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Covid-19 HSE Clinical Guidance and Evidence

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HSE Frameworks and Operational Pathways of Care

HSE consensus advice regarding patients at risk of significant ill-health due to COVID-19

HSE consensus advice regarding patients at risk of significant ill-health due to COVID-19 (CD19-004-001 / 08.03.21)

  • Target audience: Health care professionals.
  • This document summarises and signposts to current guidance relating to groups who are at increased risk of significant ill-health from COVID-19 due to underlying health conditions.
  • There are also social circumstances which may increase the risk of certain populations and which can be compounded by the common coexistence of clinically vulnerabilities in these groups.  Advice in relation to socially vulnerable groups and specific settings is available from the HPSC here:
  • This is a summary of current guidance in this area.  It is not intended to replace a clinician’s assessment of an individual patient’s risk or tailored advice. 
Risk categorisation

Very high risk

The use of the term ‘extremely medically vulnerable’ has been replaced with ‘very high risk’, to avoid confusion with social vulnerability. 

Those clinical conditions included here are those which have been assessed by the National Immunisation Advisory Committee (NIAC*) as having a very high risk of severe COVID-19 disease, which is similar to that of those aged over 70 years of age.  The list is not intended to be exhaustive and is subject to clinical judgement, particularly in the context of multiple comorbidities.

  • Age >70: The most consistent evidence remains that in relation to risk with increasing age, particularly with each decade from 60 upwards.  The co-existence of clinical co-morbidities with increasing age is of course an important factor.
  • Cancer:
  • Those cancer patients actively receiving (and/or within 6 weeks of receiving) systemic therapy with cytotoxic chemotherapy, targeted therapy, monoclonal antibodies or immunotherapies; undergoing complex cancer surgery, e.g. for lung, oesophageal or head and neck cancer; or radical radiotherapy for lung cancer or head and neck cancer. 
  • Those who are listed for a haemopoietic stem cell transplant (HSCT) or received a HSCT within the past 12 months.
  • All patients with advanced/metastatic cancer.
  • Chronic neurological conditions which cause significant respiratory compromise: Those with evolving ventilatory failure requiring non-invasive ventilation, e.g. due to Motor Neuron Disease or Spinal Muscular Atrophy
  • Chronic severe respiratory disease including: Those with Cystic Fibrosis whose disease is unstable or severe, including people awaiting transplantation; those with severe pulmonary fibrosis, or severe chronic obstructive pulmonary disease (COPD)
  • Down Syndrome
  • End stage kidney disease: This includes those on renal replacement therapy, whether haemodialysis or peritoneal dialysis, and those with a GFR of less than 15 mls/min per 1.73 m²
  • Inherited Metabolic Diseases: Those who are considered at risk of acute decompensation, e.g. Maple Syrup Urine Disease
  • Obesity with a BMI >40 kg/m2
  • Rare immunodeficiency conditions: such as APECED (autoimmune polyendocrinopathy candidiasis ectodermal dystrophy) or interferon pathway defects
  • Solid organ transplantation: Those who have ever received a solid organ transplant or who are listed for a solid organ transplant
  • Significant immunocompromise due to treatment: such as those treated within the past six months with immunomodulatory drugs including but not limited to Cyclophosphamide, Rituximab, Alemtuzumab, Cladribine or Ocrelizmab
  • Sickle Cell Disease
  • Uncontrolled diabetes: e.g. Those with a HbA1C of >58mmol/mol

Other high risk groups

There are additional groups who can be considered at high risk of severe COVID-19 disease, again in accordance with current NIAC* advice.


  • Chronic kidney disease: with a eGFR <30ml/min and not otherwise in the very high risk category
  • Chronic respiratory disease:  those with significant respiratory disease not included in the very high risk category such as stable cystic fibrosis; moderately severe chronic obstructive pulmonary disease (COPD); severe asthma (continuous or repeated use of systemic corticosteroids)
  • Diabetes Type I or II: unless in the very high risk category due to poor control
  • Immunocompromise due to disease or treatment:  and not otherwise in the very high risk, such as those on high dose systemic steroids and those living with HIV
  • Inherited Metabolic Disorders: Other than those in the very high risk category who are at risk of acute decompensation
  • Intellectual disability: excluding Down Syndrome which is in the very high risk category
  • Chronic neurological disease or condition: including those with significantly compromised respiratory function and/or ability to clear secretions and who are not otherwise in the very high risk category e.g. Parkinson’s disease, cerebral palsy
  • Obesity with a BMI >35 Kg/m2
  • Patients undergoing cancer treatment: and who are not otherwise in the very high risk category, including those who were treated for a solid tumour within the past year; those with a haematological malignancy within the past 1-5 years; for those with any other cancer who are on active treatment non-hormonal treatment
  • Chronic heart (and vascular) disease: including heart failure, hypertensive cardiac disease
  • Chronic liver disease: including cirrhosis or fibrosis
  • Severe chronic mental illness: including schizophrenia, bipolar disorder, severe depression


Risk minimisation

Population measures

  • Population measures to limit and/or delay spread of the virus are key for the protection of at risk groups. These include hand hygiene and cough etiquette; environmental measures; restricted movements of close contacts; voluntary isolation of symptomatic cases not requiring hospitalisation; social distancing; and use of face coverings.
  • Close adherence to these measures by at risk individuals and their immediate contacts has two benefits: (i) to reduce the likelihood of the at-risk person being infected with COVID-19 and (ii) to contribute to the population effort to reduce the number of people who become ill and to spread the number of people who become ill over a longer period of time, ensuring greater ability of the health care system to provide optimal care to the at-risk individual, should they acquire COVID-19.

Additional precautions for those at-risk

  • Additional strategies can be employed by those at-risk, to further reduce their likelihood of coming into contact with someone with COVID-19. While the aim is to significantly reduce their contact from outside the home (e.g. by others getting their groceries, filling prescriptions), it is important that they do not disengage from the supports that are required to keep them well. It is important to emphasise that those at increased risk for COVID-19 retain autonomy and that they exercise choice over the additional measures employed to reduce their risk.
  • Detailed advice is available in HPSC COVID-19 Guidance for Older People and Others at Risk of Severe Disease on Reducing Risk of COVID-19 Infection
  • This includes general occupational advice for at-risk groups. Specific guidance for healthcare workers in higher risk categories* is available here:
  • Advice in relation to attendance in school settings is available here Children who are household members of those in at-risk groups can continue to attend school.  Most children who are themselves in at-risk groups can continue to attend, with an individual risk assessment required for those with profound immunocompromise or highly complex medical needs. Staff members who are in the very high risk category are generally advised to continue working remotely.


  • Details of the order of prioritisation for those in at-risk groups for severe COVID-19 disease are outlined in the COVID-19 Vaccine Allocation Strategy in Ireland’s COVID-19 vaccine plan The strategy was developed by the National Immunisation Advisory Committee (NIAC) and Department of Health, endorsed by the National Public Health Emergency Team (NPHET), and approved by Government. It will remain subject to revision.
  • Currently those aged 16-69 with a medical condition that puts them at very high risk of severe disease and death are in priority group 4 and to be vaccinated following those aged 70 and older. Those aged 65-69 and considered high risk are in group 5, to be immunised before others in their age group (group 6). Those aged 16-64 and at high risk are in priority group 7.
  • mRNA vaccines may be used preferentially in those who are less likely to mount an optimum response.  However, this should be balanced against any resultant delay in administration. Further detail in relation to COVID-19 vaccines is available in the Immunisation Guidelines for Ireland Chapter 5a.

Accessing ongoing health care

  • The at-risk groups described here are also those who are most likely to be in need of ongoing health and social care, be it in the community or hospital setting. Proactive measures are required to ensure safe delivery of essential care, while minimising their risk of exposure to COVID-19. This includes strict adherence to infection prevention and control advice and minimisation of contacts where this will not compromise care, e.g. by task sharing or virtual assessment.
  • Patients should be advised to attend for scheduled care unless otherwise advised but to contact the service in advance if they have developed any symptoms of possible COVID-19 or have been in close contact with someone with the disease. Where feasible services should contact patients in advance of attendance, both to confirm they are well and that treatment is proceeding. 
  • Measures outlined for the safe delivery of scheduled services in acute hospitals are of particular relevance to at-risk groups attending for essential care at this time.
    Guidance on the management of scheduled services for adults in acute hospitals during the COVID-19 era

Minimising Impact on Wellbeing




  • Version 1 Authored by Triona McCarthy, Public Health; Martin Cormican, Infection Prevention and Control; Margaret Fitzgerald, Public Health
  • Version 2 Revision authored by Triona McCarthy, Public Health; Barbara McGrogan, Research Scientist

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