Key learning points
- The importance of education and advice for travellers to long-haul and tropical destinations
- Reducing risk of illness in travellers
- Special considerations for younger and older travellers
During the first decade of this millenium, the number of visits overseas made by UK residents peaked at 70 million. This is includes 9 million travellers who ventured to areas outside Europe and North America in 2006 alone. This trend has continued to rise and last year, 57 million UK residents travelled abroad. It is projected that global international arrivals to the UK will reach 1.6 billion in 2020..2 Depending on their destination, travellers may be at increased risk of contracting infections, which may not be as common, or exist at all, in the UK. They should therefore be prepared for such risks, and seek advice about their health before they go abroad.1 While some travellers seek travel health advice before they leave the UK, surveys indicate that a significant number still do not see a healthcare professional before departure.3
Travellers need to seek advice sufficiently in advance of travel to high-risk destinations for the longer-term efficient and effective delivery of travel health risk management. As per the reports published by the Health Protection Agency (HPA), more attention should be given to recording travel histories from patients who contract infectious diseases following foreign holidays and trips abroad.4,5 Clearly, it is essential to make a thorough assessment of the traveler and provide appropriate advice. However, there is sufficient evidence that inadequate advice is being given to travelers by healthcare professionals who are not sufficiently trained, including malaria prevention advice,6 and this is having serious consequences for the morbidity and mortality of travellers.7 The Royal College of Nursing (RCN) competencies for travel health suggest that at least 20 minutes per patient should be allowed, and more time than that if malaria should be discussed. Frequently a family of five will be given a 30 minute appointment, for five individuals with different needs, with children who are at special risk of travel health issues because of their lack of understanding of risks.8 It is also essential that the travel consultation focuses on the health education of the individual traveller.9 Behaviour changes, together with the correct administration of vaccines and malaria chemoprophylaxis, are often necessary to prevent health problems when travelling abroad.
Malaria: the most common arthropod-borne infection in travellers
Malaria, an almost completely preventable but potentially fatal disease, remains an important issue for UK travelers. As per the HPA, based on figures reported to the HPA Malaria Reference Laboratory (MRL), there were 1,677 cases in 2011, 1,761 cases of malaria in 2010, 1,495 in 2009, and 1,370 reported in 2008. This trend is against a background of falling malaria incidence globally over the last five years, and probably reflects greater travel to malaria-endemic areas. In 2011, 69% of malaria cases were caused by the potentially fatal Plasmodium falciparum (compared with 72% in 2010) and this high proportion of falciparum malaria reflects the fact that most malaria imported to the UK is acquired in Africa. The proportion due to vivax malaria has however also risen in recent years, mainly as a result of increased vivax cases acquired in Pakistan; 182 reported in 2011 compared to 73 in 2010 and 46 in 2009.10
Risk factors for malaria in travellers
Anyone travelling to a malaria region is at risk. This includes anyone originally from a country with malaria now living in a malaria-free country. People born and brought up in areas with malaria may develop some immunity but this disappears quickly once they leave. Parents do not pass on malaria immunity to children. Babies and young children are particularly likely to become seriously ill with malaria.11 Exposure of individual travellers to malaria is influenced by the number of infectious bites received, which is affected by a number of factors, some of which are listed below:1
- Temperature, altitude and season. High humidity and an ambient temperature in the range 20-30°C favour malaria transmission. Maturation of the parasite in mosquitoes usually doesn’t take place at altitudes greater than 2,000 meters. Seasonal rainfall increases mosquito breeding thereby increasing the chances of getting infected.
- Location and type of accommodation. Incidence is generally higher in rural than in urban areas, especially in Africa where the intensity of transmission is on average about eight times higher in villages than towns. Backpackers staying in cheap accommodation have a higher risk of being bitten compared to tourists staying in air-conditioned hotels.
- Patterns of activity. Remaining outdoors between dusk and dawn when Anopheles mosquitoes bite increases the risk of transmission.
- Length of stay. The longer the stay in a malaria region, the higher the risk of getting infected.
Risk of dying from malaria increases if there is a lack of awareness of the risk, inadequate prophylaxis or taking the wrong prophylaxis for the destination, mistaking malaria for another illness, such as flu, and any delay seeing a doctor or starting treatment.11
Special risk groups
Certain travellers are at particular risk of acquiring malaria and are not being reached by health messages about the importance of antimalarial prophylaxis. Of those who had malaria diagnosed in the UK, where ethnicity was known, 136 were reported as white British, compared with 938 who were reported as African or of African descent, and 395 reported as Asian or of Asian descent. The burden of falciparum malaria in particular falls heavily on those of African ethnicity, and this group is important to target in pre-travel advice.10 People travelling to visit friends and relations are at greatest risk from diseases such as malaria because they don’t fully understand the risks. They have incorrect, pre-conceived ideas that they have natural protection against the disease, and may stay longer at hazardous locations such as rural areas.9
Guidelines for malaria prevention in travelers from the UK
As per the latest guidelines for malaria prevention in travelers from the UK, put forward by Public Health England Advisory Committee on Malaria Prevention (ACMP), a four pronged ‘ABCD’ approach – awareness of risk, bite prevention, chemoprophylaxis, prompt diagnosis and treatment - should be used:1
A = Awareness of risk
Travellers should be provided with the relevant information about malaria, its transmission, clinical symptoms and signs, and various risk factors affecting its incidence.
B = Bite prevention
This should be the first line of defense against malarial infection. Various approaches can be used to prevent mosquito bites, such as use of repellants, insecticides, nets, clothing, and room protection. The ACMP recommends DEET (N,N-diethyl-m-toluamide)-based insect repellents, as concentrations over 20% give a longer duration of protection than other available repellants.
Duration of protection is one to three hours for 20%, up to six hours for 30% and up to 12 hours (maximum) for 50% DEET. This repellant reduces the efficacy of sunblock, therefore, when both sunscreen and DEET are required, DEET should be applied afterwards. DEET is recommended by AMCP for all individuals over the age of two months, unless they are allergic to it. Other repellants that are used but have shorter duration of action include p-menthane-3,8-diol (lemon eucalyptus), Icaridin (Picaridin), 3-ethlyaminopropionate, and oil of citronella.
Insecticides that are used include Permethrin and other synthetic pyrethroids and these have a rapid knock-down effect on mosquitoes and are used to kill resting mosquitoes in a room. If sleeping outdoors or in unscreened accommodation, insecticide-treated mosquito nets should be used. Protective efficacy of impregnated nets for travelers has been estimated at 50%. These nets must be free of tears and should be tucked in under the mattress. Most of the nets currently available are long-lasting (expected useful life of at least three years) impregnated nets, in which the pyrethroid is incorporated into the material of the net itself or bound to it with a resin. Regarding clothing, within the limits of practicality, covering up with loose-fitting clothing, long sleeves, long trousers and socks if outdoors after sunset, minimises accessibility to skin for biting mosquitoes. Clothing may be sprayed or impregnated with an insecticide or purchased pre-treated to reduce biting through the clothing. Air conditioning reduces the likelihood of mosquito bite as a result of substantial reduction in night-time temperature. Ceiling fans reduce mosquito nuisance. Doors, windows and other possible mosquito entry routes to sleeping accommodation can be screened with fine mesh netting which must be close-fitting and free from tears. The room can be sprayed before dusk with a knockdown insecticide (usually a pyrethroid) to kill any mosquitoes that may have entered the accommodation during the day. During the night, where electricity is available, a proprietary heated liquid reservoir device containing insecticide or an electrically heated device to vapourise a ‘mat’ (tablet) containing a synthetic pyrethroid in the room can be used. Alternatively, a mosquito coil containing insecticide can be burnt, which will repel and kill mosquitoes.
C = Chemoprophylaxis
Prior to travelling, medications required for chemoprophylaxis should be obtained from a reputable source. Drugs commonly used for chemoprophylaxis include chloroquine, proguanil, mefloquine, doxycycline, and atovaquone either individually or in combination. The has the UK health Protection Agency Malaria Refernce Laboratory which is the national reference center for malaria diagnosis in the UK and also recommended different drugs for chemoprophylaxis in different countries or travel destinations.
D = (Prompt) Diagnosis and treatment
Medical attention should be sought as soon as possible for full assessment and to exclude other serious causes of fever. This is particularly important as many illnesses other than malaria may present with fever. Emergency standby treatment should be recommended for those taking chemoprophylaxis and visiting remote areas where they are unlikely to be within 24 hours of medical attention only if backed up with written information and full counselling. Antipyretics should be used to treat fever.
Yellow fever is rare in travelers, but since 1996 there have been six fatal cases in European and US travelers. All the fatal cases were in unvaccinated travelers. This disease is caused by a virus that is spread through the bite of an infected Aedes aegypti mosquito which predominantly bites during daylight hours. It is endemic in tropical regions of Africa and South America where the World Health Organization estimates approximately 200,000 cases occur each year, with 30,000 deaths.1
Yellow fever can be prevented by preventing mosquito bites and getting the yellow fever vaccine at least 10 days before the day of travel, and travellers to yellow fever areas should do both. The methods for preventing bites are same as those discussed above for malaria. The vaccine has been used for more than 80 years. It works very well and lasts for a long period of time. Most people do not have any problems with the vaccine. Vaccination can only be given in approved yellow fever vaccination centers and is recommended for personal protection for all travelers aged nine months and older to countries with a risk of yellow fever.12 At present both in the UK and globally there is a shortage of yellow fever vaccine, which is mandatory in some West African and South American countries, and this situation is likely to continue until January 2014. An unexpected manufacturing issue has led to a delay in the availability of the single dose vial plus pre-filled syringe presentation of Stamaril®. Sanofi Pasteur MSD has sourced a multi-dose presentation of Stamaril® to ensure that doses are still available within the market. The multi-dose vials contain 10 doses and come as a box of 10 vials (ie. 100 doses). These have been priced the same as 100 doses of the single presentation. Very few clinics have the amount of patients to provide 10 clients within the six-hour window of time required to use up the multi-dose vial. Failure to reach this number will lead to financial loss for practices and wasted doses mean some people will be unprotected against this potentially deadly disease.12
Health issues in young travellers
This relates particularly to children under five years old. Road traffic accidents and drowning incidents are the leading causes of death in child travelers.9 Risk of illness such as malaria, or travellers’ diarrhoea can be more severe. Small, mobile and inquisitive toddlers have limited hygiene awareness - put fingers in mouths, touch everything - which leads to increased risk of faecal orally-transmitted illnesses and dehydration. Rabies is more common in children than adults.13 Children being curious, will go and poke sleeping animals, they are also less likely to admit if they are bitten scratched or licked, as they will have been warned by their anxious parents not to do it. Careful supervision is needed as there is increased risk of other hazards such as sunburn and heat exposure.8
Health issues in older travellers
Older travellers tend to have poorer immune systems leaving them at more risk of infection and developing serious complications. They are more likely to have accidents and pre-existing medical conditions such as diabetes, or heart disease may lead to complications. There is increased risk of sexually transmitted diseases in the over 50 year old age group in today’s society,5 as condoms may be perceived as irrelevant once the fear of pregnancy has passed. Moreover, there is greater risk of serious adverse events following a first dose of yellow fever vaccine in those over 60 years.15 Mortality from malaria increases with age in the UK and elderly travelers need to be targeted for pre-travel advice.7
1. Guidelines for malaria prevention in travelers from the UK. London: Public Health England; 2013. Available at: www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1203496943523
2. World Health Organization. Health risks and precautions: general considerations in International travel and health 2010. Geneva: WHO; 2011. Available at: www.who.int/ith/ITH2010chapter1.pdf
3. Health Protection Agency. Foreign travel-associated illness–a focus on those visiting friends and relatives. London: HPA; 2008. Available at: www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1231419800356
4. Health Protection Agency. Foreign travel-associated illness: England, Wales and Northern Ireland. London: HPA; 2007. Available from: www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1204186182561
5. Health Protection Agency. Foreign travel associated illness–a focus on travelers’ diarrhea. London: HPA; 2010 [cited 2013 November 5]. Available from: www.hpa.org.uk/web/HPAwebFile/HPAweb_C/1287146380314
6. Chiodini J. The standard of malaria prevention in UK primary care. Travel Med Infect Dis 2009;7(3):165-8.
7. Checkley AM, Smith A, Smith V, Blaze M, Bradley D, Chiodini PL, et al. Risk factors for mortality from imported falciparum malaria in the United Kingdom over 20 years: an observational study. BMJ 2012;27(344):e2116.
8. Chiodini J, Boyne L, Stillwell A, Grieve S. Travel health nursing: career and competence development, RCN guidance. London: RCN; 2012. Available at: www.rcn.org.uk/__data/assets/pdf_file/0006/78747/003146.pdf
9. Field VF, Gautret P, Schlagenhauf P, Burchard GD, Caumes E, Jensenius M, et al. Travel and migration associated infectious diseases morbidity in Europe, 2008. BMC Infect Dis 2010;17(10):330.
10. Health Protection Agency. Health Protection Report. London: HPA; 2012. Available at: www.hpa.org.uk/hpr/archives/2012/hpr1712.pdf
11. National Travel Health Network and Centre. Health information for overseas travel: ‘Yellow Book’. Field VK, Ford L, Hill DR, editors. London: NaTHNaC; 2010. Available from: www.nathnac.org/yellow_book/YBmainpage.htm
12. National Travel Health Network and Centre. Yellow Fever Vaccine Shortage. London: NaTHNaC; 2012. Available from: www.nathnac.org/pro/misc/yfvaccine_supply.htm#unlicensed
13. Warrell MJ. Current rabies vaccines and prophylaxis schedules: preventing rabies before and after exposure. Travel Med Infect Dis 2012;10(1):1-15.
14. Hagmann S, Neugebauer R, Schwartz E, Perret C, Castelli F, Elizabeth D, et al. Illness in Children After International Travel: Analysis From the GeoSentine Surveillance Network. Pediatrics 2010;125(5):e1072-1080.
15. Khromava AY, Barwick Eidex R, Weld LH, Kohl KS, Bradshaw RD, Chen RT, Centron MS. Yellow fever vaccine: an updated assessment of advanced age as a risk factor for serious adverse events. Vaccine 2005;9;23(25):3256-63.
You are currently leaving the Nursing in Practice site. Are you sure you want to proceed?