Anemia is one of the common blood disorders that experts have associated with COVID-19. However, no research evidence yet demonstrates a direct causal relationship between both.

Having COVID-19 triggers an inflammatory response that may lead to serious consequences. Some research demonstrates the possible mechanisms for anemia in patients with COVID-19.

This article discusses anemia in people with COVID-19 and highlights studies that reveal the association between the two.

Coronavirus data

All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub for the most recent information on COVID-19.

Was this helpful?
a clinician is looking at a blood monitor with a patientShare on Pinterest
Phynart Studio/Getty Images

It is possible that COVID-19 can cause anemia in some people. A few studies found an association between the two conditions in hospitalized patients.

A 2021 study followed 206 participants with COVID-19 and found that 61% had anemia. In most cases, the anemia was mild and likely the result of an inflammatory response. However, the researchers report that the condition could be due to iron, multivitamin, and mineral deficiencies.

Similarly, a 2022 article reported a case series of six people with COVID-19 who had developed aplastic anemia and pure red cell aplasia. The latter is when a person’s bone marrow does not make enough red blood cells.

Medical experts associate autoimmune-mediated destruction of red cell precursors in the bone marrow as one of the possible causes of aplastic anemia and pure red cell aplasia in those with COVID-19. Red cell precursors refer to an earlier stage of the red blood cells.

Learn more about what can cause anemia.

There is no clear evidence indicating anemia is a risk factor for COVID-19. However, some studies have shown that individuals with anemia are at risk of severe COVID-19 and other complications linked with the infection. Therefore, people at risk of anemia need to be cautious about exposure to SARS-CoV-2, which is the virus that causes COVID-19.

Learn more about the at-risk groups for COVID-19.

The effect of COVID-19 on a person with anemia depends on many factors, including:

  • the severity of the anemia
  • immune response
  • other factors, such as a person’s overall health status

COVID-19 typically triggers an inflammatory response that can further reduce hemoglobin levels in a person with anemia.

When this level drops, the blood’s oxygen-carrying capacity reduces. It also affects tissue oxygenation, which refers to the process of oxygen molecules entering the body’s tissues. The extent of anemia can affect tissue oxygenation. Individuals with severe anemia will likely experience significantly lower tissue oxygenation than those with mild and moderate anemia. Doctors consider it severe anemia when the body’s hemoglobin levels are between 6.5 and 7.9 grams per deciliter. Oxygenation of tissues will also be lower due to lower red blood cells being available.

Therefore, those with anemia and COVID-19 are more likely to experience severe respiratory disease than nonanemic individuals.

What research says

A 2021 study reported that patients with anemia and COVID-19 had lower oxygen saturation and experienced breathing difficulties. Also, the researchers noticed kidney and heart dysfunction among hospitalized patients with anemia and COVID-19.

Another 2022 study in India reported that out of 784 COVID-19 patients who required intensive care, 507 patients who died had various degrees of anemia. This study highlights that there is indeed a link between anemia and COVID-19 severity and that having anemia may harm a person’s outlook. The researchers also state that measuring hemoglobin levels can help doctors treat people with both conditions. That said, more research is necessary to understand this relationship.

Learn more about how COVID-19 affects the body.

There are different treatment options for people with anemia and COVID-19. Generally, these strategies aim to target the underlying cause of the anemia.

For mild COVID-19 and mild anemia, the following measures can be helpful:

  • using nonsteroidal anti-inflammatory drugs (NSAIDs) to ease the inflammation and relieve pain
  • adequate bed rest
  • adequate fluid intake

Also, some people with mild or moderate anemia and iron deficiency may benefit from taking iron-containing multivitamin supplements.

Severe disease

Blood transfusion is a treatment option for individuals with severe anemia and COVID-19. Typically, those with severe disease are likely to experience a significant drop in the blood oxygen saturation levels, which may be life threatening.

The doctor may also prescribe an antiviral medication, especially for those with severe COVID-19. Reducing the viral load can help decrease the degree of anemia due to inflammation.

Individuals with severe COVID-19 and anemia may require hospital care for close monitoring and treatment.

Learn more about when to seek emergency help for COVID-19.

The recovery of people who have anemia with COVID-19 varies, and the following factors can play a role:

  • age
  • immunity level
  • having other chronic medical disorders

Within the recovery period, there is a risk of getting COVID-19 again, even in people with no further clinical signs of the disease. Recurrent COVID-19 could also affect the timeline for recovery.

A 2020 study reported that iron homeostasis (or balance) might take at least 2 months after COVID-19 to revert to expected levels. During the recovery period after COVID-19, the individual may also experience lung dysfunction and changes in their physical health or vitality.

Learn more about the possible long-term effects of COVID-19.

Anemia is a demonstrated risk factor that may worsen the severity and outcomes of COVID-19.

People with anemia and COVID-19 are at risk of respiratory diseases, such as pneumonia, and organ dysfunction, which can affect survival rates. According to a 2021 review study, the researchers associated anemia with a 70% risk of short-term death among 9,623 hospitalized patients.

That said, the outlook of anemia in those with COVID-19 will also differ according to the severity of both conditions.

A person with anemia is vulnerable to severe COVID-19. A few reasons may be responsible, including having low hemoglobin levels. Several studies also suggest anemia can occur when someone has COVID-19, and this is likely due to inflammation, multivitamin deficiency, and autoimmune response.

Treating anemia in COVID-19 depends on the severity of the anemia and COVID-19. Medications, such as iron multivitamins and NSAIDs, may help in mild cases, but blood transfusion could be necessary for more severe cases.

Recovery from anemia after COVID-19 varies due to the potential risk of reinfection with SARS-CoV-2. The outlook of people with both conditions depends on the person’s age, health status, and other factors.