COVID-19 is a highly infectious disease caused by the novel coronavirus. It spreads through close personal contact with someone who has the virus.

In the majority of people, the symptoms of COVID-19 are relatively mild and do not require specialist treatment in a hospital. Mild symptoms may include a fever, a cough, a sore throat, tiredness, and shortness of breath.

However, people with diabetes may have a higher risk of developing severe complications, such as difficulty breathing or pneumonia.

Below, learn more about how COVID-19 may affect people with diabetes.

Man having a glucose test from a health professionalShare on Pinterest
The coronavirus may thrive in an environment of elevated blood glucose.

People with certain underlying medical conditions may have a higher risk of severe illness from COVID-19. These conditions include diabetes, heart problems, obesity, and chronic kidney disease.

Specifically, the available evidence suggests that people with type 2 diabetes have a higher risk of severe illness from COVID-19, according to the Centers for Disease Control and Prevention (CDC).

People with type 1 or gestational diabetes may also have an increased risk, but the data is less conclusive.

Symptoms of COVID-19 tend to appear 2–14 days after exposure to the virus SARS-CoV-2 and can include:

  • a fever
  • a cough
  • shortness of breath
  • fatigue
  • a headache
  • a new loss of smell or taste

In general, infections are more serious in people with diabetes. One reason is that diabetes affects the way the immune system works, making it harder for the body to fight viruses.

Also, diabetes causes high blood sugar levels, and the International Diabetes Federation observe that the novel coronavirus “may thrive in an environment of elevated blood glucose.”

Diabetes also keeps the body in a low-level state of inflammation, which makes its healing response to any infection slower.

High blood sugar levels combined with a persistent state of inflammation make it much more difficult for people with diabetes to recover from illnesses such as COVID-19.

Anyone with diabetes who notices symptoms of COVID-19 should contact a doctor as soon as possible.

The CDC cite research indicating that people with diabetes who develop COVID-19 may have a 7.3% risk of death from a COVID-related illness, compared with 5.6% for people who have cancer, for example.

However, by controlling their blood sugar levels well, people with diabetes can reduce the risk of getting severely sick from COVID-19.

More than 425 million people worldwide have diabetes. The two main forms are type 1 and type 2, and gestational diabetes can develop during pregnancy.

The sections below describe the types in more detail.

Type 1 diabetes

Type 1 diabetes usually develops in children and adolescents. About 10% of all people with diabetes have type 1.

Type 1 diabetes is an autoimmune condition that causes the immune system to destroy the beta cells of the pancreas. This results in little to no production of the hormone insulin.

A person with this condition needs to take insulin every day to keep their blood sugar levels healthy.

Ketones are chemicals that the body produces when it breaks down fat for energy. This can happen when the body does not have enough insulin. When ketones collect in the blood, they make it more acidic, which can be very dangerous.

The American Diabetes Association recommend that people with type 1 diabetes check for ketones every 4–6 hours when they are sick, when their blood sugar levels are higher than 240 milligrams per deciliter, or both.

Type 2 diabetes

Type 2 diabetes is the most common form, accounting for around 90–95% of all diabetes cases.

It keeps the body from making enough insulin or using any existing insulin efficiently, due to an issue called insulin resistance.

Most people with type 2 diabetes need medication to keep their blood sugar levels healthy. Eventually, they may also need insulin.

If a person with type 2 diabetes has any symptoms of COVID-19, they should let a doctor know.

Gestational diabetes

Gestational diabetes occurs during pregnancy and usually goes away after the pregnancy ends.

That said, people who have gestational diabetes are more likely to develop type 2 diabetes later in life.

Gestational diabetes also places a person at a high risk of complications if they develop COVID-19. Anyone with concerns should speak with their medical team about reducing the risk of infection and complications.

Learn more about COVID-19 and pregnancy here.

It may be more difficult than usual to obtain medicines, including diabetes medications, during the ongoing COVID-19 pandemic.

The CDC recommend that at this time, people with diabetes:

  • continue taking their medication, including insulin, as usual
  • test and keep track of their blood sugar levels
  • make sure that they have at least a 30-day supply of diabetes medications, including insulin
  • speak with a healthcare provider, such as by contacting the nearest community health center, to discuss any concerns about diabetes and COVID-19

During any illness, blood sugar levels can be more difficult to manage. The CDC also offer tips for managing diabetes when you are sick.

Viral infections, including the one caused by the novel coronavirus, can lead to serious complications in people with diabetes.

These complications may include:

Diabetic ketoacidosis

During periods of stress or illness, blood sugar levels may rise. Diabetic ketoacidosis (DKA) occurs when a person with diabetes does not have enough insulin available to deal with this elevation.

The body begins to break down fats for energy, resulting in a buildup of ketones in the blood. Ketones make the blood more acidic, which can quickly cause serious health problems.

DKA can cause a range of symptoms, including extreme thirst, nausea, rapid breathing, and fruity-smelling breath. Anyone who may have DKA should receive emergency medical care.


Pneumonia stems from an infection that causes inflammation of the air sacs of the lungs.

As the CDC note, people with diabetes who develop COVID-19 have a higher risk of developing a more severe form of COVID-19 — one that involves pneumonia.

Some studies suggest that everyone with diabetes who is older than 2 years should receive pneumococcal and annual influenza vaccinations.


If a person with diabetes has a fever from COVID-19, they are losing additional fluids. This can lead to dehydration, which may require intravenous fluids.

High blood sugar

Infections cause a stress response in the body, increasing the production of glucose. This results in higher-than-normal blood sugar levels.

As a result, a person may need extra insulin during an infectious illness. It is important to monitor blood sugar levels more frequently than usual, as they can suddenly spike.

The novel coronavirus spreads through tiny droplets that spray into the air when a person with the infection sneezes or coughs. Anyone within 6 feet, or 2 meters, of the person can inhale these droplets.

The virus can also transmit via surfaces that a person with the infection has touched.

People with diabetes can protect themselves from contracting the virus in the same way as everyone else, by:

  • frequently washing the hands with soap and water
  • using an alcohol-based hand sanitizer when soap and water are not available
  • avoiding frequently touched surfaces when possible
  • frequently disinfecting any potentially contaminated surfaces, such as countertops, tabletops, and door handles
  • not touching the eyes, nose, or mouth with unwashed hands
  • practicing physical distancing by staying 6 feet, or 2 meters, away from others in public
  • covering coughs and sneezes with a tissue or inner elbow — not the hands
  • avoiding all contact with people who are sick, especially if they have a fever, a cough, or both
  • keeping the immune system strong by getting at least 7 hours of sleep a night and reducing stress levels as much as possible
  • maintaining an adequate intake of food and fluids
  • trying to keep blood sugar levels in a healthy range

Mask recommendations

The CDC recommends that people who are not fully vaccinated wear cloth face masks in indoor public settings. If case numbers are high in the area, it may be best to wear a mask outdoors, as well.

This will help slow the spread of the virus from people who do not know that they have contracted it, including those who are asymptomatic. Note: It is critical that surgical masks and N95 respirators are reserved for healthcare workers.

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Anyone with diabetes who develops symptoms of COVID-19 should contact their healthcare provider as soon as possible.

While people with diabetes may have an increased risk of serious COVID-19-related illness, it is possible to reduce that risk by maintaining healthy blood sugar levels and taking steps to protect the body from infections.