As measures in place to curtail the spread of Covid-19 lifted throughout the country, the prevalence of superbugs in the Irish hospital system rose again. Some are at higher levels than pre-pandemic.
The “overshoot” is not surprising, according to Hilary Humphreys, emeritus professor of clinical microbiology at the Royal College of Surgeons in Ireland (RCSI), due to renewed pressure on the health system.
An analysis of official figures by The Irish Times shows there were 338 cases of hospital-acquired bloodstream Staphylococcus aureus infections in 2019. This dropped to 287 in 2020 when the Covid-19 pandemic arrived in Ireland. However, it rose again last year, reaching 352.
Not all those infections are the superbug MRSA, with most being MSSA, which is more easily treated. However, its presence is still a concern as even without the antibiotic-resistant component, there is an associated mortality.
The presence of Carbapenemase-producing Enterobacterales (CPE) is also now higher than it was three years ago. In 2019 there were 661 patients detected as having the resistant organism. It dropped to 656 in 2020, but rose to 682 in 2021.
Prof Humphreys said this rise between 2020 and last year was due to several compounding situations within the hospital system.
“There are more and more people presenting to hospital; because of delays [during the pandemic] they weren’t able to attend previously. We’re back up now to normal,” he said.
“There’s a lot of pressure on the system now as we speak, and staff shortages and the likes. Bed shortages obviously have all sorts of knock-on effects, including patients presenting later, with more complex, more at risk of infection than if they were presenting earlier in their illness. Bed shortages also means we put up additional beds in places where there isn’t enough space.”
The most concerning superbug for the health service is CPE.
Between 10 and 20 years ago, MRSA would have been the biggest concern. However, the prevalence of the bug last year reached its lowest level to date, according to the Health Protection Surveillance Centre (HPSC), representing just over 10 per cent of cases of S Aureus bloodstream infections.
While the threat MRSA poses hasn’t gone away, CPE has overtaken it in terms of numbers, according to Dr Eimear Brannigan, the HSE’s clinical lead for antimicrobial resistance and infection control.
It is generally regarded as the most dangerous superbug because it is resistant to almost all antibiotics. A national public health emergency team was established to tackle CPE in 2017.
It was unofficially stood down a number of years ago, having had its last meeting in 2019, just before the threat of Covid-19 took priority. However, now that the impact of the Sars virus has largely subsided, CPE is rising its head once more.
The HPSC said the five-year trend for CPE is increasing in Ireland, with 113 cases being reported in October 2022 alone, the highest level of detections in one month since surveillance started in 2019.
It found there were 11 outbreaks in hospitals across the State in September: in Tallaght University Hospital; MRH Mullingar; St Luke’s Hospital, Kilkenny; St Vincent’s University Hospital; Beaumont Hospital; Galway University Hospital; Sligo University Hospital; Cork University Hospital; Mercy University Hospital, Cork; University Hospital Waterford; and University Hospital Limerick.
An unpublished 2019 HSE document, obtained by The Irish Times under Freedom of Information laws, found there were “persistent environmental reservoirs” of superbug CPE in several hospitals, which was likely a “significant contributor” to the number of patients who contracted the bug.
The reservoirs are the likes of sinks, drains and other structural bodies of water that can become infected with the organism, though the HSE has carried out some capital works to reduce the number.
Not all superbugs are rising, however. VRE in Ireland has a higher prevalence rate than other European countries, but this difference has been narrowing over time.
Dr Susie Frost, consultant microbiologist at the HPSC, said it was not fully understood why Ireland typically had a higher prevalence level, though there were assumptions it could be related to agriculture.
The HPSC measures only VRE bloodstream infection, but the number of Irish patients colonised with the organism, which means those who carry the bacteria but are not unwell, is considerably higher.
For example, according to figures obtained by The Irish Times under Freedom of Information laws, Cork University Hospital had 699 VRE detections in 2019. The HPSC figures for the hospital that year was 12.
C Diff also remains lower than it was pre-pandemic, with 717 hospital-acquired cases last year, compared with 1,005 in 2019.
The spread of superbugs, as they are often known, is concerning, as they can delay recovery, or result in death.
And while there is an impact on the individual patient, there is also an impact on the health service.
A 2010 American paper, published in the international journal of pharmaceutical and healthcare marketing, said one day in hospital increased the risk of acquiring a healthcare associated infection (HAI) by 1.37 per cent, with each HAI resulting in an additional 9.3 days to length of stay.
According to a report by the Health Information and Quality Authority (Hiqa), antimicrobial resistance to eight bacteria of public health concern cost the health service an additional €12 million in extra hospital bed days in 2019.
Hiqa also found that these resistant infections resulted in about 215 deaths and almost 5,000 years of full health lost.
Dr Máirín Ryan, Hiqa’s deputy chief executive and director of health technology assessment, said: “To put this in context, this is similar to the burden reported in Ireland for certain cancers and rheumatoid arthritis.”
Dr Brannigan added that, while these numbers were “significant”, they were “likely to be an underestimate”, a position endorsed by Hiqa.
A recent study published in the Lancet backed this belief, finding that drug-resistant superbugs were responsible for more than 370 deaths of Irish patients in 2019.
Last month, Andrea Ammon, director of the European Centre for Disease Prevention and Control (ECDC), said it was seeing “concerning increases in the number of deaths attributable to infections with antimicrobial-resistant bacteria, especially those that are resistant to last-line antimicrobial treatment”.
But preventing the spread of these bugs is not easy. In 2019, then director general of the HSE Paul Reid said antibiotic-resistant superbugs posed an “existential threat” to the health service, that could become an irreversible problem.
Overcrowding and staff shortages are two of the biggest reasons why their presence continues in our health service.
Dr Brannigan said: “If they [patients] can reach out and touch the next bed or the next trolley, then that’s clearly a risk to other people. You can see why crowding is not a good thing.”
Prof Humphreys agreed, stating that when there were insufficient numbers of staff, they were under more pressure, which meant “they may not comply with hand hygiene in the way that they normally would”.
It is clear, then, that the threat of superbugs to the Irish healthcare system won’t truly abate until sufficient beds and staff are in place.
The bugs
Clostridium Difficile: Often referred to as C Diff, the organism thrives when the normal, healthy gut bacteria is disrupted. For someone who is ill with C Diff, it often means a course of diarrhoea that usually lasts only a few days, before settling. However, it can be severe, particularly in frail, older people, who tend to get distended bellies and sometimes need surgery to remove part of their colon.
MRSA: Many people have a common type of bacteria known as Staphylococcus aureus (SA) in their noses, which can cause minor skin infections. Methicillin is one group of antibiotics used to treat SA infections and the term MRSA refers to a type of SA that does not respond to treatment with antibiotics such as methicillin. If MRSA, or even MSSA, which can be treated with methicillin, gets into the bloodstream, it can be deadly in vulnerable patients.
CPE: Carbapenemase-producing Enterobacterales, referred to more commonly as CPE, are bacteria that live in the gut. A type of superbug, they are resistant to many antibiotics, meaning there are often limited treatment options for those who become ill with it. It is currently the most concerning superbug for the HSE as it is resistant to almost all antibiotics.
Vancomycin-resistant enterococci (VRE): Enterococci are bacteria found in the faeces of most humans and many animals. The most common are urinary-tract and wound infections. It is common in patients who have been in hospital for long periods, those on certain antibiotics and those fed by nasogastric tube.
ESBL: Extended-Spectrum Betalactamese, or ESBLs, are common antibiotic-resistant bacteria, which can cause a serious infection if they get into the blood, kidneys, bladder or body tissues. There are three things that put one at increased risk of being infected with an ESBL: major surgery, having a medical device inserted into your body, such as a catheter or IV line, and cancer treatment.
SRSV: The small round structured virus, often referred to as the winter vomiting bug, is a particularly resistant microbe spread through the air and by personal contact. Symptoms include severe, often projectile vomiting, diarrhoea, abdominal pain and mild fever. However, most vanish in 48-72 hours, with many able to recover without hospital care.