CHOLERA

Cholera is an acute diarrhoeal disease caused by Vibrio cholerae bacteria.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Cholera is known or presumed to occur in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Cholera is transmitted through contaminated food and water. Most travellers are at low risk. Those at higher risk include humanitarian aid workers and travellers with remote itineraries in areas of cholera outbreaks, who have limited access to safe water and medical care.

Risk management

• Travellers should practice strict food, water and personal hygiene precautions.
• Vaccine should be givenAll travellers in risk categories should receive vaccine to travellers whose planned activities put them at a higher risk of exposure (see above).

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DIPHTHERIA

Pharyngeal or cutaneous diphtheria is caused by toxigenic strains of Corynebacterium diphtheriae bacteria and occasionally by C. ulcerans.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Diphtheria is known or presumed to occur in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Travellers may be exposed through the respiratory route, contact with infected objects, or exudate from an infected skin lesion. Those who will be in close contact with the local population are at higher risk.

Risk management

• Travellers should have completed a primary vaccination course according to the UK schedule.
• A booster dose of a diphtheria-containing vaccine should be givenAll travellers in risk categories should receive vaccine to those who have not received a dose within the previous 10 years.

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HEPATITIS A

Hepatitis A is a viral disease that causes inflammation of the liver.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Hepatitis A is known or presumed to occur in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Hepatitis A is transmitted through contaminated food and water. Those at higher risk include travellers visiting friends and relatives, long-term travellers, and those exposed to conditions of poor sanitation.

Risk management

• Travellers should practice strict food, water and personal hygiene precautions.
• Vaccine should be givenAll travellers in risk categories should receive vaccine to travellers whose planned activities put them at risk (see above).
• Because hepatitis A vaccine is well tolerated and affords long-lasting protection, it may be givenMost travellers at low risk, consider vaccine for those in risk categories to all previously unvaccinated travellers.
• According to UK immunisation guidance, in addition to its indications for travel, vaccine may be givenMost travellers at low risk, consider vaccine for those in risk categories to those with chronic liver disease or haemophilia, men who have sex with men, injecting drug users and those at occupational risk.

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HEPATITIS B

Hepatitis B is a viral disease that causes inflammation of the liver and may lead to chronic complications.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - 8% or more of the population in this country is a carrier of hepatitis B virus (high endemicity).
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Hepatitis B is transmitted via infected blood or bodily fluids. Travellers may be exposed when receiving medical or dental treatment, via direct contact between open skin lesions, or if participating in risk behaviour such as needle sharing, unprotected sex or contact sports. Healthcare workers are at higher risk.

Risk management

• Travellers should avoid contact with blood or bodily fluids. Where contact is unavoidable, appropriate protective precautions should be taken.
• A sterile medical kit should be carried.
• Vaccination should be considered for all adult and child travellers.
• Vaccination should be givenAll travellers in risk categories should receive vaccine to those at risk due to the nature of their activities or occupation (see above).
• Vaccine should also be givenAll travellers in risk categories should receive vaccine to those with chronic kidney failure, liver disease or haemophilia, injecting drug users, men who have sex with men and individuals who change sexual partners frequently.

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MENINGOCOCCAL MENINGITIS

Meningococcal meningitis is caused by one of the serotypes (A, B, C, W135, Y) of Neisseria meningitidis bacteria.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - This country lies within the meningitis belt of sub-Saharan Africa. View a map of countries in the meningitis belt here.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Transmission occurs via the respiratory route. Those at higher risk include healthcare workers, those visiting friends and relatives and long-term travellers who have close contact with the local population.

Risk management

• Travellers should avoid, if possible, overcrowded conditions.
• The quadrivalent vaccine (A, C, W135, Y) should be givenAll travellers in risk categories should receive vaccine to travellers whose planned activities put them at risk (see above).
• Previous vaccination with the meningitis C conjugate vaccine (MenC) does not protect against the other meningococcal serotypes.
• At present there is no available vaccine against serotype B in the UK.

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POLIO

Polio is a viral disease involving the gastrointestinal tract and occasionally the central nervous system, leading to paralytic poliomyelitis.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Poliomyelitis has been reported in this country since 2003.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Polio is transmitted through contaminated food and water. Those at higher risk of exposure include travellers visiting friends and relatives, those in direct contact with an infected person, long-term travellers, and those visiting areas of poor sanitation.

Risk management

• Travellers should practice strict food, water and personal hygiene precautions.
• Travellers should have completed a primary vaccination course according to the UK schedule. Previous poliomyelitis does not protect against another episode of poliomyelitis.
• A booster dose of a polio-containing vaccine should be givenAll travellers in risk categories should receive vaccine to those who have not received a dose within the previous 10 years.

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RABIES

Rabies is a neurological disease caused by viruses of the Lyssavirus genus.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Rabies occurs or is presumed to occur in wild and domestic animals (including bats).
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Transmission may occur following contact with the saliva from an infected wild or domestic animal (including bats), most often via a bite or lick to an open wound. Risk of exposure is increased by type of activity (e.g. running, cycling), occupation (e.g. veterinarians) and longer duration of stay. Children are at increased risk as they are less likely to avoid contact with animals and to report a bite or lick.

Risk management

• Travellers should avoid contact with wild or domestic animals.
• Pre-exposure vaccination should be givenAll travellers in risk categories should receive vaccine to adults and children who are:
  • at risk of rabies (see above)
  • travelling to remote areas where medical care is not readily available.
• Following an animal bite, wounds should be thoroughly cleansed and an urgent medical assessment sought, even if the wound appears trivial. Prompt post-exposure treatment is required, even if pre-exposure vaccine has been received.
• Suitable vaccines and immunoglobulin may be in short supply or unavailable in some countries.

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TETANUS

Tetanus is caused by a toxin released from Clostridium tetani bacteria.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Tetanus bacteria are found worldwide.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Tetanus bacteria are present in soil and manure and may be introduced through open wounds such as a puncture wound, burn or scratch.

Risk management

• Travellers should thoroughly clean all wounds and seek appropriate medical attention
• Travellers should have completed a primary vaccination course according to the UK schedule.
• A booster dose should be givenAll travellers in risk categories should receive vaccine to travellers whose last dose of a tetanus-containing vaccine was given more than 10 years ago, and who will not have ready access to medical care; even if they have received five doses previously.

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TUBERCULOSIS

Tuberculosis (TB) is caused by the bacteria Mycobacterium tuberculosis.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - The annual occurrence of TB was greater than or equal to 40 cases per 100,000 population in 2005.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - TB is transmitted following inhalation of infectious respiratory droplets. Most travellers are at low risk. Travellers at higher risk include healthcare workers, those who are visiting friends and relatives (particularly young children), long-term travellers, and those who have close contact with an infected individual. HIV-positive travellers and those with impaired immunity are also at higher risk.

Risk management

• The pre-travel visit is an opportunity to ensure that children in defined risk categories under 16 years of age are vaccinated with BCG according to current UK guidance (see resource below).
• Travellers should avoid close contact with individuals known to have infectious pulmonary TB.
• BCG vaccine should be considered for previously unvaccinated, tuberculin skin test negative individuals, under 16 years of age, who are going to live for more than 3 months in this country.
• Healthcare workers should take appropriate infection control precautions. BCG vaccine should be givenAll travellers in risk categories should receive vaccine to healthcare workers under 35 years of age. This recommendation is irrespective of duration of stay.
• There are specific contraindications (e.g. impaired immunity) and adverse events associated with BCG vaccine (see Green Book chapter in resources below). A careful risk assessment should be made before administration and specialist advice sought as appropriate.
• Travellers who are in the risk groups described and who do not receive BCG vaccine should be considered for pre-travel and post-travel testing for exposure to tuberculosis.
• Travellers who suspect that they may have been exposed to tuberculosis should receive an appropriate medical evaluation.

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TYPHOID

Typhoid fever is a systemic disease caused by Salmonella Typhi bacteria.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Typhoid fever is known or presumed to occur in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Typhoid is transmitted through contaminated food and water. Travellers who will have access to safe food and water are likely to be at low risk. Those at higher risk include travellers visiting friends and relatives, young children, long-term travellers, and those visiting areas of poor sanitation.

Risk management

• Travellers should practice strict food, water and personal hygiene precautions even if vaccinated.
• Most travellers are at low risk and do not need vaccination.
• Vaccine may be givenMost travellers at low risk, consider vaccine for those in risk categories to travellers whose planned activities put them at higher risk (see above). Current vaccines against Salmonella Typhi are only 50-80% protective and do not protect against Salmonella Paratyphi. Previous typhoid illness does not confer reliable immunity.

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MALARIA

Malaria is a serious febrile illness caused by infection of red blood cells with Plasmodium sp. parasites: P. falciparum, P. vivax, P. ovale and P. malariae. View a map of the global distribution of malaria as determined by the World Health Organization (WHO) here. Malaria prevention advice for this country follows the Health Protection Agency, Advisory Committee on Malaria Prevention (ACMP) guidelines.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country -
  • There is a high risk of malaria in Kenya.
  • There is very low risk in the city of Nairobi.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Malaria is transmitted via the bite of an infected Anopheles mosquito. Anopheles mosquitoes feed predominantly during the hours from dusk to dawn.

Risk management

• Awareness of risk - Risk depends on the specific location, season of travel, length of stay, activities and type of accommodation. Those at higher risk of malaria, or of severe complications from malaria, include pregnant women, infants and young children, the elderly, and those visiting friends and relatives.
• Bite prevention - Travellers should take mosquito bite avoidance measures. Anopheles mosquitoes feed predominantly during the hours from dusk to dawn.
• Chemoprophylaxis - No malaria prevention tablets are 100% effective. Taking malaria prevention tablets in combination with mosquito bite avoidance measures will give substantial protection against malaria.
  • Chloroquine resistance is widespread in Kenya and therefore the recommended chemoprophylaxis for malaria risk areas is mefloquine, doxycycline or atovaquone/proguanil (Malarone™).
  • Chemoprophylaxis is not recommended for travel only to Nairobi, however, travellers should be aware of the small risk of malaria.
• Diagnosis - Travellers who develop a fever of 38°C [100°F] or higher more than one week after being in a malaria risk area, or who develop any symptoms suggestive of malaria within a year of return should seek immediate medical care.

Health professionals may obtain advice on managing returned travellers with a suspected or confirmed diagnosis of malaria by consulting published guidelines:

• Advisory Committee on Malaria Prevention in UK Travellers (ACMP) Malaria Treatment Guidelines (Journal of Infection)
• British Infection Society Malaria Treatment Algorithm (548 KB PDF)

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ALTITUDE

There is a point of elevation in this country higher than 2,500 metres (m).

Risk assessment

• Travel to destinations of 2,500-3,500 m (8,200-11,500 feet) or higher carries the risk of altitude illness. Important risk factors for altitude illness are the altitude gained, rate of ascent and sleeping altitude. Rapid ascent without a period of acclimatisation puts a traveller at higher risk.

Risk management

• The most important prevention measure is adequate acclimatisation.
• Travellers should spend a few days at an intermediate altitude below 3,000 m.
• Ascent above 3,000 m should be gradual with no more than a 300 - 500 m increase in sleeping altitude per day, with a rest day every three days.
• Acetazolamide is recognised for use in the prevention of altitude illness. It should not replace acclimatisation and gradual ascent.
• Travellers who develop symptoms of altitude illness (headache, fatigue, loss of appetite, nausea and sleep disturbance) should avoid further ascent. In the absence of improvement or with progression of symptoms the first response should be to descend.
• Development of more severe forms of altitude illness, high-altitude cerebral oedema (HACE) (confusion, difficulty with balance and coordination) or high-altitude pulmonary oedema (HAPE) (shortness of breath at rest, cough and chest tightness), require immediate descent and emergency medical treatment.

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DENGUE FEVER

Dengue is a systemic viral disease. View a map showing the global areas at risk for dengue here (0.5MB PDF).

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Dengue is known or presumed to occur in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Dengue is transmitted via the bite of an infected Aedes aegypti mosquito. Aedes mosquitoes feed predominantly during daylight hours. All travellers to dengue areas are at risk.

Risk management

• Travellers should take mosquito bite avoidance measures. Aedes mosquitoes feed predominantly during daylight hours.
• There is no vaccination or medication to prevent dengue.
• A previous dengue illness with one of the four dengue virus serotypes does not confer immunity to other virus serotypes.
• Infection with a second dengue serotype may be a risk factor for the development of dengue haemorrhagic fever.

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SCHISTOSOMIASIS

Schistosomiasis is a parasitic flatworm infection of the intestinal or urinary system caused by one of several species of Schistosoma.

Risk assessment

• EpidemiologyInformation on the occurrence of disease within this country - Schistosoma mansoni (intestinal) and Schistosoma haematobium (urinary) are present in this country.
• ExposureInformation on the mode of transmission and factors that may increase disease risk - Schistosomiasis is transmitted through exposure to fresh water streams, rivers or lakes during activities such as wading, swimming, bathing or washing clothes. Schistosoma larvae are released from infected freshwater snails and penetrate intact skin to establish infection.  

Risk management

• Travellers should avoid wading, swimming, or bathing in fresh water.
• Swimming in chlorinated water or sea water is not a risk for schistosomiasis.
• Topical application of insect repellent before exposure to water, or towel drying after accidental exposure to schistosomiasis are not reliable in preventing infection.
• There is no vaccine or tablets to prevent schistosomiasis.
• Travellers who may have been exposed to schistosomiasis should have a medical assessment.

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