Guidelines for Malaria Prevention in Travellers from the UK
Malaria is a preventable, life-threatening disease transmitted by the bite of the female anopheline mosquito. While the disease is not endemic in the UK, approximately 2000 cases of malaria occur every year in travellers returning to the UK from malaria-endemic countries.
Malaria is predominantly a disease affecting Africa, South and Central America, Asia and the Middle East. The heaviest burden is in Africa, where around 90% of approximately one million deaths from malaria worldwide occur each year.
The Advisory Committee on Malaria Prevention for UK Travellers (ACMP) has produced guidelines of essential information on malaria prevention for healthcare workers who advise travellers, entitled: Guidelines for Malaria Prevention in Travellers from the United Kingdom for 2003. The guideline consists of eight sections:
Section 1: purpose and scope of guidelines
Section 2: summary recommendations
Section 3: issues considered in producing guidelines on chemoprophylaxis for malaria
Section 4: advising travellers
Section 5: detailed recommendations
Section 6: recommendations by area
Section 7: surveillance
Section 8: future prospects
To follow are sections 1 and 2 of the guidelines. Or download the full guidelines [PDF].
1. Purpose and scope of guidelines
These guidelines on malaria prevention are designed to aid healthcare workers who advise travellers, particularly those who will be overseas for less than a year. The present (to May 2003) revision is the responsibility of the Health Protection Agency Advisory Committee on Malaria Prevention for UK Travellers (ACMP; membership given at the end of the full guidelines).
The full guidelines are in three parts. The first part is a summary that emphasises modifications to the advice given in the recent guidelines, published in 1997 and 2001. As oversimplified lists of recommendations by country can be misleading, the second part (sections 3-4 in the full guidelines) discusses the issues addressed in formulating the guidelines. The second part also addresses the healthcare worker’s consultation with prospective travellers. In concept and practice, chemoprophylaxis lies somewhere between vaccinations (for which people expect governments to lay down schedules) and treatment of ill people (which is determined by individual clinical need and choice).
The risks of malaria need to be balanced against the risks of the preventive measures, on the basis of the data available. Travellers may ask for an explanation of these risks and doctors and practice nurses need to be well informed and able to present this information to travellers. Doctors, practice nurses and pharmacists are asked to read this section to ensure that due attention is paid to the traveller’s history and destination.
The third part (sections 5-8 in the full guidelines) gives specific recommendations for travellers to named destinations and some details of individual drugs. Fuller information on some drugs now less used was given in early versions of the guidelines.
These guidelines reflect a broad range of expert professional opinion. Data are inadequate for unequivocal views to be given on several issues, but all available evidence has been taken into consideration. There is often a range of acceptable options, but to meet the requests of general practitioners the guidelines aim to give one recommended option and state the alternatives, suggesting when and how different regimens can be used to good effect. However, there are now several options for effective prophylaxis of highly chloroquine-resistant falciparum malaria, and the choice between them will depend on details of the journey and individual preferences. The choice should involve adviser and traveller, with the aim of improved compliance.
Authorisation to market drugs for use in the UK is the responsibility of the Medicines and Healthcare products Regulatory Agency (MHRA), advised by the Committee on Safety of Medicines, not of the ACMP. The guidelines should therefore be read as a supplement to and not as a substitute for the relevant summaries of product characteristics (SPCs or ‘data sheets’).
The second part (sections 3-4 in the full guidelines) of these guidelines may also be of use to prospective travellers who wish to read about the options themselves. All readers are recommended to read part three (sections 5-8 in the full guidelines) in its entirety to get a balanced picture.
2. Summary recommendations
Four steps remain essential to prevent damage to health due to malaria in UK travellers:
- Awareness: know about the risk of malaria
- Bites by mosquitoes: prevent or avoid
- Compliance with appropriate Chemoprophylaxis
- Diagnose breakthrough malaria swiftly and obtain treatment promptly
Recent guidelines give greater emphasis to the importance of balancing the risk of malaria and the risk of adverse reactions to antimalarials. This depends upon:
- place to be visited
- duration of the visit
- degree of exposure
- level of drug resistance
- type of traveller
All these factors affect the risk of malaria. Whereas most adverse reactions to antimalarials occur within the first few doses, the cumulative risk of contracting malaria is roughly proportional to the length of stay in a malarious area. The longer the stay, therefore, the more important it is to use a regimen with a high protective efficacy.
It is more important to take an effective antimalarial regimen regularly than to agonise too much over which one to take. When two choices are finely balanced the wrong course of action is to take neither. In travellers who develop fever or a flu-like illness within three months after possible exposure to malaria the need for prompt medical attention cannot be overemphasised. It is also desirable to keep a sense of proportion between malaria and other health problems related to travel and to remember that malaria is both relatively preventable, and treatable if diagnosed early. At present, between 0.5% and 1% of falciparum cases in the UK die of the disease.
The range of antimalarials for protection against highly chloroquine-resistant malaria is expanding. In addition to the highly effective mefloquine which has a weekly regimen, doxycycline is now licensed for malaria prevention. Atovaquone/proguanil (Malarone), now licensed for prophylaxis, is increasingly being considered, especially for brief visits to highly malarious areas. In the case of mefloquine, increased awareness of distressing adverse neuropsychiatric reactions indicates caution in its use, but it remains of great value where there is intense exposure to malaria that is highly resistant to chloroquine.
It is important to observe contraindications to the use of specific antimalarials, and especially not to give mefloquine to people with a history of epilepsy or psychiatric illness, including depression. Chloroquine is relatively contraindicated in people who have had fits or who have psoriasis. Doxycycline is being used more often for those unable to take these drugs and going to high-risk areas, but it does carry a small risk of photosensitisation.
The preferred chemoprophylaxis for the few areas without chloroquine resistance is chloroquine. Those unable to take chloroquine should take proguanil. For areas such as South Asia (the Indian subcontinent), with low or moderate levels of transmission of falciparum malaria that is slightly or moderately resistant to chloroquine, the preferred chemoprophylaxis is at present proguanil plus chloroquine.
Chemoprophylaxis is not recommended for places where there is a very low risk of acquiring highly multidrug-resistant malaria as the risk of adverse effects exceeds the risk of contracting the disease, but travellers are urged to maintain a high degree of awareness and seek immediate diagnosis and treatment of any febrile illness.
In areas with a high or very high risk of malaria that is strongly chloroquine resistant the frequency of adverse reactions to chemoprophylaxis has to be balanced against the risk of severe malarial illness and of death from falciparum malaria. The overall prevalence of adverse reactions, and of discontinuing chemoprophylaxis because of them, is comparable between regimens. Recent data indicate a significant frequency of subjective distressing neuropsychiatric adverse effects with mefloquine, but the results of different studies vary considerably. In the absence of recognised contraindications it is impossible to predict which individuals will suffer from these side effects.
On the other hand, mefloquine continues to have a substantially greater protective efficacy in East Africa, for example, than proguanil plus chloroquine. Therefore, for most of Africa, proguanil plus chloroquine is not recommended unless neither mefloquine, nor doxycycline, nor atovaquone/proguanil, can be taken.
Full recommendations by country and person are set out in part three (sections 5-8 in the full guidelines). Alternative regimens are usually given for travellers unable for any reason to take a recommended regimen.
Sources of advice on malaria prevention for travellers
The information below gives sources of advice for doctors and practice nurses who need more detailed advice for specific problems than this paper provides.
HPA Malaria Reference Laboratory (MRL) (at London School of Hygiene and Tropical Medicine): 020 7636 3924
National Travel Health Network and Centre (NaTHNaC): 020 7380 9234
Glasgow, SCIEH for Travax users only, 2-4pm: 0141 300 1130
Birmingham Heartlands Hospital (Infectious Disease Unit): 0121 424 0357
Liverpool School of Tropical Medicine: 0151 708 9393
Oxford: 01865 225 214
London, Northwick Park Hospital: 020 8869 2831
Hospital for Tropical Diseases Treatment only (ask for the medical officer on duty, Patrick Manson Unit): 020 7387 9300
Recorded advice for travellers from the HPA Malaria Reference Laboratory is available on 09065 508 908 (calls charged at 100p per minute).