary vaccination doses before their fourth birthday should receive a fifth dose of either DTP or DTaP before entering kindergarten or elementary school. This booster dose is not necessary if the fourth dose in the primary series was given on or after the fourth birthday.

Children greater than or equal to 7 years of age and adults
Tetanus toxoid should be given with diphtheria toxoid as Td every 10 years. If a dose is given sooner as part of wound management, the next booster is not needed until 10 years thereafter. More frequent boosters are not indicated and can result in an increased occurrence and severity of adverse reactions. One means of ensuring that persons receive boosters every 10 years is to vaccinate them routinely at mid-decade ages, i.e., 15 years old, 25 years old, 35 years old, etc.

All travelers are strongly urged to be immune to measles. The protection of young adults who have escaped measles disease and have not been vaccinated is especially important. Consideration should be given to providing one dose of measles vaccine to persons born in or after 1957 who travel abroad who have not previously received two doses of measles vaccine and who do not have other evidence of measles immunity, unless there is a contraindication. In general, persons can be considered immune to measles if they 1) were born before 1957, 2) have documentation of physician-diagnosed measles, 3) have laboratory evidence of measles immunity, or 4) have proof of receipt of two doses of live measles vaccine on or after the first birthday.

The age at vaccination should be lowered for those children traveling to areas where measles is endemic or epidemic. Children 12-14 months of age may receive MMR before their departure, without need for an additional dose until school entry. Children 6-11 months of age should receive a dose of monovalent measles vaccine before departure, although MMR may be used if monovalent measles vaccine is not available. Children who receive monovalent measles vaccine or MMR before their first birthday must be revaccinated with two doses of MMR vaccine at later ages. Whereas the optimal age for the first revaccination is 15 months, the age for revaccination may be as low as 12 months if the child remains in a high-risk area. The second revaccination dose would normally be given when a child enters school or according to local policy.

Because virtually all infants less than 6 months of age will be protected by maternally derived antibodies, no additional protection against measles is necessary in this age group.

MUMPS
Mumps is still endemic throughout most of the world. While vaccination against mumps is not a requirement for entry into any country, susceptible children, adolescents, and adults would benefit by being vaccinated with a single dose of vaccine (usually as MMR), unless contraindicated, before beginning travel. Because of concern about inadequate seroconversion due to persisting maternal antibodies and because the risk of serious disease from mumps infection is relatively low, persons less than 12 months of age need not be given mumps vaccine before travel.

RUBELLA
Persons without evidence of rubella immunity who travel abroad should be vaccinated against rubella because rubella is endemic and even epidemic in many countries throughout the world. No immunization or record of immunization is required for entry into the United States. However, international travelers should have immunity to rubella (i.e., laboratory evidence of rubella antibodies or verified rubella vaccination on or after the first birthday). Protection is especially important for susceptible women of childbearing age, particularly those planning to remain out of the country for a prolonged period.

ACIP recommends that all children receive one of the conjugate vaccines licensed for infant use (HbOC or PRP-OMP), beginning routinely at 2 months of age. Administration of the vaccine series may be initiated as early as age 6 weeks.

If HbOC is to be used, previously unvaccinated infants 2-6 months of age should receive three doses given at least 2 months apart. Unvaccinated infants 7-11 months of age should receive two doses of HbOC, given at least 2 months apart, before they are 15 months old. Unvaccinated children 12-14 months of age should receive a single dose of vaccine before they are 15 months of age. An additional dose of HbOC should be given to all children at 15 months of age, or as soon as possible thereafter, at an interval not less than 2 months after the previous dose. The other two conjugate vaccines licensed for use at 15 months of age may be used for this dose, but there are no data demonstrating that a booster response will occur. An interval as short as 1 month between doses is acceptable but not optimal.

If PRP-OMP is to be used, previously unvaccinated infants 2-6 months of age should receive two doses 2 months apart and a booster dose at 12 months of age. Children 7-11 months of age not previously vaccinated should receive two doses 2 months apart and a booster dose at 15 months of age (or as soon as possible thereafter), not less than 2 months after the previous dose. Children 12-14 months of age not previously vaccinated should receive a single dose and a booster dose at 15 months of age (or as soon as possible thereafter), not less than 2 months after the previous dose. The other two conjugate vaccines licensed for use at 15 months of age may be used for this dose, but there are no data demonstrating that a booster response will occur. An interval as short as 1 month between doses is acceptable but not optimal.

Unvaccinated children 15-59 months of age may be given any one of the three conjugate vaccines licensed for this age group.

Ideally, the same conjugate vaccine should be used throughout the entire vaccination series. No data exist regarding the interchangeability of different conjugate vaccines with respect to safety, immunogenicity, or efficacy. However, situations will arise in which the vaccine provider does not know which type of Hib conjugate vaccine the child to be vaccinated had previously received. Under these circumstances, it is prudent for vaccine providers to ensure that at a minimum an infant 2-6 months of age receives a primary series of three doses of conjugate vaccine. These recommendations may change as data become available regarding the response to different conjugate vaccines in a primary series.

Hib Conjugate vaccines may be given simultaneously with diphtheria and tetanus toxoids and pertussis vaccine adsorbed (DTP); combined measles, mumps, rubella vaccine (MMR); oral poliovirus vaccine (OPV); or inactivated poliovirus vaccine (IPV). Any of the vaccines may be injected in the thigh, and two injections may be given in the same deltoid. All licensed conjugate vaccines should be administered by the intramuscular route. There are no known contraindications to simultaneous administration of any Hib conjugate vaccine with either pneumococcal or meningococcal vaccine.

Preexposure Prophylaxis
The major group for whom preexposure prophylaxis is recommended is international travelers. The risk of hepatitis A for United States (U.S.) citizens traveling abroad varies with living conditions, length of stay, and the incidence of hepatitis A virus (HAV) infection in areas visited. In general, travelers to northern and western Europe, Japan, Australia, New Zealand and North America (except Mexico) are at no greater risk of HAV infection than they would be in the U.S. Other areas of the world with intermediate or high rates of hepatitis A pose an increased risk for travelers. In developing countries, risk of HAV infection increases with duration of travel and is highest for those who live in or visit rural areas, trek in back country, or frequently eat or drink in settings of poor sanitation. Recent studies have shown that many cases of travelrelated hepatitis A occur in travelers with "standard" tourist itineraries, accommodations, and food and beverage consumption behaviors. In developing countries, travelers should minimize their exposure to hepatitis A and other enteric diseases by avoiding potentially contaminated water or food. Travelers should avoid drinking water (or beverages with ice) of unknown purity and eating uncooked shellfish or uncooked fruits or vegetables they did not peel or prepare.

Hepatitis A vaccine or immune globulin (IG) is recommended for all susceptible persons traveling to or working in countries with intermediate or high rates of HAV infection. Vaccination of children 2 years of age and older, adolescents and adults at the age-appropriate dose is preferred for those who plan to travel repeatedly or reside for long periods in intermediate or high risk areas. Immune globulin is recommended for travelers < 2 years of age. Immune globulin is recommended for persons 2 years of age and older who desire only short term protection.

Two hepatitis A vaccines are licensed for use in the United States, HAVRIX® (manufactured by SmithKline Beecham Biologicals), and VAQTA® (manufactured by Merck Co., Inc.). Both are inactivated vaccines. The vaccine should be administered by intramuscular injection into the deltoid muscle. It is licensed in adult and pediatric formulations, with different dosages and administration schedules. Travelers can be considered to be protected four weeks after receiving the initial vaccine dose. Persons who travel to intermediate or high risk areas less than 4 weeks after the initial dose of vaccine should also be given IG (0.02 ml/kg of body weight), but at a different injection site. The vaccine series must be completed for long-term protection. Estimates derived by modeling techniques suggest that vaccine may provide protective antibody against hepatitis A for at least 20 years.

For travelers who plan to use IG, a single dose of IG (0.02 ml/kg of body weight) is recommended if travel is for less than 3 months. For prolonged travel or residence in developing countries a higher dosage of IG should be used (0.06 ml/kg of body weight) and should be repeated every 5 months. Immune globulin produced in developing countries may not meet the standards for purity required in most developed countries. Persons needing repeat doses overseas should use products that meet U.S. license requirements.

Prevaccination Testing
Prevaccination testing is not indicated for children because of their expected low prevalence of prior HAV infection. For some adult travelers who are likely to have had hepatitis A in the past (i.e., persons older than 40 years of age, persons born in parts of the world with intermediate or high levels of hepatitis A, or persons with clotting disorders), screening for HAV antibodies before travel may be useful to determine susceptibility and eliminate unnecessary vaccination or IG prophylaxis. Factors to consider before doing prevaccination testing include: 1) the cost of vaccination compared with the cost of serologic testing, including the cost of an additional visit and 2) the likelihood that prevaccination testing will not interfere with completion of the vaccine series.

For additional information, read “Hepatitis A Vaccine and Immune Globulin (IG).”

Hepatitis B vaccine is a routine vaccination for infants and children under 2 years of age. All infants and children should be vaccinated. If a child reaches 11-12 years of age and has not received hepatitis B vaccine, vaccine should be given. For other age groups, vaccination should be considered for persons who plan to reside for more than 6 months in areas with high levels of endemic hepatitis B virus (HBV) infection (such as Southeast Asia, Africa, the Middle East, the islands of the South and Western Pacific, and the Amazon region of South America), and who will have close contact with the local population. Vaccination should also be considered for short term travelers who are likely to have contact with blood from or sexual contact with residents of areas with high levels of endemic disease. Ideally, hepatitis B vaccination of travelers should begin at least 6 months before travel to allow for completion of the full vaccine series. An alternative four-dose schedule may provide protection during travel if the first three doses can be delivered before travel.

Travelers to countries where poliomyelitis is epidemic or endemic are considered to be at increased risk of poliomyelitis and should be fully immunized. In general, travelers to developing countries should be considered to be at increased risk of exposure to wild poliovirus. A primary series consists of either three doses of trivalent oral polio vaccine (OPV) or enhanced potency inactivated polio vaccine (eIPV). Unvaccinated or partially vaccinated travelers should complete a primary series with the vaccine that is appropriate to their age and previous immunization status. Persons who have previously received a primary series may need additional doses of a polio vaccine before traveling to areas with an increased risk of exposure to wild poliovirus.

Children and Adolescents
Trivalent oral polio vaccine (OPV) is the vaccine of choice for all infants, children, and adolescents (up to 18th birthday) if there are no contraindications to vaccination with OPV. Inactivated polio vaccine (eIPV) also is available. Those who have not completed a primary series should do so. If time is a limiting factor, at least one dose of OPV or eIPV should be given. Those who have completed a primary series of OPV (or a primary series and a supplementary dose administered between 4 and 6 years of age) should be given, once, a single additional dose of OPV. Likewise, those who have completed a primary series of IPV (or a primary series and a supplementary dose administered between 4 and 6 years of age) should be given a dose of eIPV or OPV. The need for further supplementary doses of OPV or eIPV has not been established.

When time permits, children traveling to endemic areas should receive at least 3 doses of OPV at intervals of at least 6-8 weeks. Children who have received 3 prior doses of OPV should receive a fourth dose if at least 6 weeks have elapsed since the third dose. In the United States, the Advisory Committee on Immunization Practices (ACIP) recommends that a primary series of 3 doses of oral poliovirus vaccine (OPV) be given beginning preferably at 6 weeks of age and at intervals of at least 6 weeks (the third dose typically is given several months after the second). However, in polio endemic areas, the Expanded Programme on Immunization of the World Health Organization recommends that a dose of OPV be given in the newborn period, e.g., at birth or before 6 weeks of age, with 3 additional doses (the primary series) given subsequently at 6, 10, and 14 weeks of age. While ideally the ACIP recommendations on age and intervals between doses of OPV should be followed, if travel to an endemic country will occur before a child is 6 weeks of age, a dose of OPV should be given prior to travel. A dose of vaccine administered before 6 weeks of age should not be counted as part of the standard 3dose primary series. If the child remains in an endemic country, the child should receive the first dose of the standard 3dose primary series no sooner than 4 weeks after the newborn period dose and the remaining 2 doses of the primary series at 4week intervals. If the child has left the endemic area, the first dose of the primary series should be given 6 weeks after the newborn period dose, the second dose 6 weeks after the first dose and the third dose of the primary series 8-12 months after the second as is generally the practice in the United States.

Children traveling to an endemic country who have received a first or second dose of the primary series of OPV but lack sufficient time to complete the primary series schedule as generally practiced in the United States should receive their second and/or third doses of OPV 4 weeks after their prior dose(s). Children with less than a primary series at the time of departure to an endemic area and who remain in an endemic area should complete the 3dose primary series within the endemic area with doses at 4week intervals.

No data or recommendations are available for the use of eIPV prior to 6 weeks of age. Otherwise, a primary series of eIPV consists of 3 doses which can be given at the same intervals as are recommended for OPV.

Adults
Unvaccinated or unknown immunization status
For unvaccinated adults and adults whose immunization status is unknown who are traveling to countries in which the risk of exposure to wild polio virus is increased, primary immunization with eIPV is recommended whenever this is feasible. eIPV is preferred because the risk of vaccineassociated paralysis following OPV is slightly higher in adults than in children.

Three doses of eIPV should be given before departure using the normal schedule. In circumstances where time does not permit this to be done, the following alternatives are recommended:

1. If less than 3 months, but more than 2 months are available before protection is needed, 3 doses of eIPV should be given at least 4 weeks apart.
2. If less than 8, but more than 4 weeks are available before protection is needed, 2 doses of eIPV should be given at least 1 month apart.
3. If less than 4 weeks are available before protection is needed, a single dose of OPV or eIPV is recommended.

In both #2 and #3 above, the remaining doses of vaccine should be given later, at the recommended intervals, if the person remains at increased risk.

Previously received less than full primary series of OPV or any type IPV
Adults who are at increased risk of exposure to poliomyelitis and who have previously received less than a primary series of OPV and/or IPV should be given the remaining required doses with either OPV or eIPV vaccine, regardless of the interval since the last dose and of the type of vaccine previously received.

Previously received complete series with any one or combination polio vaccines
Adults who are at increased risk of exposure to poliomyelitis and who have previously completed a primary series with any one or combination of polio vaccines can be given, once, a dose of OPV or eIPV. The need for further doses of either vaccine has not been established.

Typhoid fever is an acute bacterial disease caused by Salmonella typhi. The onset of typhoid fever is normally gradual, with fever, malaise, chills, headache, and generalized aches in the muscles and joints. The spleen is usually enlarged, there is generally a decrease in the number of white blood cells, and small, discrete, rosecolored spots may appear on the trunk. Diarrhea is infrequent, and vomiting, which may occur toward the end of the first week, is not usually severe. Abdominal distention and tenderness are common. Diagnosis comes from isolation of Salmonella typhi from the blood or stool of an infected person.

Salmonella typhi is transmitted by contaminated food and water and is prevalent in many developing countries of Latin America, Africa, and Asia. It became rare in the United States and other industrialized countries with the development of protected water supplies, pasteurization of milk, and improved sewage systems. The best protection is to avoid consuming food or water that may be contaminated. Travelers to developing countries can lower their risk of infection by drinking only bottled or boiled beverages and eating only cooked food. In addition vaccines are available that afford significant protection.

Quinolones or third generation cephalosporins are the most effective drugs for treatment of acute typhoid fever when antibiotic sensitivities of the organism are not known. Trimethoprimsulfamethoxazole, ampicillin, amoxicillin, and chloramphenicol are effective alternatives for suspectable organisms.

Eliminating the bacteria from carriers is difficult. A 6week course of ampicillin with probenecid has been successful for treating chronic carriers with normal gallbladders and without evidence of gallstones. A prolonged course of amoxicillin has been reported to be effective even in patients with gallstones or nonfunctioning gallbladders. Other effective treatments include trimethoprimsulfamethoxazole and fluoroquinolones.

Removal of the gallbladder is also useful in eradicating the carrier state and may be necessary for patients whose illnesses relapse after therapy or who cannot tolerate antimicrobial therapy.

The incidence of typhoid fever in the United States fell from 1 case per 100,000 population in 1955 to 0.2 cases per 100,000 in 1966 and has since remained fairly stable. Between 1985 and 1994, 72% of cases in the United States were imported, in contrast to 33% between 1967 and 1972. The major sources of imported cases between 1985 and 1994 were people coming from Mexico and the Indian Subcontinent. The casefatality rate during this time was 0.5%.

Typhoid Vaccine

Currently available vaccines have been shown to protect 70% - 90% of recipients. Therefore, even vaccinated travelers should be cautious in selecting their food and water.

The oral vaccine consists of four capsules containing live attenuated bacteria. They are taken every other day for 7 days. The entire four doses should be repeated every 5 years if the person is at continued risk. Reactions are rare and include nausea, vomiting, abdominal cramps, and skin rash.

The new injectable ViCPS vaccine consists of 1 shots. A booster dose given every 2 years provides continued protection for repeated exposure. Reactions are rarer than with the old, killed injectable typhoid vaccine, and include discomfort at the site of injection for 1-2 days, fever, and headache.

Either of these vaccines may be given simultaneously with other vaccines.

Division of Quarantine
National Center for Infectious Diseases
Centers for Disease Control and Prevention
Atlanta, GA

 Home  |  Help  |  Feedback  |  Privacy Policy  |  Register  |  Contact Us  |  Visitor Survey  |  Subscribe to HealthMail  |  Advertising  |  About MDAdvice.com

Copyright © The Online Medical Network Inc. All rights reserved. All material provided by MDAdvice.com is intended for informative purposes only and is not a substitute for professional medical advice. Please consult your physician with any questions or concerns you may have regarding your health. Use of this site indicates your agreement with the Terms of Use.