The team, comprising of researchers from University of Nairobi, Manitoba (Canada), Oxford Washingtonand Chicago, the Kenya Medical Research Institute (KEMRI), the National AIDS and STIs Control Programme (NASCOP), found the ‘prevalence of fluoroquionolone resistance in gonorrhoeae is high in several parts of Kenya’
The paper summarises their findings by noting that ‘We have recently reported high levels of fluoroquinolone resistance in a single region of Kenya. We report high prevalence of fluoroquinolone resistance (53.2%) in Neisseria gonorrhoeae isolates from four clinics in three additional regions of Kenya.’
The team collected and tested samples from various regions in Kenya targeting ‘high risk individuals.’
‘Isolates were collected in 2009 and 2010 from four sites: Kisumu in western Kenya, the capital city Nairobi located on the principal highway connecting Mombasa and Kisumu, and Mombasa and Kilifi in coastal Kenya. Isolates were collected from high-risk individuals attending community or research clinics for medical care which included screening and management of sexually transmitted infections.’
More than 150 individual’s samples were collected and sampled.
‘A total of 154 single isolates from 82 females and 72 males were tested: 64 from Kisumu, 44 from Nairobi, 29 from Mombasa and 17 from Kilifi.’
They noted that the the gonorrhoea strain was becoming resistant to widely used treatments.
‘Although fluoroquinolone therapy was considered first line therapy for treatment of gonorrhoea for a number of years, most national guidelines from industrialized countries now discourage their use because of high resistance rates.’
The team cautioned that there was urgent need to curtail the spread of the strain and called for emergency measures and treatment to be made available.
‘The potential emergence of multi-drug resistant N. gonorrhoeae underscores the urgency of ongoing surveillance for timely detection and response.’
The researchers could not explain why the new strain was resistant to treatment. They note that this may be due to mutation.
‘The cause of emergence of resistance is unclear. Possible explanations include progressive accumulation of Quinolone-Resistant Determining Region (QRDR) mutations leading to resistance, or the spread of a drug resistance clone introduced into Kenya leading to more rapid emergence such as that which has recently occurred in South Africa.’
Furthermore, they note ‘As with penicillin and tetracycline, it is likely that generalized overuse of fluoroquinolones has contributed to the emergence of resistance.’
The research, though limited to individuals, does not represent a random sample. The specimens were collected from individuals attending research clinics.
‘Considering the estimated 2–3% prevalence rate of gonorrhoea in sub-Saharan Africa our numbers constitute a very small proportion of the total number of cases in Kenya. In three sites, patients were nearly exclusively high risk sex workers.’
They also note that the participants had previously been involved in STI screening and treatment and that may have led to the resistance.
‘Participants in these cohorts may have been exposed to higher rates of STI screening and treatment than the general population, which may have influenced the proportion of isolates with fluoroquinolone resistance.’
They were concerned that the gonorrhoea was becoming resistant and this could easily spread to other persons.
‘The findings remain striking, and raise concern that widespread resistance to fluoroquinolones could already be present in Kenya. The high resistance rates observed in the symptomatic men without defined risk factors from Kisumu also suggests that high resistance rates may extend beyond high-risk cohorts.’
They called for a change in the first-line treatment of gonorrhoea especially for high risk populations and the general population.
‘The high level of resistance to fluoroquinolones in gonorrhoea isolates from a range of higher risk populations in different regions of Kenya is worrisome. These data suggest that recommended regimen for first-line treatment of gonorrhoea should be changed to cefixime or a recognized alternative cephalosporin in high-risk populations.’
‘Careful consideration should be given to changing the recommended regimen in other populations as well,’ they added.
The World Health Organisation (WHO) has issued an alert on this untreatable strain of gonorrhoea and said ‘the pathogen had developed resistance to many of the common antibiotics used in treatment, including penicillin, tetracyclines and quinolones.’