[Health] The Infectious Diseases Thread

esloan · Post by **esloan** » Sun Oct 05, 2014 3:38 am

Ralph-Wiggum wrote:I know it's probably hard to pinpoint, but any idea of the transmission rate of Ebola? Does coming into contact with fluids (let's say for example kissing) guarantee transmittance?

No. Not even close.

People are freaking out about this and its not really near a big a deal as its being made out to be. First some facts.

1. The current Ebola outbreak in West Africa has been going on for nearly a year. In that time, it has killed around 4,000 people. This is in countries that have a lack of doctors (Liberia, for instance, has 3.5 million people but only 122 doctors), a lack of basic medical necessities, horrible sanitation systems and outdated burial practices (many of the infected have been caregivers and those who dispose of the bodies).

Contrast that to the flu, which killed 36,000 people last year in the United States alone. With our superior health care system, no lack of doctors, all the medical necessities we need and all our practice fighting the flu, there were six times as many deaths due to the flu last year in the US than there were deaths in the last year of the Ebola Outbreak in West Africa.

2. Ebola is relatively difficult to spread. The reasons are many. First, it is not contagious until symptoms show up but the symptoms are so debilitating that once they do show up, the infected person is bedridden. He is not walking around exposing people. Secondly, Ebola is present in the bodily fluid of those infected but not all at once. It starts out in the blood, then moves on to urine, feces, sweat, saliva and vomit. However, by the time it shows up in the other bodily fluids the symptoms are so advanced that the infected person is almost certainly bedridden. This puts the threat of infection high for careless caregivers and people disposing of bodies but very low for everyone else.

The virus is deadly, there is no doubt about that, but it isn't something that is likely to become a pandemic. It spreads slowly and can be contained fairly easily. An infected person arrived in Lagos, Nigeria earlier this year. He was showing symptoms when he arrived and was not quarantined for four days after arrival. Lagos has eight million people, with a population density similar to New York City. It also has much poorer health care. Even then, an outbreak was contained. Nigeria has not had a new Ebola infection in over a month. Despite the high population and poor health care, there were only 20 cases total in Nigeria. In a highly populated urban center, it did not spread like wild fire. People just need to relax.

Isgrimnur · Post by **Isgrimnur** » Mon Oct 06, 2014 3:08 pm

Put Spain up on the board.

A nurse's assistant in Spain is the first person known to have contracted Ebola outside of Africa in the current outbreak.

Spanish Health Minister Ana Mato announced Monday that a test confirmed the assistant has the virus.

She had helped treat a Spanish missionary who contracted Ebola in West Africa. The missionary died after returning to Spain.

Zarathud · Post by **Zarathud** » Mon Oct 06, 2014 7:58 pm

Nobody expects the Spanish Ebola!

Matrix · Post by **Matrix** » Mon Oct 06, 2014 9:03 pm

I just spoke to a friend of mine, who is Biologist who specializes in this stuff. He said Ebloa becoming airborne is like saying ebola is developing nuclear program, and it will develop nuclear program sooner then airborne strain of Ebola. I thought that was pretty funny. Fear mongering media, is what they do.

Alefroth · Post by **Alefroth** » Mon Oct 06, 2014 11:44 pm

esloan wrote:Secondly, Ebola is present in the bodily fluid of those infected but not all at once. It starts out in the blood, then moves on to urine, feces, sweat, saliva and vomit. However, by the time it shows up in the other bodily fluids the symptoms are so advanced that the infected person is almost certainly bedridden. This puts the threat of infection high for careless caregivers and people disposing of bodies but very low for everyone else.

I'd like to use that in a debate. Do you have a source for it?

Stefan Stirzaker · Post by **Stefan Stirzaker** » Tue Oct 07, 2014 6:33 am

Read somewhere recently, PROMed I think, that the R of Ebola is 2. Measles in an unvaccinated population is like 18. So every 1 person will/could give it to 18 others in Measles. Ebola is 2. ALso they don't pass it on till they're symptomatic, so you get any contacts, lock them up for 30 days and you stamp on it. Of course if you don't have good contact tracing, then you could be in trouble.

msduncan · Post by **msduncan** » Tue Oct 07, 2014 8:12 am

How did the nurse in Spain get it? I would presume that 1) they knew the guy was coming 2) they prepared an isolation ward for him 3) they followed Western medical practices for safety and decontamination?

This one even confuses my wife, who is in the medical field and was the first to tell me months ago that Ebola is difficult to spread.

Ralph-Wiggum · Post by **Ralph-Wiggum** » Tue Oct 07, 2014 8:16 am

Matrix wrote:I just spoke to a friend of mine, who is Biologist who specializes in this stuff. He said Ebloa becoming airborne is like saying ebola is developing nuclear program, and it will develop nuclear program sooner then airborne strain of Ebola. I thought that was pretty funny. Fear mongering media, is what they do.

I'm not sure how you quantify the chance of Ebola becoming airborne unless you know the specific mutations that would be required. I'm sure it's pretty damn low, but the more Ebola spreads the more likely we will start to see more variants of the virus.

Ebola is actually not great at the main goal of any virus - spreading. You're not contagious until your symptoms start showing and once that happens its not too long until you die. That plus needing to be in direct contact of an infected person's fluids is probably why the R0 is so low compared to some other diseases.

Smoove_B · Post by **Smoove_B** » Tue Oct 07, 2014 8:18 am

They are insisting that protocol was followed:

"We know she entered the infected priest's room twice – once to treat him and once after he died to collect some of his things," Dr. Antonio Alemany, a health officials from the regional government of Madrid, said. "As far as we know, she was wearing a protective suit the whole time and didn't have any accidental contact with him."

I think they key here is, "As far as we know..."

I would see this all the time standing around watching people work in kitchens. After observing a violation, I'd ask them to walk me through what they were doing and they'd tell me what they should have been doing. I'd then point out what they actually did. It would not surprise me to learn doctors and nurses do the same thing.

EDIT: Yeah, here you go -- from Nurses say they are not prepared...

"Our healthcare workforce goes through so many pairs of gloves that they really don't focus on how they remove gloves. The putting on and the taking off doesn't occur with enough attention to protect themselves," he said.

Nurses say hospitals have not thought through the logistics of caring for Ebola patients.

msduncan · Post by **msduncan** » Tue Oct 07, 2014 8:18 am

Also, food for thought:

1989 Ebola outbreak was concluded to be airborne. Lucky for us, it happened to be a strain that humans couldn't catch.

So apparently that particular strain of Ebola had developed a nuclear program? Where should we look for it and do we need a magnifying glass to see the tiny little cooling towers?

Smoove_B · Post by **Smoove_B** » Tue Oct 07, 2014 8:30 am

No. There is general confusion among people that don't understand infectious disease terminology. Pull up a chair.

There are two broad classifications for how infectious agents are spread -- direct and indirect. Under direct transmission we have direct contact (biting, licking, skin-to-skin) and droplets (large, moist particulates of saliva and mucus). When someone coughs or sneezes (like say with a cold), they can eject those large moist droplets (direct transmission, droplet) from their lungs and mouth, launch them into the air and get them into your eyes, nose or mouth. Casually, people refer to that as "airborne" spread, but it's not technically true. The droplets are sensitive humidity and sunlight and follow gravity (i.e. arcing from the infected person's mouth and ultimately landing on the ground, a table, someone's eye, etc...).

The second type of spread is indirect. I'll only cover the first so I can keep it simple -- and that is indirect, airborne. This occurs when fine particulates (smaller than 10 microns) are generated and released into the atmosphere. It can happen with coughing and sneezing, but also say when a dentist is in your mouth drilling away at a tooth. Those fine particulates persist in the air -- because they are so tiny they "float" and can remain in a room or HVAC systems for hours. They're more resistant to environmental variables, though things like wind or HEPA filters will disperse them faster.

Measles is spread this way. Chicken pox can be spread this way. Both can also be spread via direct transmission droplets, but it's the indirect airborne route that makes them both highly infectious. If Ebola was truly an "airborne" disease, as mentioned earlier it's R0 would be much higher than 2. Measles and Whooping Cough have R0 values near 18 - spread through direct and indirect transmission. Influenza is around 5 - direct transmission.

So for that study you linked earlier, it's likely that there were large, moist droplets involved in the transmission. It's a study and example that keeps being raised over and over and I haven't seen a single respectable infectious control specialist in any way insist that it was indirectly spread. It's confusion over what "airborne" means to public health versus the general public.

Blackhawk · Post by **Blackhawk** » Tue Oct 07, 2014 10:02 am

Smoove_B wrote:
EDIT: Yeah, here you go -- from Nurses say they are not prepared...

"Our healthcare workforce goes through so many pairs of gloves that they really don't focus on how they remove gloves. The putting on and the taking off doesn't occur with enough attention to protect themselves," he said.

Nurses say hospitals have not thought through the logistics of caring for Ebola patients.

I used to train people in biohazard exposure and control, so this is something I'm hyper-aware of. It shocked me during my treatments how often nurses and doctors would do this. I've seen nurses get my blood on their gloves, pull off one glove, toss it, and pull off the other glove from the outside. I know I don't have anything bloodborne, but it still made me cringe. They stick their glovey fingers against their flesh, their fleshy fingers against their gloves - ugh.

Smoove_B · Post by **Smoove_B** » Tue Oct 07, 2014 10:15 am

Blackhawk wrote: I used to train people in biohazard exposure and control, so this is something I'm hyper-aware of.

Me too! Small world.

They stick their glovey fingers against their flesh, their fleshy fingers against their gloves - ugh.

Imagine you are watching someone in a kitchen making food go into the bathroom wearing latex gloves and they come out 3 minutes later wearing the same gloves and then go back to making sandwiches. "But I washed my hands!" was the common refrain. I used to see it happen all the time.

Isgrimnur · Post by **Isgrimnur** » Tue Oct 07, 2014 5:56 pm

That Spanish nurse? They've quarantined her husband and two others. And now they're going to kill her dog.

The response by Madrid raised the specter that pets could spread the disease. The city of Madrid got a court order to euthanize and incinerate the woman's dog over her and her husband's objections, according to the Associated Press. The dog is a mixed breed pooch named Excalibur.

The government said available scientific knowledge suggests a risk that the dog could transmit the virus to humans.

Dr. Tom Frieden, director of the Centers for Disease Control and Prevention, said in a news conference today, "We have not identified this as means of transmission," but declined to comment on the actions by Madrid officials.

Texas health commissioner David Lakey, who has said they are monitoring about 50 people who had contact with the Ebola patient in Dallas, said, "We are not monitoring any animals at this time."

Stefan Stirzaker · Post by **Stefan Stirzaker** » Tue Oct 07, 2014 6:04 pm

Killing the dog?? strange, never seen that for Ebola before. of course if the dog is close (licking face etc) it could of gotten it and it could spread it if it goes and licks others, but hell, put it in a kennel cage for a couple of weeks and problem solved.

Latest update from WHO. It is NOT airborne. http://who.int/mediacentre/news/ebola/0 ... er-2014/en

Kraken · Post by **Kraken** » Tue Oct 07, 2014 6:21 pm

I doubt that the dog posed any risk unless it was a fruit bat. But the story raises an interesting question: If there's little danger that the virus will evolve a different transmission method, is it more likely to adapt to a new host species? It made the jump at least once, from bats to humans, after all. Suppose it could infect mosquitoes or household pets -- what's the likelihood of that happening?

Smoove_B · Post by **Smoove_B** » Tue Oct 07, 2014 7:23 pm

Yeah, that's strange. Viruses jumping species is certainly possible, though usually we're looking at scenarios where there is prolonged exchange between the original animal reservoir/hosts and humans -- like influenza for example. For something to make that transition after a single outbreak would be...unprecedented. Remember - there are more people now with Ebola than we've ever seen. It's both exciting and scary -- but I'm confident when it's all under control we'll be able to advance general knowledge and ultimately end up in a better spot. Hell, the CDC released a detailed report today on how this outbreak was ultimately controlled in Nigeria.

What is amazing to me is that a Gallup poll was done and allegedly people are as afraid of Ebola as they were of H1N1 - two completely different diseases. I think that speaks more to a failure of public health communication than anything, though as a disease Ebola certainly is terrifying.

And yet...people still won't vaccinate themselves this year against influenza. It boggles the mind.

Kraken · Post by **Kraken** » Tue Oct 07, 2014 8:16 pm

I am concerned that the virus is encountering a lot of new environments in a short time. Lots of opportunities to swap proteins.

Smoove_B · Post by **Smoove_B** » Tue Oct 07, 2014 8:26 pm

Other than the article that came out earlier this summer suggesting there have already been ~300 mutations in the current strain, I'm not really well versed on Ebola genomics. Influenza? Slightly. But Ebola is a whole different ball of wax.

Octavious · Post by **Octavious** » Tue Oct 07, 2014 8:47 pm

Smoove you scare me. You should write a book or something.

Smoove_B · Post by **Smoove_B** » Wed Oct 08, 2014 9:14 am

Just a follow up to the Spanish nurse that everyone is losing their collective minds over -- turns out she wasn't using approved PPE for Ebola patient care and not following protocol:

Staff at the hospital where she worked told El País that the protective suits they were given did not meet World Health Organisation (WHO) standards, which specify that suits must be impermeable and include breathing apparatus. Staff also pointed to latex gloves secured with adhesive tape as an example of how the suits were not impermeable and noted that they did not have their own breathing equipment.

...

Staff at the hospital said waste from the rooms of both patients was carried out in the same elevator used by all personnel and, in the case of the second patient, the hospital was not evacuated.

In my experience, it's very rarely a single factor that causes a failure. Usually it's multiple steps or links in a chain that are broken. Seems to be the case here -- many mistakes were apparently made.

Smoove_B · Post by **Smoove_B** » Wed Oct 08, 2014 9:59 am

Kraken wrote:I am concerned that the virus is encountering a lot of new environments in a short time. Lots of opportunities to swap proteins.

I was thinking about this more last night and AFAIK, the Russians were never able to weaponize it during their research programs in the 70s - 90s (probably through early 00s even though they said those programs were dismantled). We know they tried...so...uh...that has to count for something, right? They were able to weaponize Marburg to a certain degree, but it's not exactly the same thing - not nearly as deadly. There was one scientist that accidentally injected himself in the lab and then was smart enough to isolate himself...while he continued to do research, writing down how he was feeling and what was happening to him as the virus slowly liquified his insides. I was looking to see if they had pictures of his blood-stained journal online, but alas they don't. After he died they took fluids from his body and decided the virus was awesome at killing people so they kept samples. There was a great documentary on PBS a long time ago about the whole thing -- the site is here if you're feeling you don't have enough to worry about.

I'm sure the FBI will be at my house soon enough just because of what I was searching for to get that link. Good times.

AjD · Post by **AjD** » Wed Oct 08, 2014 11:27 am

Thomas Eric Duncan has died

http://www.theguardian.com/world/2014/o ... ric-duncan.

Isgrimnur · Post by **Isgrimnur** » Wed Oct 08, 2014 12:09 pm

The US Army Medical Department Center and School has a wide variety of texts in PDF on ways that you can be injured, sickened or killed, including Medical Aspects of Biological Warfare. Chapter 13 is Viral Hemorrhagic Fevers.

Captain Caveman · Post by **Captain Caveman** » Wed Oct 08, 2014 3:59 pm

Oh fuck, here we go.

Patient with Ebola symptoms in Frisco had contact with Duncan

Frisco is a suburb north of Dallas.

If he had contact, why they hell is he up in Frisco going to a general urgent care facility?

Edit: It appears he's a sheriff deputy who had been in Duncan's apartment but never had direct contact with him. Fingers crossed that it's not ebola and this is just precautionary. If it is ebola, people are going to start freaking out (even more so) around here.

coopasonic · Post by **coopasonic** » Wed Oct 08, 2014 4:22 pm

Captain Caveman wrote:Oh fuck, here we go.

Patient with Ebola symptoms in Frisco had contact with Duncan

Frisco is a suburb north of Dallas.

...or as I like to call it "home."

Captain Caveman · Post by **Captain Caveman** » Wed Oct 08, 2014 4:38 pm

Where is Smoove? I want him to hold me.

msduncan · Post by **msduncan** » Wed Oct 08, 2014 4:48 pm

Smoove went to plan B and grabbed his bugout bag.

Isgrimnur · Post by **Isgrimnur** » Wed Oct 08, 2014 5:08 pm

Frisco? You mean where I'm having my wedding?

coopasonic · Post by **coopasonic** » Wed Oct 08, 2014 5:09 pm

3.6 miles from my house to the facility where this is going down.

Isgrimnur · Post by **Isgrimnur** » Wed Oct 08, 2014 5:14 pm

Preston or Main?

coopasonic · Post by **coopasonic** » Wed Oct 08, 2014 5:16 pm

Isgrimnur · Post by **Isgrimnur** » Wed Oct 08, 2014 5:17 pm

4.2 miles west of my wedding venue.

Kraken · Post by **Kraken** » Wed Oct 08, 2014 5:22 pm

Smoove_B wrote:
Kraken wrote:I am concerned that the virus is encountering a lot of new environments in a short time. Lots of opportunities to swap proteins.
I was thinking about this more last night and AFAIK, the Russians were never able to weaponize it during their research programs in the 70s - 90s (probably through early 00s even though they said those programs were dismantled). We know they tried...so...uh...that has to count for something, right?

Well, maybe. "Weaponize" implies gaining enough control over it to prevent blowback, which the virus itself isn't worrying about as it merrily swaps components with other bugs in the wild. I doubt that the Russians were trying to "teach" it to ride around in mosquito guts, for example. I realize that the odds against it acquiring a specific mutation like that are millions to one...but its opportunities do keep rising the longer and farther it spreads.

I don't know much about selection pressures on viruses. Ebola seems pretty successful in its current configuration.

Smoove_B · Post by **Smoove_B** » Wed Oct 08, 2014 9:47 pm

Captain Caveman wrote:Where is Smoove? I want him to hold me.

Hey professor, some of us have to work for a living instead of filling out grant applications.

I hadn't seen that - I'm just getting back to my PC now. When I saw that he died, my immediate thought was that people were going to go crazy, but that doesn't seem to be the case. I also thing we're about 1/2 though the magic window of when people should start getting sick based on exposure to him if its going to happen. These next 5 days will likely be critical in terms of where we go from here.

Kraken wrote:Well, maybe. "Weaponize" implies gaining enough control over it to prevent blowback, which the virus itself isn't worrying about as it merrily swaps components with other bugs in the wild.

Not quite. Weaponizing a bacteria or virus essentially means you make it more likely that it can be easily spread either in the environment or from person to person. Controlling blowback is more about making sure you have medication or vaccinations to prevent illness in your own people or troops. The best example I have of weaponizing a bio-agent was with plague before and during WW2. The Japanese Bioweapon Unit 731 researchers were trying to see if plague was a viable agent for debilitating an enemy. So they loaded up fleas with the bacteria and dropped them via bomb into China. Amazingly, it worked but it gave them bubonic plague -- awful, but not ideal if you're looking to cause the most damage. When Japan was defeated American and Russian scientists took all the research data from Unit 731 and figured out a way to remove the flea vector and aerosolize the bacteria to give the enemy pneumonic plague -- they weaponized it. Bubonic plague can change into pneumonic plague in some people, but it's not a 1:1 conversion. By aerosolizing the bacteria the dramatically increased the impact.

There were some rumors that the Russians were trying to genetically splice elements of smallpox with one of the hemorrhagic fever viruses, but I'm not sure that anything was ever proven.

Kraken · Post by **Kraken** » Wed Oct 08, 2014 10:15 pm

That's...fascinating. And horrifying. I know this much: When the gubmint tells me I need to get a "swine (or bird) flu vaccine" I'm first in line.

Blackhawk · Post by **Blackhawk** » Wed Oct 08, 2014 11:07 pm

Captain Caveman wrote:Where is Smoove? I want him to hold me.

I'd rather have someone hold me who doesn't work with infectious diseases for a living. Maybe a nice bricklayer.

Captain Caveman · Post by **Captain Caveman** » Wed Oct 08, 2014 11:19 pm

Blackhawk wrote:
Captain Caveman wrote:Where is Smoove? I want him to hold me.
I'd rather have someone hold me who doesn't work with infectious diseases for a living. Maybe a nice bricklayer.

Smoove's a brick... HOUSE.
He's mighty mighty, lettin' the ebola out.

J.D. · Post by **J.D.** » Thu Oct 09, 2014 10:25 am

Sounds like it's really unlikely the deputy has ebola as he's not showing all the classic signs (ie: no fever). He checked himself in as a precaution because he felt tired and had an upset stomach but no other symptoms.

J.D. · Post by **J.D.** » Thu Oct 09, 2014 10:26 am

Also, having a child in school I think I'm starting to get more concerned about this entovirus thingy floating around. Apparently the vast majority get the sniffles but there are some cases coming out now where kids are getting polio-like symptoms? WTF?