With increasing globalization, travel, and therefore novel exposure, is growing in the immunocompromised. An evaluation of the degree of immune compromise should be made. (Box 10.1).
Source: data from Kotton, C.N. et al. Advising Travelers With Specific Needs: Immunocompromised Traveler. In CDC Health Information for International Travel. Atlanta, USA: Oxford University Press & Centers for Disease Control and Prevention. Copyright © 2014 Centers for Disease Control and Prevention/OUP.
Appropriate pre-travel advice includes an assessment of the degree of compromise, intended destination and activities, vaccination, prophylaxis, access to medication, and appropriate medical care. Standard travel advice applies. General travel considerations are listed in Box 10.2.
Where indicated, immunization is vital to reducing the risk of disease in immunocompromised travellers. Inactivated or subunit vaccines are considered safe in all forms of immunocompromise. Additional booster vaccinations may be necessary with defective immune response. While the efficacy of the vaccine may be reduced (in terms of provoked immune response), they may be more effective as immunocompromised patients are more likely to suffer severe disease from infection. Live attenuated vaccines (e.g. BCG, MMR, oral polio vaccine, and yellow fever) have the potential to cause vaccine-associated disease and are therefore contraindicated in severe immunocompromise. All travellers should be up to date with routine vaccinations (unless contraindicated) in line with the latest national guidance.
UK guidance can be found at https://www.gov.uk/government/publications/the-complete-routine-immunisation-schedule.
This currently includes vaccination against diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b, hepatitis B, pneumococcus, rotavirus, meningitis B and ACWY (all inactivated or subunit), in addition to MMR (live attenuated).
Recommended in specific patient groups include annual influenza vaccination for children 2–8 years old, those >65 years old and chronic medical conditions (e.g. chronic renal failure, chronic liver failure, and diabetes), shingles vaccination in those >70 years old.
Up-to-date recommendations for travel vaccination can be found at:
• NICE Guidance: https://cks.nice.org.uk/immunizations-travel#!topicsummary.
• National Travel Health Network and Centre: http://www.travelhealthpro.org.uk/.
• Public Health England ‘The Green Book’ (2013) guidelines on immunization: https://www.gov.uk/government/publications/immunisation-against-infectious-disease-the-green-book-front-cover-and-contents-page.
Vaccinations considered safe in the immunocompromised
Diphtheria, tetanus, pertussis, H. influenzae type b, pneumococcus, hepatitis A, hepatitis B, meningococcal, rabies, inactivated typhoid vaccine, Japanese encephalitis, inactivated influenza, and inactivated polio.
Vaccinations contraindicated in the immunocompromised
The following vaccinations are contraindicated in severe immunocompromise and a consideration of the risks and benefits needs to be made in mild-to-moderate immunocompromise: BCG vaccine, oral live polio, MMR, herpes zoster, live oral typhoid vaccine, yellow fever, and live attenuated influenza vaccine.
Malaria prophylaxis is recommended for all immunocompromised patients travelling to areas where it is indicated. Up-to-date recommendations and risk assessments for specific geographic regions can be found at the National Travel Health Network and Centre website ( http://www.travelhealthpro.org.uk/).
The options are the same as for the non-immunocompromised: mefloquine, atovaquone/proguanil, doxycycline, and chloroquine and/or proguanil (in specific regions with little or no resistance). Interactions with concurrent medications should be checked. Bite avoidance and early presentation if unwell should be emphasized.
Travellers, both immunocompromised and not, remain susceptible to the usual infectious agents that cause respiratory, urinary, skin, GI infections etc. in human populations across the world.
Several organisms that are commonly associated with infection in the immunocompromised have a fairly ubiquitous global distribution (e.g. Pneumocystis pneumonia, CMV, Toxoplasma gondii, Cryptosporidium spp., Candida spp., Aspergillus spp., and Cryptococcus neoformans).
The following summary of geographical associations with specific infections omits pathogens that could be considered universal in all human populations, both immunocompromised and not. It is by no means exhaustive. Rather, it is designed to provide a broad idea of infections that may be relevant to immunocompromised travellers. In an age of modern air travel, it is becoming increasingly difficult to confidently determine firm geographical distributions for many infections.
Prophylaxis for specific infections beyond routine prophylaxis (e.g. malaria chemoprophylaxis) and specific recommendations for particular immunocompromised conditions (e.g. Pneumocystis pneumonia prophylaxis etc.) must be made on a case-by-case basis depending on the degree of immunocompromise, destination, and intended activities (e.g. antibiotic prophylaxis for traveller’s diarrhoea).
The unwell returning traveller
Key features of the history
• Degree of immune suppression: assess degree of compromise.
• Destination: exactly where has the patient been?
• Timing: incubation periods, duration of exposure, and season.
• Exposures: sexual exposure; activities (e.g. freshwater swimming, jungle trekking, etc.); insect bites, bed net use, etc.; sources of food, drinking water, etc.; healthcare contact abroad; animal bites; and air conditioning.
• Prophylaxis: malaria chemoprophylaxis, and vaccinations (consider efficacy in severe immunosuppression).
• Clinical syndrome: CNS, pulmonary, GI, fever with eosinophilia, rash, jaundice, fever and bleeding, etc.
The usual incubation periods for particular infections may be altered in the immunosuppressed patient. Box 10.3 shows incubation periods for common and important travel-related infections.
Malaria and HIV must be excluded in all unwell travellers returning from endemic areas. Consider the following conditions in addition to more usual causes:
Malaria, dengue, other arboviruses (e.g. chikungunya, zika), leptospirosis, typhoid and paratyphoid, rickettsial infection, tuberculosis, acute HIV infection, African and American trypanosomiasis, viral haemorrhagic fevers (Lassa, Ebola, Marburg), brucellosis, visceral leishmaniasis.
Fever with CNS signs
Malaria, bacterial meningitis (Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae), viral encephalitis (HSV, JEV, West Nile virus, enterovirus), leptospirosis, listeriosis, rickettsial infection, African trypanosomiasis, rabies and TB.
Fever with respiratory symptoms
Influenza, legionella, Middle East respiratory syndrome (MERS), SARS, melioidosis, TB, Q fever (Coxiella burnetii), pertussis, rickettsial infection, ascariasis (Loeffler’s syndrome), Katayama fever (acute schistosomiasis), meliodosis, histoplasmosis, and coccidioidomycosis.
Fever with gastrointestinal symptoms
E. coli (enterotoxigenic E. coli), Campylobacter spp., Salmonella spp., Shigella spp., amoebic dysentery (E. histolytica), hepatitis A virus, Cholera, Vibrio parahaemolyticus, Yersinia spp.
Fever with rash (often accompanied by thrombocytopenia)
Dengue, rickettsial infection, measles, Chikungunya, Zika, meningococcal infection and rubella.
Fever with jaundice
Viral hepatitis (HAV, HEV, acute HBV), leptospirosis, malaria, amoebic liver abscess and yellow fever.
Fever with eosinophilia
Alongside allergic reactions, classically associated with parasitic infections; nematodes (e.g. Strongyloides stercoralis), trematodes (schistosomiasis, flukes), filarial nematodes (e.g. lymphatic filariasis, onchocerciasis), cestodes (e.g. Taenia spp.). Myiasis (e.g. C. anthropophaga), scabies.
1. Kotton CN, Freedman DO. Advising travelers with specific needs: immunocompromised travelers. In: CDC Health Information for International Travel (‘The Yellow Book’). Centers for Disease Control and Prevention; 2014. https://wwwnc.cdc.gov/travel/yellowbook/2018/advising-travelers-with-specific-needs/immunocompromised-travelersFind this resource:
2. Public Health England. ‘The Green Book’ (2013) guidelines on immunization: https://www.gov.uk/government/publications/immunisation-against-infectious-disease-the-green-book-front-cover-and-contents-pageFind this resource: