Relative risks: the homecoming myths

By Dr Eddy Bajrovic*

Thousands of Australian citizens and residents of Asian heritage will journey ‘home’ to their country of origin in coming weeks to celebrate the Lunar New Year.
In China, Lunar or Chinese New Year is a major holiday and its many regional neighbours – especially those with significant Chinese populations – celebrate the event on or around the same date as China. This year – the year of the monkey – it falls on February 8.
But, this annual cultural and religious event isn’t so much a single night filled with fireworks and fun as a festival extending over several weeks to herald the northern hemisphere spring.
The homecoming provides an opportunity to reunite with far-flung family and friends. During their stay the visitors from ‘Down Under’ often live in family homes in metro and rural areas.
But, the Lunar New Year celebrations can have serious health implications for both travellers and the wider Australian community.
Studies have shown that people travelling to visit friends and relatives (collectively referred to as ‘VFRs’ by travel medicine experts) are at much higher risk of illness than any other category of traveller, particularly if they visit a developing country.

Higher rates of serious travel diseases

In Australia health statistics, VFRs are heavily over-represented in cases of serious infectious diseases like measles, hepatitis A, and typhoid fever, as well as malaria infections requiring hospital treatment.
That’s because they:
- Often stay longer than the average visitor.
- Live more like locals than tourists, staying in local homes, eating home-cooked meals and drinking the local water.
- Frequently spend time in rural areas where sanitation is typically poor and they are more likely to encounter a number of common infectious diseases.
- Are more likely to stay in malaria-infected areas, and have greater exposure to other mosquito-borne diseases, such as the increasingly common urban viruses, dengue, chikungunya and Zika.
Yet, research has shown many VFRs don’t appreciate the potential health risks associated with travel to developing regions. Not only are they less aware, but they are less likely to seek pre-travel health advice, and more likely not to have the vaccines usually recommended.
As a result, not only is their health at risk, but so too is that of vulnerable fellow passengers on flights and the people in their community back home. And, with every new case of highly infectious measles, authorities spend tens of thousands of dollars trying to track and notify those in contact with the infected person. 

The ‘I-was-born-here-I-must-be-immune’ myth

It seems reasonable to think that if you (or your parents before you) have survived the more common diseases present in your country of origin it must be safe to return there without taking any precautions. Surely you must have some innate immunity, right?
It’s a common perception among VFR travellers. Unfortunately, it’s a myth.
The reality is:
- Any immunity to malaria or typhoid gained from being infected while growing up in the country of origin is quickly lost after leaving – usually within 6 months.
- Hepatitis A, a significant risk in most developing countries, is one disease where past infection provides life-long immunity. But, a parent’s immunity is not shared by their kids: they are vulnerable unless they are vaccinated. In a study of more than 600 cases of travel-related hepatitis A over an 8-year period, the vast majority of patients (70-91%) were VFR travellers and their children. 
- People born overseas are less likely to have received the routine vaccinations that children born here receive, including measles, mumps and whooping cough. So, they are vulnerable when they travel to developing countries, which typically have higher rates of these diseases.
Indeed, diseases, such as tuberculosishepatitis Bcholera, and various sexually transmitted infections are actually more common among returned VFR travellers than among other types of travellers. 

Steps to help ensure a health holiday

A few simple measures can help ensure a healthy homecoming. During your stay…
Reduce your exposure to germs: Make it a habit to wash your hands often – especially after using the toilet and before eating.
Avoid insect exposure: In Asia, mosquitoes spread malariadenguechikungunyaZika virus, and Japanese encephalitis, among other diseases. If you are staying in a family home without door or window screens or air-conditioning, take along a permethrin-treated bed net to sleep under, and take other measures to avoid insect bites during the day and at night.
Choose safe food and water guidelines: Consuming contaminated food or water can cause illnesses such as hepatitis Atyphoid fever, and travellers’ diarrhoea. Food cooked to high temperatures is usually the safest option, but be wary of meals involving raw seafood, locally made dairy products, and leafy salads.
Be aware of bird flu: Outbreaks of H5N6 and H7N9 avian influenza (‘bird flu’) strains continue across Asia. Most human cases followed contact with live or dead poultry, or birds. While bird flu can be deadly, it’s generally a low risk for travellers. Picking up a seasonal flu virus is much more likely.
Don’t pat or feed animals: Rabies is a deadly, vaccine-preventable disease. It’s present in many countries, but the highest incidence is in Asia – including major cities, such as Beijing and Ho Chi Minh City. Travellers should be aware of how to avoid rabies and what steps to take if bitten by a dog or other animal.
Choose safe transportation: Motor vehicle crashes are the leading cause of death of otherwise healthy travellers overseas.

Get some healthy travel advice – soon

If you are heading to Asia for Lunar New Year celebrations, act soon. Call Travelvax on 1300 360 164 this week and get no-obligation, country-specific advice over the phone.
You can also make an appointment to speak with a team of travel medicine professionals.
We’ll also advise you to:
- Take out appropriate travel health and medical evacuation insurance. (Medicare will not pay your medical or hospital bills overseas).
- Pack a first-aid kit suitable for your destination, length of your stay and, if it’s to be shared, the number of people travelling.
Illness after travel is not uncommon. See a doctor as soon as possible – especially if you developed a fever – and remember to mention your homecoming holiday.

* Dr Bajrovic is the Medical Director of Travelvax Australia.