Up to 8 in 1000 travellers in developed countries become infected with malaria, resulting in more than 10
000 cases of malaria being imported into Europe each year (fig ).12,13
Other vector borne diseases, such as dengue and yellow fever, are also increasingly important.14
Since December 2001, following the report of six deaths possibly associated with the administration of yellow fever vaccine in elderly travellers, health professionals have expressed concern about the use of yellow fever vaccine.15–17
Millions of doses of vaccine have been administered over many years, however, with a minimum risk of morbidity or mortality, and experts agree that the benefits of yellow fever vaccination outweigh the risks.
Malaria remains the single most important disease hazard facing travellers. Adherence to antimalarial chemoprophylaxis, in addition to adopting measures to avoid being bitten, is essential. Chloroquine resistant falciparum malaria is an increasing problem in Central and South America, South East Asia, Oceania, and sub-Saharan Africa.18
Recommended prophylaxis for chloroquine resistant areas, to be discussed with the individual traveller, include mefloquine, doxycycline, and atovaquone plus proguanil (Malarone). Chloroquine continues to be recommended as prophylaxis for malaria in areas where there is no chloroquine resistance.
It is advisable for people taking mefloquine for the first time to start three weeks before departure so that if they experience side effects such as anxiety or nightmares alternative prophylactic drugs can be considered. Alternatives include Malarone one tablet daily, doxycycline 100 mg daily, dapsone plus pyrimethamine (Maloprim) one tablet weekly or chloroquine and proguanil. Malarone consists of 250 mg atovaquone and 100 mg proguanil and is of particular value for people travelling to chloroquine resistant areas.19
Prophylaxis should be started one day before entry into an endemic area and continued for seven days after leaving it.
Guidance on antimalarial chemoprophylaxis has recently been issued by the Advisory Committee on Malaria Prevention for UK Travellers (box ). Malarone, doxycycline, and mefloquine are recommended in chloroquine resistant areas. Mefloquine is recommended for travel of longer than two weeks' duration to West, Central, and East Africa and specific areas of South East Asia. Chloroquine and proguanil are recommended for travel to other areas.20
Malaria chemoprophylaxis by continent (depending on season and area visited)
Standby treatment in defined circumstances may become of increasing value to travellers. Standby treatment consists of a course of antimalarial drugs that travellers to malaria endemic areas can use for self treatment if they are unable to gain access to medical advice within 24 hours of becoming unwell. The treatment kits are supplied with written instructions, and travellers must seek medical advice as soon as possible. Recently licensed agents indicated for use as standby treatment include Malarone and Riamet, which is a new fixed dose antimalarial drug containing 20 mg artemether and 120 mg lumefantrine.21