TRAVEL HEALTH
By the end of this chapter you should be able to:

Give advice on the timing and administration of three drugs for the
prevention of travel sickness.

Give two pieces of practical advice for the management of jet lag.

Give at least four pieces of advice to reduce the risk of skin damage on
exposure to sun.

List at least 10 essential items for a medical kit suitable for an
individual travelling in the tropics.

List drugs used in the prophylaxis of malaria and their side effects.
TRAVEL HEALTH ............................................................................................ 1
Travel sickness ......................................................................................... 5
Exercise 1 ................................................................................................. 6
Jet Lag ...................................................................................................... 7
Sun ........................................................................................................... 7
Exercise 2 ................................................................................................. 9
Medical kits ............................................................................................. 10
MORE COMMON TRAVEL DISEASES ................................................. 10
Exercise 3 ............................................................................................... 16
Exercise 4 ............................................................................................... 26
SUMMARY ............................................................................................. 27
Reflection Box......................................................................................... 28
ANSWERS TO EXERCISES .................................................................. 29
References ............................................................................................. 32
BACKGROUND
In recent years there has been an In addition, a wider range of people are
enormous increase in the number of people travelling between the different
countries of the world, and the World Health Organisation estimates that
annual arrivals at all destinations total over 4000 million.
Residents of the United Kingdom make over 40 million trips abroad each year.
Increasingly, people are visiting not only European countries and North
America, but also tropical countries and areas off the usual tourist track,
where risks to health may be greater. Different countries and regions have
their own public health risks that travellers are exposed to during their trips.
Safeguarding their health by provision of accurate information and
preventative measures forms the public health aspect to this group of people.
In addition, a wider range of people are travelling than previously. Twenty
years ago, older people, individuals with various conditions, such as diabetes
and epilepsy, disabled people and young babies did not travel overseas as
frequently as they do now. Some of these people may be at particular risk and
would therefore benefit from additional advice from you.
The increase in numbers of air passengers in Scotland is illustrated on page
283. Many United Kingdom statistics are available at
http://www.statistics.gov.uk and covers many areas, not just health. For
statistics with a Scottish slant the Scotstat website may be of use
http://www.scotland.gov.uk/stats/scotstats.asp
Air Terminal Passengers at Airports (Scotland)
This chapter covers the health needs of travellers to developed and
developing countries but excludes the needs of those on “expeditions” and
also expatriates, although some of the issues will be the same.
Pharmacists can provide health advice to travellers at three levels:

Pre-travel advice (health promotion and disease prevention)

Supply of medicines and medically-related products

Response to symptoms on return from travel

In the future, pharmacists could supply and administer travel vaccines
under a patient group directive, or eventually as independent
prescribers.
TRAVAX™ is provided for Health Care Professionals and is maintained and
continually updated by the Travel Medicine Team at Health Protection
Scotland (previously Scottish Centre for Infection and Environmental Health).
Pharmacists can register free of charge to Travax at www.travax.nhs.uk. This
is an invaluable information source and you should make a point of consulting
it in all the instances in this chapter where you see TRAVAX.
ENVIRONMENTAL AND OTHER HAZARDS ASSOCIATED WITH TRAVEL
International travellers are subject to various forms of stress, which may affect
their health and reduce their resistance to disease. Long hours of waiting at
crowded airports, disruption of eating and sleeping habits, changes in climate
and time zone, and also new or different activities from those undertaken at
home can lead to anxiety, insomnia and exhaustion.
Fear of flying is a real problem for some people, and an estimated nine million
people in the UK suffer from anxiety and panic when they fly
Individuals with a history of mental illness, who are planning to travel in
countries where the culture and lifestyle is very different from their own,
should consider having a thorough psychological review. At the very least
they should be encouraged to think through their travel plans carefully.
Travel sickness
Travel motion sickness can be reduced by choosing the most stable part of
the vehicle – between the wings of an aeroplane, in the front seat of a car and
the middle of a boat. If travelling by boat, it is best to be on deck, looking at
the horizon. Limiting food and alcohol, taking adequate fresh air, and lying
down if possible are also sensible measures. Other practical measures may
involve lying horizontally, avoiding reading, trying distraction techniques and
avoiding stuffy or smoky atmospheres
Medication
An anti-emetic may help. Some anti-emetics are available “over the counter”.
A doctor’s advice should be sought if the problem is severe.
DRUG NAME
ADULT DOSE
DURATION OF
ACTION
Cyclizine (Valoid)
50mg
4 to 6 hrs
Hyoscine tablets
0.3 - 0.6mg
4 to 6 hrs
25mg
24 to 30 hrs
Meclizine (Sealegs)
25mg
6 to 12 hrs
Cinnarizine (Stugeron)
30mg
6 to 8 hrs
(Scolpalmine)
Promethazine
(Avomine)
Hyoscine patches may be useful for long journeys (e.g. at sea) in those over
10 years of age. They are normally applied to the skin every 3 days.
(T)
Exercise 1
A patient, who suffers occasionally from travel sickness, asks you if there are
any alternative/natural remedies for this condition.
What is your response?
Please write your answer below.
Jet Lag
The crossing of several time zones disrupts the body’s circadian rhythms,
particularly those associated with sleep, waking, hunger and defecation.
However, it is changes in sleep patterns that cause travellers most concern.
Normally at least five time zones have to be crossed (that is, five hours time
difference ) before jet lag is appreciable and it is experienced to a greater
extent travelling east – when the travel day is lengthened – than when
travelling west – when the travel day is shortened.
Adjustment may take a week or more and may be exacerbated by increasing
age. Symptoms may include indigestion, disturbance of bowel function,
general malaise, daytime sleepiness, difficulty sleeping at night and reduced
physical and mental performance. There is little that can be done about jet lag
and symptoms gradually wear off as the body adapts to the new time zone. if
possible travellers should schedule some short periods of rest during the day
until adjustment has been achieved, but it is best to try not to alter usual
sleeping hours too much. Other measures include limiting alcohol and
caffeine consumption to prevent undue sleep disruption
Sun
A number of long term complications can develop as a result of prolonged
exposure to ultraviolet (UV) rays. These can range from common issues such
as sunburn, infection of the skin if sunburn blisters and bacteria enter,
premature ageing and more serious complaints such as photokeratitis
(sensitivity of the eyes known as snow blindness) and melanoma and non
melanoma skin cancer. Skin cancer accounts for about 14 per cent of cancer
incidence in the UK, with around 70,000 people developing the disease, with
both melanoma and non-melanoma cancer is increasing.
Malignant melanoma of the skin is in the top 10 most commonly occurring
cancers in Scotland. While it only occurs with a frequency of 3.7% it shows a
30% increase in frequency over the last 10 years.
Those most at risk include infants and children and those with pale skin,
which burns easily, red hair, freckles or a large number of moles, or a family
history of the disease. Also people on immunosuppressant medication may be
at higher risk. People with brown or black skin have a much reduced risk of
skin cancer.
Non – melanoma skin cancer is a general term used to refer to a group of skin
cancers that affect the upper layers of the skin. The two most common types
are basal cell carcinoma and squamous cell carcinoma which are generally
deemed less serious cancers. There is estimated 100,000 new cases each
year with the most significant risk factor being over exposure to sunlight
Registrations for malignant melanoma (Scotland)
GRAPH INSERTED HERE
The use of sunscreens reduces the risk of sunburn, but whether they prevent
skin cancer is controversial, not least because in preventing sunburn they
may encourage longer exposure to the sun. Traditionally, most sunscreens
work mainly by blocking solar ultraviolet B wavelengths (295-320 nm), which
despite accounting for less than 5% of solar radiation are primarily
responsible for sunburn. There is increasing evidence that ultraviolet A (320-
400 nm) can also damage skin and most sunscreens in the UK provide good
ultraviolet A and ultraviolet B protection. There is a voluntary star system in
the UK to help consumers decide what protection they need. The higher the
star, the greater the UVA protection. The SPF, sun protection factor, refers
to protection against UVB (e.g. SPF 8 allows 8 times longer sun exposure
without burning than with no protection). To gain effective protection use a
broad spectrum cream which protects against UVA and UVB. A SPF of 15
and above is generally recommended with liberal application every 2 hours.
Sunscreens are expensive and people should be wary of cheaper versions
bought abroad which may not give adequate protection. Waterproof
sunscreens are available and can prevent their removal by sweat or water.
They should always be reapplied after swimming.
There have been reports of increased malignant melanoma in sunscreen
users. One reason suggested for this is that ultraviolet A wavelengths may be
particularly important in inducing skin cancer. While British sunscreens
provide ultraviolet A protection, sunscreens in other countries may not.
Sunscreens providing protection against ultraviolet B waves protect against
sunburn, encourage increased exposure to the sun, and could therefore
increase exposure to ultraviolet A. Another idea is that sunscreen may provide
little protection against the immunosuppressant effects of ultraviolet radiation,
and immunosuppression is thought to increase the risk of skin cancer.
The role of sunscreens in cancer needs clarification, but it is important that
individuals do not use sunscreens as an excuse to increase the amount of
time spent in the sun – for example, staying out in the sun for three hours
rather than 20 minutes.
Exercise 2
A patient mentions to you that she has not been abroad for several years and
is “rather looking forward to getting a tan”. What advice would you give to
reduce the risk of skin damage in herself and her three children?
Please write your answer below
Medical kits
A medical kit should be carried for all destinations where there may be
significant health risks, particularly those in developing countries and / or
where the local availability of specific medications is uncertain
Medical kits
A suggested list of essential items suitable for travellers:

Personal medication – certain categories of prescription medicines may
require a letter signed by a physician certifying that the traveller
requires the medication for a medical condition.

Paracetamol or other simple analgesic

Oral rehydration therapy

Loperamide

Iodine tincture (for water purification and wound care)

Condoms and oral contraceptives

Antimalarial medication

Insect repellent (DEET)

Mosquito nets

Sunblock preparation and lipsalve

Needle/syringe , tweezers

Hydrocortisone cream 1% (for bites, rashes)

Antihistamine tablets

An antifungal cream/powder (for example, clotrimazole, miconazole)

Dressings, adhesive plasters, steristrips, tape, scissors, safety pins
Possibly stand-by treatment for malaria and a course of antibiotics (targeting
the most frequent infections in travellers example, ciprofloxacin,
metronidazole for travellers’ diarrhoea and infections of skin and soft tissue)
MORE COMMON TRAVEL DISEASES
Travellers’ diarrhoea
Diarrhoea is by far the commonest cause of illness in travellers, affecting an
estimated 20-50 per cent of all travellers. Although the incidence of diarrhoea
among British travellers is higher in those going to Africa or the Indian subcontinent than in those going to the Mediterranean, for example, no travel is
without risk. It can cause anything from embarrassment and inconvenience to
disruption of travel and business plans, but for vulnerable people it can be
fatal, particularly if it is not treated promptly and effectively. Older or
chronically ill travellers (people with diabetes or cancer or
immunocompromised patients) may become severely ill for over a week and
often require intravenous hydration. Children also may become ill and may
take longer to recover. 4,5
Traveller’s diarrhoea can be caused by a wide variety of organisms, all of
which are spread through the faecal / oral route. Of all the micro-organisms
responsible in various incriminated foods E coli is the most significant in terms
of diarrhoea aetiology, being the cause of up to 70 per cent of cases. Other
bacteria involved include campylobacter, shigella and salmonella Symptoms
caused by each of the different micro-organisms vary.
For example, infection caused by Bacilllus cereus tends to cause sickness
more than diarrhoea and Salmonella typhi does not always cause diarrhoea.
Protozoa, such as amoeba and giardia, may cause amoebiasis and giardiasis.
With these conditions the main thing to remember is that they can be quite
refractory and symptoms may not occur until the traveller gets home. Indeed,
giardiasis is the commonest cause of diarrhoea in travellers returning from
tropical countries. However, a correct diagnosis is often missed, and
laboratory investigation of the stools is vital to confirm the presence of the
disease.
Travellers may also pick up worm infestation while travelling, and attention to
food and water hygiene is important for prevention.
Prevention is a key issue in travellers’ diarrhoea, and because contaminated
food and water are the most common sources of infections causing diarrhoea,
careful preparation and selection of food offer the best protection. Food is a
more significant source of contamination than water. In addition, scrupulous
attention to personal hygiene – washing hands before touching food – is
essential.
The appearance of food is no guide to the likelihood of contamination. Wellcooked food eaten immediately after preparation is generally safe, but cooked
food held at room temperature in tropical countries for several hours,
constitutes one of the greatest risks of food-borne disease, because bacteria
can grow at phenomenal rates at these temperatures. Tourists should view
hotel buffets with particular caution, and buying freshly prepared hot food from
street stalls is likely to be safer.
Some specific foods pose more risk than others, These include shellfish,
undercooked meat, salads, raw vegetables, unpasteurised milk, yoghurt and
ice cream. Dry foods are generally safer than moist foods.
Water is a source of contamination and drinking tap water or any other
untreated water from an unknown source is best avoided. This applies to
water for food preparation, ice cubes and for cleaning teeth. Even bottled
water cannot be assumed to be safe. Well-known brand names of bottled
waters and canned drinks should be chosen wherever possible and opened
by or in the presence of the consumer (always check seal is intact). Hot tea
and hot coffee are generally safe.
TREATMENT
Oral rehydration therapy (ORT)
Most diarrhoeal episodes in travellers last between 48 and 72 hours, and will
resolve without any specific treatment, but fluid replacement, particularly in
children and the elderly, is vital (two glasses of fluid for each bowel movement
and more if you feel thirsty) Even water (sterilised), fruit juice and carbonated
non-diet, caffeine-free drinks, such as, cola drinks, left to go “flat” can be used
for a short period but a solution containing electrolytes is preferable e.g.
Dioralyte or Electrolade. Avoid alcohol as this will make you more
dehydrated.
Treatment should begin sooner rather than later and taking regular sips rather
than drinking a large cupful at once may be easier. In general, an effective
regime to recommend for adults is a glass of oral rehydration solution for
every loose bowel motion, plus a further glass every hour.
For infants being bottle fed, it is best to give one and a half times the normal
feed volume of oral rehydration therapy plus the usual milk feed – or,
pragmatically, as much as you can get down the infant. For breastfed babies,
feeding should continue, with additional oral rehydration solution provided.
Parents should be encouraged to seek advice from a health care professional.
Anyone looking after a person with diarrhoea should be vigilant in looking for
signs of dehydration. These include small quantities of dark, smelly urine or
no urine at all, dry tongue and a weak rapid pulse. Other general symptoms
may include irritability, restlessness, sunken eyes and dry skin
Patients with these signs should be encouraged to take as much oral
rehydration solution as possible until urine volume and colour return to normal
and seek advice from a health care professional.
Patients with symptoms, such as passage of blood and mucus from the
rectum, high fever, persistent vomiting, inability to sit up or inability to drink,
should seek medical advice straight away.
Antidiarrhoeal drugs
Antidiarrhoeal drugs should not be used as a substitute for oral rehydration
therapy. This applies particularly in children and frail, elderly patients, but they
can be useful in providing prompt relief where symptoms are causing undue
inconvenience or disruption to travel plans.
Antimotility drugs, such as loperamide and co-phenotrope, provide
symptomatic relief by reducing stool frequency and abdominal discomfort, as
long as there is no visible blood in the stool. Loperamide reduces fluid
secretion caused by toxins as well as bowel motility, but does not cause the
central nervous system depression which is at risk with co-phenotrope.
However, loperamide does sometimes cause cramps and overuse may lead
to rebound constipation. Loperamide is available over the counter but the
OTC version is not licensed for children under 12 years. Dysentery and fever
are contraindications to loperamide as the drug slows GI transit time and
theoretically the expulsion of invasive bacteria.
Preparation such as kaolin and morphine and proprietary products based on
these ingredients should not be recommended.
Antimicrobial drugs
Most forms of diarrhoea will resolve within 3-5 days with rehydration only.
However if diarrhoea is severe or associated with blood or mucous in the
stool, empiric, antiobiotic self treatment may be used. Antibiotics should
improve diarrohea within 1-2 days and are effective against E coli, Shigella,
Salmonella and Campylobacter.
Empiric treatment
Antibiotic self treatment should not be recommended routinely. Travellers
should reserve antibiotics for classic TD symptoms defined as an acute illness
characterised by cramping and diarrhoea with or without fever/ dysentery.
Vomiting alone suggests food poisoning and does not warrant antibiotics.
Travellers potentially suitable for self treatment may include those travelling to
remote rural areas of high diarrhoea risk who are distant from medical help,
those with pre existing bowel problems where infection may trigger a relapse
or those with pre existing medical conditions which may compromised by
severe infection e.g. diabetes or renal failure
The antibiotic normally prescribed for adults is Ciprofloxacin. The dose for
empiric self treatment is 500mg twice daily for 1- 3 days. The antibiotic
should be discontinued as soon as diarrhoea resolves, usually within 1to 2
doses. 6,7
Travellers should be advised that if symptoms persist without improvement in
72 hours, medical help should be sought
Probiotics have been used to treat acute infectious diarrhoea in numerous
studies and although beneficial, the type and dose of probiotic has yet to be
ascertained
Prophylaxis treatment
Antibiotic prophylaxis to prevent Traveller’s Diarrhoea is no longer routinely
prescribed as it increases the likelihood of drug resistance and antibiotic
complications. Occasional exceptions may be short term critical itineraries
and chronically ill or immunocompromised patients on trips of less than 3
weeks. Ciprofloxacin 500mg daily is the usual choice but is not licensed for
this purpose
In Summary
An antibiotic should preferably be prescribed by a doctor at the time it is
needed, but many travellers, particularly those going to underdeveloped
countries for prolonged periods, wish to take antibiotics with them. However,
they are not licensed for prophylaxis purpose and if a doctor does prescribe
them, this will generally be on a private prescription.
The issue of using antibiotics for self treatment and indeed, for prophylaxis is
controversial. Some GPs will prescribe these, but some will not. There is
evidence that the quinolone antibiotics (for example, ciprofloxacin) are
effective in the treatment of travellers’ diarrhoea.
(2, 3)
The recommended dose
is 500mg twice a day for 1-3 days, but a single does of 500mg has also
shown good results.
7
The antibiotic should be discontinued as soon as
diarrhoea resolves, usually within 1to 2 doses.
Prevention and treatment of cholera is exactly the same as that for any other
diarrhoeal illness. Prevention depends on scrupulous hygiene and attention to
eating and drinking practices. Treatment is achieved by oral rehydration.
Exercise 3
A young couple arrive at your pharmacy stating that they have booked a selfcatering apartment for two weeks in August in the Algarve for themselves and
their three children aged 3, 4 and 7 years. They say that they expect their
meals will be a mixture of self-catering and meals out. What advice, if any,
would you give them to help prevent diarrhoea?
Please write your answer below
Cholera
This is a diarrhoeal illness, indistinguishable from other cases of travellers’
diarrhoea. Spread by contaminated water and food, rarely present if hygienic
eating and drinking advice is followed.
Typhoid
Like cholera, typhoid is a water- and food-borne illness that causes diarrhoea.
Typhoid immunisation is recommended for travellers to countries where
sanitation standards are poor, but this is not a substitute for good hygiene.
The incidence of cholera and typhoid is similar to that of travellers’ diarrhoea.
It is higher among British travellers going to Africa or the Indian sub-continent
than in those going to the Mediterranean, but no travel is without risk.
Hepatitis
Of the five hepatitis viruses, A, B, C, D and E, only A is spread by food and
water. The rest are spread via blood and other body fluids.
Hepatitis A occurs in all countries with poor sanitation and public hygiene. It is
rare in Western Europe, Scandinavia, North America, Japan, New Zealand
and Australia. Most cases imported into Britain are contracted in the Indian
subcontinent (India, Pakistan, Bangladesh and Nepal) where the density of
the population and poor sanitation combine to make the disease common
(TRAVAX) Strict attention should be paid to food and water hygiene and
travellers to developing countries should be vaccinated.
Active vaccination gives very effective and long-term protection against
hepatitis A. It can be given from one year of age. Those with a history of
jaundice or who have lived for a long time in endemic areas may have
become “naturally” immune as a result of infection. Their blood can be tested
for hepatitis A IgG antibodies and vaccination is not necessary if these
antibodies are present (TRAVAX).
Note that the Hepatitis A immunoglobulin used for protection against hepatitis
A is prepared from pooled blood donations, unlike “specific immunoglobulins”
(rabies, tetanus, hepatitis B etc) which are prepared from the blood of
specially vaccinated donors. In countries where hepatitis A is now very rare
pooled immunoglobulin from blood donors may no longer contain sufficient
hepatitis A antibodies to give protection so the product has to be imported.
Hepatitis immunoglobulin is administered intramuscularly, however, there is
now evidence that active vaccination gives good protection against illness
8
even if administered shortly before or immediately after exposure – so
immunoglobulin is now rarely indicated even for the protection of travellers
attending at the last minute. It can be occasionally be useful when active
vaccination may be ineffective (e.g. in the immunocompromised) or contraindicated (previous adverse reaction to vaccination).
Hepatitis B Hepatitis B virus (HBV) is highly endemic in South East Asia, the
Pacific regions and West Africa. It is common in South and Central America,
the Indian subcontinent and the Middle East. It is present but rare in most of
Europe, Australia and North America although there are pockets of infection in
these regions in certain groups such as Inuit, Aboriginal and Maori
populations (TRAVAX).
Avoid unsafe sex, and also injections and surgical procedures (that is, the use
of inadequately sterilised needles, syringes and surgical instruments) to avoid
catching Hepatitis B. There is a combined Hepatitis A and Hepatitis B vaccine
available for adults. Hepatitis B Vaccination is recommended for the following
specific categories of travellers.
Those going to medium and high risk areas and likely to be putting
themselves at risk through their intended lifestyle – for example, volunteers
undertaking activities such as construction work which may result in bleeding
skin injuries and military personnel.
All frequent travellers to these areas and those staying for longer periods, that
is, more than 1 month.
Those who may be exposed to blood or blood products through their
occupation or life style such as health care workers and ambulance crews and
those likely to take sexual risks or use intravenous drugs.
Young children mixing with locals in schools where cuts and scratches are
common or living in poor hygienic conditions.
Those with pre-existing medical conditions who may need medical attention or
surgical procedures while abroad, such as women who may be pregnant or
may become pregnant.
Serological testing after vaccination and the need for boosters
This has until recently been routinely performed for those at occupational risk
since it allowed non-responders to be identified and gives guidance on when
boosters may be required. Travellers were frequently not tested.
9
However, European Consensus Guidelines conclude that exposure to natural
infection after effective immunisation rapidly boosts antibody levels. Repeated
serological testing is therefore not considered necessary if the serological
HBsAb response (8-12 weeks after the 3rd dose) is at a satisfactory level.
This ideally is above 100 i/units per litre, although above 10 i/units per litre is
also considered satisfactory by most authorities. Some laboratories
recommend a 4th dose of vaccine if the initial response is between 10 and
100 i/units per litre but without any further boosters so long as the level
remains the same or above.
Note
Post vaccine antibody checks are not generally recommended for healthy
travellers with no underlying medical conditions.
A single booster dose 5 years following completion of their course may be
given if they remain in an “at risk” travel category e.g. regular traveller to
areas with poor health care and high incidence of hepatitis B carrier rate.
They would also be advised to have a booster if in an at risk situation e.g.
needle stick injury.
Any traveller with an underlying medical condition that may compromise their
response to vaccine should consider serology testing. These travellers should
seek testing 8-12 weeks after the primary course has been completed. i.e.
after 3 doses except for the rapid schedules (2 month or 3 weeks schedules)
when it will be after the 4th dose at one year. If serology is adequate, then a
booster at five years is unnecessary. 10
Unfortunately a small proportion (5-10 per cent of healthy individuals) fail to
achieve an adequate antibody response following vaccination. These “nonresponders” will therefore remain at risk and travellers should be aware of the
potential for this, ensuring that they take precaution measures against blood
borne viruses at all times when travelling.
Poliomyelitis
This disease is spread by food or drink contaminated with faeces or in mucus
from the nose and throat. It starts with non-specific symptoms, such as
headache, muscle pains and stiff neck, and over the next 24 hours paralysis,
which may be limited to a single limb or may extend over most of the body.
Good hygiene helps to reduce risk but is no substitute for immunisation.
Poliomyelitis eradication policies are in place throughout the world, and the
disease occurs only when these policies break down. Cases are reported
occasionally from Africa and parts of south-east Asia.
Malaria
Malaria is the single most important insect-borne disease facing travellers to
most tropical countries. Malaria is now predominantly a disease affecting
Africa, South and Central America, Asia and the Middle East. (TRAVAX).
Malaria is a protozoan infection transmitted by mosquitoes biting mostly
between sunset and sunrise. The risk of malaria is becoming increasingly
serious. Treatment and prevention of malaria is becoming increasingly difficult
because resistance to anti-malarial drugs is increasing. Protection against
malaria is best achieved by the following:
Being aware of the risk
Avoiding being bitten
Taking chemoprophylaxis where appropriate
Seeking early diagnosis and treatment
Symptoms of the disease include fever, malaise, headache, abdominal pains
and chills with sweating. Jaundice and coma can sometimes develop rapidly.
The incubation period following a mosquito bite is at least five days, but can
be as long as one year, particularly if antimalarial drugs have been used.
Prevention of malaria
There is no immediate prospect of an effective vaccine for malaria. Animal
and human studies have shown the feasibility of vaccines targeted against
different stages of the development of the parasite, but both natural and
vaccine-induced immunity are hampered by the ability of the parasite to
change the structure of its antigens.
The most important means of malaria prevention is for individuals to protect
themselves from being bitten. Drug prophylaxis is important, but you need to
remind travellers that drugs offer relative – not absolute – protection.
Insect repellents
A safe and effective insect repellent is essential. Repellents act as masks
reducing the insects’ attraction to the skin. Insect repellents should be applied
to exposed areas of the skin, especially between the hours of dusk and dawn,
which is when malaria mosquitoes commonly bite.
The most effective and widely used repellent is
N. N, -diethyl -m- toluamide (DEET), either alone or in a combination with
ethohexadiol or ethylhexanediol and dimethyl phthalate (DMP). Both DEET
and DMP have a long history of use and both appear to be safe and effective
when used according to manufacturers’ instructions.
Application should normally be repeated every three to four hours (depending
on strength (20 to 100%) especially in hot and humid climates. It is important
to emphasise this as travellers may skimp on the use of repellents
(particularly DEET) because they can be quite costly. Note - when DEET and
sunscreen are used together, DEET should be applied after sunscreen
DEET is also fairly unpleasant to use. It has a powerful musty smell and can
cause skin irritation in some people. Put in perspective though, DEET is used
regularly by millions of people every year with no ill effects.
Various natural ingredients are also used in insect repellents. Examples
include oil of citronella and lemon eucalyptus oil. In addition, permethrin can
be recommended as extra protection – to be applied to the clothing and
mosquito nets. It is important not to frequently wash clothing that is
impregnated, as the effectiveness will be reduced.
Chemoprophylaxis
Most developed countries have national guidelines for malaria prophylaxis. If
possible chemoprophylaxis is best prescribed or sold within a month before
travel.
Concordance
Concordance with an antimalarial regimen is a problem for many travellers,
and the importance of this should be emphasised. The tablets must be taken
regularly without fail.
Several drugs are used for prophylaxis and various issues are pertinent to
each one. The presence of chloroquine susceptible and chloroquine resistant
Plasmodium Falciparum should be determined as this influences the choice of
anti malarial medication. Patient factors such as pregnancy and epilepsy will
also influence choice of medication.
Chloroquine - Once the drug of choice for malaria prophylaxis, chloroquine’s
usefulness is now limited to certain areas. It should be taken with food as
adverse reactions include nausea, vomiting and a bad taste. It can cause
flare-ups of psoriasis so is not recommended for these patients and prolonged
use may result in corneal and retinal changes. The drug should be changed
when a total of 100g has been taken. Blurred vision may also occur and an
eye examination may be appropriate. Chloroquine has occasionally been
linked to causing seizures so should not normally be used in those with
epilepsy or when first degree relatives have idiopathic epilepsy
Proguanil- This is used in combination with chloroquine for prophylaxis
against chloroquine resistant Plasmodium falciparum and is thought to be 6585 per cent more effective than chloroquine alone. Compliance can be a
problem with this regimen because of the need to combine a weekly and daily
medication. Side-effects are infrequent and include nausea, diarrhoea and
mouth ulcers. Proguanil is an antifolate drug but rarely produces problems in
the recommended doses. If taken in pregnancy 5mg of folic acid daily is
recommended. If taken for long periods (more than one year) it may cause
alopecia.
11
Doxycycline - This is a possible alternative for the prevention of malaria for
those travelling to areas of mefloquine or multiple-drug resistant Plasmodium
falciparum, and for those intolerant to mefloquine. However, it is not licensed
for this purpose and is not very effective against P vivax. Side effects include
gastrointestinal problems, fungal infections and photosensitivity (sunscreens
are important). It is contraindicated in pregnant women and children.
Malarone - Licensed for stays in malarious areas for periods of up to 28 days
but can be used safely for up to 3 months (and possibly 6 months or longer).
Specialist advice should be sought for long-term prophylaxis (TRAVAX).
Mefloquine - A great deal of controversy surrounds the use of mefloquine.
Available to travellers from Europe since 1985, it is recommended for travel to
areas where there is chloroquine resistance (for example, East Africa).
Following much media coverage of the neuropsychiatric and other side effects
(for example, nausea and dizziness) of this drug the public is concerned about
its safety. Individuals should be advised about potential side effects and if
these are severe enough to warrant withdrawal the person should seek
medical advice about alternatives. Mefloquine, like chloroquine, is
contraindicated in patients with a history of convulsions.
Risk of contracting malaria varies greatly from country to country. The
greatest risks occur in sub-Saharan Africa, Central and South America, South
East and East Asia and the Pacific Islands.
You should remember that malaria protection consists of following the ABCD
rule:
A - Be Aware of the risk of malaria
B - Prevent or avoid Bites from the
infected mosquito
C - Comply with the appropriate
Chemoprophylactic drugs
(preventative medication)
D - Prompt Diagnosis following
any symptoms of malaria
(e.g. flu-like symptoms) and obtain treatment immediately
Exercise 4
Two young men appear in your pharmacy. They are planning to travel through
Thailand and Cambodia. The last minute nature of their travel queries
indicates a casual attitude to health and you realise that you need to make
firm recommendations to them about mosquito and insect bite protection.
What general advice would you give them?
Please write your answer below.
SUMMARY
Diarrhoea is the most common condition in travellers, but much can be done
to prevent it in terms of strict hygienic procedures with food and water.
Rehydration is the most important aspect of treatment and the use of
antibiotics somewhat controversial. Other food – and water-borne conditions
include cholera, typhoid and hepatitis. The risk of all three can be reduced by
attention to food hygiene, and in addition, immunisation against typhoid and
hepatitis A is recommended for travellers to tropical countries. Protection
against hepatitis B is best achieved by avoidance of unsafe sex and
avoidance of inadequately sterilised needles and surgical instruments.
Travellers should carry a kit containing sterile needles and syringes.
The incidence of malaria is increasing worldwide and 2000 cases are
imported into the UK each year.
You have an essential role in advising travellers on the importance of
protecting themselves against insect bites and on the importance of
compliance with chemoprophylaxis. Protection against insect bites is equally
important to prevent other insect-borne diseases such as yellow fever and
dengue. Travellers should also be counselled on the risks of over exposure to
the sun and measures to protect against sun burn
Travellers should also be advises on vaccinations. Preparation for vaccination
and malaria prophylaxis should be undertaken in plenty of time – in the case
of vaccination, up to two months in advance.
Reflection Box
Please write your answer below each question.
Could I provide travel health services to my patients?
What training needs do I have to deliver these services?
How can I address these training issues?
ANSWERS TO EXERCISES
Exercise 1
The patient could be advised to try the following. Elasticated wrist bands are
available. These apply firm pressure to a defined point on the inside of the
wrists (a Chinese acupuncture point). There is no consistent evidence of their
effectiveness, but they have no side effects and do have to be remembered
beforehand. Anecdotally they seem to work well in children. Drivers and
pregnant women could also be advised to try them.
Ginger has also been reported to reduce motion sickness and it is included in
some preparations. Again, there is no sound scientific evidence that it works,
but it may be worth trying in drivers and pregnant women.
Exercise 2
To reduce the risk of sun damage, the following advice is important:

Avoid the midday sun (11am till 3pm).

Seek natural shade as much as possible.

Wear a wide-brimmed hat, sunglasses and suitable clothing as
protection (eg teeshirts allow the back of the neck to get burnt). Be
aware that sunglasses of different UV protection can be obtained.

Use a broad spectrum sunscreen with an SPF of 15 or higher,
providing both UVA and UVB protection.

Use of sunbeds to prepare for holidays should be discouraged and
children should not use them at all.

Patients taking photosensitising drugs eg doxycycline or amiodarone
should avoid the sun as much as possible.
Exercise 3
Water should only be drunk when you are sure of its purity. Don’t drink it
without boiling, chemical disinfection or using a reliable filter. This also applies
to water used for making ice cubes and cleaning teeth. Bottled water is
usually safe, as are hot tea and coffee, beer and wine.
Milk should be boiled unless you are sure it has been pasteurised.
Cheeses and ice-cream are oflen make from unpasteurised milk and when in
doubt these should only be bought from larger well established companies
when quality can usually be assured.
Meat should be thoroughly cooked and eaten hot whenever possible Avoid
leftovers.
Fish and shellfish can be hazardous at certain times of year, even if well
cooked. Take local advice about seafood, but when in doubt it is best to avoid
them.
Vegetables should only be eaten when thoroughly cooked.
Green
salads
should
be
avoided.
Fruit should be peeled, including tomatoes.
Wash hands thoroughly before eating or handling food, and always after using
the toilet.
Exercise 4
Apply an insect repellent to all exposed areas of skin. Wear long sleeves and
trousers outside, especially after dusk. Use a mosquito net over the bed. Use
anti-mosquito sprays or dispensers containing pyrethroids or burn mosquito
coils in the bedroom at night. Stay whenever possible, in well constructed
buildings with screens over the doors and windows. If screens are not
available, doors and windows should be closed at sunset. Air conditioned
accommodation is generally safer, but this may be limited on an overland trip
in South East Asia. Impregnate clothing with insecticide.
References
All the websites listed below were current when checked before publication,
but you should expect that some of these may be amended, altered, or even
deleted over time.
1. http://www.fitfortravel.scot.nhs.uk, accessed August 2012
2. http://travax.nhs.uk/health-information, accessed August 2012
3. http://www.who.international travel and health, accessed August 2012
4. Philippe G, Gaudart J, Leder K, Schwartz E et al 2012. Travel
associated illness in older adults. Journal of Travel Medicine;19(3) :
169-177
5. Christenson John C. 2008. Preparing families with children travelling to
developing countries. Paediatric annals;37:806 -813
6. http://bestpractice.bmj.com, accessed August 2012
7. Hill, DR Beeching, NJ. Travellers Diarrhoea. Current opinion in
Infectious Disease 2010: 23;488
8. Sagliocca L, et al (1999) ‘Efficacy of hepatitis A vaccine in prevention
of secondary hepatitis A infection: a randomised trial’ Lancet; 353:
1136-9.
9. European consensus group on hepatitis B immunity. (2000) ‘Are
booster immunisations needed for lifelong hepatitis B immunity?’
Lancet; 355:561-65
10. Salsibury D, Ramsay, M. Immunisation against infectious disease (The
Green book). The stationery office, London, 2006.
http://www.dh.gov.uk/enPublicationsandstatistics/PublicationsPolicy
and Guidance /DH - 079917
11. Chiodini P, Hill D. Guidelines for malaria prevention in travellers from
the UK 2007. Health Protection Agency; 2007