Advice for health professionals

The Immunisation Handbook provides clinically relevant information about the polio immunisation schedule in New Zealand.

The Communicable Disease Control Manual describes the standard practice that public health services should follow in regard to the prevention and control of poliomyelitis in New Zealand.

Travel and blood clots

When you sit still for long periods of time – such as when you’re travelling – you increase your risk of blood clots. This is because sitting still slows the blood flow from your legs back to your heart.


  • Restricted leg room can slow the flow of blood even more, particularly when the back of the seat in front is pressing on your shins.
  • When blood forms clots in the deep veins of the legs, usually the calves, it’s called deep vein thrombosis.
  • If that clot passes up the veins and to the heart it can become stuck in one the blood vessels supplying the lungs. This can cut off the oxygen supply to the body. This is known as a pulmonary embolism. It can be fatal.

People at risk

Some people have a higher risk of deep vein thrombosis, including:

  • pregnant women
  • women taking the pill
  • people who have had a recent operation
  • those over 40
  • smokers
  • people with cardiovascular disease
  • people with a family history of blood-clotting disorders.

If you fit into any of these categories, you should be extra careful to prevent deep vein thrombosis when you are travelling.

Other things you should know

  • Passengers flying in first class or business class can also get blood clots in their legs, even though there is more leg room.
  • Blood clots can form on journeys as short as 3 hours.
  • Deep vein thrombosis can happen on long bus or train journeys as well as on planes.


If you think you might have a deep vein thrombosis, see your doctor. The symptoms are usually:

  • swelling on one lower leg
  • tenderness deep in your calf
  • the veins under the skin of your lower leg becoming more prominent (darker and raised) and sometimes the skin being dusky compared to the other leg.

Sometimes deep vein thrombosis can affect both legs, and can spread above your knee.

Call Healthline 0800 611 116 if you are unsure what you should do.


You can reduce your chance of deep vein thrombosis by following these tips, especially if you’re in a high risk group.

  • Try to get a seat with extra leg room, such as one next to an emergency exit.
  • Drink plenty of water in order to reduce dehydration (which increases the risk of blood clots), especially if you’re drinking alcohol or drinks containing caffeine.
  • Don't stay in your seat throughout the flight – walk around the plane often. An aisle seat makes this much easier.
  • While seated, exercise your calf muscles every half-hour by flexing and rotating your ankles for a few minutes.
  • Sleep only for short periods and don’t take sleeping pills that could keep you motionless in your seat for hours.
  • Consider wearing support stockings during the flight to reduce the risk of clots.
  • Avoid wearing tight clothing around your waist.

If you think you have an increased risk of thrombosis and are worried about it, contact your doctor.

Measles outbreaks

Measles is a highly contagious disease that can be life threatening. Right now, there are measles outbreaks happening across the globe. People travelling overseas should make sure they are fully immunised against measles before they go. 

Current outbreaks

There are currently measles outbreaks in: 

  • India 
  • Yemen 
  • Somalia 
  • Zimbabwe 
  • Pakistan 
  • Ethiopia 
  • Liberia 
  • Indonesia 
  • Nigeria 
  • Angola 

Measles may also be present in other countries as outbreaks continue to affect many different parts of the world. Check the latest travel information and advice for your destination: 

Things you should know about the vaccine

  • 2 doses of the MMR vaccine gives long-lasting protection against measles to at least 98% of people.  

  • MMR vaccination is free for all eligible New Zealand residents

  • Ask your doctor, parent, or caregiver if you had your 2 measles vaccinations as a child, or check your Well Child Tamariki Ora or Plunket book. If you're still not sure, play it safe and get an MMR vaccine. There are no safety concerns with having an extra dose, even if there is a chance you’ve already had two doses of the vaccine. When you receive a dose, it will be recorded against your health record. 

  • If there is not enough time before you travel to complete the recommended 2 doses, having even one MMR vaccination before you leave New Zealand will substantially reduce your (or your child’s) risk of getting infected. 

  • You can get your measles vaccination at your doctor, nurse, healthcare provider, or some local pharmacies. 

Other illnesses to avoid

Japanese encephalitis

There is an outbreak of Japanese encephalitis (JE) in Australia. Information about the outbreak is available on the Australian Government Department of Health website.

Japanese encephalitis is a disease transmitted to humans by mosquitoes infected with the Japanese encephalitis virus. Most infections are asymptomatic or with mild symptoms, but occasionally (less than one percent of cases) it can result in severe disease and/or death. Initial symptoms are usually a sudden onset of fever, headache and vomiting and present about 5 to 15 days after infection. If you develop symptoms, have been in an affected region in Australia and think that you may have been infected with Japanese encephalitis virus, seek urgent medical assistance

Japanese encephalitis virus is not present in New Zealand.

If you are planning to travel to Australia or to another country with diseases transmitted by mosquitoes, the best protection is to avoid mosquito bites. 

A vaccine against Japanese encephalitis is available in NZ. However, vaccination needs to be planned in well in advance of the travel with travel health clinics.


Here are polio outbreaks in a number of countries overseas. The current list of polio-infected countries is available on the Global Polio Eradication Initiative website.

The World Health Organization (WHO) recommends that all travellers to polio-affected areas be fully vaccinated against polio. Residents (and visitors for more than 4 weeks) from infected areas should receive an additional dose of OPV or inactivated polio vaccine (IPV) within 4 weeks to 12 months of travel.

The 3 October 2019 statement of the 22nd IHR Emergency Committee Regarding the International Spread of Poliovirus is available on the WHO website.

More information about the situation in infected regions can be found on the WHO website and the Global Polio Eradication Initiative website.

Avoiding bug bites while travelling

Bugs like mosquitoes, ticks and tsetse flies can give you diseases when they bite you. While mosquitoes in New Zealand don’t carry diseases, in other countries they can be dangerous.

Cover up

Wear long, loose fitting, light coloured clothing - ticks and other critters are more easily detected on a light background and tsetse flies are attracted to dark, contrasting colours.


  • Use a repellent, preferably containing less than 35 percent diethyltoluamide (DEET). Always read the instructions
  • Apply repellent after sunscreen.

Important repellent information

Use insect repellent, preferably containing diethyltoluamide (DEET). High concentrations of DEET protect better, but concentrations over 35% (about 350 g/L) are not recommended if there is a choice of products available. This is because in rare cases they can cause poisoning. Other products containing 20–25% picaridin (about 200–250 g/L) and those containing about 30% oil of lemon eucalyptus (equating to about 20% para-methane-diol (PMD)) can also be used. Repellents should not be applied to wounds, irritated skin, eyes or mouth.

Note that vitamin B doesn’t prevent mosquito bites.


  • Stay in places with screens on windows and doors or sleep under mosquito nets.
  • Use air conditioning or fans if available.
  • Use insect sprays indoors when mosquitoes are around.
  • Use mosquito coils.
  • Stay away from places where mosquitoes are most active or breeding such as stagnant water.
  • Use zip-up screens on tents.

The Safe Travel website has more detailed information about health risks overseas, including diseases like dengue or malaria that are carried by insects. Check their site for current health alerts.

Bugs to be aware of

  • Mosquitoes that carry malaria or Japanese encephalitis are more active in the evening and at night. If you’re travelling in an area that has these diseases, be especially vigilant at those times.  
  • Mosquitoes that carry dengue, yellow fever or Zika are more active in the daytime.
  • Tsetse flies are large flies found in mid-continental Africa, particularly in vegetated areas. Their bite can cause sleeping sickness.
  • Ticks flourish in warm, humid climates such as the Australian bush. They can carry many diseases.