Jay S. Keystone

Definition of VFR

A traveler categorized as a VFR is an immigrant, ethnically and racially distinct from the majority population of the country of residence (a higher-income country), who returns to his or her homeland (lower-income country) to visit friends or relatives. Included in the VFR category are family members such as the spouse or children, who were born in the country of residence.

VFRs: An Important Category of Travelers

VFRs are increasing in numbers and importance with regard to travel health, as they represent a group whose morbidity is greater than other travelers.

• Altered migration patterns to North America over the past 30 years have resulted in many immigrants originating from Asia and Latin America instead of Europe.
• Although 12% of the U.S. population is foreign born, in 2007, 38% of those from the United States traveling overseas listed VFR as a reason for travel.
• VFRs experience a higher incidence of travel-related infectious diseases, such as malaria, typhoid fever, tuberculosis, hepatitis A, and sexually transmitted infections than other groups of international travelers.

Disproportionate Infectious Disease Risks in VFRs

There are a number of reasons for an increased risk of infectious diseases in the VFR population:

• Lack of awareness of risk
• 30% or fewer have a pre-travel health-care encounter
• Financial barriers to pre-travel health care
• Clinics are not geographically convenient
• Cultural and language barriers with health-care providers
• Lack of trust in the medical system
• May experience greater last-minute travel plans and longer trips
• Travel to higher-risk destinations, such as staying in homes and living the local lifestyle, which often includes lack of food and water precautions, bed nets, etc.
• Belief that they are “immune.” VFR health beliefs likely contribute to lower rates of vaccination against hepatitis A and typhoid and infrequent use of malaria chemoprophylaxis compared with other international travelers.

Malaria

• In 2006, >50% of imported malaria cases in U.S. civilians occurred among VFRs.
• Data from GeoSentinel, the International Society of Travel Medicine and CDC sentinel surveillance network, show VFRs are eight times more likely to acquire malaria than are tourist travelers. Reports from the United Kingdom have shown that VFR travelers to West Africa were 10 times more likely to develop malaria than were tourists.
• Many VFRs assume they are “immune”; however, in most VFRs, especially those who left their countries of origin years previously, immunity has waned and is no longer protective.

Other Infections

• In the United States, >75% of typhoid cases occur in VFRs, mostly from South Asia and Latin America; 90% of paratyphoid A cases are imported from South Asia as well.
• VFR children <15 years of age are at highest risk of hepatitis A, and many are symptomatic. In a British study, most cases were acquired in South Asia.
• Other diseases, such as tuberculosis, hepatitis A and B, cholera, and measles, occur more commonly in VFRs following travel.

Pre-Travel Health Counseling for VFRs

Table 8-8 summarizes VFR health risks and prevention recommendations. It is important to increase awareness among providers and the travelers themselves regarding the unique risks for travel-related infections and the barriers to travel health services. If possible, clinics should try to incorporate culturally sensitive educational materials and language translators, along with providing handouts in multiple languages (see www.tropical.umn.edu/vfr).

Vaccinations

Travel immunization recommendations and requirements for VFRs are the same as those for U.S.-born travelers. It is crucial, however, to first try to establish whether the immigrant traveler has had “routine” immunizations (e.g., measles, tetanus, etc.) or has a history of the diseases. Adult travelers, in the absence of documentation of immunizations, may be considered to be non-immune, and appropriate vaccinations (or serologic studies to check for antibody status) should be provided. There are a few important caveats:

• Immunity to hepatitis A should not be assumed; many young adults and adolescents from developing countries are still susceptible. Pre-travel serologic testing for both hepatitis A and B may be worthwhile.
• Consider varicella immunization for immigrants from South and Southeast Asia and Latin America. These travelers may be more susceptible, because infection occurs at an older age compared with its occurrence in temperate regions. Also, adults with varicella disease have greater morbidity and mortality than do children.

Malaria Prevention

VFR travelers to endemic areas should not only be encouraged to take prophylactic medications, but also should be reminded of the benefits of barrier methods of prevention, such as bed nets and insect repellents, particularly for children (see the Protection Against Mosquitoes, Ticks, and Other Insects and Arthropods section in Chapter 2). Posters depicting malaria prevention techniques are available on the CDC malaria prevention website at www.cdc.gov/malaria/travel/index.htm.

• VFRs should be advised that drugs such as chloroquine, proguanil, and pyrimethamine are no longer effective in most areas, especially in sub-Saharan Africa. These medications are often readily available and inexpensive in their home countries, but are not efficacious.
• VFRs should also be encouraged to purchase their medications before traveling to ensure good drug quality. Studies in Africa and Southeast Asia show that one third to one half of antimalarial drugs purchased locally were counterfeit or substandard.

References

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