We have heard a lot about ‘super gonorrhoea’ this year. Basically, when we say ‘super gonorrhoea’ we mean ‘gonorrhoea superbug’. These are extensively drug-resistant gonorrhoea with high-level resistance to the current recommended treatment for gonorrhoea (ceftriaxone and azithromycin) including resistance to penicillin, sulphonamides, tetracycline, fluoroquinolones, macrolides. Gonorrhea “superbug” had been reported by several countries including France, Japan and Spain, and this year also in UK and Australia.
The current situation of gonorrhoea and resistance to current treatment for gonorrhoea
Neisseria gonorrhoeae is the second most common bacterial sexually transmitted infection (STI) and results in substantial morbidity and a huge economic cost worldwide. The World Health Organization (WHO) estimates that in 2012, 78 million new cases occurred among adolescents and adults aged 15–49 years worldwide with a global incidence rate of 19 per 1000 females and 24 per 1000 males, with the highest number of incidences occurring the WHO Western Pacific and African Regions.
Antimicrobial resistance (AMR) in gonorrhoea actually appeared shortly after the introduction of antimicrobials at the beginning of the 20th century. Resistance has continued to expand since then. In countries where appropriate and quality-assured surveillance is in place, there are rising trends in decreased susceptibility and increased resistance in N. gonorrhoeae to the “last line” of antibiotics (cefixime and ceftriaxone).
What is causing resistance to gonorrhoea?
There are really 5 reasons for the rise of resistant gonorrhoea.
Unrestricted access to antimicrobials
Inappropriate selection and overuse of antibiotics
Suboptimal quality of antibiotics
Inherent genetic mutations within the organism which have contributed to the development of a pattern of resistance in N. gonorrhoeae
Extra genital infections – anorectal and pharyngeal – particularly affect key populations such as men who have sex with men. This may also play an important role in the development of resistant strains as N. gonorrhoeae interacts and exchanges genetic material with other co-infections in these anatomical sites
As levels of AMR and resistant infections are on the rise globally, we should expect to see an increase in resistance to other STIs. It is possible that we will have ‘super’ syphilis or ‘super’ chlamydia in the near future. There are risks that resistance could be seen in other STIs. In fact, we’re already seeing it. Although the first-line treatment of Benzathine penicillin remains highly effective, there has been evidence of resistance to azithromycin, commonly used as an alternative treatment for syphilis and other common infections.
There have been no reported cases of ‘super’ syphilis. There is, however, increasing resistance to Mycoplasma genitalium, a common STI that causes urethral discharge, and a common symptom of gonorrhoea and chlamydial infection as well. Luckily, there have been no reports yet of resistance to the treatment of chlamydia.
What happens if gonorrhoea is not treated effectively (untreatable)?
When we talk about the risks of ineffectively-treated gonococcal infections, there are really three main areas of concern.
Reproductive Implications
Gonococcal infections have critical implications for reproductive, maternal and newborn health including:
a five-fold increase of HIV transmission
infertility, with its cultural and social implications
inflammation, leading to acute and chronic lower abdominal pain in women
ectopic pregnancy and maternal death
first-trimester abortion; and
severe neonatal eye infections that may lead to blindness
Financial Implications
Separate from the growing severity of medical risks, gonococcal infections represent an enormous potential financial cost both for individuals and governments. Based on the 2013 global estimates of incident gonococcal infections, approximately 300 000 healthy lives would be lost yearly due to infections, with the burden of disease estimated to increase further. There is a real worry as we see both the number of people becoming infected and a rise in the number of people with long-term complications associated with gonococcal infections.
Spread of disease
The emergence of different forms of resistance in N. gonorrhoea is often followed by a rapid spread of the disease. The effect of this is felt in all countries, but with disproportional effects in low- and middle-income countries, whose health systems may be underdeveloped or lacking resources. It is important to remember that we are all at risk of epidemics produced by antimicrobial resistance.
What can be done to prevent antimicrobial resistance and the spread of resistance in antibiotic-resistant gonorrhoea?
To prevent the continued problem of multidrug-resistant N. gonorrhoeae infections two goals must be met.
We must control, on a broad level, drug resistance
We must control gonorrhoea (gonococcal infections)
Controlling gonococcal infections involves a range of actions:
Effective prevention and control of gonococcal infections, using prevention messages and interventions and appropriate treatment regimens
Effective drug regulations in place
Strengthened antimicrobial resistance surveillance; especially in countries with a high burden of gonococcal infections
Capacity building to establish regional networks of laboratories to perform gonococcal culture, with good quality control mechanisms
Systematic monitoring of treatment failures by developing a standard case definition of treatment failure and protocols for monitoring
Research into newer molecular methods for monitoring and detecting antimicrobial resistance
Identification of, and research into, alternative effective treatment regimens for gonococcal infections
What new medications are available/ what new research needs to be done to stop resistant gonorrhoea from becoming a worse issue?
Increasing resistance to the last-line treatment for gonorrhoea poses a big challenge because it limits the treatment choices available for gonorrhoea infections. The development of resistance clearly outpaces the development of new antibiotics. There is an urgent need to develop new treatment options for gonorrhoea.
The Global Antibiotic Research and Development Partnership (GARDP), a joint initiative between the World Health Organisation (WHO) and Drugs for Neglected Diseases initiative (DNDi), aims to facilitate the development, clinical evaluation and registration of new antimicrobials and therapeutic regimens for gonorrhoea. This is being accompanied by a sound access strategy and stewardship framework so that the newly developed antibiotics are not lost to resistance within a few years after their introduction.
Gonococcal antimicrobial resistance will only be effectively mitigated when additionally the global gonorrhea burden is reduced. This is why sex education is so important.
Apart from prevention through safer sexual behaviour, the development of a vaccine to prevent transmission is vital and an effective gonococcal vaccine is likely the only sustainable solution for the effective control of gonorrhoea.
Source: World Health Organisation
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