Chlamydia is the name given to a distinct genus of bacteria, which causes a wide spectrum of human illness.

Three species (C.pneumoniae, C.trachomatis and C.psittaci) are acquired by different means and cause extensive health problems. They differ from other kinds of bacteria in two important respects: they are considerably smaller and they behave more like viruses than bacteria. Chlamydiae can’t exist outside a host cell.

Chlamydia trachomatis causes genital and ocular infections in children and young adults and is spread via close contact, usually sexual. In children, flies may pass C.trachomatis, from eye to eye. Babies may acquire infection from mothers during birth, affecting their eyes, respiratory and genital tracts. In adults, the usual mode of infection is through sexual contact, often in association with other sexually transmitted infections. C.trachomatis is the most commonly notified STI in Victoria.

Eye infections

The incubation period is 7-14 days.

Eye infections in children may progress to trachoma and blindness in adults.

Genital infections in adults are commonly asymptomatic, especially in women.

Women may have cervicitis, urethritis, vaginitis or infection of Bartholin’s glands. C.trachomatis causes salpingitis and is a major cause of infertility and ectopic pregnancy.
Men often have a urethritis resembling gonorrhoea, an acute epididymitis or, in homosexual males, proctitis.
Both sexes (mainly males) may develop lymphogranuloma venereum(LGV), with fever, chills and headaches. Males develop inguinal lymphadenopathy and females experience complications such as rectovaginal fistula or proctitis. Check your Better Health Channel for more details.

Urethral discharge

Obligation
Medical practitioners in Victoria have a statutory obligation under the Children, Youth and Families Act 2005 to notify the department’s Child Protection service if they believe that a child is in need of protection on the basis of sexual abuse.
Child Protection Crisis Line 13 12 78

Chlamydia pneumoniae causes disease in children and young adults and is spread via respiratory secretions from person to person. Up to 50% of the adult population has evidence of past infection. In a Melbourne study, 10 per cent of cases of community-acquired pneumonia were due to this pathogens.

The incubation period is approximately 5-10 days.

Community acquired pneumonia

The disease is often mild, but may present as pharyngitis, sinusitis, pneumonia or bronchitis. The cough may be prolonged and precipitate asthma. C. pneumoniae has also been implicated in atherosclerosis and heart disease, arthritis and Alzheimer’s disease, but this is not proven.
See Victorian Government Blue Book for more details.

Chlamydia psittaci has many serological types and is commonly found in domestic and feral animals, especially birds.
They are particularly infectious to humans (germs are swallowed or inhaled) causing two protracted clinical illnesses called psittacosis (or parrot fever):

1. A flu-like disease, with fever, headache, nonproductive cough, results in an ‘atypical pneumonia’, and
2. A ‘typhoidal’ illness with similar features, but without the cough.

Check your Better Health Channel for more details.

Lymphogranuloma venereum is caused by a strain of chlamydia and is commonest in parts of Asia, Africa, and South and Central America.

In Europe and North America the bacterial infection has started to spread among gay men in the Netherlands, France and the UK.  Recent cases have appeared in Sweden.
In January 2004, public health officials in the Netherlands noted an outbreak of LGV proctitis cases among men who have sex with men. Since then, cases have been reported from several European countries, the United States of America and Canada.

Vaccine Information
Because of its biology, a vaccine against chlamydia sp. is very difficult to achieve. Several have been developed but produced only short-term protection.
Some vaccines have been developed for use in animals.

Infections with Chlamydia sp. are usually treated with antibiotics, such as tetracycline, erythromycin or roxithromycin.