Discover what the latest science from RECOVER means for our ability to understand, diagnose, prevent, and treat Long COVID.
This page contains descriptions of findings from RECOVER research studies. These descriptions use plain language and a format that is easy to understand.
If you want to learn more about the scientific discoveries described here, you can also browse and search the complete list of RECOVER Publications.
The researchers leading the RECOVER-VITAL clinical trial published a paper describing the study’s design in the journal Clinical Trials. RECOVER-VITAL tested 2 different treatment durations of nirmatrelvir/ritonavir, an antiviral medication commonly used to treat mild to moderate COVID-19. The trial evaluated whether the antiviral could improve Long COVID symptoms including brain fog, dizziness, fast heart rate, fatigue, and low energy. Researchers believe these symptoms may be caused by viral persistence, which occurs when the virus that causes COVID-19 remains in the body and disrupts organs or the immune system.
The design paper outlines how the trial was organized and conducted to produce accurate results. The authors describe how the protocol was developed, as well as the development of the primary and secondary outcomes. The authors also describe the study’s broader goals: advancing understanding of Long COVID symptoms, strengthening clinical trial design, and evaluating potential treatments at a time when limited evidence was available.
The researchers leading the RECOVER-AUTONOMIC clinical trials recently published a paper describing the study’s design. The trial was a multicenter, randomized, double-blinded, placebo-controlled, platform trial employing a flexible, adaptive design. The trial tested 3 possible interventions, or study treatments, for postural orthostatic tachycardia syndrome (POTS), an autonomic nervous system disorder that can develop in some people with Long COVID. These study treatments included intravenous immunoglobulin (IVIG), ivabradine, and coordinated non-drug care.
The design paper includes details on the development of the study protocol and determination of the outcomes studied. Results from RECOVER-AUTONOMIC will be shared in the coming months.
This RECOVER study looked at whether social determinants of health (SDOH) affect the risk of children developing Long COVID after having COVID-19. SDOH are the conditions in the places where people live, learn, work, and play that can affect health, such as safety or access to food, education, and healthcare. Researchers looked at survey data from more than 4,500 children. The surveys included questions about family income, access to food, school life, and how children are treated by others. The study found that children whose families struggled to pay for basic needs, like housing and food, were much more likely to have Long COVID. However, children in families who always had access to food, even if they struggled to pay for other things, were less likely to have Long COVID. This study also found that children who felt they were treated worse than others or parents who did not have enough support from friends and family had a higher chance of Long COVID. This RECOVER study is important because it shows that access to food and a supportive community may play a key role in protecting children from developing Long COVID.
In this study, researchers used RECOVER data and blood samples to learn more about the biological mechanisms (changes in the body) that can lead to the development of Long COVID symptoms.
The researchers analyzed health information and blood samples collected between 2020 and 2021 from a group (cohort) of 142 people not taking part in RECOVER studies. This cohort included people who did and did not have COVID-19 as well as people experiencing symptoms of Long COVID. To ensure the accuracy (validate) their findings from the study of the 2020-2021 cohort, researchers compared them to findings from a different cohort that also included people without COVID-19, people with COVID-19, and people with Long COVID. The people in this cohort also took part in a RECOVER clinical trial between 2022 and 2024.
Researchers performed multiple tests on blood samples collected from both cohorts and combined those analyses with health data collected from cohort members. The combined test results and health data suggest that Long COVID is associated with changes to the body’s immune system. Among people taking part in the study, the most important of these changes were chronic (long-lasting) inflammation and T cell exhaustion. While inflammation can indicate that the immune system is overreacting and even attacking healthy parts of the body, T cell exhaustion means the immune system has a reduced ability to fight off infections like SARS-CoV-2, the virus that causes COVID-19. Evidence of inflammation and T cell exhaustion appeared in multiple types of blood sample analysis data, including data about how individual immune cells behave and how a person’s body creates the proteins it needs to repair damage. Researchers also found that people who experienced inflammation during an initial (acute) SARS-CoV-2 infection were most likely to develop symptoms of Long COVID like pain, cough, brain fog, and fatigue.
The findings suggest that the immune system may stay activated, and sometimes in a weakened state, for a long time after a person has had COVID. These findings are important because they could inform future studies on diagnosing and treating Long COVID.
This RECOVER paper combined research findings, patient experiences, and possible explanations about how the body works to understand how different germs and health factors might play a role in Long COVID. Researchers looked at how having a viral, bacterial, or fungal infection before, during, or after COVID-19 might make someone more likely to develop Long COVID. The combined information suggests that these infections can confuse the immune system, making it attack healthy cells or cause problems to the body’s organs. For example, the stress of fighting SARS-CoV-2, the virus that causes COVID-19, might “wake up” old viruses that were dormant (asleep or inactive) in the body, which can make a person sicker or more likely to develop Long COVID. This paper is important because it shows that Long COVID is complex and may involve different germs that change the body’s responses to infection. By learning more about these connections, researchers hope to find better ways to test for and treat Long COVID in everyone.
In this RECOVER study, researchers wanted to find out how Long COVID symptoms change over 15 months. To do this, researchers studied 3,659 adults who had COVID-19 before joining the RECOVER study or while they were enrolled. Researchers found that Long COVID does not look the same in everyone. Instead, people’s Long COVID symptoms usually fell into 1 of 8 different patterns over time. While most people felt better after recovering from COVID-19, about 1 in 20 participants had symptoms of Long COVID that lasted throughout the entire study. About 3 in 25 participants with Long COVID had symptoms that came and went. Other participants did not have Long COVID symptoms early on but started having health problems many months after having COVID-19. These findings show that doctors should continue monitoring patients for a long time after they have COVID-19 because their symptoms can stay, come and go, or start several months after getting sick. Understanding these patterns will help researchers find better ways to prevent and treat Long COVID in different groups of people.
The RECOVER-NEURO Cognitive Dysfunction (BrainHQ, PASC-CoRE, & tDCS) clinical trial tested 3 non-drug treatments to see if they improved thinking, focus, and memory for people with Long COVID. The 3 treatments included:
A unique aspect of RECOVER-NEURO was its decentralized design, enabling 328 adults across 22 U.S. sites to participate in this research despite living with Long COVID symptoms. The participants completed most study activities remotely during a 10-week study period. Some participants were assigned to a treatment group and received one of the three active treatments (BrainHQ, PASC-CoRE plus BrainHQ, or tDCS-active plus BrainHQ). Other participants were assigned to a comparison group and received either the BrainHQ active comparator or tDCS-comparator plus BrainHQ. Researchers found that all of the treatment groups and comparison groups reported similar results in their improvement in thinking, focus, and memory. All participants reported some improvement over time and many said they felt better overall after they completed their assigned treatment, even though no one treatment outperformed other groups, including the comparison groups.
In this RECOVER study, researchers wanted to find out if adults with a serious mental illness (SMI)—like major depression, schizophrenia, or bipolar disorder—were more likely to develop Long COVID. To do this, researchers looked at the electronic health records (EHRs) of more than 1.6 million adults across the US. They found that adults with an SMI had a higher chance of developing Long COVID than adults without an SMI. This may be because SMIs can cause stress and problems with a person’s immune system, which could make them more likely to develop long-lasting symptoms after having COVID-19. Among adults with an SMI, higher rates of Long COVID were seen in older people, non-Hispanic Black and Hispanic people, people with public health insurance, people with other long-term illnesses like heart disease or diabetes, and people who were hospitalized after they got COVID-19 for the first time. This study is important because it shows that healthcare teams should look at SMIs in addition to other risk factors to help prevent and treat Long COVID.
This RECOVER study looked at whether the COVID-19 vaccine could help protect teenagers ages 12–17 from developing Long COVID. Researchers studied 1,231 teenagers enrolled in RECOVER who had confirmed COVID-19. Some were vaccinated before they got COVID-19 (724 teenagers), and some were not (507 teenagers). Researchers made sure the 2 groups were similar in terms of sex, date when they got COVID-19, and when they joined the study to make comparisons fair. They found that teenagers who were vaccinated in the 6 months before getting COVID-19 for the first time were about one-third less likely to get Long COVID. This study is important because it shows that COVID-19 vaccines, which were previously found to prevent getting COVID-19, can also protect against developing Long COVID in young people.