Travel Vaccinations

 

Introduction

This factsheet is designed for those planning to travel abroad who wish to know more about the common types of travel vaccines and their effects. It gives specific details regarding the most frequently needed vaccinations: Diphtheria; Hepatitis A and B; Japanese Encephalitis; Meningitis A and C; Rabies; Tetanus; Tuberculosis; Typhoid; Yellow fever. Further AXA PPP healthcare factsheets on immunisations specifically for childhood diseases are also available.

Vaccination and travel advice regarding specific countries change frequently, and up to the minute information can be obtained by contacting some of the organisations listed at the end of the factsheet.

What is a vaccination?

The word vaccination is derived from the Latin "Vacca", meaning cow. Vaccinations were developed by Edward Jenner in 1796, who noticed that milkmaids who caught cowpox, never caught smallpox. By inoculating a boy with cowpox and later testing his resistance to smallpox, Jenner developed the first practical ideas on the body's defence against disease (immunity).

How do vaccines work?

Vaccines offer two types of immunity: active and passive.

Active immunity

Active immunity is where the body is stimulated to make its own antibodies. These types of active vaccine stimulate the body's defence mechanism (the immune system) to make defence chemicals (antibodies), which stay in the body for a period of time. Whilst the antibodies to a particular disease are present, the body is protected from infection. The protection offered by these types of vaccine naturally take time to develop, but it does last a long time.

The principle of vaccination is the same in each of the three types of vaccine listed below:

  • Live attenuated vaccine
    These are vaccines where an organism has been treated to reduce the ability to cause disease itself. A single dose usually produces immunity and lasts a long time, but not always as long as the immunity which follows actually having the disease.
  • Inactivated vaccine
    A preparation of killed organisms. These often require an initial course of injections to produce immunity, and most of them need booster (reinforcing) injections to maintain immunity. The duration of the immunity varies between different vaccines from a few months to many years.
  • Detoxified exotoxins
    Fragments of, or a safe preparation of, the poisonous substances made by some organisms. They are also known as fragments of exotoxins. These require an initial course and regular boosters to maintain immunity.

Passive immunity

Passive immunity on the other hand gives immediate protection. It does this because, rather than stimulating the body into forming antibodies to an infection (which is what active immunity does), passive immunity involves injecting the body with antibodies that have already been made. This has the advantage that the antibodies can go to work defending the body straight away (whereas active immunity involves a delay whilst the body makes its own antibodies) but has the disadvantage that the protection it offers is usually quite short lasting when compared to active immunity. For instance Hepatitis A immunoglobulin vaccine (which is a form of passive immunity to Hepatitis A) will act immediately but is unlikely to work for longer than three months. So, anyone needing protection for longer than this is advised to have the Hepatitis A vaccine which gives protection for 10 years if the full course of two injections is given.

 

Why are vaccinations necessary?

The diseases for which immunisation are available are all dangerous and carry considerable risks. Although catching the disease would give immunity, it would be a highly unpleasant experience even if recovery were straightforward. Every vaccination has some side effects and risks, but these are much less than those of the disease. In general, the benefits of immunisation far outweigh the risks.

How are vaccinations carried out?

Most immunisations are given by injection into the skin (intradermally), just below the skin or into the muscle (intramuscularly). They are administered to different parts of the body, depending on the vaccine. The choice of injection site is made with the aim of maximising the effective absorption of the vaccine and to minimise any adverse reaction. Some other vaccines, such as oral polio, are given by mouth as drops. The specific methods of administration for some common travel vaccines are detailed below.

What are the general side effects?

Some vaccines (eg. polio) produce very few reactions, whilst others (eg. measles and rubella) may produce a very mild form of the disease. Some vaccines may produce a moderate discomfort at the injection site, together with a low fever and flu-like feeling of being mildly unwell. This usually lasts no more than 36 hours, and is a sign that the immune system is strongly stimulated.

Severe allergic reaction (anaphylaxis) can be dangerous, but fortunately is extremely rare. It is not possible to predict who may get this reaction, unless it has occurred previously. Details of specific reactions to common travel vaccines are also listed below. If these symptoms do persist then contact your GP.

 

When should vaccination be avoided?

In some situations vaccination should not be given (referred to as contraindications). In general, vaccination after an acute illness involving a temperature should be postponed until a full recovery is made. Minor infections without fever, or with the mildest symptoms only, are not a bar to vaccination. Also some vaccinations contain tiny quantities of antibiotics (neomycin and polymyxin) and they should not be given to individuals who are allergic to these antibiotics.

Anyone with a true severe egg allergy should not have yellow fever vaccination, as the vaccine contains small amounts of egg protein. Pregnant women should not receive live vaccines such as Yellow fever unless there is a significant risk of exposure, and the case for vaccination outweighs any possible risk to the mother and to the unborn baby.

Live vaccines should also not be given to anyone with a damaged immune system, whether caused by disease (eg. leukaemia, lymphoma) or by treatment (eg. chemotherapy, radiotherapy, and high-dose steroids). Special guidelines are also available for HIV-positive individuals, who may receive some live vaccines.

Anyone with a bleeding disorder (eg. haemophilia or thrombocytopneia) should avoid having injections into the muscle since this is liable to cause bleeding into the muscle.

What are the common types of travel vaccines? Diphtheria

Diphtheria

What is it and how is it given

This is a severe infection of the throat which can progress to a more serious illness as the bacteria causing it (called Corynebacterium diptheriae) produces a toxin (poison) which can affect the nerves of the body and the heart. It is spread by close contact with an infected person and is more common in areas of overcrowding and poor personal hygiene. It is now re emerging in parts of Russia. The vaccine is a preparation of the toxin and it is given as an injection. If it has not been received as part of childhood immunisations then the adult version is a course of three injections given four weeks apart. Immunity lasts ten years in adults.

Specific side effects and contraindications

Side effects are usually mild, and are the usual ones associated with injections in general; contraindications as per vaccines in general.

Hepatitis A

What it is and how it is given

Hepatitis A is a liver infection caused by a virus, and produces a severe jaundice and general illness. It is spread through poor personal hygiene and contaminated food and drink. The vaccine is an inactivated virus preparation, now available as a single-dose injection which gives 1 year's cover or, if a booster dose is given between 6 and 12 months after the first injection, 10 year's protection. It is recommended for visits abroad of more than three months.

More recently the Hepatitis A vaccine is given as a combined vaccination with typhoid rather than as a single vaccine.

Countries where Hepatitis A immunisation may be recommended include all underdeveloped countries especially those with poor sanitation.

For visits abroad of less than three months, the Hepatitis A immunoglobulin injection giving passive immunity may be recommended if it is felt that there is insufficient time (less than 2 weeks) for protection to be achieved with the usual active immunisation and the visit is for a relatively short time.

Specific side effects and contraindications

Side effects are usually mild, and are the usual ones associated with injections in general; contraindications as per vaccines in general.

Hepatitis B

What it is and how it is given

Hepatitis B is an infection of the liver caused by a virus that results in inflammation of the cells of the liver preventing them from functioning properly. The result is a severe condition that usually involves jaundice (yellowing of the skin) and general illness which may last for many weeks and which is occasionally fatal. It is spread through blood to blood contact eg. through unprotected intercourse with an infected person, through the use of unsterilised or poorly sterilised medical equipment, ear-piercing and tattoo needles, and sharing contaminated needles in drug misuse.

The vaccine is a preparation of inactivated virus given by injection as three doses. Boosters follow the first dose after one month and six months. A blood test is necessary to check that immunity has been achieved. The vaccine may take up to six months (or longer) to work, but immunity then lasts for 3 to 5 years.

Occasionally the passive form of immunisation with Hepatitis B immunoglobulin may be advised for short term immediate protection of those at especially high risk such as medical or nursing personnel going to work in high risk areas when there is either not enough time to give a course of active vaccine or when they have failed to respond to a previous course of the vaccine.

Countries where there is a high rate of Hepatitis B in the population include most of Sub Saharan Africa, parts of South America and the Far East including China, Indonesia and many South Pacific Islands.

Specific side effects and contraindications

There is occasional soreness and redness at the injection site. The vaccination should be postponed in those people who are suffering from an illness that includes a temperature.

Japanese B Encephalitis

What is it and how is it given

This is an illness which is spread by mosquito bites and which results in a headache, temperature, stiff neck and muscle twitching and which may result in coma and death. The disease occurs mainly in South East Asia but also occurs in India. The vaccine consists of three injections of inactivated virus with seven days between the first and second injection and then 21 days between the second and third, although there is a faster schedule for those people who need protection in a hurry, but this is not as reliable.

Side effects and contraindications

The most common side effect is an itchy or red rash, which can cover large areas of the body. This is usually treated with antihistamines. In some cases there may be joint or muscle pains and a temperature.

Meningitis A&C

What it is and how it is given

Meningitis is inflammation of the membranes covering the brain and spinal cord and can be caused by a number of types of infection. One of the more serious types of meningitis is caused by a bacterium called Neisseria meningitidis of which there are 3 main strains A, B and C.

Called Neisseria meningitis of which there are three main strains A, B and C.

It is droplet spread ie. in the air from an infected individual, and results in a serious illness which usually includes a temperature, severe headache, persistent vomiting, neck stiffness and a rash although a sufferer may not have all these symptoms. Severe cases can result in death. A type of meningitis C vaccine is now routinely given to children in the UK but vaccination against A and C is still recommended for travellers to certain parts of the world.

The vaccine consists of a single injection which gives three or five years' protection, depending on which form is given, except in children under two years' old who need a booster after a year to gain full protection. A vaccine for the B strain of meningitis is in the process of development.

Vaccination against meningitis is especially important for long term travellers to parts of Africa especially if they are going to live amongst the locals or come into close contact with them.

Specific side effects and contraindications

Local irritation at the site of the injection sometimes occurs but more severe reactions are rare.

Polio

What it is and how it is given

Polio (short for poliomyelitis) is an illness that affects mainly children and young adults and is caused by the poliovirus spread usually by poor hygiene. In most cases the resulting illness is a mild one lasting only a few days and causing no more than a slight temperature, sore throat, headache and vomiting. However, in some cases it may attack the brain and spinal cord resulting in paralysis which may be mild or severe but which is permanent. .

In the UK Polio has been virtually eliminated by the regular immunisation of babies. However it still exists in certain parts of the world, mainly those under developed countries such as Africa and Asia.

There are two types of vaccines for poliomyelitis:

The inactivated poliomyelitis vaccine by injection is now recommended for routine immunisation. Adults do not need booster doses except those who are at significant risk, such as travellers in endemic areas or those exposed to the viruses due to their occupation, eg laboratory worker. Such individuals will have booster doses every 10 years.

The other vaccine consists of drops of attenuated live polio taken by mouth on the tongue. The live vaccine is only being used during polio outbreaks.

Side effects and contraindications

There is a very small risk (between about 1 in half a million to 1 in 12 million) of developing polio after vaccination with the live polio vaccine. The vaccine should not be given when the patient is suffering from an acute illness, especially if it involves a temperature, vomiting or diarrhoea. Nor should the live vaccine be used for individuals who are immunosuppressed.

Rabies

What it is and how it is given

Rabies is an acute viral infection of the nervous system, which is spread through the bite of an infected animal and is usually fatal. The vaccine is an inactivated virus cultivated in human cells, given as a course, the second after one week and the third after four weeks. Protection lasts 2 - 3 years.

Rabies is present in all continents except Australasia but details of countries where rabies vaccine is recommended should be sought either from the travel clinic or from the information sources mentioned at the end of this factsheet.

Specific side effects and contraindications

Local skin reactions may occur at the site of the injection. It should not be injected into the muscles of the bottom (studies have shown that there is a poor response). Pregnancy is not considered a contraindication.

Tetanus

What it is and how it is given

Tetanus is a disease caused by the bacterium Clostridium tetani. The spores of the bacterium can survive in faeces, dust and soil, and grow actively within wounds, producing a poison, Tetanospasmin, which causes muscular spasms and stiffness. These can be so severe as to prevent breathing so the disease can be fatal.

The vaccine is routinely given as part of the childhood immunisation in the triple vaccine. A preparation of the fragment of the toxin (toxoid) is injected, stimulating the body to make an antitoxin. This creates a basic immunity that requires boosters at school entry and school leaving. Boosters of tetanus toxoid are only given every ten years twice thereafter as any adult who has received up to 5 doses is likely to have life-long immunity. A booster should also be given to anyone with a potentially contaminated wound who has gone longer than ten years since a booster. Any older person who has never had the initial course of three injections should ensure they obtain the full course.

Tetanus occurs worldwide (including the UK) so travel plans are often used as an opportunity to update someone's tetanus immunity

Specific side effects and contraindications

Local skin reactions at the site of the injection occasionally occur. More serious reactions are very rare. As with most vaccinations, it should not be given during an acute illness that involves a temperature.

Typhoid

What it is and how it is given

Typhoid is caused by a bacterium and produces severe, life-threatening diarrhoea. It is spread through poor personal hygiene and contaminated food and water and is common in many countries of the world but especially in those where food and water supplies are liable to mix with waste-water. This includes countries in Africa, the Far East and South America. There are three types of typhoid vaccine available:

  • Whole cell preparations
    The original typhoid vaccine is a preparation of whole but (dead organisms) given by injection, followed by a second (booster) dose given six weeks later. Three yearly boosters follow these. Though still available, it has been superseded, and the only medical advantage it offers over the newer vaccine is that it is effective in children between 12 and 18 months old, whereas the newer one is known to be less effective in children younger that 18 months. It is cheaper than its successor.
  • Part cell preparations
    A newer vaccine is a part cell preparation (ie. not whole organisms) given as a single injection followed by three yearly boosters on continued exposure. As only one injection is needed for the first three years of immunity, this is more popular than the original.
  • Live attenuated vaccine
    These are taken by mouth in three doses on alternate days. Protection starts 7-10 days after the last dose, and lasts about a year. Antibiotics and mefloquine, an antimalarial drug inactivates it. The course should ideally be completed three days before starting mefloquine. The timing and destination of travel may thus influence whether an injection or oral vaccine is recommended.

Specific side effects and contraindications

The injections are renowned as the ones more likely to cause side effects, which include local swelling and tenderness at the infection site, and fever and general malaise up to 36 hours after the injection. The oral typhoid vaccine is contraindicated in people with immune problems and is inactivated by antibiotics.

 

Tuberculosis (TB)

Tuberculosis is an illness which usually affects the lungs but which can affect many other parts of the body and, if untreated, is potentially fatal. It is most commonly spread through infected sputum but can also be contracted from unpasteurised milk. It occurs worldwide including in the UK where it is making a comeback, partly due to the development of resistance to treatment. In Britain an improved programme, of targeted vaccination for those individuals who are at greater risk, has replaced the universal BCG Vaccination programme that was delivered through schools.

Countries where TB is especially common include the whole of South America, Africa and places such as India and Indonesia.

Travellers going to countries where there is a high incidence of TB should check that they have been vaccinated if they are unsure of their vaccination status. If they are found not to be immune to TB they should be vaccinated, especially if they are going to be mixing closely with the local population and/or are visiting the country for longer than a month.

The vaccine consists of a single injection into the skin of live attenuated BCG vaccine and is effective from 6-8 weeks after administration.

Yellow fever

What it is and how it is given

This viral illness is caught from the bite of an infected mosquito, and causes severe general illness, causing muscle breakdown, sickness and fever. Sometimes it causes generalised bleeding. The vaccine is a single-dose injection of live attenuated virus cultured in chickens' eggs. Immunity lasts at least 10 years (officially accepted figure) but probably lasts for life and is only obtainable at specified Yellow fever vaccination centres, although these do include some GP surgeries.

Countries currently reporting Yellow fever include many African countries and several countries in South America. In addition, some countries require a certificate of Yellow fever vaccination in order to pass through them even if that country does not have Yellow fever itself. For details, consult the local travel clinic or the information sources listed below.

Specific side effects and contraindications

It should not be given to infants under nine months, pregnant women (unless at very high risk of the disease), and to those with immune deficiency or a history of severe egg allergy. In about 5-10% of people the vaccine causes a mild local skin reaction or slight feelings of being unwell. More severe reactions are very rare.

 

Where can I get further information?

Apart from contacting your GP, the following organisations may be of further help:

Hospital for Tropical Diseases
Mortimer Market
Capper Street
London
WC1 6AU
Travel Healthline Advisory Service: 09061 337733 (calls charged at 50p/min)
Appointments: 0207 388 9600

Malaria Reference Laboratory
09065 508908
(Calls cost £1 per minute)

MASTA Travel Clinics
52 Margaret Street
London
W1W 8SQ
Telephone: 0845 600 2236

National Travel Health Network and Centre
NATHNAC
Mortimer Market Centre
Capper Street
London
WC1E 6AU
E-mail: nathnac@uclh.nhs.uk
Website:www.nathnac.org

AXA PPP healthcare Health at Hand (for AXA PPP healthcare members)
Helpline: 0800 003 004