Vaccine Confidence: Co-morbidities and COVID-19

Tips for Health Workers to answer COVID-19 questions right

Nurse is vaccinating a patient amidst Coronavirus at AUA in Yerevan.
UNICEF / Lilian Galstyan
29 December 2021

Co-morbidities are conditions associated with worse health outcome.

In the case of COVID-19, these are underlying medical conditions associated with high risk of severe COVID-19 infection, hospitalizations, and even death.


People of any age with underlying health conditions are more likely to get severely ill, require hospitalization and die from COVID-19.

The risk of severe COVID-19 increases as the number of underlying medical conditions increases in a person.

That's why vaccination is strongly recommended for them.

COVID-19 vaccines have been found to be safe and effective for people with co-morbidities.

Therefore, the presence of one or more underlying health conditions in an individual should be an additional reason to opt for vaccination and not to put it off.


Not an exhaustive list.

More conditions may be added as evidence emerges.

HEART - Cardiovascular diseases, high blood pressure (hypertension), coronary heart disease, congestive heart failure and cardiomyopathies.

LUNGS - Asthma, chronic obstructive pulmonary disease, bronchiectasis, tuberculosis, bronchopulmonary dysplasia, cystic fibrosis, pulmonary embolism and respiratory infection other than pneumonia.

KIDNEY - Chronic kidney disease

LIVER - Chronic liver disease, such as alcohol-related liver disease and non-alcoholic fatty liver disease.

NEURO - Dementia, a severe problem with the brain or nerves, such as cerebral palsy, mental health conditions including schizophrenia spectrum disorders and other neurological conditions.

IMMUNOCOMPROMISED - Persons with weakened immune systems include people with HIV/AIDS, cancer, transplant patients who take immunosuppressive drugs and those with inherited diseases that affect the immune system such as congenital agammaglobulinemia, congenital IgA deficiency etc.,



Can people with co-morbidities or underlying health conditions receive the COVID-19 vaccine?


COVID-19 vaccination is recommended for people with co-morbidities or underlying health conditions since they are at a higher risk for severe COVID-19.

Population groups with chronic lung disease, significant cardiac disease, respiratory disease, severe obesity, diabetes, cancer, liver disease and human immunodeficiency virus (HIV) infection and AIDS were included in a few of the COVID-19 vaccines’ clinical trials.

The results demonstrated similar safety profiles and COVID-19 vaccines have been found to be safe and effective in people with pre-existing medical conditions that are associated with increased risk of severe disease.

Vaccines are also strongly recommended for pregnant and lactating women and also for people who have had COVID-19 in the past.{1]

What is considered an underlying medical condition/a co-morbidity for COVID-19 vaccination?

Individuals of any age with one or more underlying medical conditions are at increased risk for severe COVID-19.

Check the list of comorbidities under the topic 'Conditions associated with a greater risk of severe COVID-19'.

Please note this is not a complete list and only includes conditions with sufficient evidence to draw conclusions.

Individuals with those conditions should be prioritized for vaccination.

Should people with weakened immune systems or immunocompromised get vaccinated?

Weakened immune systems mean that the immune system in one’s body functions sub-optimally either due to a medical condition or due to medication they take. People with weakened immune systems or immunocompromised should get vaccinated against COVID-19.

Having a weak immune system puts them at higher risk of serious illness with COVID-19 and getting vaccinated offers some level of protection, which is better than no protection.

The potential benefits of vaccination far outweigh the possible risks and people with weakened immune systems should proceed with COVID-19 vaccination.

Consulting their doctors who treat patients' immunocompromising conditions is recommended to discuss and understand the risks and benefits of vaccination, including whether the vaccine might require special timing around the medications they take for their condition.

Which COVID-19 vaccines are effective for people with co-morbidities or underlying medical conditions?

There is no evidence to suggest that any specific COVID-19 vaccine gives a better level of immunity to people with co-morbidities. Any of the COVID-19 approved vaccines in your country should be suitable.

Even if the individual's current situation indicates that he/she may not have a strong response to the vaccine, it is still important to get vaccinated against COVID-19 to protect themselves at some level and their loved ones.

Vaccines do not reduce the risk of infection to zero. Some vaccinated people may still get infected. However, the vaccine will prevent them from developing severe forms of the disease, requiring hospitalizations, and dying.

Keeping other preventive measures (e.g. wearing masks, maintaining a physical distance of at least 1 meter distance from others and ventilation in indoor spaces) should be recommended even after vaccination to protect from COVID-19.

Should children with underlying health conditions get vaccinated against COVID-19?

Children with underlying health conditions are at increased risk for more serious COVID-19 disease. A potentially dangerous complication, the multisystem inflammatory syndrome, can occur in children infected by the COVID-19 virus and  lead to life-threatening problems.

Vaccination is a safe and effective way to protect them and it can help keep children from getting seriously sick even they get COVID-19.

If a child is 12 years or older and has an underlying health condition it is vital to receive one of the approved COVID-19 vaccines for children.


COVID-19 vaccines are safe for people with co-morbidities or immuno- comprised.

A misinformation that is circulating suggests that COVID-19 vaccines pose a great risk to people with underlying health conditions.

All vaccines have been rigorously tested, examined and found to be efficacious at preventing serious illness, hospitalization and death amongst a majority of people.

Multiple studies show that people with co-morbidities, including cancer, chronic kidney disease, dementia, diabetes, obesity, heart disease, HIV, AIDS, liver disease and others – are at higher risk of severe illness or death from COVID-19.

That's why it is so important for them to get vaccinated.

Even though the vaccine cannot decrease the risk of infection to zero, it offers significant protection against severe disease, hospitalization, and death.

Though vaccines may not respond as strongly as someone with a fully functioning immune system, they can protect people with co-morbidities from becoming very unwell.

Getting vaccinated is the safest way to build immunity without becoming ill with COVID-19 and passing it to others.


COVID-19 vaccines will not compromise individual's natural immune system.

One of the common COVID-19 vaccine myths is that COVID-19 vaccines wipe out or compromise individual's natural immune system.

A vaccine is a tool that educates the immune system about infection but without the risk of becoming sick from the actual virus.

It is like educating the brain about a certain topic in school – learning new things does not ‘wipe out’ or compromise what you already know, but adds to what is already known.

In the same way, COVID-19 vaccines cannot wipe out a person’s immune system or compromise it in any way, but add to the types of infections that the immune system will be able to fight off


As a healthcare worker, you play an essential role in COVID-19 vaccine acceptance, confidence and uptake amongst the general population as well as people with co-morbidities.

Patients may have questions about the safety and effectiveness of COVID-19 vaccines and your answers can influence their decisions to get vaccinated and be protected against infection.

Be open to hearing their concerns and take the time to address their questions.

Emphasize the benefits of vaccination while being honest about the potential side effects.

Reassure them by saying that serious side effects are very rare.

The common ones are usually mild and go away within a few days.

On the contrary, the side effects from a COVID-19 infection can last much longer.