Dear FR Docs: What is the test for Ebola infection?

10-9-14 | mamzelle

[Mamzelle]

News accounts come in about "symptoms" and "suspected cases"-- and then, nothing. No news forthcoming. Isn't there a lab test for Ebola? How long does the test take to run? Why aren't results published promptly, in public?

[tcrlaf]

The lab testing requires level4 bio-hazmat procedures, making it VERY expensive.

Which is why the CDC is trying hard to cut the number of tests it is running.

[bonfire]

I think someone said on another thread that lab tests take 48-72 hours?

Hope that person jumps in here.

[thackney]

http://www.cdc.gov/vhf/ebola/diagnosis/index.html

- - - - - -

http://www.cdc.gov/vhf/ebola/hcp/interim-guidance-specimen-collection-submission-patients-suspected-infection-ebola.html

Ebola virus is detected in blood only after the onset of symptoms, usually fever. It may take up to 3 days after symptoms appear for the virus to reach detectable levels. Virus is generally detectable by real-time RT-PCR from 3-10 days after symptoms appear.

Specimens ideally should be taken when a symptomatic patient reports to a healthcare facility and is suspected of having an Ebola exposure. However, if the onset of symptoms is <3 days, a later specimen may be needed to completely rule-out Ebola virus, if the first specimen tests negative.

- - - - -

Once the laboratory test is — once the blood is obtained, we usually can get — we usually get a test result back within 24 hours. Once we have it in the laboratory it’s very quick. It just takes a few hours. Between the time of the transport of the specimen to the laboratory. There’s a relatively fast turn around. I would say within a day people have the results.

http://www.cdc.gov/media/releases/2014/t1003-ebola-confirmed-case.html

[Jim Noble]

Isn’t there a test for Ebola? - Yes
How long does it take to run? - Depends on volume. It’s an exclusive CDC research product, it’s not like they can call Abbott and say “send us 10 000 more Ebola kits”. If they have a lot to do, it’s gonna be a long time.
Why aren’t the results published promptly? - They are, but there’s a backlog now.

[Uncle Miltie]

You seem informed. Are there known rates of false negatives?

[Mamzelle]

Watching the news—Bret just announced that the deputy in Texas is Ebola-free. Thanks all for the info. Wow, what a way to shut down the hospital for a whole city...

[Seeing More Clearly Now]

Since infected people take more than three weeks to show any symptoms, there should be a shutdown of flights and trains and buses from these countries and it should have been done already. These borders should be closed until the epidemic can be brought under control there.

[minnesota_bound]

test for Ebola infection?
If you see someone melting from the inside out and oozing all over the place. They have ebola.

[Mamzelle]

The first thing I thought of when they started talking about those laser-style thermometers was… they’ll just load up on NSAIDS just before hitting the airport. That’ll lower a fever at least a degree or two… Be interesting to know if Duncan did that very thing.

[hondact200]

Went to Mayo Clinic website regarding Ebola virus and Marburg Virus

Signs and syptoms typically begin within in five to 10 days of infection with Ebola or Marburg Virus. Early signs and symptoms include:
Fever
severe headache
Joint and Muscle aches
chills
weakness

Over time the symptoms become increasingly severe and may include:
Nausea and vomiting
diarrhea (may be bloody)
red eyes
raised rash
chest pain and cough
stomach pain
severe weight loss
bleeding, usually from the eyes and bruising (people near death may bleed from other orifices such as ears, nose and rectum.
internal bleeding

Ebola virus has been found in African monkeys, chimps and other nonhuman primates. A milder strain has been discovered in monkeys and pigs in the Phillipines. Marburg Virus has been found in monkeys, chimps and fruit bats in Africa

Tests
Enzyme linked immunosorbent assay (ELISA)
Reverse transcriptase polymerase chanin reaction (PCR)

[Jim Noble]

Screening out the sick ones isn’t that important.

It’s the ones from day+1 to day+21 after infection that must be kept out. They won’t have a fever or feel sick.

[Beowulf9]

I totally agree.

However, I posted this on an internet forum and this is the response I got:

“Why should we think at all before taking action that could result in trillion dollar losses and a Great Depression that would make the 1930s look like a boom. Just don’t let anyone or anything in or out of the country because we want to prevent about four deaths a year.”

[Babsig]

I work at a hospital in SC. There are no labs in our state certified to do the test so if we get a pt that needs tested we will have to send the specimen to the CDC in Atlanta...they told us due to travel and then run the test 24-48 hrs...the actual test and results dont take that long to perform.

[Vendome]

Lance the boils?

[therapsida]

Anyone know what strain it is?

How long it can live dried?

[stilloftyhenight]

I have read that it can live on surfaces for 6 days. Dead bodies still have the virus, which is why cremation is essential. Also, it shows up in the semen of survivors for 90 days.

[thackney]

Early confirmation can be difficult for detection. Positives seem to be for sure. Negatives in the first days need to be watched for development of symptoms until past 21 days. See below:

http://www.cdc.gov/vhf/ebola/hcp/interim-guidance-specimen-collection-submission-patients-suspected-infection-ebola.html

When Specimens Should Be Collected for Ebola Testing at CDC

Ebola virus is detected in blood only after the onset of symptoms, usually fever. It may take up to 3 days after symptoms appear for the virus to reach detectable levels. Virus is generally detectable by real-time RT-PCR from 3-10 days after symptoms appear.

Specimens ideally should be taken when a symptomatic patient reports to a healthcare facility and is suspected of having an Ebola exposure. However, if the onset of symptoms is <3 days, a later specimen may be needed to completely rule-out Ebola virus, if the first specimen tests negative.

[greeneyes]

Dr. Brantly’s first test was negative. They still kept him quarantined. His 72 hr. test was positive. It can take up to 72 hrs. to get enough virus for the test to detect.

Prior to Dr. Brantly, I heard several cases reported in West Africa where people tested negative, were sent home, got worse, came back to the hospital and tested positive. They were symptomatic and contagious during that time span.

Part of the reason for infection spreading more than it should have, if they had been quarantined instead of going back out into the community.

Hopefully they have told the guy to self-quarantine and continue to monitor his symptoms.

[Mom MD]

The PCR test is the most accurate and requires a few hours to run AFAIK. However, the time to get the specimen to the lab certified to run it and the actual times the lab runs the test all feed into how long it takes to get any given result back.