What vaccines do you need for travel?
If you travel outside Australia, you may get sick from a number of diseases that are preventable by vaccination.
Different vaccines are needed for certain countries. There is no standard immunisation schedule that will suit all travellers. The recommended vaccines for travelling depend on a number of factors. These include your age, pregnancy or planning pregnancy, underlying medical conditions, vaccination history, location and season of travel.
When should you get vaccinated?
You should consult your doctor or visit a travel health clinic six to 12 weeks before you leave Australia.
It is important that you don’t wait until the last minute to visit your doctor to discuss what vaccines you need for your trip. You might need a number of doses of a particular vaccine and you might need time after immunisation for your body to develop full immunity.
Infections acquired by travellers
Exposure to infectious diseases, some of which are vaccine preventable, is one of the many health hazards of international travel. Although some of these diseases are present in Australia, the risk of acquiring them overseas may be higher because of higher disease incidence in other countries and/or increased risk of exposure resulting from activities undertaken during the travel period.
Common infections acquired by travellers include those that follow ingestion of contaminated food or beverages. Most of these are diarrhoeal diseases due to enteric pathogens, but infections with extra-intestinal manifestations, such as hepatitis A and typhoid, are also acquired this way. Vaccines against hepatitis A, typhoid and cholera are available.
Insect-borne (particularly mosquito-borne) infections, such as malaria and dengue, are important causes of fever in Australian travellers returning from endemic areas, particularly Southeast Asia and Oceania. Japanese encephalitis occurs throughout a large part of Asia and the Western Pacific region, including eastern Indonesia and Papua New Guinea. Yellow fever occurs only in parts of Africa and South America, while tick-borne encephalitis occurs in parts of Europe and Asia. Vaccines are available for protection against Japanese encephalitis, yellow fever and tick-borne encephalitis.
Vaccine-preventable infections transmitted via aerosols and/or droplets include influenza, meningococcal disease, measles, mumps and varicella (chickenpox); influenza is typically the most frequent vaccine-preventable infection among travellers.6 Incidences of measles and mumps are higher in many overseas countries, including some developed countries, than in Australia. Tuberculosis is a rare infection in travellers and is more likely to be acquired by expatriates who live in endemic areas for long periods than by short-term visitors.
Blood-borne and sexually transmitted infections, such as hepatitis B, hepatitis C and human immunodeficiency virus (HIV), may pose a threat to some Australian travellers. In some areas, there is the possibility that these viruses and other blood-borne agents may be transmitted by healthcare workers using non-sterile medical equipment or other poor infection control practices. Hepatitis B vaccine is relevant to many travellers.
Travellers may be exposed to a variety of other exotic infectious agents, such as rabies (from bites or scratches from rabid dogs and other mammals in many countries), schistosomiasis (from exposure to water infested with the parasites, in Africa in particular), and leptospirosis (through activities like rafting or wading in contaminated streams). Of these, only rabies can be prevented by vaccination.
Some other vector-borne diseases and parasitic (including protozoal and helminthic) diseases are also important for international travellers, some of which are preventable through appropriate barrier precautions and chemoprophylaxis (e.g. malaria)
Diphtheria, tetanus and pertussis
Adult travellers should be adequately protected against tetanus before departure, particularly if their risk of sustaining tetanus-prone wounds is high or there could be delays in accessing health services where they can receive tetanus toxoid boosters safely if required. Protection against pertussis should also be offered at this opportunity (as dTpa) if no previous dose of dTpa has been given. Before departure, adults should be given a booster dose of dT, if more than 10 years have elapsed since the last dose, or dTpa if not given previously. For high-risk trips, consider giving a booster of either dTpa or dT if more than 5 years have elapsed
Hepatitis B
Most Australian children born since 2000, and a high proportion of adolescents, will have been vaccinated against hepatitis B under the NIP or jurisdictional school-based vaccination programs. Long-term or frequent travellers to regions of intermediate or high endemicity of hepatitis B, including Central and South America, Africa, Asia or Oceania, are recommended to be vaccinated against hepatitis B, due to the potential for inadvertent exposure to hepatitis B virus through blood-borne or sexual routes, including unplanned medical or dental procedures. A survey has shown that about half of Australian travellers who spent at least 3 nights in Southeast or East Asia had participated in at least one activity with a risk of acquiring hepatitis B.
Influenza and pneumococcal disease
Older travellers (usually those aged ≥65 years) and those with any relevant underlying medical or behavioural risk factors should receive the seasonal influenza vaccine and/or should have received the 23-valent pneumococcal polysaccharide vaccine. All travellers should consider influenza vaccine, especially if travelling during the influenza season of the destination region(s). The influenza vaccine is particularly relevant if influenza epidemics are occurring at the traveller’s destination(s), and for travellers in large tourist groups, especially those that include older persons, or travelling on cruises, where they are likely to be in confined circumstances for days to weeks.
Measles, mumps, rubella and varicella
Most measles outbreaks in Australia now result from an infection imported by inadequately vaccinated young travellers. Incidences of measles and mumps are higher in some overseas countries, regions or communities, including developed countries, than in Australia. Australians born during or since 1966 who have not received 2 doses of measles-, mumps- and rubella-containing vaccines should be vaccinated with the MMR vaccine before travelling.Varicella vaccine should be offered to unvaccinated travellers who have not had clinical disease, or where serology demonstrates lack of immunity in those with an uncertain history of clinical disease
Meningococcal disease
A single dose of MenCCV-containing vaccine is recommended for all children at the age of 12 months. This can be provided as either the combination vaccine Hib-MenCCV or MenCCV. Vaccination against meningococcal serogroup B is recommended for certain age groups who are at increased risk of meningococcal disease
Poliomyelitis
All travellers should be age-appropriately immunised against polio . If travelling to countries where wild poliovirus transmission still occurs, inactivated poliomyelitis vaccine (IPV) should be offered to those who have not completed a 3-dose primary course of any polio vaccine, and a single booster dose should be given to those who have previously completed the primary course. An up-to-date list of polio-affected countries is available from the World Health Organization (WHO) Global Polio Eradication Initiative website. Documented evidence of polio vaccination is not routinely required for travellers under International Health Regulations but may be temporarily recommended in accordance with WHO recommendations in response to new evidence of the spread of wild poliovirus. As international polio epidemiology and any associated travel requirements are subject to change, current recommendations for Australian travellers should be sought from the Australian Government Department of Health website.
Cholera
Cholera vaccination is rarely indicated for most travellers,8 as the risk of acquiring cholera for travellers in general is very low, provided that general precautions to avoid contaminated food and water are taken. The protective efficacy against Vibrio cholerae O1 is high (>80%) among children aged 2–5 years for the initial 4–6 months after 3 doses, but wanes to become insignificant afterwards. For those aged >5 years, protective efficacy is about 78% and 63% for the 1st and 2nd year, respectively, and wanes to become insignificant beyond 2 years after vaccination.9 The vaccine does not protect against the V. cholerae O139 serogroup. It is only indicated for those travellers at considerable risk, such as those working in humanitarian disaster situations. However, since cholera and enterotoxigenic Escherichia coli (ETEC) share the same toxin, cholera vaccination does afford some partial short-term protection against ETEC-caused travellers’ diarrhoea. The effect lasts only about 3 months, and the overall reduction of travellers’ diarrhoea risk would be less than 15%;10 however, there may be some travellers who would benefit from improved protection against travellers’ diarrhoea, including those with achlorhydria and those at increased risk of severe or complicated diarrhoeal disease.
Certification of cholera vaccination has been abandoned globally, and no countries have official entry requirements for cholera vaccination.
Hepatitis A
Hepatitis A vaccine should be recommended to all travellers ≥1 year of age travelling to moderately or highly endemic countries (including all developing countries), except those who are likely to have acquired natural immunity following previous infection. There is no longer any place for the routine use of normal human immunoglobulin to prevent hepatitis A in travellers
Japanese encephalitis
Vaccination is recommended for travellers spending a month or more in endemic areas in Asia and Papua New Guinea during the JE virus transmission season and should be considered for shorter-term travellers, particularly if travel is during the wet season or anticipated to be repeated, and/or there is considerable outdoor activity and/or staying in accommodation without air conditioning, screens or bed nets
Updated information regarding JE virus activity should be sought from a reputable source prior to travel (for example, Health information for international travel [the ‘Yellow book’] published by the US Centre’s for Disease Control and Prevention, available at (www.cdc.gov/travel/yellowbook).11 While the overall risk of JE in travellers to JE endemic countries is likely to be low (<1 case per 1 million travellers), the risk is determined by the season of travel, the regions visited, the duration of travel, the extent of outdoor activity and the extent to which mosquito avoidance measures are taken.
Meningococcal disease
Up-to-date epidemiological information should be sought to determine the need for meningococcal vaccination in travellers. Quadrivalent meningococcal vaccine (which includes serogroups A, C, W135 and Y antigens) is recommended for those who intend travelling to parts of the world where epidemics of meningococcal disease occur, in particular the ‘meningitis belt’ of sub-Saharan Africa. The Saudi Arabian authorities require that all pilgrims travelling to Mecca (for the Hajj or Umra) have evidence of recent vaccination with the quadrivalent meningococcal vaccine8 . The quadrivalent meningococcal conjugate vaccine should be used in preference to the quadrivalent meningococcal polysaccharide vaccine.
Rabies
Travellers to rabies-endemic regions should be advised of the risk of rabies infection, and to avoid close contact with either wild, stray or domestic animals, in particular dogs, cats, monkeys and bats. Travellers should also be aware of the importance of appropriate immediate wound care of all animal bites and scratches
Recommendation for pre-travel (i.e. pre-exposure prophylaxis) rabies vaccination (or, where indicated, booster doses) is based on an assessment of the likelihood of contact and risk of exposure to potentially rabid animals, the access to appropriate healthcare and availability of post-exposure prophylaxis, including rabies immunoglobulin, should there be an at-risk exposure, and the timeliness of such access after exposure. The previous recommendation for pre-exposure prophylaxis based on duration of stay in rabies-endemic areas (i.e. for more than a month) is arbitrary, and most Australian travellers who have required post-exposure prophylaxis have undertaken shorter periods of travel. A lower threshold for recommending rabies pre-exposure prophylaxis should be adopted for children travelling to endemic areas. Vaccination against rabies before travel ensures that a safe and efficacious vaccine has been used and simplifies the management of a subsequent exposure because fewer doses of vaccine are needed. It also means that rabies immunoglobulin, which is often extremely expensive, difficult or even impossible to obtain in many developing countries, is not required, and reduces the urgency of post-exposure prophylaxis.
Tick-borne encephalitis
Tick-borne encephalitis (TBE) is caused by a tick-borne RNA flavivirus and may involve the central nervous system. The disease is prevalent in parts of temperate regions of central and northern Europe and across northern Asia. Travellers are at particular risk when hiking or camping in forested areas in endemic regions during the summer months. Safe and effective vaccines are available. Vaccination is recommended only for individuals with a high risk of exposure. Two inactivated TBE vaccine formulations (from Austria and Germany) are available in Europe (based on the European subtype), and two other formulations, based on the Far Eastern subtypes, are available in Russia. There is limited evidence that suggests the Austrian and German vaccines induce cross-protecting immunity against the Far Eastern and Siberian subtypes. While the conventional schedule for completing the primary vaccination course takes 9 to 12 months, accelerated schedules are available While no TBE vaccine is registered in Australia, a small stock of vaccine may be available in Australia for use under the Special Access Scheme.
Tuberculosis
Vaccination with BCG vaccine is generally recommended for tuberculin-negative children <5 years of age who will be staying or living in countries with a high prevalence of tuberculosis for an extended period. There is less evidence of the benefit of vaccination in older children and adults, although consideration should be given to vaccination of tuberculin-negative children ≥5 years but <16 years of age who may be living or travelling for long periods in high-risk countries (defined as having an incidence >40 per 100 000 population)
For travellers who would require the BCG vaccine, the following precautions need to be considered when scheduling their vaccination visits:
Typhoid
Typhoid vaccine may be recommended to travellers ≥2 years of age travelling to endemic regions, including the Indian subcontinent, most Southeast Asian countries and several South Pacific nations, including Papua New Guinea. This advice is also relevant for those travelling (back) to endemic regions to visit friends and relatives (VFR travel). Inactivated parenteral or live oral typhoid vaccine formulations are available
Yellow fever
The yellow fever vaccine is recommended for all persons ≥9 months of age travelling to, or living in, an area with a risk of yellow fever virus transmission. To minimise the risk of yellow fever introduction, some countries require documented evidence of yellow fever vaccination for entry, in accordance with the International Health Regulations.
The risk of being infected with the yellow fever virus, country entry requirements, and individual factors like age, pregnancy and underlying medical conditions must be taken into account when considering yellow fever vaccination. Vaccination is generally not recommended when travelling to areas where there is low potential for yellow fever virus exposure (i.e. no human yellow fever cases ever reported and evidence to suggest only low levels of yellow fever virus transmission in the past). However, vaccination might be considered for a small subset of travellers to these areas who are at increased risk of exposure to mosquitoes or unable to avoid mosquito bites. People aged ≥60 years re at increased risk of severe adverse events after primary yellow fever vaccination. Vaccination of persons in this age group should be weighed against the potential for yellow fever virus exposure and, in turn, the benefits of vaccination
In most individuals, a booster dose is not required as a single dose of yellow fever vaccine induces protective antibody levels that persist for many decades. However, there are certain individuals for whom a booster is recommended if 10 years have passed since their last dose and they are at ongoing risk of yellow fever infection.