Setting up community-directed treatment with ivermectin (CDTI): how it works and who does what
Selecting and training volunteers
The process begins when a health worker visits the chief of an affected community. Together they arrange a meeting with the entire community. At the meeting, the concept of community-directed treatment with ivermectin is explained.
The community then meets and decides if they want to adopt the strategy. If they decide they do want to go ahead, they decide when it is convenient for them to distribute ivermectin, and how and where treatment would take place. Communities also decide who among them they want to put forward for training as community-directed distributors or CDDs, and how to remunerate the CDDs within their cultural context.
The community informs the health worker of a preferred date for training the new CDDs. Training is carried out by the health workers, who usually train people from several different communities at the same time. The health workers are themselves trained at special training workshops run by the ministry of health, non-governmental development organizations (NGDOs).
CDDs are trained to:
- conduct a census
- use measuring sticks to estimate how many ivermectin tablets to give
- detect and treat minor side effects
- refer cases of severe adverse events to the nearest health facility
- fill in household treatment forms
- keep records
- report about the treatment campaign.
CDDs also learn about the criteria for exclusion to ivermectin treatment, and about the storage and management of the ivermectin tablets.
When the instruction is complete, the newly trained CDDs conduct a census of their community. They record the results in a notebook or in a printed community register, which is usually kept in the home of the community chief or with the CDD. The results tell the CDD how many ivermectin tablets are needed.
Collecting and distributing treatment
The entire community decides on the dates of the ivermectin distribution. The CDDs then collect the ivermectin tablets from the nearest health post on a date previously agreed with the health workers. The delivery of ivermectin from the country’s port of entry to the health post is arranged by the Onchocerciasis Task Force, which is made up of the national or local government and the NGDOs working in the country.
The CDDs begin distributing the tablets on the dates agreed by the community. Virtually all eligible people in the community are treated. The CDDs monitor any adverse reactions and treat cases of minor reactions where possible. They refer any difficult or severe cases to the nearest health facility. The CDDs then complete the treatment record forms and return a copy of these forms to the health post from where they collected the ivermectin. Health workers monitor the treatment records during visits to the communities.
Repeating treatment each year
A single dose of ivermectin has to be taken once a year for 16–18 years to break transmission of the parasite that causes onchocerciasis. This is because the drug only kills the larval forms of the parasite (microfilariae) and not the adult worms, which can live for around 14 years in the human producing more microfilariae each day. It is only when the adult worm dies naturally that a person is free of infection. However, as the microfilariae are responsible for most of the symptoms, a single dose of ivermectin is enough to relieve the intense itching and to halt progressions towards blindness and severe skin rashes caused by the disease.
To carry out their duties effectively, the CDDs are re-trained every year or every two years.