E. coli in Canada: Infection Facts and Vaccine Research

E. coli is a bacterium that lives normally in the gut, where most strains cause no trouble. A few do: some bring severe diarrhoea, others cause urinary and bloodstream infections, mostly in older adults. This page covers the infection and where vaccine research stands.

By the numbers in Canada

812laboratory-confirmed Shiga toxin-producing E. coli isolates were reported to Canada's National Enteric Surveillance Program in 2022: 299 E. coli O157 (0.77 per 100,000 people) and 513 non-O157 (1.32 per 100,000). It was the sixth year in a row that non-O157 outnumbered O157.

Source: Public Health Agency of Canada, National Enteric Surveillance Program annual summary, 2022

A prospective study of 240 hospitalised older adults across eight sites in seven countries including Canada found the urinary tract was the most common source of invasive E. coli disease (62.9%), with in-hospital mortality of 4.6%. Of the isolates tested, 30.4% were resistant to trimethoprim-sulfamethoxazole, 24.1% to ciprofloxacin and 16.4% to ceftriaxone. Source: Infection (journal), 2024
PHAC's Canadian Antimicrobial Resistance Surveillance System reports that infections caused by extended-spectrum beta-lactamase (ESBL) producing Enterobacterales, the bacterial family that includes E. coli, are trending upward and remain a high-priority pathogen group in Canada. Source: Public Health Agency of Canada, CARSS 2025 key findings, 2025
The same report cites projections that by 2050 as many as 13,700 people in Canada could die each year because of antimicrobial resistance, with an estimated $388 billion loss to gross domestic product and $120 billion in health care costs. Source: Public Health Agency of Canada, CARSS 2025 key findings, 2025

Worldwide4.7 million deaths globally were associated with bacterial antimicrobial resistance in 2021, and the World Health Organization names E. coli and Klebsiella pneumoniae as the leading drug-resistant Gram-negative bacteria found in bloodstream infections. These are international figures.Source: World Health Organization, antimicrobial resistance fact sheet, 2026

What E. coli is, and what it is not

Most people know E. coli from food recalls, and Shiga toxin-producing strains such as O157 do cause cramping and bloody diarrhoea, sometimes with kidney damage. That is only part of the picture. Other strains, called extraintestinal E. coli, come from a person’s own gut bacteria and cause most urinary, kidney and bloodstream infections.

This is also not a page about an available vaccine. No E. coli vaccine is authorised in Canada, or anywhere else, and nothing is close to being offered.

Signs and symptoms

Shiga toxin-producing E. coli: severe cramps, watery diarrhoea that often turns bloody, and vomiting
Haemolytic uraemic syndrome, mostly in young children and older adults: much less urine, paleness and bruising
Urinary tract infection: burning when you urinate, going often and urgently, cloudy urine, low abdominal pain
Bloodstream infection: fever or low temperature, shivering, rapid breathing, confusion; in an older adult confusion may be the only sign

The same bacterium causes a few uncomfortable days in one person and a hospital stay in another.

A young adult in a bright clinic room with a sleeve rolled up, one hand resting over the upper arm. — No E. coli vaccine is authorised in Canada. The largest late-stage trial of a candidate was stopped in 2025. Illustrative photograph.

What raises the risk

Some risk factors cannot be changed:

Being a young child or an older adult, the groups most likely to develop haemolytic uraemic syndrome
Female anatomy, which is why urinary tract infection is far more common in women
A urinary catheter, an enlarged prostate, kidney stones or a weakened immune system

Others can often be worked on, usually with support from a health care team:

Food and water handling: undercooked ground beef, unpasteurised milk, raw sprouts and untreated water are the usual sources
Hand washing after the toilet and after contact with farm animals
Repeat and unnecessary antibiotic courses, which add to resistance

How E. coli infection is diagnosed in Canada

Shiga toxin-producing E. coli is confirmed on a stool sample by culture and molecular testing, and isolates go to the National Microbiology Laboratory for sequencing, which is how scattered cases get linked into an outbreak. Urinary tract infection is assessed on symptoms, often with a urine dipstick, plus a urine culture when symptoms recur. In older adults clinicians look carefully before treating, since bacteria in the urine without symptoms is not an infection.

Treatment and day-to-day management

Care depends on which kind of infection you have. A health care team may discuss:

For Shiga toxin-producing E. coli: fluids, rest and monitoring of kidney function, with hospital care if haemolytic uraemic syndrome develops
For urinary tract infection: an antibiotic chosen using local resistance patterns and your other medicines
For invasive infection: hospital admission and intravenous antibiotics

What suits one person will not suit another. These are decisions for you and your own clinician.

When to talk to a doctor

Call 911 or go to an emergency department for fever with shivering, rapid breathing or confusion, or if an older adult with a suspected infection cannot be roused.
Seek care the same day for bloody diarrhoea, for passing much less urine, or for a child who becomes pale or bruises easily after diarrhoea.
Seek care the same day for fever with back or side pain and vomiting, a possible kidney infection.
Contact your health care provider for burning on urination that is not settling, or symptoms returning soon after antibiotics.

Why clinical research matters for E. coli infection

The largest late-stage attempt was E.mbrace, a phase 3 trial of a nine-valent candidate in adults 60 and older with a recent urinary tract infection. In February 2025 the sponsors announced that an independent monitoring committee found it was not sufficiently effective at preventing invasive E. coli disease compared with placebo, and the study stopped, with no vaccine-related safety signals. The problem remains: the World Health Organization names E. coli among the leading drug-resistant causes of bloodstream infection, and PHAC reports ESBL-producing infections increasing here. Research continues on other vaccine designs and faster resistance testing.

Taking part is voluntary. You give informed consent first, and you can stop at any time without affecting the care you get from your own doctor. No one can say in advance whether a study will help you personally.

Learn more from Canadian sources

Where this information comes from (6 sources)

This page is written in plain language for people considering clinical research. It is general health information, not medical advice, and it does not replace a conversation with your own doctor or nurse practitioner.

Common questions

Is there an E. coli vaccine I can get in Canada?

No. There is no E. coli vaccine authorised in Canada, and none authorised anywhere else. The largest late-stage attempt, the phase 3 E.mbrace study of a nine-valent candidate in adults 60 and older with a recent urinary tract infection, was stopped in February 2025 after an independent data monitoring committee found it was not sufficiently effective compared with placebo. Research on other approaches continues, but nothing is close to being available.

Why is E. coli connected to antibiotic resistance?

Because it is so common. E. coli causes most urinary tract infections, and urinary tract infections are one of the most frequent reasons antibiotics are prescribed. The World Health Organization names E. coli and Klebsiella pneumoniae as the leading drug-resistant Gram-negative bacteria in bloodstream infections. In the multinational study of invasive E. coli disease that included Canadian sites, 30.4% of isolates were resistant to trimethoprim-sulfamethoxazole and 24.1% to ciprofloxacin, both common oral antibiotics. Canada's surveillance system reports that ESBL-producing infections are trending upward here.

Are the E. coli that causes bloody diarrhoea and the E. coli that causes urinary infections the same thing?

They are different groups of strains of the same species. Shiga toxin-producing strains, including O157, make a toxin that damages the gut lining and can damage the kidneys, and are usually picked up from food or water. The strains that cause urinary tract infection, bloodstream infection and sepsis are called extraintestinal E. coli, and they usually come from a person's own gut bacteria rather than from contaminated food. They are investigated, treated and prevented in quite different ways.

What to do next

Talk to your doctor. This guide is information, not medical advice.
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E. coli Vaccine Research