Skip to main content
STI & HIV 2023 World Congress Main banner
Final Program


Icon Legend
Back

Epidemiology & Monitoring

Category: STI - general

(P354) Infections with extensively antibiotic resistant Shigella sonnei and identification based on whole genome sequencing in Germany

Wednesday, July 26, 2023
16:00 – 18:00 CST


Background: Infections with Shigella sonnei can be fulminant and highly infectious, but most infections cause mild diarrhea. S. sonnei can be transmitted fecal-orally and sexually. Non-travel associated infections are mainly reported in men, with probable sexual transmission in men who have sex with men (MSM). Due to an increase in multi-drug-resistant (MDR) or extensively drug-resistant (XDR) infections, therapeutic options for more severe infections become limited.

After the United Kingdom (UK) reported on an unusual number of XDR- S. sonnei cases in February 2022, we analyzed isolates combined with notification data to determine a possible occurrence of such cases in Germany.



Methods: S. sonnei isolates sent to the National Reference Laboratory in 2021/2022 were investigated using whole genome sequencing and an Enterobase Escherichia/Shigella cgMLST v1-scheme adapted to characterize Shigella strains.



Results: We analyzed 59 isolates (2021: 14; 2022: 45). On basis of their cgMLST type and resistance associated gene profile we could assign 11/59 (2021: 4/14; 2022: 7/45) isolates to the same genetic cluster as the reference strain from the UK. Ten of these isolates were collected from men (one with no data), data on sexual orientation of the patients was not available. 3/4 cases in 2021 and all seven in 2022 were positive for CTX-M-27 plasmid.



Conclusion: Cases of S. sonnei showing MDR-/XDR-resistance have been present for more than four years in Europe. The currently reported type of S. sonnei containing the plasmid CTX-M-27 was identified in a multinational outbreak for the first time. Immunocompromised patients can experience a severe clinical course of infection and outbreaks in MSM are sometimes prolonged. Therefore, physicians treating MSM presenting with gastrointestinal symptoms should be sensitized for S. sonnei and consider this pathogen as differential diagnosis. In case of such an infection appropriate prevention measures should be recommended to stop further transmission. MSM reporting sexual risk behavior should be sensitized with regard to a possible fecal-oral transmission of Shigella and encouraged to report a possible sexual transmission to their physicians in case of gastro-intestinal discomfort with sudden onset. Because resistance to antibiotics is becoming more important, antibiotic treatment should be based on susceptibility testing.