a. Pre-existing respiratory conditions such as asthma, COPD, bronchiectasis, cystic fibrosis, taking daily inhaled steroid.

b. Individuals who had organ transplant.

c. Type 1 and Type 2 Diabetes Mellitus.

d. Heart Problems (Heart Failure, Angina, History of Heart Attack).

e. Chronic Kidney Disease (stage 3 and above).

f. Chronic Liver Disease including Hepatitis.

g. People with cancer who are undergoing active chemotherapy, people with lung cancer who are undergoing radical radiotherapy, people with cancers of the blood or bone marrow such as leukaemia, lymphoma or myeloma who are at any stage of treatment, people having immunotherapy or other continuing antibody treatments for cancer, people having other targeted cancer treatments which can affect the immune system, such as protein kinase inhibitors or PARP inhibitors, patients receiving radiotherapy or immunotherapy.

h.  People who have had bone marrow or stem cell transplants in the last 6 months, or who are still taking immunosuppression drugs.

i. People with rare diseases that significantly increase the risk of infections (such as SCID, homozygous sickle cell).

 j. Autoimmune disorders including on-going inflammatory bowel conditions (Crohn’s, Ulcerative Colitis).

k. Pregnant women.

l. Older individuals with comorbid conditions.

m. Reduced Immune Response - AIDS/HIV, regular oral steroids.

n. Obesity.

o. Chronic alcohol abuse, heavy smoking.

p. Chronic Neurological Conditions (Parkinson’s, Motor Neurone Disease, history of stroke (CVA), Multiple Sclerosis, Cerebral palsy).

q. Hypertension (on one or more anti-hypertensive medications.

r. Migrant population from tropical countries.