Infectious diseasesepidemiology and surveillance

Page content: Victorian statutory requirement | Infectious agent | Identification | Incubation period | Public health significance & occurrence | Reservoir | Mode of transmission | Period of communicability | Susceptibility & resistance | Control measures | Outbreak measures | Additional sources of information

Victorian statutory requirement

Gonococcal infection (Group C disease) must be notified in writing within five days of diagnosis.

Specific information must be notified under the Public Health and Wellbeing Regulations 2009. To maintain confidentiality, only the name code (first two letters of the surname followed by the first two letters of the first name) is required. A questionnaire is sent to the diagnosing doctor to collect additional information on the case that is essential for detecting disease trends and informing policy development.

Medical practitioners have a statutory obligation under the Children and Young Persons Act 1989 to notify the Department of Human Services Child Protection Service if they believe that a child is in need of protection on the basis of sexual abuse.

Infectious agent

Neisseria gonorrhoeae

Identification

Clinical features
Infections with N. gonorrhoeae may present with a number of clinical syndromes.

The most common presenting symptom in males is a painful purulent urethral discharge. If left untreated, complications may include epididymitis, prostatitis and urethral stricture. Anorectal infection is more common in homosexual males and is usually asymptomatic. It may cause pruritis, tenesmus and discharge. Pharyngeal infection is usually asymptomatic.

In females, an initial urethritis or cervicitis occurs a few days after exposure. It is frequently mild and passes unnoticed. Females may have abnormal vaginal discharge and post-coital bleeding. Later, pelvic inflammatory disease may develop. Pelvic inflammatory disease may cause ectopic pregnancy, infertility or chronic pelvic pain.

Conjunctivitis can occur in neonates and rarely in adults. It may cause blindness if not rapidly and adequately treated.

Septicaemia and septic arthritis are rare complications.

Method of diagnosis
Swabs taken from the urethra, cervix, pharynx, rectum or other site should be rolled onto a slide first and then sent to the laboratory in an appropriate transport medium.

The following tests can be performed on swabs and smears taken from the site of infection:

• Gram stain on discharges smeared on the slide.
• culture on both selective and non-selective media should be used. Culture of N. gonorrhoeae provides definitive diagnosis, and isolates provide valuable information on patterns of antibiotic resistance and other epidemiological markers.
• nucleic acid testing can be performed on cervical and urethral swabs and urine. In women, PCR testing of urine is less sensitive than PCR testing on endocervical swab specimens. In cases diagnosed by PCR, further specimens should be obtained if possible for culture to allow monitoring of antibiotic resistance.

Co-infection with Chlamydia trachomatis sometimes occurs, particularly in imported cases. Screening for other sexually transmissible infections such as chlamydia should be considered when testing for N. gonorrhoeae.

Incubation period

The incubation period is usually two to seven days.

Public health significance & occurrence

Gonorrhoea is common worldwide and affects both sexes. Infection may be symptomatic or asymptomatic. Infections of the cervix, anus and throat usually cause no symptoms. Gonorrhoea can have acute and chronic sequelae.

Strains of gonococci resistant to penicillin are common and widespread. Resistance to fluoroquinolone antibiotics such as ciprofloxacin is common among isolates from infections acquired in Asia. Ciprofloxacin resistance in gonococcal isolates in Victoria is increasing.

Gonorrhoea may increase susceptibility to the sexual acquisition of HIV infection and increase HIV infectiousness.

Other serious complications such as blindness from neonatal conjunctival infection and the various complications of pelvic inflammatory disease are currently rare in Victoria. The rate of notified cases of gonorrhoea increased in Victoria in the late 1990s to a level not seen since the mid 1980s. The increase involved men who have sex with men who comprised approximately two thirds of cases, and also heterosexual men. A similar phenomenon was noted elsewhere in Australia and overseas. This increase has been sustained in Victoria.

Reservoir

Humans.

Mode of transmission

Gonorrhoea is transmitted by contact with exudates from mucous membranes of infected people, almost always as the result of sexual activity.

Gonococcal conjunctivitis can occur in neonates who have had contact with the mothers infected birth canal during childbirth.

Period of communicability

Communicability may extend for months in untreated individuals.

Susceptibility & resistance

Everyone is susceptible to infection.

Control measures

Preventive measures
Preventative measures include education about safe sex practices including use of condoms and early detection of infection by testing of those at risk.

Control of case
Ceftriaxone plus azithromycin or doxycycline (to cover co-existing chlamydial infection), are used to treat gonorrhoea. Ciprofloxacin can be used as an alternative to ceftriaxone when a sensitive strain has been identified. Advice on the clinical management of patients with gonococcal infection can be found in Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited) and the National management guidelines for sexually transmissible infections (Venereology Society of Victoria, 2002).

Specialist consultation should be sought for complicated or disseminated infections and for infection during pregnancy.

Control of contacts
Sexual partners of individuals with gonorrhoea should be examined and investigated then treated empirically.

Contact tracing assistance can be provided by the Departments partner notification officers (03) 9347 1899.

Control of environment
Not applicable.

Outbreak measures

Not applicable.

Additional sources of information

• Australian Government Department of Health and Family Services 1997, Contact tracing manual a practical handbook for health care providers managing people with HIV, viral hepatitis, other STDs and HIV-related tuberculosis.
• Centers for Disease Control and Prevention 2002, Sexually transmitted diseases treatment guidelines 2002, Morbidity and Mortality Weekly Report, vol. 51 (RR06), pp.180
  www.cdc.gov/mmwr
• Crotchfelt, KA, Welsh, LE, DeBonville, D, Rosenstraus, M & Quinn, TC 1997, Detection of Neisseria gonorrhoeae and Chlamydia trachomatis in genitourinary specimens form men and women by a co-amplification PCR assay, Journal of Clinical Microbiology, vol. 35, no. 6, pp. 153640.
• Fleming, DT & Wasserheit, JN 1999, From epidemiological synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection, Sexually Transmissible Infections, vol. 73, pp. 317.
• Venereology Society of Victoria 2002, National management guidelines for sexually transmissible infections, Venereology Society of Victoria
  www.mshc.org.au