Guidelines for Elimination of Blinding Trachoma

Recommendations from World Health Organization Global Scientific and Informal Meetings

Sheila West, PhDDana Center for Preventive Ophthalmology

Wilmer Eye InstituteBaltimore MD

Background

1997: WHO establishes the Global Alliance for the Elimination of Blinding Trachoma by 2020 (GET2020)

1998: World Health Assembly signs resolution endorsing the Alliance and encourages countries to eliminate trachoma (WHA 51.11)

What is meant by Elimination?

Trachoma Signs

Follicular Trachoma: TF

Intense Trachoma : TI

Scarring Trachoma: TS

Trachomatous Trichiasis: TT

Corneal Opacity: CO

Ultimate Intervention Goals

Prevalence of TF <5% in 1-9 year olds

Prevalence of TT is <0.1% in pop’n

Intervention: SAFE

“S” : Surgery targets TT-prevention of immediate blindness

“AFE” : Antibiotic, Facial cleanliness, environmental change: Targets active trachoma, by reduction of community pool of infection, and efforts to reduce transmission, re-emergencePrevention of blindness in long term

How do we operationalize UIGS

District100,00-250,000 people

F and E for at least 3 years, targeted A

AFE for at least 3 years then impact

survey

No need for AFE

Mapping/Baseline Survey

<5% TF1-9 yo

>10% TF1-9 yo

5-9% TF1-9 yo

Updates to Operationalization

District

IF: there is some evidence that trachoma is widespread and highly endemic

THEN: a survey at super-district (regional) can be conducted

BUT: if survey results are TF<10%, then district level data will be needed to plan a programme

Updates to Operationalization

District100,00-250,000 people

AFE for at least 3 years then impact

survey

Mapping/Baseline Survey

>10% TF1-9 yo

IF: If prevalence is ≥30%, Impact surveys non informativebefore 5 years of AFE

Aim for 100% coverageDo not have interrupted treatment

How do we declare reaching UIG?

District

No need for AFE

Impact/Outcome Survey

<5% TF1-9 yo

0 1 2 3 4 5 6 7 8 9 10 110

0.05

0.1

0.15

0.2

0.25

Proportion of villages at each prevalence when mean=<5%

Proportion of villages at each prevalence when mean=<5% % villages

Prevalence of Trachoma

How do we declare reaching UIG?

District

Survey at SUB district level

Impact/Outcome Survey

<5% TF1-9 yo

5-9% TF 1-9 yo

>10% TF 1-9 yoAFE for at least 3 years

then impact survey

5-9% TF 1-9 yo F and E for at least 3 years, targeted A

<5% TF1-9 yo F and E, no A

If all <5%, declare UIG

Surveys at Sub District Level

Sub district: Stratification to make units more homogeneous for trachoma

-geographical information on hotspots-absence of infrastructure suggesting higher rates-sum of # of sub-units=district

Cannot be smaller than 3 villages

Survey precision is 4% +/- 2%

Surgery UIG: <1/1,000 TT pop’n

2005 WHO Working Group recommendation for elimination

“Satisfactory implementation of a program to reduce the prevalence of trachomatous trichiasis through identification and surgical management through the health system, with a commitment to reach the Ultimate Intervention Goal of less than 1 case of TT (refusals, recurrences, and incident cases) per 1,000 population”

Operationalize UIG for Surgery

At district level, <1/1,000 total population of TT cases unknown to health system

“known”: operated, refusals, recurrent cases, listed but not yet operated

“unknown”: in population and not recorded by health system

Health system is able to identify and manage incident TT cases

Report recurrence rate as part of HIS with a target of recurrence <10% at one year

Activities After UIGs are Met

Surveillance Documents for Elimination

• Surveys to document elimination

1. Sub district surveys where TF <5%

2. Demonstrate sustained reduction of TF at least 3 years after A stopped

• Evidence that district TT is <1/1,000 pop’n &health system is able to detect, provide treatment and follow up TT cases

• Evidence of surveillance activities to detect and respond to resurgent TF and incident TT

Surveys reveal TF<5%A can be stopped

Surveys revealSustained TF<5%

A activities stop

Create reporting network,plan surveillance activities,test in early success areas

Verify reports Verify response if new surge found

1 yr 2 yr 3 yr

Implement surveillance activities

Timeline for Elimination

1. Monitor the prevalence of TF to detect and respond to potential resurgence

2. Ensure that routine eye care services are operating incident and recurrent TT cases and monitoring incidence to detect any unknown cases

Objectives of Surveillance System

• Select 2 communities per district per year biased to the least developed and suspected most endemic

Examine all school entrance-aged children where attendance is >90% and there is no gender bias

Examine a minimum of 50 children in the community (5±2 years), but if feasible examine all

Monitor the prevalence of TF to detect and respond to potential resurgence

• Respond to a finding of >5% TF in any community-Examine all children aged 1-9 years and treat TF

-If >5% TF in all 1-9 year olds, assess AFE coverage and treat community

-Examine school entrance aged children in all communities in the surrounding sub-district

-If >5% TF in sub-district re-implement AFE for 3 years and assess TF in other sub-districts to determine whether district warrants AFE

Monitor the prevalence of TF to detect and respond to potential resurgence

• Ongoing collection and review of TT surgical output data and recurrence rates

• Incorporate TT into National Health Information Management System or similar national surveillance system

• In each community assessed for TF, examine adults aged 40 years and above for TT– Classify cases as to known or unknown to health system

Ensure that routine eye care services are operating incident and recurrent TT cases and monitoring incidence to detect any increase in blinding disease

ConclusionsWHO guidelines evolve, in response to new data, concerns

Basic rules-SAFE is recommended control strategy

-Map at district (special case: region)to document need

-Surgery: implement surgical program to meet needs by 2020, with documentation of recurrence, plans

-Implement for 3-5 years and do impact survey at district level

-If impact survey suggest <10%TF, do impact survey at sub-district level and follow guidelines

-Meet UIGs, start surveillance

Push for 2020!