In September, the Brussels region recorded a notable rise in declarations of STEC (Shiga toxin-producing Escherichia coli). However, this increase needs nuance: no hospitalizations or cases of hemolytic uremic syndrome (HUS) were reported. Health authorities attribute this trend to improved sensitivity of PCR detection tests.
The post-holiday return period also saw a resurgence of common infections, often contracted in destination countries. These include Hepatitis A, Shigellosis, Legionellosis, and Typhoid Fever.
Also noteworthy is the emergence of the West Nile Virus, with the first two cases reported in the capital. The activity period of the mosquito vector for the disease is expected to end in late October. Vigilance is therefore advised, particularly for the elderly and/or fragile individuals: use mosquito nets, close windows at night, apply repellent, and wear long clothing when going out after sunset.
Shigellosis ranked second in terms of declarations in September, with 11 cases notified (4 confirmed, 7 probable). This highly contagious acute intestinal infection occurs after an incubation period of 1 to 7 days, with symptoms including fever, abdominal pain, and diarrhea, sometimes bloody. While classically associated with travel, nearly half of documented European cases are linked to stays abroad. In Brussels, at least 7 cases in September 2026 were related to returning from holidays.
Shigella has also increasingly become recognized as a sexually transmitted infection, particularly among men who have sex with men. The ECDC warned in May 2026 about the spread of multi-drug resistant, even extensively drug-resistant, strains in Europe. Therefore, considering shigellosis in cases of acute diarrhea in MSM patients and screening for other STIs is essential.
In the laboratory, multiplex PCR panels have changed the game: more sensitive than stool culture, they detect more infections. However, stool culture remains indispensable for confirming the diagnosis and performing antibiotic susceptibility testing.
In the majority of cases, rehydration and patience are sufficient, with a generally favorable outcome within a week. Antibiotics are reserved for severe forms or situations with transmission risk. And lacking a vaccine, prevention relies on two pillars: good hygiene and abstaining from sexual intercourse until two weeks after symptom resolution.
