Ebola Virus DiseaseNCT05494801
Natural History, Disease Progression, and Long-Term Neurologic Sequelae of Ebola Virus Disease (EVD) Survivors in PREVAIL III
An observational study of Ebola Virus Disease, run by National Institute of Allergy and Infectious Diseases (NIAID) at 1 site in Liberia.
Trial summary
Background: Ebola virus disease (EVD) is a viral fever that can cause internal bleeding. The death rate from EVD is very high. In a 2014 outbreak in West Africa, 28,000 were affected and 11,000 died. EVD may also affect the brain and nervous system, but this is not well studied. Read more about this study
- Who is it for?
- Ages 18 to 99 yearsHealthy volunteers can take part
- Conditions the study is for
- Ebola Virus Disease
- How many people
- 203 participants
- Where
- 1 siteLiberia
- Study dates
- 25 Aug 2022to 25 Mar 2023
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 99 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: The study will include all of the participants who were involved in the Neurology Substudy of the PREVAIL III Ebola Natural History Study who are willing to join. The Neurology Substudy originally included 172 self-identified EVD survivors and 93 self-identified close contacts. Since inclusion into the PIII study and Neurology substudy, there is bound to be some attrition (with a few participants who have passed away, some who have moved away from the area, some who simply may no longer wish to participate, among other reasons for attrition).
Who may be able to join
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Stated willingness to comply with all study procedures and availability for the duration of the study
- Male or female, aged 18 or older
- Previous participant in the PREVAIL III Neurology Substudy, either as an EVD survivor or close contact*
- Ability of subject to understand and the willingness to sign a written informed consent document, or indicate consent with the help of visual aids in the case of illiterate participants.
- Close contacts are those who had a relationship with someone who survived EVD, but were never diagnosed with EVD themselves.
Who cannot join
- An individual who meets any of the following criteria will be excluded from participation in this study:
- At the time of enrollment, lacks consent capacity due to cognitive impairment that would make them incapable of understanding the explanation of the procedures in this study. Cognitive capacity to consent will be determined at the time of enrollment. Participants with mental disorders or those participants who are cognitively impaired yet still retain consent capacity will not be excluded.
- Is unable to comply with the procedures of the protocol.
- Has any condition in the judgement of the study staff that would make the volunteer unable to participate in the study.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Natural History, Disease Progression, and Long-Term Neurologic Sequelae of Ebola Virus Disease Survivors in PREVAIL III
Background:
Ebola virus disease (EVD) is a viral fever that can cause internal bleeding. The death rate from EVD is very high. In a 2014 outbreak in West Africa, 28,000 were affected and 11,000 died. EVD may also affect the brain and nervous system, but this is not well studied. People with EVD report headaches and mental status changes. Some rarely had strokes and seizures. Neurological issues can continue for years after people recover from the initial EVD infection.
Read more
Objective:
This is a natural history study to learn more about how EVD continues to affect survivors brain and nervous system after 5 years.
Eligibility:
People aged 18 years or older who participated in the PREVAIL III Neurology Substudy. Participants can be either an EVD survivor or a close contact. Close contacts are people who had a relationship with a survivor of EVD.
Design:
Participants will have 1 clinic visit.
They will have a physical exam. Their vital signs will be measured. They will also have a neurological checkup. The exam will assess their mental status. Their senses, reflexes, and coordination will be tested. They will be observed while walking to assess their gait. This exam will take about 1 hour.
Participants will have an interview. They will answer questions about any symptoms they have that may be affecting the brain or nervous system. This will take about 1 hour.
No other procedures will be performed during this visit.
Read the detailed description
Study Description:
The long-term neurological sequelae of Ebola virus disease are not welldescribed. Through the PREVAIL III (PIII) Ebola Natural History Study, a Neurology Substudy was undertaken to better understand the long-term neurologic sequelae of EVD, with 5 years of follow up planned. Unfortunately, due to the COVID-19 pandemic beginning in early 2020, the final study evaluations of the PIII Neurology Substudy participants were unable to be performed by study staff based in the United States. To better understand the long-term neurological sequelae of EVD survivors, we propose this single-visit observational study of the participants of the Neurology Substudy of PIII. We hypothesize that, although the EVD survivors neurological issues have improved over time, they still may have neurological sequelae even after over 5 years convalescence from EVD.
Objectives:
Primary Objective: To characterize the neurological sequelae in EVD survivors after over 5 years convalescence from EVD
Secondary Objectives: To harmonize data from PIII Neurology substudy to determine how the prevalence of neurological complaints and neurological exam abnormalities changed over time.
Endpoints:
Primary Endpoint: The prevalence of neurological complaints and neurological exam abnormalities in EVD survivors after 5 years or more of convalescence from EVD, in comparison to close contacts.
Secondary Endpoints: The change of neurological complaints and neurological exam abnormalities in EVD survivors over time.
- Conditions
- Ebola Virus Disease
- Keywords
- Emerging Infectious Disease, Hemorrhagic Fever, NEUROLOGIC SEQUELAE, Natural History
- Medical subject headings
- Hemorrhagic Fever, Ebola, Communicable Diseases, Emerging, Hemorrhagic Fevers, Viral
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Close Contacts | Close Contacts of EVD survivors, who were also previously in the PREVAIL III Neurology Substudy | |
| Patients (EVD Survivors) | Participants with a history of Ebola Virus Disease who were involved in the Neurology Substudy of the PREVAIL III Ebola Natural History Study |
What is being measured
The primary outcome is the main question the study is designed to answer.
Neurological Sequelae
To characterize the neurological sequelae in EVD survivors after over 5 years convalescence from EVD
Measured: 5 years post initial enrollment in PREVAIL III
Secondary outcomes (1)
Harmonize data
To harmonize data from PIII Neurology substudy to determine how the incidence of neurological complaints and neurological exam abnormalities changed over time
Measured: 5 years post initial enrollment in PREVAIL III
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Aug 2022
- Study start25 Aug 2022
- Primary completion25 Mar 2023
- Study completion25 Mar 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ebola Virus DiseaseStudies of the same condition, open and under way.
- More trials run by National Institute of Allergy and Infectious Diseases (NIAID)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Prospective
- Enrolment
- 203 participants (actual)
Sponsor and investigators
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
- Investigators
- Bridgette J Billioux, M.D., Principal investigator, National Institute of Allergy and Infectious Diseases (NIAID)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05494801
- Sponsor's protocol ID
- 10000727
- Other IDs
- 000727-I
- Status last verified
- Jul 2025
- First submitted
- 9 Aug 2022
- Last updated
- 18 Jul 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: We plan to share IPD that is clinically relevant and IPD that underlie results in publication.
Study at a glance
From the registry record, last updated by the sponsor on 18 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Natural History, Disease Progression, and Long-Term Neurologic Sequelae of Ebola Virus Disease Survivors in PREVAIL III
- ClinicalTrials.gov ID
- NCT05494801
- Acronym / sponsor ID
- 10000727
- Conditions
- Ebola Virus Disease
- Keywords
- Emerging Infectious Disease, Hemorrhagic Fever, NEUROLOGIC SEQUELAE, Natural History
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 203 participants (actual)
- Lead sponsor
- National Institute of Allergy and Infectious Diseases (NIAID)US National Institutes of Health
- Study start
- 25 Aug 2022 (actual)
- Primary completion
- 25 Mar 2023 (actual)
- Study completion
- 25 Mar 2023 (actual)
- First posted
- 10 Aug 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Background:
Ebola virus disease (EVD) is a viral fever that can cause internal bleeding. The death rate from EVD is very high. In a 2014 outbreak in West Africa, 28,000 were affected and 11,000 died. EVD may also affect the brain and nervous system, but this is not well studied. People with EVD report headaches and mental status changes. Some rarely had strokes and seizures. Neurological issues can continue for years after people recover from the initial EVD infection.
Objective:
This is a natural history study to learn more about how EVD continues to affect survivors brain and nervous system after 5 years.
Eligibility:
People aged 18 years or older who participated in the PREVAIL III Neurology Substudy. Participants can be either an EVD survivor or a close contact. Close contacts are people who had a relationship with a survivor of EVD.
Design:
Participants will have 1 clinic visit.
They will have a physical exam. Their vital signs will be measured. They will also have a neurological checkup. The exam will assess their mental status. Their senses, reflexes, and coordination will be tested. They will be observed while walking to assess their gait. This exam will take about 1 hour.
Participants will have an interview. They will answer questions about any symptoms they have that may be affecting the brain or nervous system. This will take about 1 hour.
No other procedures will be performed during this visit.
Detailed description
Study Description:
The long-term neurological sequelae of Ebola virus disease are not welldescribed. Through the PREVAIL III (PIII) Ebola Natural History Study, a Neurology Substudy was undertaken to better understand the long-term neurologic sequelae of EVD, with 5 years of follow up planned. Unfortunately, due to the COVID-19 pandemic beginning in early 2020, the final study evaluations of the PIII Neurology Substudy participants were unable to be performed by study staff based in the United States. To better understand the long-term neurological sequelae of EVD survivors, we propose this single-visit observational study of the participants of the Neurology Substudy of PIII. We hypothesize that, although the EVD survivors neurological issues have improved over time, they still may have neurological sequelae even after over 5 years convalescence from EVD.
Objectives:
Primary Objective: To characterize the neurological sequelae in EVD survivors after over 5 years convalescence from EVD
Secondary Objectives: To harmonize data from PIII Neurology substudy to determine how the prevalence of neurological complaints and neurological exam abnormalities changed over time.
Endpoints:
Primary Endpoint: The prevalence of neurological complaints and neurological exam abnormalities in EVD survivors after 5 years or more of convalescence from EVD, in comparison to close contacts.
Secondary Endpoints: The change of neurological complaints and neurological exam abnormalities in EVD survivors over time.
Study design
- Observational model
- Case-control
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Close Contacts | – | –Close Contacts of EVD survivors, who were also previously in the PREVAIL III Neurology Substudy |
| Patients (EVD Survivors) | – | –Participants with a history of Ebola Virus Disease who were involved in the Neurology Substudy of the PREVAIL III Ebola Natural History Study |
Who may qualify
- Ages
- 18 to 99 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- The study will include all of the participants who were involved in the Neurology Substudy of the PREVAIL III Ebola Natural History Study who are willing to join. The Neurology Substudy originally included 172 self-identified EVD survivors and 93 self-identified close contacts. Since inclusion into the PIII study and Neurology substudy, there is bound to be some attrition (with a few participants who have passed away, some who have moved away from the area, some who simply may no longer wish to participate, among other reasons for attrition).
Key inclusion criteria (6 listed)
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Stated willingness to comply with all study procedures and availability for the duration of the study
- Male or female, aged 18 or older
- Previous participant in the PREVAIL III Neurology Substudy, either as an EVD survivor or close contact*
- Ability of subject to understand and the willingness to sign a written informed consent document, or indicate consent with the help of visual aids in the case of illiterate participants.
Key exclusion criteria (4 listed)
- An individual who meets any of the following criteria will be excluded from participation in this study:
- At the time of enrollment, lacks consent capacity due to cognitive impairment that would make them incapable of understanding the explanation of the procedures in this study. Cognitive capacity to consent will be determined at the time of enrollment. Participants with mental disorders or those participants who are cognitively impaired yet still retain consent capacity will not be excluded.
- Is unable to comply with the procedures of the protocol.
- Has any condition in the judgement of the study staff that would make the volunteer unable to participate in the study.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Neurological Sequelae
Time frame: 5 years post initial enrollment in PREVAIL III
To characterize the neurological sequelae in EVD survivors after over 5 years convalescence from EVD
1 secondary outcome
Harmonize data
Time frame: 5 years post initial enrollment in PREVAIL III
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jul 2025.
- Individual participant dataSharing planned: Undecided. We plan to share IPD that is clinically relevant and IPD that underlie results in publication.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Bridgette J Billioux, M.D. principal investigator
National Institute of Allergy and Infectious Diseases (NIAID)
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Ebola Virus Disease, run by National Institute of Allergy and Infectious Diseases (NIAID) at 1 site in Liberia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Liberia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Neurological Sequelae (time frame: 5 years post initial enrollment in PREVAIL III). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jul 2025.