Important update: Healthcare facilities
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Special Clinical Considerations

Special Clinical Considerations
Updated Jan. 4, 2024
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People who are Moderately or Severely Immunocompromised


People with immunocompromising conditions and people who take immunosuppressive medications or therapies are at increased risk for severe outcomes with COVID-19, including hospitalization, intensive care unit admission, mechanical ventilation, and death.30,31 Studies show that people with a hematologic or solid organ cancer, hematopoietic stem cell or solid organ transplant, or who are taking immunosuppressive medications can experience lower vaccine effectiveness than those who are immunocompetent.32-34 However, studies suggest that administration of a third vaccine dose as part of the primary series and booster doses increases immune response and protection against severe illness.35-37


Additionally, several therapeutics, including the oral antiviral medication ritonavir-boosted nirmatrelvir (Paxlovid), the intravenous antiviral remdesivir, and the oral antiviral molnupiravir (Lagevrio), are beneficial in this population for early treatment of COVID-19. Treatment is best if initiated as soon as possible after diagnosis and within 5 to 7 days after illness onset.

The FDA has issued an EUA to permit the emergency use of COVID-19 convalescent plasma with high titers of anti-SARS-CoV-2 antibodies for the treatment of COVID-19 in patients with immunosuppressive disease or receiving immunosuppressive treatment, in either the outpatient or inpatient setting. For more information, please see the FDA Fact Sheet for Providers. The NIH COVID-19 Treatment Guidelines also provide recommendations on who should be considered for this treatment.


Clinical information on the treatment of patients with immunocompromising conditions can be found on the NIH Treatment Guidelines for Non-hospitalized Adults. There are additional guidelines about COVID-19 vaccines, and prioritization for therapies specific to this population.


See related pages

Pregnancy and Recent Pregnancy


Pregnant and recently pregnant people (for at least 42 days following the end of pregnancy) are at increased risk of severe illness from COVID-19, including hospital admission, intensive care unit admission, receipt of invasive mechanical ventilation, extracorporeal membrane oxygenation, and death, compared to people who are not pregnant.3,4 Race and ethnicity,4-6 older maternal age, occupation in healthcare, and number and type of underlying conditions are associated with severe COVID-19 illness among pregnant people.4,7,8

Data from meta-analyses9-12 and observational studies2,8,13 suggest that pregnant people with COVID-19 (compared to pregnant people without COVID-19) are at increased risk of preterm birth and stillbirth and might be at increased risk of pregnancy complications, including pre-eclampsia.

Increased risk for postpartum complications, including hospital readmission, has been observed among recently pregnant people with COVID-19 compared to recently pregnant people without COVID-19.14,15 However, methods for defining the period of recent pregnancy vary from study to study. While some studies include people with COVID-19 immediately after delivery, others include people with COVID-19 up to at least 42 days (6 weeks) after a live birth or pregnancy loss.


The COVID-19 Treatment Guidelines Panel recommends against withholding treatment for COVID-19 from pregnant or lactating individuals because of theoretical safety concerns. For more information on the treatment of COVID-19 in pregnant people, see the NIH Treatment Guidelines on Special Considerations in Pregnancy.


In general, the therapeutic management of pregnant people with COVID-19 is the same as management of people who are not pregnant.

Post-COVID Conditions or Long COVID


Post-COVID conditions, also known as Long COVID refers to a range of new or persistent symptoms and health conditions that may affect multiple organ systems and are present 4 or more weeks after acute SARS-CoV-2 infection. Post-COVID conditions are challenging to study because they include a wide range of physical and mental health consequences that are new, returning, or ongoing. For more information on Post-COVID Conditions including diagnosis, testing, management, vaccination recommendations and research, visit CDC’s:

Multisystem Inflammatory Syndrome


Multisystem inflammatory syndrome (MIS) is a rare but serious condition usually occurring 2-6 weeks after SARS-CoV-2 infection. MIS is characterized by systemic inflammation that may affect the heart, lungs, kidneys, brain, skin, eyes, gastrointestinal, or other organ systems. MIS can occur in children (MIS-C) or adults (MIS-A). The Council for State and Territorial Epidemiologists and CDC have developed surveillance case definitions for MIS-C, with an updated CDC case definition [PDF – 13 pages] for MIS-C effective January 1, 2023.47


CDC provides a case definition for MIS-A. Patients with MIS-A are often young adults who present with fever, elevated laboratory markers of inflammation, hypotension or shock, cardiac dysfunction, shortness of breath, and gastrointestinal symptoms.40-42

Diagnosing MIS-A can be challenging as patients may have experienced an unrecognized asymptomatic or mild initial SARS-CoV-2 infection. Additionally, the signs and symptoms of MIS-A overlap substantially with other conditions such as acute COVID-19 in adults.41,42 When evaluating for MIS-A it is important to consider alternative diagnoses.


Treatment recommendations have not yet been developed for MIS-A; however, studies have reported the use of steroids, intravenous immunoglobulins (IVIG), other immunomodulatory medications, and supportive care for treatment.40-42 Vaccination is also considered beneficial for patients who have had MIS-A. For more information on vaccination recommendations for patients with a history of MIS-A, see CDC’s Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Approved or Authorized in the United States.

Consider reporting cases of MIS-A to your local, state, or territorial health department. For more information, see CDC’s MIS-A Information for Healthcare Providers.

Pediatric Populations


The initial clinical presentation of COVID-19 in children can include fever, cough, or other respiratory symptoms; many children also experience gastrointestinal symptoms, including nausea, vomiting, or diarrhea.16,17 Viral tests are recommended for diagnosing COVID-19 in children. Children who develop severe illness can develop abnormal vital signs and markers of severe inflammation once hospitalized.18 A study of over 10,000 hospitalized children found that lower blood pressure, higher heart and respiratory rates, and abnormal markers of inflammation, including D-dimers and ferritin, were associated with severe illness in children.18

Studies suggest that many children experience asymptomatic or mild illness, but some children can experience severe COVID-19 illness requiring admission to the hospital or ICU, or use of invasive mechanical ventilation, and some die.19,20 Like adults, children with underlying medical conditions, including obesity, diabetes, and cardiac, lung, and neurologic disorders, have increased risk of severe COVID-19.18,19,21,22 Studies of hospitalized children with COVID-19 found that having more than one comorbidity is associated with an increased risk of severe illness.22,23

While increasing age is the strongest risk factor for severe COVID-19 illness among adults,1 among children, infants (<12 months of age) may be at increased risk for severe illness.24,25 In addition to individual risk factors, the COVID-19 variant that is circulating at the time of infection could have an impact on disease severity. Compared to prior periods, studies of COVID-19 in the pediatric population during the Delta predominant period found increased rates of hospitalization.26,27 Further increases in overall number of pediatric hospitalizations were observed during the Omicron predominant period, particularly for children under the age of 5 years. Despite this, pediatric patients experienced less severe disease during the Omicron period than in previous waves.25,28,29


Some of the medications authorized for the treatment of COVID-19 in adults have been authorized for use in children. For information on medications that are authorized for use in children in ambulatory and hospital settings, see NIH COVID-19 Treatment Guidelines.


For information on recommendations for clinical management, see the American Academy of Pediatrics Management Strategies in Children and Adolescents with Mild to Moderate COVID-19.

Post-COVID Conditions in Children

Children experience post-COVID conditions, but they appear to be affected less frequently than adults. Estimates of the proportion of children who experience COVID-19 and later develop post-COVID conditions range widely.45,46 Many studies suggest that older adolescence, female sex, and underlying medical conditions are frequently associated with persistent symptoms.46,47  Studies of post-COVID conditions in children report varying symptoms and conditions,46-48 and many studies report symptoms in similar frequencies for children who were infected with SARS-CoV-2 and those who were not infected.45,49 Commonly reported symptoms can include fatigue, smell and taste disturbances, and myalgia or arthralgia.46-48

COVID-19 vaccination has been shown to be protective against MIS-C,38-40 and according to expert opinion, COVID-19 vaccination may benefit children who have had MIS-C by reducing risk of severe disease and potential recurrence of MIS-C after re-infection. For more information on vaccination recommendations for patients with a history of MIS-C, see CDC’s Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Approved or Authorized in the United States.

Post-COVID conditions are challenging to study because they include a wide range of physical and mental health consequences that are new, returning, or ongoing.

Table of Contents


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