Your grandchildren may not need to take anti-malaria medication. It depends where they are visiting in Sri Lanka.

Dr Ron Behrens, a travel medicine expert at the London School of Hygiene and Tropical Medicine, advises that if your family are visiting the main tourist areas of Colombo and Gall, they should be fine. If they are planning to travel outside these areas, medication is advised as the risk of infection with malaria varies in different parts of the country.

It’s important for your grandchildren to take medication if it is needed, as malaria is potentially fatal. It is transmitted through a species of mosquito that bites only between dusk and dawn, so avoiding bites during this period is important. The malignant form of malaria is uncommon and usually develops within weeks of return from travelling. The benign, or relapsing, form can occur up to a year after return. Unfortunately, the symptoms — fever, headaches, shivering, joint pains and diarrhoea — can mimic many illnesses, including flu, but malaria can be cured completely if treatment is given early.

If medication is needed, there are several options. Mefloquine (known as Larium) is the simplest regimen. It needs to be taken only once a week and the small tablet can be divided into appropriate portions for children.

Although many travellers are concerned about the side-effects of Lariam, a component of this medication, there is little evidence that children encounter problems when using mefloquine.

Cholorquine, another medication, comes in syrup form and needs to be combined with proguanil, which comes as a pill and has to be taken daily. A pharmacist will calculate the size of the dose required. Malarone is available in paediatric-sized tablets but is taken daily and is more expensive. The side-effects of this medication are usually nausea or indigestion. It is important to take it with food.

The deep-impregnated wrist and leg bands you mention are a good idea, too. They contain Deet, a mosquito repellent, and can help to prevent insect bites. However, they should not be considered as a substitute for anti-malaria medication.

Other frequent health problems encountered in this region include diarrhoea, heat problems, eye and ear infections, and for young children the risk of rabies needs to be considered.

Your grandchildren should always wear something on their feet to avoid picking up parasites. Some jabs may be necessary, too, including hepatitis A and typhoid. More details and information about the London School of Hygiene and Tropical Medicine’s travel clinic are available at www.thehtd.org.

Cyclical vomiting

My 12-year-old daughter suffers from cyclical vomiting every three to six weeks. It starts with pains in her tummy, followed by shaking, then vomiting, which happens up to five nights at a time. She is not gaining weight quickly and has had to have five teeth removed as they had rotted. We have tried a dairy-free diet, with no fizzy drinks and monitoring her sugar intake. Her doctor says that she will grow out of it. Is there anything we can do? Sara Ponsford, by email

It sounds as though your daughter is suffering from cyclical vomiting syndrome, a well recognised condition, which can be very frustrating for those who have it. It often follows a pattern in the way you describe. Stretches of being well are followed by a build-up period which leads to intense nausea and vomiting, often at night, for several nights. Vomiting brings acid into the mouth, which can cause teeth enamel to wear out, as your daughter has experienced.

Her doctor is right to say that she will probably grow out of it. Adults can have cyclical vomiting syndrome, but it is more often seen in children. Identifying a cause can be difficult, but I would expect your daughter to have had a range of investigations to exclude underlying problems such as middle ear, kidney and metabolic problems that could be linked to her condition. Investigations might include a middle-ear test and examination of her balance, a series of blood tests, a barium test to check the structure of her gut and an abdominal ultrasound.

If no specific cause can be found, medication can help to relieve the symptoms. A new generation of medication is proving quite effective, although there is as yet no cure for the condition. Contact the Cyclical Vomiting Syndrome Association (www.cvsa.org.uk) for further information.

Jane Collins is the chief executive and honorary consultant paediatrician at Great Ormond Street Hospital

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