MINISTRY OF HEALTH

Neglected Tropical Diseases Control Program Tanzania

Trachoma
Last edit: 2018-11-14 12:07:26.
HIGHLIGHTS
In Tanzania mainland, Trachoma Baseline surveys were conducted between 2004-6 where 50 districts were found to be trachoma endemic, with active trachoma in all 50 districts. The prevalence of active trachoma was 25.4%, whereas prevalence of Trachomatous Trichiasis (TT) was found to be 2.7% with TT backlog estimate of 167,000 cases countrywide. In total Tanzania was estimated to have 12.5 million people at risk for trachoma.

In Tanzania mainland the trachoma mapping completed, with a total of 71 Trachoma endemic districts. SAFE interventions have been implemented and currently the country remains with only 8 districts needing SAFE interventions as of October 2018. The remaining 63 districts have stopped Zithromax MDA, and are continuing with surveillance surveys and F&E interventions. The current Trichiasis backlog has declined to 17,010 people and community based TT surgical services is implemented in all the districts with TT prevalence above 0.2% threshold as per WHO guideline.

WHAT IS TRACHOMA
Trachoma is among the major causes of preventable blindness. The disease mainly affects rural populations with limited access to health care, clean water, and poor environmental sanitation.
In affected communities, infection is often first encountered in infancy or childhood. With repeated infection over many years, the cumulative effect of many inflammatory episodes may cause the upper eyelid to turn inwards, so that the eyelashes rub on the eyeball, resulting in intense pain and scarring of the front of the eye. This is called trachomatous trichiasis, and ultimately leads to irreversible blindness.

Symptoms
Some among the signs and symptoms of trachoma usually affect both eyes and may include: -
  • Mild itching and irritation of the eyes and eyelids
  • Discharge from the eyes containing mucus or pus
  • Eyelid swelling
  • Light sensitivity (photophobia)
  • Eye pain

Diagnosis
Trachoma disease is usually clinically diagnosed. People are examined for clinical signs through the use of magnifiers (loupes). In most early stages, infection does not present visible signs of the disease. However, repeated infections cause scarring of the conjunctiva and it is during this phase that infected individuals get the feeling of irritation.

The WHO grading system for trachoma classifies the disease in 5 grades:
  • Trachomatous Inflammation – Follicular (TF) - which mostly requires topical treatment.
  • Trachomatous Inflammation – Intense (TI) - during which topical and systemic treatments are considered.
  • Trachomatous Scarring (TS) - when scars are visible as in the tarsal conjunctiva and which may obscure tarsal blood vessels.
  • Trachomatous Trichiasis (TT) - when an individual is referred for eyelid surgery; and
  • Corneal Opacity - a stage during which a person is irreversibly blind.

Clinical characteristics
In areas where trachoma is endemic, active (inflammatory) trachoma is common among preschool-aged children, with prevalence rates which can be as high as 60-90%. Infection becomes less frequent and shorter in duration with increasing age.
Infection is usually acquired through living in close proximity to others with active disease, and the family is the principal unit for transmission. An individual’s immune system can clear a single episode of infection, but in endemic communities, re-acquisition of the organism occurs frequently.
After years of repeated infection, the inside of the eyelid can become so severely scarred (trachomatous conjunctival scarring) that it turns inwards and causes the eye-lashes to rub against the eyeball (trachomatous trichiasis) resulting in constant pain and light intolerance; this and other alterations of the eye can lead to the scarring of the cornea. Left untreated, this condition leads to the formation of irreversible opacities, with resulting visual impairment or blindness. The age at which this occurs depends on several factors including local transmission intensity. In very highly endemic communities, it can occur in childhood, though onset between the ages of 30 and 40 years is more typical.

Morbidity
Visual impairment or blindness results in a worsening of the life experience of affected individuals and their families, who are normally already amongst the poorest of the poor. Women are blinded 2 to 3 times more often than men, probably due to their close contact with infected children and their resulting greater frequency of infection episodes themselves.
Environmental risk factors influencing the transmission of the disease include:
  •  poor hygiene;
  • living/sleeping with domestic animals;
  • water shortage; and
  • inadequate latrines and sanitation facilities.

EPIDEMIOLOGY IN TANZANIA

WHO’s goal is to eliminate trachoma as a public health problem by the year 2020. Elimination of trachoma as a public-health problem is defined as a reduction in the prevalence of trichiasis “unknown to the health system” to less than 1 case per 1000 total population (“known” cases are those in whom trichiasis has recurred after surgery, those who refuse surgery, or those yet to undergo surgery whose surgical date is set); and a reduction in the prevalence of the active trachoma sign “TF” in children aged 1–9 years to less than 5%.
In Tanzania, MDA started in 1999 and has been underway in many trachoma endemic districts. Trachoma is mainly endemic in 71 districts and currently a total of 63 (89% of eligible districts) have stopped MDA following impact surveys that showed elimination of TF (<5%) had been attained .

TRANSMISSION
Trachoma is a bacterial infection that affects eyes. It is transmitted through flies which have been in contact with the eyes and noses of infected people It can also be passed on by handling infected items, such as handkerchief and clothes. Infection is usually acquired when living in close proximity to others with active disease, and the family is the main setting for transmission.

ELIMINATION CONTROL EFFORTS IN TANZANIA
Trachoma elimination efforts in Tanzania are implemented as an integrated approach under the National Neglected Tropical Diseases Control Programme (NTDCP) since its launch in year 2009.  The program implements Trachoma elimination efforts by following the WHO SAFE strategy as recommended intervention to tackle Trachoma in the country. SAFE is an acronym for;
  • Surgery for trachomatous Trichiasis
  • Antibiotics (Azithromycin Mass Drug Administration MDA)
  • Facial cleanliness
  • Environmental improvement, particularly improved access to water and sanitation.

TRICHIASIS SURGICAL SERVICES
As per WHO guideline elimination of Trichiasis will be considered if Trachomatous Trichiasis is below 0.2% in a population of people aged 15 years and above. Tanzania program is following WHO guideline and currently implementing trichiasis surgical camps in 46 districts which have prevalence of above 0.2% in a population of people aged 15 years and above. TT surgical services are implemented through two approach; Outreach camps and static sites. TT backlog during baseline was found to be estimate of 167,000 cases countrywide and currently the backlog is 17,010.

ANTIBIOTICS
Trachoma is regarded to be endemic in a district after conducting a WHO population survey and found Trachoma Inflammation Follicular (TF) to be above 0.5%. This is where Mass drug administration for Trachoma should be undertaken by using house to house intervention. In Tanzania Mapping for Trachoma has been completed in all 71 known endemic district for Trachoma. 63 out of 71 districts have stopped MDA and they are now undergoing surveillance. MDA is conducted currently in 8 districts only

FACIAL CLEANLINESS AND ENVIRONMENTAL IMPROVEMENT
Facial Cleanliness and environmental Improvement is a very important component for the sustainable progress towards Trachoma elimination. These WASH activities in Tanzania are mainly done in all districts with TF above WHO elimination thresholds.  There are two main approach of F & E as far as Trachoma is concerned and these are mainly: Community WASH programs and School WASH program (SWASH). F and E activities are currently embedded in the National Sanitation Campaign.

POLICY

RESOURCES
1.    Trachoma Survey Baseline survey reports
2.    TAP document
3.    Masterplan document
4.    TT Only survey reports
5.    TIS and TSS survey reports