Elderly tourists are up to 10 times more likely to die of malaria than younger travellers, a new study has revealed.

Researchers from the London School of Hygiene and Tropical Medicine and the University of Oxford found that the risk of dying from the disease for tourists who have visited a malaria-infected country increases steadily with age.

Holiday makers over the age of 65 are almost 10 times more likely to die from the disease than those who are aged 18-35, they revealed in a study published online by the British Medical Journal (bmj.com).

After analysing 20 years of UK data involving over 25,000 patients, the research team agreed that people of African heritage travelling to visit friends and family are far more likely to get malaria, as many do not take anti-malaria drugs.

However, tourists travelling from Europe, especially on winter sun holidays in Africa are far more likely to die from the disease once acquired.

Their findings have prompted a call to doctors advising them to give pre-travel advice, including the importance of taking anti-malaria drugs, and encourage returning travellers who develop a fever or other flu-like symptoms, to see their GP.

The medical profession should also be targeting travellers of African heritage, the researchers say.

"Increasing age was strongly and independently associated with an increasing risk of death from malaria," the researchers stated.

They found that 4.6% of cases were fatal in people aged over 65 (25 deaths in 548 cases), compared to an overall case fatality of 3% (81/2740) in tourists, and 0.32% (26/8077) in travellers visiting friends and relatives.

There were no deaths in children under five years.

The UK study also showed that case fatality was particularly high in people visiting the Gambia (3.9%) compared with any other West African country (0.4%).

Ireland has the third highest rate of imported malaria in the EU, third only to France and the United Kingdom.

The number of cases in Ireland has increased steadily in recent years, from about 20 cases in 2001 to more than 80 cases in 2010.

Three quarters of people with malaria were hospitalised and three deaths were recorded between 2005 and 2010.

For tourists, low drug prevention rates and low awareness of the dangers of malaria may well be factors for death from malaria.

The UK study showed that death rates increase in December with over a quarter of deaths occurring then, which may be due to travellers mistaking symptoms for common winter viruses, or getting less rapid diagnosis over the holiday period.

Malaria is caused by a parasite called Plasmodium, which is transmitted by the bites of infected mosquitoes.

Symptoms of malaria include fever and flu-like illness, including shaking chills, headache, muscle aches, and tiredness. Nausea, vomiting, and diarrhoea may also occur.

Symptoms usually appear between 10 and 15 days after the mosquito bite. If not treated, malaria can quickly become life threatening.

Read more on travel health here