Division of Disease Control and Health Protection

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 protective immunity.

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 nets:
                  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 children’s hands, or around their eyes and mouth.

• 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 prescriptions.

• 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   Spanish version
Malaria Fact Sheet for Haitian Immigrants    Creole version
Malaria Fact Sheet for Nigerian Immigrants

Information from CDC: http://www.cdc.gov/malaria/travelers/index.html

References

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.