«A guide for programme managers WHO Library Cataloguing-in-Publication Data Trachoma control : a guide for programme managers. Published jointly by ...»
A guide for programme
WHO Library Cataloguing-in-Publication Data
Trachoma control : a guide for programme managers.
Published jointly by the World Health Organization, the London School of
Hygiene & Tropical Medicine, and the International Trachoma Initiative.
Includes 30 slides on the assessment of trachoma and a CD-ROM which contains
electronic versions of forms, an antibiotic requirement estimator, a template budget
and a generic evaluation manual.
1. Trachoma - prevention and control. 2. Trachoma - drug therapy. 3. National health programs - organization and administration. 4. Program evaluation. 5.
Guidelines. I. Solomon, Anthony W. II. World Health Organization. III. London School of Hygiene and Tropical Medicine. IV. International Trachoma Initiative.
ISBN 92 4 154690 5 (NLM classification: WW 215) © World Health Organization 2006 All rights reserved. Publications of the World Health Organization can be obtained from WHO Press, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 3264; fax: +41 22 791 4857; email: firstname.lastname@example.org). Requests for permission to reproduce or translate WHO publications – whether for sale or for noncommercial distribution –
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Printed in Switzerland Contents Preface
2.1 How to grade trachoma
2.2 How to train people to grade trachoma
2.3 How to validate trachoma grading
2.4 How to determine the burden of disease
3.1 How to provide surgical services for trichiasis (‘S’)
3.2 How to give antibiotics (‘A’)
3.3 How to promote facial cleanliness (‘F’) (and trachoma control in general)
3.4 How to improve water and sanitation (‘E’)
4.1 How to gain support for the programme
4.2 How to analyse the available data
4.3 How to calculate your ultimate intervention goals
4.4 How to plan the programme
4.5 How to prepare a budget
4.6 How to finance the programme
4.7 How to set priorities for intervention
5 Monitoring and evaluation
5.1 What are monitoring and evaluation?
5.2 How to monitor the programme
Preface Trachoma is an infectious eye disease that causes blindness; it is prevalent in many poor rural communities. The World Health Organization has set the year 2020 as the target for global elimination of trachoma as a public health problem.
To reach this target, the SAFE strategy (Surgery for trichiasis, Antibiotics to treat Chlamydia trachomatis infection, and Facial cleanliness and Environmental improvement to reduce transmission of C. trachomatis from one person to another) is recommended for districts and communities with endemic disease.
This guide has been written for managers of national and district trachoma control programmes. It sets out, step-by-step, what is needed to assess the magnitude and extent of the trachoma problem in the area and how to plan, implement, monitor and evaluate a programme to control, and ultimately eliminate, trachoma.
Throughout this guide, the term ‘community’ is used to refer to the minimum number of persons for whom mass trachoma control is to be implemented (for example, a defined group of households, one village or a group of neighbouring villages). The term ‘district’ is defined as the usual administrative unit for health care management, and the term ‘region’ is used to indicate the administrative unit one level higher than the district. These definitions and definitions of other terms used are found in the glossary.
Templates for a number of forms recommended for use in a programme can be found in the annex. To allow adaptation of the forms for use in a specific programme, electronic versions are available on the CD-ROM that accompanies this guide. The CD-ROM also contains an antibiotic requirement estimator (section 3.2.4), a template budget (section 4.5) and a generic evaluation manual (section 5.3).
We hope you find these materials useful.
1. Background Trachoma is a major cause of blindness. It affects very poor people living in rural areas, where access to water and sanitation is limited. It is caused by a bacterium called Chlamydia trachomatis, which is passed from the eyes of one person to those of another by flies, fingers or shared cloths or towels. Repeated infection with these bacteria over many years produces scarring of the inner part of the upper eyelid, which turns the lashes inwards so that they scratch the eyeball. Eyelid scarring also causes poor tear secretion and drying of the eye. These conditions increase the risk of corneal ulceration and scarring.
Scarring of the cornea impairs vision.
C. trachomatis infections of the eye are commonest in young children. They are associated with a group of clinical signs known as ‘active trachoma’. The condition in which the eyelashes are turned inwards is called ‘trichiasis’. A person’s risk of trichiasis probably increases in relation to the total number, duration and intensity of C. trachomatis infections during his or her lifetime. As a result, trichiasis tends to occur more commonly in women, because they tend to spend more time than men do with children, who are most frequently infected. It also becomes more and more common with increasing age. Implementation of trachoma control activities is prioritized in communities where the prevalence of active trachoma in children aged 1–9 years is 10% or higher or where the prevalence of trichiasis in people aged 15 years and over is 1% or higher.
Places in which trachoma is known to be endemic are shown in Figure 1.
Within many of these areas, however, the distribution of trachoma is focal, affecting certain communities, and within these communities only some households. In some areas, trachoma is a problem in nearly all rural communities.
Blindness due to trachoma is irreversible once it has occurred, but it can be prevented. The SAFE strategy (Surgery for trichiasis, Antibiotics to treat C.
trachomatis infection, and Facial cleanliness and Environmental improvement to reduce transmission of C. trachomatis from one person to another) is recommended for the control of trachoma. With the SAFE strategy, the World Health Organization (WHO) and its partners are targeting the Global Elimination of Trachoma as a cause of blindness by the year 2020 (GET2020). GET2020 is one element of a broader strategy known as ‘VISION 2020: The Right to Sight’, which has as its goal the elimination of all avoidable blindness by the same year.
Figure 1. Global distribution of trachoma.
Administrative areas in which trachoma is known to be a public health problem are shaded dark grey. Areas in which trachoma is believed to be a problem, but for which no data are available, are shaded light grey.
People are examined for clinical signs of trachoma for one of two reasons:
(1) to determine whether they have trichiasis and therefore require surgery; or (2) to measure the prevalence of clinical signs of trachoma.
The latter allows determination of whether trachoma is a public health problem, assists in selection of locations in which interventions are a priority and provides baseline or follow-up data for monitoring and evaluation of the control programme.
In this section, we explain how examinations and assessments are carried out.
Even if you do not examine people for trachoma yourself, it is important to understand how it should be done and what your examiners are looking for.
Pictures of a normal conjunctiva and the signs of the WHO simplified grading scheme are shown on the enclosed trachoma grading card; if you are unfamiliar with these signs, it is recommended that you examine the card as you read.
2.1 How to grade trachoma 2.1.1 Know the appearance of the normal eye In a normal eye, none of the eyelashes touches the eyeball. The cornea is smooth and clear. The tarsal conjunctiva is pink, smooth, thin and transparent;
there are normally large, deep-lying blood vessels that run vertically over its entire area.
2.1.2 Know the appearance of TT, CO and TF The WHO simplified grading scheme  comprises five signs. For programme planning, monitoring and evaluation, three of these five signs are particularly important: trachomatous inflammation – follicular (TF), trachomatous trichiasis (TT), and corneal opacity (CO). The prevalence of TF in children aged 1–9 years is the key index for determining whether an area needs intervention with the A, F and E components of SAFE. The prevalence of TT determines the probable need for surgical services. The prevalence of CO is a (rough) measure of the burden of blindness and visual impairment due to trachoma.
At an individual level, the presence of TT means that that person needs surgery to reduce the risk that he or she will develop CO. The presence (and area) or absence of CO in a person who is about to have surgery for TT is important for determining how much the surgery will benefit that person; assessing CO at follow-up helps to determine how much benefit was obtained.
An eye can have more than one sign. When a person is examined, the presence or absence of TT is assessed first, then CO, then TF. The signs are therefore described below in that order.
Trachomatous trichiasis (TT) TT is defined as “at least one eyelash rubs on the eyeball, or evidence of recent removal of in-turned eyelashes”.
Corneal opacity (CO) CO is defined as “easily visible corneal opacity over the pupil, so dense that at least part of the pupil margin is blurred when viewed through the opacity”. Such opacities tend to cause significant visual impairment (visual acuity less than 6/18, or 0.3 vision).
Trachomatous inflammation – follicular (TF) TF is defined as “the presence of five or more follicles at least 0.5 mm in diameter in the central part of the upper tarsal conjunctiva”.
Follicles are round swellings up to 3.0 mm in diameter. They are grey or creamy and are therefore paler than the surrounding conjunctiva. Peripheral follicles (lying outside the area enclosed by the dotted line in the picture of the normal tarsal conjunctiva on the trachoma grading card) and follicles smaller than
0.5 mm in diameter do not contribute to a diagnosis of TF, since they may be normal.
TF is one of two signs of ‘active trachoma’. The other sign in the WHO simplified grading scheme is trachomatous inflammation – intense (TI), which is defined as “pronounced inflammatory thickening of the upper tarsal conjunctiva obscuring more than half the normal deep tarsal vessels”. (A person is said to have active trachoma if he or she has TF and/or TI in either eye.) The clinical appearance of TI is similar to that produced by several other eye infections. TF is therefore the sign used in preference to TI for assessing the need for a trachoma control programme and in monitoring its results.
The final sign in the WHO simplified grading scheme is trachomatous conjunctival scarring (TS), which is defined as “the presence of easily visible scars in the tarsal conjunctiva”. TS is not useful for programme purposes, as no intervention is indicated by its presence.
2.1.3 Prepare the person who is to be examined First, explain to the person who is to be examined, or their parent, the reason for the examination and what the examination will involve.
To examine an adult or an older child, you and the subject of the examination should sit or stand so that your heads are at approximately the same level. If the person is a lot shorter than you, you should sit while the subject stands. If you are both sitting, your chairs should be close enough that the subject’s knees nearly touch your chair; your knees will need to pass on either side of the subject’s.
To examine a young child, obtain the help of an assistant. This may be the child’s parent. When many children are to be examined, however, it is usually easier to have a dedicated assistant who understands your requirements and is skilled at handling children. Instruct your assistant that, if necessary, the child should be held very firmly: if the child is unable to move his or her head, arms or legs, the examination can be completed quickly and painlessly. The child should sit on the assistant’s lap facing you, with his or her back against the assistant’s front (Figure 2a). The assistant should hold the child’s head against his or her chest with one hand and hold the child’s body and arms with the other arm. If the child is uncooperative, his or her legs should be placed between the assistant’s legs to prevent kicking. Alternatively, to prevent kicking, the child can be wrapped in a large cloth.