Trachoma

Trachoma is a preventable infectious eye disease caused by repeated infections with eye strains of the bacteria Chlamydia trachomatis. It causes painful blindness in older people who have had severe active trachoma usually in childhood.

How it is spread

Trachoma occurs in areas with overcrowded housing where personal and community hygiene are difficult to maintain. The Chlamydia trachomatis bacterium is easily spread through infected eye secretions.

These secretions are passed back and forth between young children during close contact such as playing and sharing the same bedding. Flies can also spread the bacterium.

Children are the main reservoir of infection. Dirty faces are the most important risk factor in the transmission of trachoma.

Symptoms

It is important to note that active trachoma in children often causes no symptoms. Trachoma can be present even in children with clean faces. However, children with active trachoma may have red, sore, sticky eyes and nasal discharge.

Follicles and inflammation under the upper eyelids are the hallmarks of active trachoma.

As trachoma progresses, scarring develops under the eyelids. The eyelashes turn in and rub on the cornea. This abnormal condition is called trichiasis. This may be painful and will cause corneal scarring, followed by visual loss and then blindness.

Who is at risk

Aboriginal people in remote Australia are most at risk of developing trachoma. Young children, especially those with poor personal and family hygiene practices are at the highest risk.

Australia is the only developed country with blinding trachoma. Trachoma is a common cause of blindness in Aboriginal adults.

Active trachoma is usually seen in young children and adolescents. The highest rates of disease are found in children aged 3-8 years.

The cycle of repeated active infection and resolution occurs over many years. Teenagers and adults have the scarring stage of trachoma. Without treatment, adults may develop trichiasis which can ultimately lead to blindness.

Infectious period

Trachoma is highly infectious in its early stage and may be infectious intermittently as long as active trachoma infection persists. People who are at risk experience repeated episodes of infection.

Adults and those without clinical signs may still have episodes of infection and be infectious.

Treatment

The antibiotic azithromycin is used to treat active trachoma. A single dose is given, and may be repeated in 6 to 12 months.

Azithromycin is the recommended treatment for all people diagnosed with trachoma as well as their contacts. A contact is anyone who is living and/or sleeping in the same house as a person with trachoma.  If the person lives or sleeps in multiple households, then all members of each household are regarded as contacts.

If there is a high rate of trachoma in a community, then all Aboriginal members of the community should be treated. Indigenous adults over 40 years of age from communities in which trachoma is endemic should be screened annually for trichiasis. Additionally, adults who complain of a sore eye need to be examined for trichiasis. Health services need to ensure that a process is in place for timely surgical referral and treatment of people with trichiasis.

The World Health Organisation and the Communicable Disease Network Australia recommend the SAFE strategy:

• Surgery – surgical correction for trichiasis
• Antibiotics - azithromycin for cases of active trachoma and their contacts (that is all household members)
• Facial cleanliness – promote clean faces to reduce spread of infection
• Environmental improvements – Improve overcrowding, water and sanitation facilities. It is especially important to address barriers to face washing.

These 4 actions are aimed at eliminating trachoma by reducing the risk and frequency of transmission and preventing trichiasis with surgery.

Prevention

The promotion of clean faces in children along with environmental improvements to reduce overcrowding and to support good hygiene practices are the best ways to control trachoma.

Information for health professionals

To find out more go to the NT Health website.

Contact

For more information contact the Centre for Disease Control or the Northern Territory Trachoma Program.