5. The Control Strategy: The solution: safe, cheap, repeated treatment with deworming drugs. Then and Now – What simplified the strategy ?
Three significant changes meant that it was possible to greatly simplify therecommended control strategy for worms. 1. Drug costs
The price of the drugs to control schistosomiasis and STH plummeted. § Two to three years ago albendazole2 cost about $0.20/tablet, it is now less than
§ Before the patent was lifted for praziquantel, a tablet cost about $3. It now less
Prior to this drop in price, each person was screened for infection and then treatedaccordingly. Now it is possible to mass treat, in fact, individual diagnosis is now 4-10times more expensive than the treatment itself. Cost per child: Using the school system for delivery, the cost of treating a child is typically less than 0.50 US$ per year where both schistosomiasis and the common intestinal worms are present. Where only the latter exist, the cost is less than 0.25 US$per child per year. This price covers the cost of the drugs, their delivery, the equipment, health education materials, training for implementing personnel and 2. Goal of the programme: Reduce Intensity
Twenty years ago, the goal of any worm control strategy concentrated on reducingthe number of people who were infected. The prevalence. However, unlesssanitation is improved, people are constantly re-infected - the prevalence often doesnot show a dramatic drop. The estimated percentage of people infected with wormsin Africa for example, has not decreased despite control efforts in the 1980s.
The approach is now radically different. Instead of reducing the number of people with worms, reducing the numberof wormsin each person (the number of people with high worm loads) is recognized as vitally more important for that person's health. This approach implicitly recognizes that re-infection will occur until effective clean water and sanitation facilities are installed. While these are hugely important, they take time.
Regular treatment keeps the number of worms in a person low. This means that theinfection is never allowed to develop into critically debilitating disease.
2 The recommended drugs for treating soil transmitted helminths are Albendazole, Mebendazole, or Levamisol or Pyrantel. 3 Prevention and Control of Schistosomiasis and Soil-Transmitted Helminthiasis: Report of a Joint WHO Expert Committee, WHO, Geneva, 2002; Helminth control in school-age children: A guide for managers of control programmes, WHO, Geneva, 2002
The claim that therapy is irrelevant because children become re-infected collapses in
the face of the remarkable improvement in health achieved after treatment. 3. Piggy-backing for the long run
Previous programmes were often set up vertically and invariably funded by externaldonors. When funding was withdrawn, the programmes very often collapsed.
The recommendation now is to do the opposite: deworming can and should be piggy-backed onto existing networks. This slashes the cost of delivery and makes theprogramme intrinsically more stable and therefore long-lasting.
• Use the school systemThe school system offers one of the most efficient channels to reach school agechildren in addition to having other clear advantages:
• Teachers, with minimal training, can organise deworming days and safely
• Even where school enrolment rates are low, schools can be used to reach non-
• Healthier children increases attendance, reduces class repetition and boosts
educational attainment. Those who gain the most are the least advantaged: girlsand the extremely poor.
• Using schools to deliver deworming drugs is the most cost effective way to
regularly reach the priority high risk group. Involving non-medical people
Deworming requires no specialized training, no injections, no complicated drug
regimens. The drugs are safe and easy to administer.
This means non-medical people like school teachers, can be given a basic training
which allows them to distribute the drugs.
There are 3 immediate advantages to such an approach.
§ It takes some of the pressure off already overloaded district health staff. § Teachers are often respected and trusted members in a community making them
extremely well-placed to carry out such activities.
§ The coverage of a programme can be dramatically improved by using the school
• Use special health campaignsMass health campaigns offer a unique opportunity to reach thousands of people veryeffectively. For example national immunization days, vitamin A supplementationprogrammes, feeding programmes, and water and sanitation initiatives. Stock local health posts and pharmacies
In addition to the regular deworming of the school population, treatment should beeasily available at the most peripheral health posts. Global Commitment and the Global Target:
In 2001 at WHO's World Health Assembly, a Resolution was put forward urgingall endemic countries to seriously start tackling worms.
Resolution 54.19 was endorsed by every single Member State which triggered twoimportant spin-offs. First a measurable global goal was set and second the Partnersfor Parasite Control (PPC) was established. For more information see the link on thissite to the PPC at: http://www.who.int/wormcontrol/about_us/background/en/
Two important meetings have been recently organized by WHO to guiderecommendations and produce updated guidelines for control. 1. WHO Expert Committee Meeting: The first was in October 2001 when the WHO Expert Committee working on parasite control completed its examination of the technical aspects of the proposed treatment.
The report is posted on this site under 'Documents and Publications à WHODocuments à EC (December 2001)
2. Informal Consultation: The use of anti-helminthic drugs in children less than 24 months old and the use of Praziquantel during pregnancy In April 2002, the use of anti-helminthic drugs in children less than 24 months old and the use of Praziquantel during pregnancy was assessed by a WHO informal expert Committee.
The consultation concluded that it is both safe and recommendable to de-worm
children over 1 year of age4 for STH in endemic countries and to include women inpraziquantel distribution campaigns and whenever they come in contact with healthservices.
The report is posted on this site under 'Documents and Publications à WHODocuments à WHO Report of the Informal Consultation on the Use of Praziquantelduring Pregnancy/Lactation and Albendazole/Mebendazole in Children under 24Months. WHO Geneva (Document WHO/CPE/PVC 2002/4).
4 WHO Report of the Informal Consultation on the Use of Praziquantel during Pregnancy/Lactationand Albendazole/Mebendazole in Children under 24 Months and albendazole/mebendazole in childrenunder 24 month. WHO Geneva (Document WHO/CPE/PVC 2002/4)
Dechra Veterinary Products Limited (A business unit of Dechra Pharmaceuticals PLC) Sansaw Business Park Hadnall, Shrewsbury Shropshire SY4 4AS Tel: 01939 211200 CARDISURE ® FLAVOURED 1.25 MG, 2.5 MG, 5 glucose levels should be carefully monitored. As MG AND 10 MG TABLETS FOR DOGS pimobendan is metabolised in the liver, particularcare should be taken when administering the product Quali