Epidemiology of gonorrhoea


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A sexually transmitted infection caused by a Gram-negative diplococcus.

Infects mucous membranes of the genital tract, rectum, pharynx and eyes

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  • Neisser was an undistinguished student who had to repeat his chemistry exams Followed by the discovery of treponema pallidum (cause of syphillis in 1905) There was no treatment of gonorrhoea until the discovery of penicillin, however ophthmalmia neonatorum, a conjunctivitis affecting the new born could be treated easily by the application of silver nitrate thus preventing a common cause of blindness. In 1943 penicillin was being tried in a British field hospital in North Africa. It was in desperately short supply. The urine from patients was collected and the penicillin extracted so that more people could be treated. There were two main groups of patients in the hospital. Patients with extensive infected war wounds and patients with gonorrhoea. The MRC had sent the drug for trial in patients with war wounds but it was noticed that the drug was effective in gonorrhoea. You do not have enough penicillin for everybody, who would you treat? Option 1. The men with war wounds who might die if not treated. Option 2. The men who had ignored orders and gone to the local brothels. War wounds versus self inflicted disease. Life threatening infected war wounds versus crippling chronic gonorrhoea. The fact that there is a war on and penicillin cures gonorrhoea - you can rapidly send men back to their units. War wounds have a prolonged convalescence and the patient may never be fit again for military service. The decision went as far as the War Cabinet. Churchill chose to treat the men with gonorrhoea.
  • 1864- Contagious Disease Act- This legislation allowed policeman to arrest prostitutes in ports and army towns and bring them in to have compulsory checks for venereal disease. If the women were suffering from sexually transmitted diseases they were placed in a locked hospital until cured. It was claimed that this was the best way to protect men from infected women. Many of the women arrested were not prostitutes but they still were forced to go to the police station to undergo a humiliating medical examination. Repealed in 1886. The biggest initiative came with the appointment in 1913 of a Royal Commission on Venereal Diseases which submitted its final report in 1916 – mid-way through the First World War and at a time of increased incidence of the very diseases it had been formed to consider. The report estimated that at least a tenth of the urban population in Britain was infected with syphilis, and many more infected with gonorrhoea The Commission shied away from advocating a system of compulsory notification, but recommended free examination and treatment, and the Local Government Board implemented this through the provision of grant to local authorities to open free clinics. Following on from the report, the 1917 Venereal Diseases Act made it illegal for anyone other than legally qualified medical practitioners to give advice or medication for venereal diseases. At the turn of the century charlatans commonly advertised treatment of STD but were using laudanum(mixture of gin and opium). The act also protects the patient’s confidentiality.
  • Since the beginning of the 20th century, peaks of reported cases of gonorrhea in developed countries occurred during World Wars 1 and 2, and following the "sexual liberation" of the late 1960s and early 1970s. Thereafter, there has been a sharp decline in the incidence of this disease in almost all western countries. This decline occurred first in countries of Northern Europe. For instance, in Sweden, gonorrhea incidence (reported cases) decreased from 487 per 100,000 in 1970 to 31 per 100,000 in 1987, and was below 10 per 100,000 in 1994. In parallel with this decline, there has been a steady reduction in the male:female ratio of reported cases. This early decline in incidence, as well as the reduction in the male:female ratio, can be attributed, at least in part, to improved screening programs for women and enhanced partner notification of STD cases.
  • Gonorrhoea has been a notifiable disease in Sweden since 1925. The incidence of gonorrhoea peaked in Sweden in 1970 with an annual incidence of almost 500 per 100 000 population. Levels of gonorrhoea reached an all-time low in 1996 with 2.4 cases per 100,000. In the early 1990s it was thought that the disease would be completely eradicated. However incidence has risen since 1996. Initially this was thought to be die to imported cases, but studies have shown there to be a rise in domestic cases also.
  • Epidemiology of gonorrhoea

    1. 1. Epidemiology of gonorrhoea Josep Vidal Alaball, Anne Marie Cunningham, David Tucker, Suzanne Mckeown, Karen Gully and Paul Scott 23 March 2004
    2. 2. Neisseria Gonorrhoea <ul><li>A sexually transmitted infection caused by a Gram-negative diplococcus. </li></ul><ul><li>  Infects mucous membranes of the genital tract, rectum, pharynx and eyes. </li></ul><ul><li>May present with discharge or dysuria. </li></ul><ul><li>50% of women have no symptoms. </li></ul><ul><li>Homosexual men may have asymptomatic rectal infection. </li></ul>
    3. 3. Age and sex <ul><li>Majority of gonococcal infections diagnosed among: </li></ul><ul><li>Female aged 16-19 years (35%) </li></ul><ul><li>Male heterosexual aged 25-34 years (32%) </li></ul><ul><li>Men who have sex with men (MSM): 24% mainly aged 25-34 years </li></ul><ul><li>Median age of infection: </li></ul><ul><li>Female: 21 years </li></ul><ul><li>Male heterosexual: 25 years </li></ul><ul><li>Men who have sex with men (MSM): 30 years </li></ul>
    4. 5. graph
    5. 7. Ethnic differences <ul><li>47% total diagnoses, despite only 5% of total population </li></ul><ul><li>Mainly black ethnic groups, particularly Black Caribbeans: </li></ul><ul><ul><li>44% of total females </li></ul></ul><ul><ul><li>55% of total heterosexual males </li></ul></ul><ul><li>       </li></ul>
    6. 9. Sex workers and gonorrhoea <ul><li>Laurent, C., Seck, K., Coumba, N., Kane, T., Samb, N., Wade, A., Liegeois, F., Mboup, S., Ndoye, I. and Delaporte, E. (2003) 'Prevalence of HIV and other sexually transmitted infections, and risk behaviours in unregistered sex workers in Dakar, Senegal.' AIDS, 17, 1811-6. </li></ul><ul><li>  </li></ul>
    7. 10. <ul><li>Three-quarters of the women were found to </li></ul><ul><li>have markers for at least one infection: </li></ul><ul><li>HIV, 10% </li></ul><ul><li>Syphilis, 23.8% </li></ul><ul><li>Gonorrhea, 22.0% </li></ul><ul><li>Chlamydial infection, 20.0% </li></ul><ul><li>Trichomoniasis, 22.4% </li></ul><ul><li>Candidiasis, 19.0% </li></ul><ul><li>Bacterial vaginosis, 28.8%. </li></ul>
    8. 11. History <ul><li>Discovered in 1879 by Albert Ludwig </li></ul><ul><li>Sigesmund Neisser </li></ul><ul><li>Ophthlamia neonatorum-notifiable disease in 1914 </li></ul><ul><li>Fleming discovers penicillin in 1929 </li></ul><ul><li>MRC funds research by Florey and Chain into production of penicillin during WWII </li></ul>Anne-Marie:
    9. 12. Legislation <ul><li>1864 Contagious Diseases Act, repealed 1888 </li></ul><ul><li>1913 Royal Commission on Venereal Disease </li></ul><ul><li>1917 Venereal Diseases Act </li></ul>
    10. 17. Table 3. Estimated new cases of gonorrhoea infections (in million) in adults, 1995 and 1999 Region 1995 1999 Female Male Total Female Male Total Trend North America 0.92 0.83 1.75 0.84 0.72 1.56 F  M  P  Western Europe 0.63 0.6 1.23 0.63 0.49 1.11 F  M  P  North Africa & Middle East 0.77 0.77 1.54 0.68 0.79 1.47 F  M  P  Eastern Europe & Central Asia 1.16 1.17 2.32 1.81 1.5 3.31 F  M  P  Sub Saharan Africa 8.38 7.3 15.67 8.84 8.19 17.03 F  M  P  South and South East Asia 14.55 14.56 29.11 15.09 12.12 27.2 F  M  P  East Asia & Pacific 1.47 1.8 3.27 1.68 1.59 3.27 F  M  P  Australia & New Zealand 0.07 0.06 0.13 0.06 0.06 0.12 F  M  P  Latin America & Caribbean 3.67 3.045 7.12 4.01 3.26 7.27 F  M  P  Total 31.61 30.54 62.15 33.65 28.7 62.35 F  M  P 
    11. 21. STI Surveillance Population Demographic Behavioural
    12. 22. Large scale surveys for surveillance? <ul><li>National Survey of Sexual Attitudes and Lifestyles 1990 & 2000 </li></ul><ul><li>  </li></ul><ul><li>    Both men and women report a greater number of sexual partners (over the past five years) in 2000 than in 1990 </li></ul><ul><li>     An increase in the number of men and women reporting concurrent partnerships </li></ul><ul><li>  </li></ul><ul><li>An increase in reported consistent use of condoms but also an increase in those reporting unsafe sex </li></ul>
    13. 23. <ul><li>Increased risky behaviours are consistent with: </li></ul><ul><ul><li>Changing cohabitation patterns </li></ul></ul><ul><ul><li>  </li></ul></ul><ul><ul><li>Rising incidence of STIs </li></ul></ul><ul><li>Differences between 1990 and 2000 likely to result from: </li></ul><ul><ul><li>True change </li></ul></ul><ul><ul><li>Greater willingness to report behaviours due to: </li></ul></ul><ul><ul><ul><li>Improved survey methodology </li></ul></ul></ul><ul><ul><ul><li>More tolerant social attitudes </li></ul></ul></ul><ul><li>  </li></ul>
    14. 24. Large scale surveys for surveillance? <ul><li>Size matters for key outputs </li></ul><ul><ul><li>direct estimates </li></ul></ul><ul><ul><li>identification of highest risk populations </li></ul></ul><ul><ul><li>interpretation of trends </li></ul></ul><ul><li>   </li></ul><ul><li>Detail sacrificed for </li></ul><ul><li>  </li></ul><ul><ul><li>greater frequency </li></ul></ul><ul><ul><li>  </li></ul></ul><ul><ul><li>lower cost </li></ul></ul><ul><ul><li>less complexity </li></ul></ul>
    15. 25. <ul><li>Triennial module for national health surveys? </li></ul><ul><li>CASI sexual behaviour module </li></ul><ul><li>  </li></ul><ul><li>Probability sample </li></ul><ul><li>  </li></ul><ul><li>Large </li></ul><ul><li>  </li></ul><ul><li>Annual </li></ul><ul><li>  </li></ul><ul><li>All ages </li></ul><ul><li>  </li></ul><ul><li>Collects biological specimens - blood/urine? </li></ul>
    16. 26. <ul><li>Possible standard surveillance items suggested by the Johnson et </li></ul><ul><li>al, 2003. </li></ul><ul><li>  </li></ul><ul><li>        Age at first intercourse </li></ul><ul><li>        Condom use at first intercourse </li></ul><ul><li>  </li></ul><ul><li>        Condom use at last sex </li></ul><ul><li>  </li></ul><ul><li>        Partners in the last year </li></ul><ul><li>  </li></ul><ul><li>        Prevalence of same-sex contact </li></ul><ul><li>  </li></ul><ul><li>        Prevalence of paying for sex </li></ul>
    17. 27. Objectives <ul><li>What do we know about the variability in sexual behaviours in populations? </li></ul><ul><li>  </li></ul><ul><li>How is behaviour changing over time? </li></ul><ul><li>  </li></ul><ul><li>How does behaviour relate to STI risk (in individuals and populations) </li></ul><ul><li>  </li></ul><ul><li>What does that tell us about prevention programmes? </li></ul>
    18. 28. Diagnosis <ul><li>Screening by urinalysis </li></ul><ul><li>Syndromic management </li></ul><ul><li>Smear diagnosis (presumptive) </li></ul><ul><li>Typical Gram negative intracellular </li></ul><ul><li>diplococci on direct Gram stain smear </li></ul>
    19. 29. Culture diagnosis (presumptive) Typical colonial morphology on selective culture medium, typical Gram stain morphology, positive oxidase reaction, positive superoxol reaction.   Culture diagnosis (‘Gold standard’) Typical colonial morphology on selective culture medium, typical Gram stain morphology, positive oxidase reaction confirmed with sugar utilisation, coagglutination or anti-gonococcal fluorescent antibody testing .
    20. 30. <ul><li>Where results are unavailable at first visit </li></ul><ul><li>there is a risk of: - </li></ul><ul><li>  </li></ul><ul><li>·    Failure to return </li></ul><ul><li>·    Missed treatment </li></ul><ul><li>·    Spread of sexually transmitted disease </li></ul><ul><li>  </li></ul><ul><li>Point of contact testing can lead to more </li></ul><ul><li>sexually transmitted infections being </li></ul><ul><li>averted than by using ‘gold standard’ </li></ul><ul><li>tests. </li></ul>
    21. 31. <ul><li>The required sensitivity of a point of </li></ul><ul><li>contact test depends upon: - </li></ul><ul><li>Underlying patterns of sexual behaviour </li></ul><ul><li>Condom use </li></ul><ul><li>STI prevalence in the groups accessing services. </li></ul><ul><li>  </li></ul>
    22. 32. <ul><li>In women attending GUM clinics in the UK, there is little potential for further STI transmission. </li></ul><ul><li>  </li></ul><ul><li>The gain from point of contact testing in this setting is very low. </li></ul>
    23. 33. <ul><li>Where there is substantial risk of STI transmission, a POC test with sensitivity of 50% may prevent up to 122% more gonococcal infections than a ‘gold standard’ test (Vickerman, Watts, Alary, Mabey and Peeling, 2003). </li></ul>
    24. 34. <ul><li>However, accurate testing gives a more reliable estimate of prevalence in those investigated. </li></ul><ul><li>Meaningful comparison of prevalence rates depends upon the use of a common measure. </li></ul>
    25. 35. <ul><li>Edinburgh </li></ul><ul><li>Audit of the sensitivity of microscopic diagnosis, 1995-1999. </li></ul><ul><li>596 cases of positive cultures </li></ul><ul><li>Sensitivity </li></ul><ul><li>Females - Cervical slides 51% </li></ul><ul><li>Heterosexual Males – Urethral slides 84% </li></ul><ul><li>Homosexual men - Urethral slides 89% </li></ul><ul><li> - Rectal slides 54% </li></ul>
    26. 36. <ul><li>Certain serovars are less likely to be detected by microscopy. </li></ul><ul><li>Undetected infection is more likely to spread within the community. </li></ul><ul><li>(Manavi, Young and Clutterbuck, 2003) </li></ul>
    27. 37. Community based screening <ul><li>Urine samples </li></ul><ul><li>Mobile clinic, Louisiana (Kahn, Moseley, Thilges, Johnson and Farley, 2003) </li></ul><ul><li>High acceptability </li></ul><ul><li>2229 urine samples </li></ul><ul><li>4.9% positive </li></ul>
    28. 38. <ul><li>Baltimore STD and Behaviour Survey </li></ul><ul><li>(Zenilman, Miller, Gaydos, Rogers and </li></ul><ul><li>Turner, 2003) </li></ul><ul><li>579 Participants aged 18-35 years </li></ul><ul><li>6.7% positive for gonococcal infection </li></ul><ul><li>Positive tests repeated (using the same assay) </li></ul><ul><li>Positive predictive value 83.3% </li></ul>
    29. 39. <ul><li>There is a risk of false positive results, particularly in low prevalence populations, leading to over-treatment. </li></ul><ul><li>There is a risk of false negative results, leading to under-treatment and spread of infection. </li></ul>
    30. 40. <ul><li>Culture from different sites is essential to maximise detection. </li></ul><ul><li>Borderline test results should be repeated. </li></ul><ul><li>  </li></ul><ul><li>Data comparisons must take into account different methods of diagnosis. </li></ul><ul><li>  </li></ul><ul><li>Resource availability may dictate the accuracy and completeness of data. </li></ul>
    31. 41. Policy and strategy to tackle STIs (…in England) <ul><li>2001 The national strategy for sexual health and HIV </li></ul><ul><li>2002 Implementation Action Plan </li></ul><ul><li>2003 Toolkit for commissioning services </li></ul><ul><li>2003 Toolkit for promoting good sexual health and HIV prevention. </li></ul>
    32. 42. The national strategy and implementation action plan <ul><li>5 aims: </li></ul><ul><li> HIV + STI transmission </li></ul><ul><li>(25%  in gonorrhoea infections by 2007) </li></ul><ul><li> undiagnosed HIV + STI prevalence </li></ul><ul><li> unintended pregnancy rates </li></ul><ul><li>Improve health and social care for people with HIV </li></ul><ul><li> stigma associated with HIV AND STIs </li></ul>
    33. 43. General progress in 2003/2003 <ul><li>DH investment of £14 + million </li></ul><ul><ul><li>Improve GUM services </li></ul></ul><ul><ul><li>Roll out chlamydia screening programme </li></ul></ul><ul><ul><li>National information campaign </li></ul></ul><ul><ul><li>One stop shops (advice, contraception, GUM) </li></ul></ul><ul><ul><li>Develop service standards and workforce </li></ul></ul>
    34. 44. Implications for primary care <ul><li>PCTs to appoint sexual health lead </li></ul><ul><li>PCT plans to link with: </li></ul><ul><ul><li>Local Authority, Connexions, mental health, substance misuse, teenage pregnancy and Health Protection Agency </li></ul></ul><ul><li>Undertake needs assessment and agree local benchmarks for monitoring progress. </li></ul>
    35. 45. 3 Service Levels <ul><li>Level 1 </li></ul><ul><ul><li>Mostly non-invasive, but will also involve: </li></ul></ul><ul><ul><ul><li>Hep B screening </li></ul></ul></ul><ul><ul><ul><li>Chlamydia screening </li></ul></ul></ul><ul><ul><ul><li>HIV testing and counselling </li></ul></ul></ul><ul><ul><ul><li>Testing symptomatic women for STIs </li></ul></ul></ul><ul><ul><ul><li>Assessment and referral for men with symptomatic STI’s </li></ul></ul></ul><ul><ul><li>Provided by primary care practices by 2013 </li></ul></ul>
    36. 46. <ul><li>Level 2 and 3 </li></ul><ul><ul><li>Require additional skills and facilities </li></ul></ul><ul><ul><li>Provided by local networks of sexual health services </li></ul></ul><ul><ul><li>mainstreamed. </li></ul></ul>