Malaria Risk in Travelers Visiting Friends and Relatives
Between 1999 and 2008, 756 cases of malaria were reported in Florida
(mean=76). Nearly all reported malaria infections were imported and associated
with travel or immigration. Although malaria is no longer considered endemic to
Florida, it was a significant disease threat in the first half of the 20th
century prior to development of effective insecticides and organized mosquito
control, and competent vectors are still present throughout the state. A recent
outbreak in Palm Beach County in 2003 illustrated the potential for
re-introduction into the state. , For this reason it is important to identify
risk factors that are associated with infections acquired outside the country to
protect the health of both travelers and non-travelers.
Data from the 65 cases of malaria reported in 2008 provide a snapshot of typical
malaria patients in Florida: The majority of patients were diagnosed with
infections caused by malaria species having the most potential for a severe
outcome, Plasmodium falciparum (86%) and P. vivax (11%). Twenty-six cases (40%)
reported recent travel to Haiti, 18 (28%) reported travel to Nigeria, and
Uganda/Kenya and Ghana were each linked to four cases (6% each). The remaining
cases traveled to a variety of countries in Africa, South and Central America,
and Asia. Of those case reports that included reason for travel (39/65), the
largest proportion (49%) indicated travel was to visit friends or relatives (VFRs).
Those classified as VFRs are primarily immigrants from malaria-endemic
developing countries. They have a several-fold increased risk of infection
compared with tourists and other groups of travelers. This increased risk has
been attributed to high risk behaviors such as longer visit times and staying in
villages and remote rural areas without screened windows or air conditioning.
Additionally, VFRs are more likely to neglect personal protective measures
against mosquitoes, such as prophylactic drugs, insect repellents, and bed nets.
This may be because they believe themselves to be immune to the disease after
having lived in an endemic area in the past. However, any immunity they may have
had is lost over time, leaving them vulnerable to serious infections when they
return to their home country. Their children who were born in the U.S. have no
VFRs are also less likely than other travelers to seek pre-departure medical
advice. This may be associated with the cost of a physician visit. Insurance
rates in this population are low, and even for those who are insured, visits to
a travel medicine specialist and chemoprophylaxis are often not covered. Primary
care providers may not have the most up-to-date information about malaria
distribution and drug resistance. A Canadian study of VFRs traveling to India
showed that family practitioners were the primary source of information and that
only 31% of travelers planned to use prophylaxis, less than 10% intended to use
personal protective measures, and only 7% had been prescribed appropriate
prophylaxis for their destination. Some travelers also plan to buy prophylaxis
at their destination, but these may contain the wrong drug, an incorrect amount
of drug, or be contaminated.
Because of these risks, it is important to target messages to immigrant
populations that may plan trips to their home countries. Promotion of travel
medicine services as well as educational materials can be distributed through
appropriate-language pamphlets, posters, and other ethnic media and community
organizations such as churches. Primary care clinics that treat large numbers of
immigrants should be encouraged to provide travel medicine training to
practitioners to ensure they can provide high quality travel medicine services
in a familiar and accessible setting. The practitioner should review the
traveler's itinerary to provide specific guidelines and determine what type of
chemoprophylaxis, if any, is recommended based on anti-malarial resistance and
malaria risk in the area of travel. Convenience and low side effects are
important considerations to increase compliance. The traveler should also
understand the symptoms of malaria such as fever, chills, headache, muscle
aches, fatigue, nausea, jaundice, vomiting, and diarrhea, so that they can seek
medical attention if they become sick. In some cases, they can be prescribed
stand-by medication for use if symptoms appear.
Educational materials should include information about malaria and preventive
measures such as personal protection against mosquitoes and chemoprophylaxis.
Mosquito avoidance practices are similar to those employed in the United States:
staying inside with screened doors and windows during peak biting times from
dusk to dawn, wearing clothing that covers the skin, and using insecticides and
repellents, but should also include insecticide impregnated bed nets. These
measures also protect against other tropical mosquito-borne diseases, such as
dengue and Chikungunya, making the message even more important. The overall VFR
campaign could also include information on preventing other diseases that they
are at risk for, including food-borne diseases and tuberculosis.
Preventing Mosquito Bites
If possible, remain indoors in a screened or air-conditioned area during
the peak biting period between dusk and dawn.
If no screening or air conditioning is available, use
pyrethroid-containing repellent in living and sleeping areas during evening
and night-time hours and sleep under bed nets, preferably
insecticide-treated. For information on ordering insecticide-treated bed
www.travmed.com, phone 1-800-872-8633
www.travelhealthhelp.com, phone 1-888-621-3952
Wear long-sleeved shirts, long pants, and hats when outdoors.
Use insect repellent when outdoors. Sprays that contain DEET (N,N-diethyl-meta-toluamide)
offer good protection . Follow the directions on the product label.
Higher concentrations of DEET may have a longer repellent effect;
however, concentrations over 50% provide no added protection. Timed-release
DEET products may have a longer repellent effect than liquid products.
DEET should not be used on children younger than two months. Assist
children less than 10 years old with application of repellant. Avoid
applying repellant to young childrens hands, or around their eyes and
Protect infants by using a carrier draped with mosquito netting with an
elastic edge for a tight fit.
Antimalarial Drug Guidelines
Visit a healthcare provider familiar with travel medicine 4-6 weeks
before traveling to countries that are endemic for malaria to obtain helpful
travel information, vaccinations for other diseases, and antimalarial drug
Purchase antimalarial drugs before traveling overseas to make sure that
they are effective. Drugs bought in other countries may not be protective.
Take all drugs as prescribed before, during and after travel for
complete protection. Partial use may result in infection.
Malaria Fact Sheet for Immigrants
Malaria Fact Sheet for Haitian Immigrants
Malaria Fact Sheet for Nigerian Immigrants
Angell S, Cetron M. Health disparities among travelers visiting friends and relatives
abroad. Annals of Internal Medicine. 2005; 142(1) 67-73.
Bacaner N, Stauffer B, Boulware D, et
al. Travel Medicine Considerations for North American Immigrants Visiting
Friends and Relatives. JAMA. 2004; 291(23)2856-2864
Dos Santos C, Anvar A, Keystone J,
Kain K. Survey of use of malaria prevention by Canadians visiting India. CMAJ.
1999; 160(2) 195-200.
Franco-Paredes C, Santos-Preciado J.
Problem pathogens: prevention of malaria in travelers. Lancet Infectious
Diseases. 2006; 6:139-49.
Fulford M, Keystone J. Health risks
associated with visiting friends and relatives in developing countries.
Tropical and Travel Medicine.
McCarthy M. Should visits to
relatives carry a health warning? Lancet. 2001; 357 (9259) 862.