Clinician alert: multi-drug resistant Shigella sonnei

Key points:

1. Queensland has seen a recent increase in a multi-drug resistant strain of Shigella sonnei infection among cases of gastroenteritis, particularly affecting men who have sex with men. 
2. The strain is typically resistant to ampicillin/amoxicillin, third generation cephalosporins (including ceftriaxone), cotrimoxazole, macrolides (azithromycin) and quinolones (ciprofloxacin/norfloxacin).
3. Clinicians should be alert to at risk patients who present with acute gastrointestinal symptoms and arrange appropriate testing including culture and sensitivities. 
4. Please seek further advice from an infectious disease physician if required.

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.

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.

Management

• 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

• Good hand hygiene practices 
  • thorough hand washing particularly after using the toilet, and before and after food handling
  • do not prepare food or drink for others or share utensils
  • patients who work in high-risk jobs (e.g. childcare, food preparation, healthcare) should not return to work until 48 hours after diarrhoea has ceased and a negative faecal culture or PCR  (see Shigella infection | Queensland Health Guidelines for Public Health Unit).
• Appropriate safer sex messaging should include: 
  • abstinence from all sexual practices while symptomatic and for one week after diarrhoea 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 you switch from anal to vaginal or oral play.

Management of contacts

• Contacts of people with confirmed multi-drug resistant strains should be contacted to advise them of their exposure, provide education about shigellosis, and to seek medical advice if symptomatic. 
• Reinforce preventive actions described above to help prevent further transmission.

Further information

Queensland Public Health Units

Shigella infection | Queensland Health Fact Sheet