No cause for complacency on VTEC

In late 2019, the Medical Independent reported on a briefing note sent by the Chief Veterinary Officer (CVO) to the Chief Medical Officer (CMO) concerning the “unacceptable” rate of human verotoxin-producing E.coli (VTEC) infection in Ireland. The briefing note, sent by the CVO Dr Martin Blake to the then CMO Dr Tony Holohan, stated that a “large” outbreak in the future was “a real threat”.

The communication, dated July 2019, advocated for a ‘one health’ and inter-departmental approach to reducing the level of infection.

Of course, within months, an outbreak of a different nature had consumed the Department of Health, the country, and the world.

The Covid-19 pandemic delayed plans to develop a national action plan on VTEC, and the “national approach” remains the subject of “ongoing discussions”. A spokesperson for the Department of Agriculture, Food and the Marine (DAFM) said these talks involve the Environmental Protection Agency; HSE; Food Safety Authority of Ireland; and other relevant partners.

According to the DAFM, the discussions are taking account of changes in the system under the public health reform programme and publication of the HSE’s National Health Protection Strategy 2022-2027.

For many years, Ireland has had one of the highest VTEC notification rates in Europe, far exceeding the average.

This country’s high number of cattle per capita, the sizable population accessing private well water, and sensitive surveillance and laboratory systems, are factors contributing to the notification rate.  

According to 2022 data, key risk factors for VTEC infection included exposure to private well water, animal/environmental exposures, and attendance at a childcare facility (ie, person to person spread). A smaller percentage of cases were foodborne (where the exposure routes were known).

In 2018, the crude incidence rate (CIR) of VTEC was at its highest to date (23.4/100,000) but decreased to 18.3/100,000 in 2019. In 2022, it was 19/100,000, representing a 3 per cent increase on 2021, according to data from the Health Protection Surveillance Centre (HPSC).

Some 78 outbreaks were notified in 2022, an increase from 62 in 2021 but slightly below the typical numbers reported pre-pandemic.

The threat posed by this infection, particularly to children and older people, is significant. Of the 980 cases notified in 2022, some 322 people (33 per cent) were hospitalised. There were 24 cases of haemolytic uraemic syndrome, a potentially life-threatening condition.

Four deaths occurred among people with VTEC; two deaths were not caused by the infection, and the cause of death was not known for the other two cases, according a HPSC report.

An inter-agency plan is required with clear actions and a lead implementation body for each.

Increasing rainfall due to climate change is adding to this country’s risk profile and an action plan should be progressed without delay.