With the summer months fast approaching, pharmacists should up their travel health retail offering, writes Rod Tucker
Many more people are travelling internationally and excursions to distant countries offer a wealth of new experiences. However, travelling can be problematic – especially when illness strikes. Nevertheless, careful planning will help minimise the potential risks that may arise either en route or while at the holiday destination.
Here are some precautions patients should think about taking before they embark on their travels:
Vaccinations offer protection against a wide range of illnesses that might be encountered in different parts of the world and are normally administered a few weeks before travel. Though the specific vaccines required for different countries can be found online,1 it is advisable to vaccinate against hepatitis A, which can be acquired from eating and drinking, as well as hepatitis B, which can be transmitted from infected individuals.
Malaria is an endemic disease in the tropical and sub-tropical regions of the world that kills millions of people every year. It is caused by the parasite plasmodium and transmitted through mosquito bites. Though malaria does not occur naturally in the UK, figures show that there were 1,400 cases in 2015, most of which were due to those who had travelled abroad2 and had not taken malaria prophylaxis.
The most recent guidance from Public Health England emphasises that malaria prophylaxis involves a combination of measures including awareness of the risk, bite prevention measures, chemoprophylaxis and prompt diagnosis where the disease is suspected.3 Advice on the specific regimes to use in different countries is detailed in the British National Formulary.
Deep vein thrombosis
Traveling for any length of time invariably results in long periods of immobility that can increase the risk of a deep vein thrombosis (DVT), which is a partial or even complete blockage of a vein due to a blood clot. Prolonged episodes of immobility slow blood flow through the veins, leading to blood pooling and coagulation, increasing the likelihood of clot formation. A pulmonary embolism is a serious and life-threatening complication of a DVT that occurs when a part of the clog breaks and travels to the lungs.
Risk factors for a DVT include increasing age (over 60 years), pregnancy, obesity, use of oral contraceptives and a history of a DVT. Fortunately for healthy individuals, the risk of a DVT is very low and for a flight longer than four hours, the risk is estimated to be 1 in 6,000.4 The risk of a DVT can be reduced by regularly walking during travelling. Flexing and extending the ankles encourages blood flow from the lower legs.
The risk of a DVT can be minimised if people wear loose fitting, comfortable clothing, walk around as much as possible and maintain adequate hydration. Many travellers now wear compression stockings for flights, which are thought to work by exerting a graduated pressure on the leg (which is greatest at the ankle) and when combined with movement, helps displace blood from the superficial to deep venous system.
There is good evidence that using compression stockings can reduce the incidence of an asymptomatic DVT by as much as 90%.5 Compression class 1 should be sufficient for flights and this will also reduce leg oedema – though it is important that are stocking are measured to ensure that the correct size is used.
This is a common problem especially among children but it can also affect adults. The constant movement during travel, whether in rough seas or as a car or bus travels around corners or over bumps in the road, causes the brain to receive conflicting information from the inner ears (which detect motion) and the eyes, leading to nausea, sweating, feeling cold and paleness.
General advice to help reduce motion sickness includes sitting in the front seat of a car, over the wings of a plane and in the middle of a boat. It is also advisable not to read or watch a film and to try, wherever possible, to avoid heavy meals or alcohol.
There are a range of potential treatments for motion sickness from a pharmacy including hyoscine (Kwells®, Joy Rides®), which is considered to be the most effective, and various anti-histamines such as promethazine (which is useful for children) and cinnarizine and cyclizine that can be taken by adults.
Insects such as mosquitos are attracted by our body heat, odours and carbon monoxide. Using an insect repellent helps not just to prevent transmission of diseases but to stop nuisance biting, which can lead to allergies.
There are several different commercial insect repellents available and all will protect against mosquitos, sand flies and ticks. These agents appear to work by affecting the insect’s antennae, stimulating avoidance behaviour or by blocking their receptors for attractive odours.
The most common repellents are:
DEET has been in use since 1946 and is considered the ‘gold standard’ repellent. It is safe to use in both pregnant women and children from two years of age. It is available in concentrations ranging from 20-100% and the duration of protection depends on the concentration.
However, there are no advantages to using products with more than 50% DEET and a 20% formulation should provide protection for between six and 13 hours, though it needs to be re-applied if a person sweats heavily or goes swimming. In addition, DEET can be used with sunscreens (see below) and patients should be advised to apply the repellent before or at the same time as a sunscreen. Recent studies have demonstrated that some species of mosquitos are tolerant to the effects of DEET and continue to bite.
All other agents appear to be effective and people should take note of the recommendations for use provided by the manufacturer since one of the main reasons for treatment failure is incorrect use. Another effective deterrent is the use of a diffuser device.
If bitten by mosquitos, hydrocortisone cream 1% will be effective in most cases. Alternatives include mepyramine maleate cream (Anthisan®) though this is less effective. Oral antihistamines can also be used and solutions will help children.
Protecting the skin against sunlight
Sunscreens can be used to provide a degree of protection against the risk of sunburn caused by radiation. The level of protection offered against burning is determined by the sun protection factor (SPF). This has been described as a measure of how much longer a person can stay in the sun without burning. For example, if someone normally burns after 20 minutes in the sun, applying a sunscreen with an SPF of 15, means that they can stay 15 times longer (i.e. 300 minutes or 5 hours) before they would burn.
Unfortunately, this is a common misconception because although increased time in the sun increases exposure, the intensity of solar radiation varies depending on the time of day, the season, latitude, altitude and reflection from sand, water or snow. The SPF can be thought of as providing a relative, rather than absolute, measure of protection. Sunscreens range in SPF from 15 to 50 though the difference in the amount of UVB radiation blocked is relatively small.
Protection against UVA radiation is measured using a rating system from 1 to 5 (highest). Patients should therefore look for a product that has a high SPF and UVA rating.
Sunscreens can be used in children but more important is seeking shade, covering up and wearing a hat and sunglasses. The elderly also need to practice sun protection since the risk of skin cancer increases with age and they should avoid going out in direct sunlight between 10am and 3pm.
Food can be a source of salmonella, campylobacter, E Coli and norovirus leading to travellers’ diarrhoea and it is advisable to avoid ice-cream or ice in drinks in places where tap water shouldn’t be drunk. Fortunately, most cases of traveller’s diarrhoea only require fluid replacement and it is advisable to carry oral rehydration sachets although anti-diarrhoeal treatments like loperamide can be used for one or two days to reduce the number of visits to the toilet, especially if travelling.
Pharmacist travel health clinics
Specific travel health clinics in pharmacies represent a potentially useful additional service for patients, particularly as some research suggests that more than half of travellers received no vaccinations before visiting high risk areas.6 The accessibility of pharmacists offers patients a convenient means of obtaining vaccinations and travel health advice. In fact, several pharmacists around the UK have already established a travel health service through which patients are vaccinated, offered advice and supplied with anti-malarial medicines, first-aid kits and insect repellent products.
Interested pharmacists should endeavour to undertake further training and Valneva has launched a support program for pharmacists wishing to become more involved in travel health services.7
https://travelhealthpro.org.uk/countries [Accessed March 2018]
https://travelhealthpro.org.uk/factsheet/54/venous-thromboembolism [Accessed March 2018]
https://vip.valnevauk.com/home/?confirmedhcp=1 [Accessed March 2018]