Clinical alert: Multiple drug-resistant shigella sonnei
An increase in a multiple drug-resistant (MDR) strain of shigella sonnei infection among cases of gastroenteritis have recently been reported, affecting men who have sex with men (MSM) in particular.
Queensland Health advises clinicians to be alert to at-risk patients who present with acute gastrointestinal symptoms and arrange appropriate testing including culture and sensitivities.
About shigella sonnei
Shigellosis is a notifiable bacterial disease characterised by an acute onset of diarrhoea, fever, nausea, vomiting and abdominal cramps.
Antimicrobial resistance in shigella isolates is increasing with the percentage of MDR shigella sonnei infections steadily increasing in recent years.
This strain is typically resistant to:
ampicillin/amoxicillin
third generation cephalosporins (including ceftriaxone
cotrimoxazole
macrolides (azithromycin)
quinolones (ciprofloxacin/norfloxacin).
The most common mode of transmission of shigella is via the faecal-oral route. This can occur during sexual activity, however infection may also be spread by contaminated food or water.
Shigellosis management
Queensland Health’s advice for shigellosis management is as follows:
If shigella is suspected, investigate as usual. Request stool culture and full sensitivities including azithromycin.
Refer to current edition of Therapeutic Guidelines.
Empirical antibiotics are not recommended due to the high rates of resistance. Where specific management is required, it should be guided by the culture and sensitivities.
For severe cases where empirical therapy is indicated, seek advice from an infectious diseases specialist.
Advice for patients
Clinicians are encouraged to remind patients about good hand hygiene and safer sex practices.
Good hand hygiene practices include:
thorough hand washing particularly after using the toilet, and before and after food handling
do not prepare food or drink for others or share eating utensils
patients who work in high-risk jobs (e.g. childcare, food preparation, healthcare) should not return to work until 48 hours after diarrhea has ceased and a negative faecal culture or polymerase chain reaction (PCR) —see Shigella infection Queensland Health Guidelines.
Appropriate safer sex messaging includes:
abstinence from all sexual practices while symptomatic and for 1 week after diarrhea has stopped
washing hands, genitals, anus and sex toys before and after sexual activity
using barrier methods such as condoms, dental dams or finger cots during anal and oral sex, making sure to use a new barrier each time there is a switch from anal to vaginal or oral activity.
Management of contacts
Contacts of people with confirmed MDR strains should be contacted to advise them of their exposure, provide education about shigellosis, and to seek medical advice if symptomatic.