Essential Travel Vaccines for Southeast Asia: A Comprehensive Guide for Kiwi Travellers

Planning an adventure through Southeast Asia? From the bustling streets of Bangkok to the tranquil beaches of Bali, this vibrant region offers unforgettable experiences. However, protecting your health should be at the top of your travel checklist. This comprehensive guide covers the essential vaccines recommended for travel to Southeast Asia, helping you stay safe whilst exploring this remarkable part of the world.

Understanding Travel Vaccine Requirements

The Centers for Disease Control and Prevention (CDC) provides detailed guidance for travellers heading to Southeast Asia, recommending several vaccines based on your specific itinerary, duration of stay, and planned activities. Whilst some vaccines are recommended for all travellers, others depend on whether you'll be spending time in rural areas, your length of stay, and your planned activities.^[1][2]

It's important to note that New Zealand does not currently have vaccines available for chikungunya or dengue fever, despite these being significant health concerns in the region. However, other preventive measures and vaccines can substantially reduce your risk of illness whilst travelling.^[3][4]

Core Vaccines for All Southeast Asia Travellers

Hepatitis A

Hepatitis A is one of the most common vaccine-preventable diseases affecting travellers to Southeast Asia. This viral infection affects the liver and spreads through contaminated food and water, making it a significant risk even for short-term visitors staying in quality accommodation.^[1][2]

Mortality and Morbidity: Whilst most people recover from hepatitis A, it can cause severe illness requiring hospitalisation. The infection causes fatigue, fever, nausea, and jaundice (yellowing of the skin and eyes).^[5]

Vaccine Schedule and Protection:

·       First dose provides protection within 2 weeks^[6][7]

·       Second dose given 6-12 months later ensures long-term immunity^[5][6]

·       After completion of the two-dose series, protection lasts at least 17 years, possibly up to 30-40 years^[8][9]

·       A single dose provides protection for at least one year^[6]

Time to Effectiveness: Protection begins approximately 2-4 weeks after the first dose.^[2][6]

Available at 1 Health: We stock hepatitis A vaccine and can administer it on-site, ensuring you're protected well before your departure.

Typhoid Fever

Typhoid fever remains a significant health threat in Southeast Asia, with the region accounting for a substantial proportion of the global disease burden. This bacterial infection spreads through contaminated food and water and can cause severe illness.^[10][11]

Mortality and Morbidity: Typhoid fever causes approximately 216,500 deaths annually worldwide, with the majority occurring in Asia. The mortality rate varies by region, with case fatality rates in Asia averaging around 5.7%. Without treatment, complications can include intestinal perforation, which carries a mortality rate of approximately 15.6%. Children and young adults are particularly vulnerable, with the highest incidence rates occurring in these age groups.^{[12][11][13][10]}

Vaccine Options and Schedules:

Two vaccine types are available:

1.     Injectable vaccine (Typhim Vi):

Single dose administered at least 2 weeks before travel^[7][2]

Protection lasts approximately 2-3 years^[2]

Booster recommended every 2-3 years if ongoing risk

2.    Oral vaccine (Vivotif):

Four capsules taken over 7 days (one capsule every second day)^[2]

Complete course at least 10 days before departure^[2]

Protection lasts approximately 5 years

Booster recommended every 5 years if ongoing risk

Time to Effectiveness: Injectable vaccine provides protection 2 weeks after administration; oral vaccine requires completion of all four doses at least 10 days before travel.^[2]

Available at 1 Health: Both injectable and oral typhoid vaccines are available, and we can help you choose the most suitable option for your travel plans.

Japanese Encephalitis

Japanese encephalitis (JE) is a mosquito-borne viral infection and the most common vaccine-preventable cause of encephalitis in Asia. Whilst overall risk to short-term travellers is low, certain activities and travel patterns significantly increase exposure risk.^[14][1]

Mortality and Morbidity: JE is a serious disease with devastating consequences. The mortality rate ranges from 20-30% among those who develop symptoms. Of those who survive, 30-50% experience permanent neurological complications, including cognitive impairment, behavioural changes, and physical disabilities. Recent estimates suggest the case fatality rate has declined from approximately 26% in the 1960s-1970s to around 14% in recent years, though it remains a significant threat.^{[15][16][17][14]}

Who Needs This Vaccine:

·       Travellers spending more than one month in rural areas^[18][14]

·       Those visiting during transmission season (varies by country but generally associated with rainy seasons)

·       Travellers to endemic areas regardless of duration if engaging in high-risk activities (camping, cycling, outdoor activities)^[1][2]

·       Laboratory workers who might be exposed to the virus^[14]

Vaccine Schedule and Protection:

·       Two doses given on days 0 and 28^[2][14]

·       Accelerated schedule available: days 0 and 7 for last-minute travellers^[19]

·       Ideally complete the series at least 1 week before travel^[2]

·       Duration of protection: Current evidence suggests protection lasts at least 2-3 years after the primary series^[20][15]

·       Booster doses may be considered for those with ongoing exposure risk

Time to Effectiveness: Protection develops approximately 1 week after completing the vaccine series (approximately 7-10 days after the second dose).^[19][2]

Available at 1 Health: Japanese encephalitis vaccine is stocked on-site and can be administered according to your travel timeline.

Rabies

Rabies is one of the most feared travel-related diseases, and for good reason. Once symptoms appear, it is almost universally fatal.

Mortality and Morbidity: Rabies has the highest case fatality rate of any infectious disease, approaching 100%. Globally, rabies causes approximately 59,000 deaths annually, with 95% of cases occurring in Africa and Asia. Asia alone accounts for approximately 60% of global deaths. India has the highest burden, with an estimated 20,000 deaths per year, representing 35% of the global total. Children under 15 years account for 40% of all rabies deaths.^[21][22][23]

The majority of human rabies cases (99%) result from dog bites. Without post-exposure treatment, the probability of developing rabies following a bite from a rabid animal varies by location: head bites carry a 55% risk, upper extremity 22%, trunk 9%, and lower limb 12%.^[22][23][24]

Who Should Consider Pre-Exposure Vaccination:

·       Travellers spending extended periods in rural areas

·       Those likely to have contact with animals (veterinarians, wildlife researchers, adventure travellers)

·       Children (who are more likely to approach animals and may not report bites)

·       Travellers to areas where post-exposure treatment may be difficult to access

·       Cyclists, runners, and those engaging in outdoor activities where animal encounters are possible

Vaccine Schedule and Protection:

The Australasian College of Tropical Medicine recommends the following for most healthy travellers:

Pre-Exposure Prophylaxis (PrEP):

·       Two-dose schedule: Most cost-effective option for travellers

 Doses given on days 0 and 7

Requires booster before next trip to rabies-endemic areas

Not suitable for immunocompromised individuals or those over 50 years (who should receive 3-dose schedule)

·       Three-dose schedule: For extended stays or higher risk

Doses given on days 0, 7, and 21-28

Provides longer-lasting protection

Recommended for immunocompromised travellers

Duration of Protection:

·       Two-dose schedule: Effective protection for current trip; booster recommended before subsequent travel to endemic areas (recommended at least 12 months after first dose)

·       Three-dose schedule: Protection lasts at least 3 years; ongoing exposure may warrant periodic boosters^[19]

Time to Effectiveness: Protection develops approximately 7 days after completing the vaccine series.

Post-Exposure Requirements: If bitten or scratched by a potentially rabid animal:

·       Travellers who received pre-exposure vaccination require 2 additional doses on days 0 and 3

·       Travellers without pre-exposure vaccination require rabies immunoglobulin (RIG) plus 4-5 doses of vaccine

·       Important: RIG is not readily available in many parts of Southeast Asia. Pre-exposure vaccination eliminates the need for RIG, which can be extremely difficult to source overseas.

Available at 1 Health: Rabies vaccine is available, and we can discuss the most appropriate schedule based on your travel plans, activities, and medical history. For complete guidance, refer to the Australasian College of Tropical Medicine rabies guidelines.

Additional Recommended Vaccines

Hepatitis B

Hepatitis B is transmitted through contact with infected blood or body fluids, making it a concern for travellers who might require medical care, engage in certain activities, or have longer stays.

Mortality and Morbidity: Hepatitis B can cause both acute and chronic liver disease. Chronic infection can lead to cirrhosis and liver cancer. The global burden is significant, though many infections can be prevented through vaccination.^[25]

Vaccine Schedule and Protection:

·       Standard schedule: 3 doses at 0, 1, and 6 months^[26][25]

·       Accelerated schedule for last-minute travellers: 0, 7, and 21 days, plus a booster at 12 months^[19][26]

·       Duration of protection: After completing the primary course, protection is believed to last at least 20-30 years, possibly lifelong for most people^[26]

·       Booster doses are generally not required for immunocompetent individuals^[25][26]

Time to Effectiveness: Protection develops 1-2 months after completing the primary series. The accelerated schedule provides more rapid protection (65-98% protected within 1-5 weeks).^[26]

Available at 1 Health: Hepatitis B vaccine (Engerix-B) is stocked on-site, and we can provide both standard and accelerated schedules based on your departure date.

Cholera

Whilst cholera risk for typical tourists is low, certain travel patterns and humanitarian work increase exposure risk. Cholera is endemic in many parts of Southeast Asia.^[27][28][29]

Mortality and Morbidity: Cholera causes severe, watery diarrhoea that can lead to rapid dehydration and death if untreated. Without treatment, severe cholera can kill within hours. With prompt rehydration therapy, mortality drops to less than 1%.^[30]

Vaccine Schedule and Protection:

·       Dukoral® (available for travellers):

Two doses for adults (three doses for children 2-5 years)^[31][32]

Doses separated by 1-6 weeks^[32][31]

Must be given at least 1 week before travel^[31]

Duration of protection: 2 years in those 6 years and older; 6 months in children 2-5 years^[32]

Booster every 2 years if ongoing risk (every 6 months for young children)^[32]

·       Alternative vaccines (Shanchol™/Euvichol®):

Two doses separated by at least 2 weeks^[31]

 Duration of protection: 3 years^[31]

Single dose provides short-term protection^[31]

Time to Effectiveness: Protection begins approximately 1 week after completing the vaccine course.^[31]

Note: Cholera vaccine also provides short-term protection (approximately 3 months) against enterotoxigenic E. coli (ETEC), a common cause of travellers' diarrhoea.^[33][32]

Available at 1 Health: Oral cholera vaccine can be provided for high-risk travellers. We'll assess your specific itinerary to determine if this vaccine is recommended for you.

Routine Vaccines with Travel Considerations

COVID-19

COVID-19 vaccination remains important for international travellers, reducing the risk of severe illness and complications.

Vaccination Recommendations:

All international travellers should be up to date with COVID-19 vaccinations before travel^[19]

"Up to date" typically means completing a primary series plus recommended boosters

 Protection wanes over time, with effectiveness declining several months after vaccination^[34][35]

Available at 1 Health: COVID-19 vaccines are available for eligible individuals. We can advise on whether a booster is appropriate before your trip.

Influenza (Flu)

The flu circulates year-round in tropical regions like Southeast Asia, making vaccination important regardless of the time of year you travel.^[36]

Vaccine Schedule and Protection:

Single annual dose^[37][36]

Time to effectiveness: Takes up to 2 weeks to provide full protection, though some protection may develop within 4-6 days^[36]

Duration of protection: Effectiveness begins to wane approximately 41 days after vaccination, declining by approximately 9% every 28 days^[38][39]

Annual vaccination recommended due to both waning immunity and changes in circulating virus strains^[38]

Available at 1 Health: Annual influenza vaccine is available and strongly recommended for all travellers, regardless of destination.

Tetanus, Diphtheria, and Pertussis (Tdap)

Tetanus is a risk anywhere in the world through contaminated wounds. Ensuring you're up to date protects against this potentially fatal disease.

Vaccine Schedule and Protection:

Primary series: 3 doses in infancy plus boosters in childhood^[40]

Adult boosters recommended at ages 45 and 65 years in New Zealand^[40]

For travel: Booster recommended if more than 10 years since last dose^[40]

Duration of protection: After completing primary series and boosters, protection lasts at least 20-30 years in most adults^[40]

Booster every 10 years recommended for optimal protection, especially after tetanus-prone injuries^[40]

Time to Effectiveness: If previously vaccinated, protection develops rapidly (within days) after a booster dose due to immune memory.^[40]

Available at 1 Health: Tdap vaccine is available, and we can review your vaccination history to determine if a booster is needed before travel.

Measles, Mumps, and Rubella (MMR)

Measles outbreaks occur periodically in Southeast Asia, and the disease is highly contagious.

Mortality and Morbidity: Measles is far more serious than many people realise. Complications occur in approximately 10% of cases and include ear infections, pneumonia, and diarrhoea. Encephalitis (brain inflammation) occurs in 1 in 1,000 cases, with 15% of those affected dying and 25-35% suffering permanent neurological damage. The overall case fatality rate is 1-3 per 1,000 cases in developed countries but can be as high as 28% in areas with malnutrition and poor healthcare. Measles also suppresses the immune system for approximately 2 years after infection, increasing vulnerability to other diseases.^[41][42]

Vaccine Recommendations:

·       Two doses provide long-lasting (likely lifelong) protection^[42]

·       If born after 1969 and haven't received 2 doses, consider vaccination before travel^[2]

·       Particularly important for younger travellers and those who may not be fully vaccinated

Available at 1 Health: MMR vaccine is available for those requiring catch-up vaccination before travel.



Important Vaccines NOT Available in New Zealand

Dengue Fever

Unfortunately, New Zealand does not currently have a dengue vaccine available, despite dengue being a significant health threat in Southeast Asia. Dengue is transmitted by Aedes mosquitoes (which bite during the day) and can cause severe, sometimes fatal illness.

Prevention: Focus on mosquito bite avoidance:

·       Use insect repellent containing DEET, picaridin, or IR3535

·       Wear long-sleeved shirts and long trousers

·       Stay in air-conditioned or well-screened accommodation

·       Be especially vigilant during early morning and late afternoon when Aedes mosquitoes are most active

Chikungunya

Similarly, New Zealand does not stock chikungunya vaccine. This mosquito-borne viral disease causes fever and severe joint pain that can persist for months.

Prevention: Same mosquito avoidance strategies as for dengue.