Preliminary microbiological testing results suggest that some E. coli outbreaks in Latvia may be linked to specific food products, possibly even a combined outbreak where a single product is contaminated with multiple pathogens, the Centre for Disease Prevention and Control (SPKC) informed news agency LETA.
SPKC specialists continue their epidemiological investigation and have drawn these initial conclusions based on the first laboratory test results.
The strains of E. coli capable of producing toxins are referred to as STEC/VTEC (Shiga toxin- or verotoxin-producing E. coli). According to SPKC, laboratory tests have confirmed two STEC serotypes — 0103 and 026 — found in infected individuals. This indicates the presence of multiple modes of transmission. As a result, current findings suggest either separate outbreaks or a combined outbreak caused by one contaminated product hosting different pathogens. Food and surface swab samples are being analysed by the Food and Veterinary Service (PVD).
By the 3rd of April, 58 cases had been registered, including seven adults. There are 27 cases in Riga, ten in Sigulda municipality, eight in Adazi municipality, three each in Cēsis and Liepāja municipalities, two each in Salaspils and Ķekava municipalities, and one each in Jelgava, Ropaži and Dienvidkurzeme municipalities.
Cases have been identified in 28 educational institutions — 26 preschools and two primary schools.
Currently, 153 contacts have been tested, and approximately 900 people have been identified as contact persons within educational institutions and households.
Currently, epidemiologists are working on several fronts and several large-scale activities are underway to guide the investigation of cases, according to the SPKC.
These include providing guidance to all affected educational institutions, contacting the general practitioners of all infected individuals, interviewing all patients and legal guardians to gather and analyse information. As well as communicating with parents and staff currently absent from school, especially those absent due to illness, visiting affected schools and organizing lab testing for all kitchen staff (results pending), collecting and reviewing meal plans from the institutions.
SPKC has also been in contact with experts from the European Centre for Disease Prevention and Control (ECDC) regarding the epidemiological measures being implemented. In cooperation with them, updated protocols for doctors will be developed to guide diagnosis and the timely detection of Haemolytic Uremic Syndrome (HUS) — a serious complication of the infection.
According to the Children’s Clinical University Hospital (BKUS), a total of 28 children have been hospitalized since the start of the outbreak with confirmed STEC infections. As of the 3rd of April, 12 children have been discharged and are continuing treatment at home.
Currently, 16 children remain hospitalized, including 12 in the Infectious Diseases unit and four in the Intensive Care unit.
Earlier this week, the PVD received lab results from 55 food samples taken from preschools where cases had been identified. No contamination with STEC was detected in these samples.
SPKC explains that Escherichia coli (E. coli) is a type of bacteria naturally found in the intestines of humans and animals. Most strains are harmless, but some can produce toxins and cause severe illness.
These pathogenic strains are known as STEC/VTEC. They can cause severe, bloody diarrhoea and, in some cases, lead to acute kidney failure, requiring intensive care.
The primary reservoir for these strains is herbivorous animals, especially cattle. The bacteria are excreted via faeces and can spread to humans through contaminated food (e.g., undercooked beef, unpasteurized milk), unwashed fruits or vegetables, direct person-to-person transmission.
SPKC reminds the public to properly cook all food, thoroughly wash fruits and vegetables, especially those that will not be cooked, seek medical attention immediately in case of symptoms such as abdominal cramps or bloody diarrhoea
In Latvia, this type of infection was registered 42 times in 2023, with an average of 4–5 cases per month, according to SPKC.