Challenges for the Venereologist in the st 21 Century
Dr David Rowen, Royal South Hants Hospital, Southampton
Challenges
Microbial drug resistance Neisseria gonorrhoeae Chlamydia Mycoplasma
Implementation of HPV vaccination schemes
Dr David Rowen, Royal South Hants Hospital, Southampton
Neisseria gonorrhoeae
Standard treatments should cure 95% of infections Resistance rates of >5% should lead to change in treatment protocol. Correlation between susceptibility and outcome of treatment is good but not absolute Duration of carriage is site specific Dr David Rowen, Royal South Hants Hospital, Southampton
Neisseria gonorrhoeae
Penicillin resistance is common Penicillinase producing N.gonorrhoeae (PPNG) Chromosomally mediated resistance (CMR) develops incrementally; broad range of MIC
Marked increase in PPNG in early 90’s but this is decreasing in many places Many centres report >80% of isolates have CMR Dr David Rowen, Royal South Hants Hospital, Southampton
Quinalones ď Ž
ď Ž
Resistance has emerged relatively recently but first reported in 1992 >70% of isolates from SE Asia and Philippines are resistant
Dr David Rowen, Royal South Hants Hospital, Southampton
Cephalosporin Resistance
3rd generation Cephalosporins unaffected by β lactamase of PPNG Resistance is chromosomally mediated Shift to right in MICs resulting in increasing doses of Ceftriaxone being used Cefixime can no longer be recommended as MICs beyond break point whereby there is >95% cure rate Dr David Rowen, Royal South Hants Hospital, Southampton
Treatment
Cheap treatment options have been lost Expensive options may have limited life Spectinomycin difficult to obtain Combination treatments Gentamicin+Azithromycin
Gemifloxacin+Azithromycin Excellent
cure rates but high rate of S/E
Dr David Rowen, Royal South Hants Hospital, Southampton
Chlamydia
Treatment failure with Azithromycin well documented but at low level Some failure thought to be due to absorption issues Resistance testing not widely available and reliability has been questioned However evidence of emerging resistance to macrolides Dr David Rowen, Royal South Hants Hospital, Southampton
Mycoplasma
PCR test available but rarely requested Often NSU/cervicitis treated with single dose of Azithromycin This selects out resistant strains of Mycoplasma Longer courses of Azithromycin or Doxycycline may prevent this Moxifloxacin is active against Azithromycin resistant strains Dr David Rowen, Royal South Hants Hospital, Southampton
HPV Vaccines
Proven efficacy in preventing genital warts and high grade dysplasia, should prevent HPV type 16 and 18 associated malignancy Significant cost implications in vaccination progrmmes: Quad vaccine cost £240 in UK Ethical issues: vaccine against STI What strategies can be applied to resource poor countries Dr David Rowen, Royal South Hants Hospital, Southampton
HPV Vaccines: cost issues
Restrict vaccination to girls Does prevent warts in men but ~80% coverage needed Will not impact of homosexual men in whom AIN is more common
Shorter courses of vaccine
Little evidence to support long term efficacy
Use bivalent vaccine which is cheaper
Prevents high grade dysplasia but not warts
Dr David Rowen, Royal South Hants Hospital, Southampton
HPV Vaccines: cost issues
Generic vaccines Patents
have long time to run Is the technology available?
Charitable vaccination programmes Government sponsored programmes WHO programmes Subsidized costs for resource poor countries
Dr David Rowen, Royal South Hants Hospital, Southampton
HPV vaccines: logistics
How do we deliver vaccine to large populations especially in rural communities
Mobile clinics staffed by minimally qualified workers
How can we be sure that patients receive correct number of inoculations? Robust but inexpensive IT support Patient incentives ?cash
Dr David Rowen, Royal South Hants Hospital, Southampton
Ethical Issues
More acceptable as anti-cancer vaccine Working with Temples, Mosques, Gudwaras and churches may overcome some of the perceived ethical concerns Women more open to concept of vaccination than men Is it ethical to pay patients to be inoculated? Dr David Rowen, Royal South Hants Hospital, Southampton