However, most cases are easy to treat, explains Tina Green
Threadworm is most common among children under the age of 10 and surveys have highlighted that up to 30 per cent of pre-school children can be affected. Infection rates start to rise in October and tend to reach a peak in midwinter.
Anyone can get threadworms - they are not a sign of poor hygiene, and family pets are not responsible for harbouring or transmitting them.
What are threadworms?
Threadworms (Enterobius vermicularis) or 'pinworms' look like wriggling pieces of white cotton thread, about 2-13mm in length. They live in the rectum and are generally harmless, although there can be some rare complications. They are especially common in younger children but can spread to all the family.
The threadworm life cycle
Once eggs are swallowed, larvae hatch in the small intestine. Adult worms reside in the colon, living for about six weeks. A female threadworm can lay up to 16,000 eggs during her short life. Adult females move to the opening of the anus and deposit eggs just outside, usually at night-time.
This causes irritation and itching around the anal area. If the child scratches, eggs collect on the fingers and under the nails. Infection can spread to clothing, towels and bedding, then infect other family members.
How do threadworms spread?
Eggs stuck under the nails or on the fingers are transferred between children in schools and nurseries or to the family at home. They easily get transferred to the mouth and some may be swallowed. The sharing of bath towels is another way in which they can spread. They can survive for up to two weeks on clothing, bedding, in carpets and within household dust. The habit of thumb sucking and sucking other fingers is strongly associated with the prevalence of threadworms.
Threadworm symptoms
The main symptom is itching around the anal area, which occurs particularly at night. The child may also develop a sore bottom. Sleep may be disturbed and some children also start bed-wetting. However, nine out of ten threadworm sufferers do not show any symptoms.
Threadworm treatment
Effective threadworm treatments are available from the pharmacist without a prescription. The two most frequently recommended treatments are piperazine and mebendazole.
To help prevent infection and reinfection, the whole family should be treated at the same time and should follow the simple hygiene measures listed below.
Preventing infection
To prevent infection or re-infection, some simple hygiene measures should be taken. To prevent re-infection, these measures should be followed for six weeks (the life span of the adult worms) to help break the infection cycle.
Every child and adult in the house should:
* Wash hands and scrub under the nails, after using the toilet or changing nappies, and before eating or preparing food
* Wear pyjamas or pants at night and change them daily
* Wear clean underwear every day
* Have a bath or shower and wash around the anal area every morning
* Keep nails short and clean.
Every child and adult in the house should not:
* Share towels
* Eat food in the bedroom.
Bedrooms should be vacuumed daily and sheets changed frequently.
When to see the doctor
For most cases of threadworms the pharmacist will be able to recommend the most suitable remedy. However, there are some situations when it is advisable to consult a doctor.
The following children and adults should see a GP before beginning treatment for threadworms:
* Pregnant or breastfeeding women, or women who are trying to become pregnant
* Anyone with a history of epilepsy, intestinal blockage, liver disease, decreased kidney function or neurological disease
* If re-infection keeps occurring
* If any other parasitical infection is present, such as roundworm.
Children under the age of two should not be given mebendazole, but the pharmacist will be able to advise about this. Further information
* Threadworm Action Month is currently running. Badges are available saying 'Ask me about Fred' and carrying the cartoon picture of Fred the friendly worm. 'I know about Fred' wrist bands are available to give to everyone asking advice. Information leaflets, posters and checklists are also available. For more details, visit: www.fredworm.co.uk