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Ebola Vaccine Trials Forcing Tough Choices
An anonymous reader writes: Medical researchers hope an experimental vaccine for Ebola can help protect against infection and slow the spread of the disease. Efficacy trials for the vaccine begin in a few months, and it's forcing some difficult decisions for health care officials. The first test will involve front line health care workers, who, as a group, are at the gravest risk of infection. But every trial needs a control group, and scientists are bitterly divided over whether the vaccine should be withheld from a portion of those putting their lives on the line to protect the rest of us. Development of the vaccine has been vastly accelerated already, due to the virus's spread and its mortality rate.
"The leading alternative is a design known as step-wedge, which essentially uses time to create a control group. In this design, researchers take advantage of the inescapable reality that large-scale trials can't give everyone the vaccine on the exact same date; they compare the rates of infection in people already vaccinated with those who have yet to receive the shots. Barney Graham, a virologist ... says "people are more comfortable" with the step-wedge design, because everyone in such a study would get the Ebola vaccine. But statistically speaking, this design makes it more difficult to determine the vaccine's worth, and it takes longer." NY Mag has a related story summarizing the treatments currently being used to fight Ebola.
"The leading alternative is a design known as step-wedge, which essentially uses time to create a control group. In this design, researchers take advantage of the inescapable reality that large-scale trials can't give everyone the vaccine on the exact same date; they compare the rates of infection in people already vaccinated with those who have yet to receive the shots. Barney Graham, a virologist ... says "people are more comfortable" with the step-wedge design, because everyone in such a study would get the Ebola vaccine. But statistically speaking, this design makes it more difficult to determine the vaccine's worth, and it takes longer." NY Mag has a related story summarizing the treatments currently being used to fight Ebola.
They known the mortality rate of ebola when untreated.
They can find out the mortality rate effect when vaccinated.
What does it matter if they can't measure the amount of the placebo effect in this particular case? Hell, if magic capsules of sugar help people with Ebola and the vaccine doesn't, then give them that.
The difficulty in determining the effectiveness of the vaccine when you give it to everyone is dependant on how effective it is. If it reduces the chances of exposure resulting in infection by 10%, then yes, it will be tough to show that it's not useless. However, if it reduces the chances by 90%, it will be quite obvious.
Experts: Ebola Vaccine At Least 50 White People Away
"Development of the vaccine has been vastly accelerated already, due to the virus's spread and its mortality rate." Ebola isn't new. What's new is that there's now a very real chance of the infection spreading to countries where white people live. Hence the "vastly accelerated" development.
Every year is the same, some rare and potential deadly desease has an outbreak and the big pharma companies have some experimental UNPROVEN cure.
The same happened H1N1, H5N1, SARS and all that crap that only made phamaceutical laboratories richer.
Are you serious?, really?, Sex with animals is your best guess?
Until them, we should call it something along the lines of "hopefully dead ebola virus that we think might make you immune to live ebola".
If we call it that, then no one will complain about not getting it.
excitingthingstodo.blogspot.com
They are doing more about it because of the scale of the current problem.
That scale is also the reason a person in the US got infected.
The scale is likely the result of a mutation in the virus, there's a much longer incubation time now.
Thank you, Bradley Manning, Edward Snowden and so many others, for courageously defending humanity, my freedom and more!
No, the rush to create a vaccine coinicdes with the latest outbreak, which has 10 times (and counting) the number of infected as the next largest outbreak. More importantly, all previous outbreaks were local and contained reasonably easily. This is the first time Ebola is getting away from us; in previous cases we had the option of containing it and letting it run its course, now it looks like that may no longer be enough.
And before this outbreak happened, research into vaccines was already taking place. Of course the urgency is somewhat higher now, since we may be looking at a global epidemic. This has nothing to do with ohmygodanAMERICANgotinfected.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
This latest outbreak has already infected more than in the entire history of the virus prior to it. There hasn't been a great deal of effort, because there simply hasn't been a great deal of need. It takes time for labs to spool up against an outbreak, and the fact that new treatments are coming down the pipeline right around the same time the virus starts spreading to other countries is purely coincidence.
It's not impossible to know the impact, see regression discontinuity for an example. The issue is effectiveness. Do we want to save some people now and learn less, or save lots of people later but risk some now?
Your study is doomed already. Ask the researchers that tested AIDs drugs in the 80s. People will share pills in an attempt to be sure they got the right thing. They'll buy them on the black market. They'll join multiple studies and take herbal remedies. When death is on the line people will do what they need to do to survive, your study be damned. So just give the drug to them all and save your study work for when there isn't an epidemic going on.
According to the alert on CNN, he has just died from Ebola.
Taking guns away from the 99% gives the 1% 100% of the power.
That scale is also the reason a person in the US got infected.
A clarification; No person in the US has gotten infected, as far as I know. The only US cases are those infected outside the US and then traveling to the US. There was a nurse in Spain that got infected from a patient, otherwise I don't think there are any known infections that happened outside of Africa.
I suspect you're trolling, but since I've seen more than statements of this kind of ignorance lately, here goes: there are other bodily fluids than semen. Blood, saliva, mucus, even perspiration. People who are sick tend to cough and sneeze a lot, spraying the air with their bodily fluids. Ever seen a slow motion video of someone sneezing? The virus doesn't have long to survive outside the host, but half a minute is all it needs. Worse, it's become more virulent than it was before.
I predict a vaccine is only 50 white people away
The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.
It's not even coincidence, it's the only way human trials could run. A vaccine could only have been developed with pigs, monkeys and whatever else, which would put them in the lab until human infection arose.
Dear AC, if you under fourteen years old nor drunk/high right now, and at any point in your life ask yourself the following question: "Could it be possible that this makes no sense to me because I'm stupid?" Be safe in the knowledge that the answer to your quandary is a resounding "Oh my fucking God! YES!"
Well, we can't just sit back and let white Americans suffer.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
By yet another secret executive order by Hunta Strong Man Barak Hussein Obama, all U.S. citizens returning to all U.S. airports from any foreign country will be arrested on entry, have their temperature taken by anus or penis thermometer and given an extensive questionnaire that will require three days quarantine at the airport at their own expense or face death by stationed U.S. Army units on site.
Obama yet again launches a war against his most hated of enemy, the legal U.S. citizens of the U.S.
Funny that ebola has been in existence in the modern world since the 70s, yet only now this is coming to light. Oddly enough, this is perfectly timed with someone in the US getting infected.
"Shit, this is on OUR turf now!??! Better do something about it!"
There is a causal relation driving this correlation, but it's not the one you cynically postulate. Both the appearance of someone in the US with the disease and the attempt to create a vaccine have been caused by the scale of the latest outbreak.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
Don't want to be the asshole, but OMGANAMERICANGOTINFECTED is the best way to get money thrown at the problem. Why would someone throw their own money at something that has little to no effect on them, something they may not even be aware of as a serious problem. Ebola may have a high mortality rate, but it is not wide spread. It is not a huge problem and is probably not all that deserving of the attention it is getting as compared to other diseases that could use some preventative research.
Need an un-vacinated control group. How about the continent of Africa. Enough people for your test group?
The conservatives seem to want to turtle and ban all travel from those nations ... which would, of course, be a death knell for any aide workers traveling there to help out. They seem to think that will prevent it from spreading when, in fact, that's just increasing the odds that ebola spreads more rapidly inside Africa and ensures that it becomes a global catastrophe. But that's pretty typical of conservative ideals. I'm still waiting on those 'trickle down' economics to get to me.
Some of the conservatives in the South are real dirtbags. It's really quite ridiculous.
Just inject the people who are already infected with Ebola, with the "vaccine". If they are all cured, then it passes.
Oddly enough, that was one of the early hypothesis about the spread of AIDS way back when. It must happen often enough that researchers gave it some smidge of consideration.
People like you are so fucking obviously stupid. Being ignorant is OK, but stupidity is posting as if you knew anything.
Why in Sam Hill didn't you just Google before posting bullshit?
It little behooves the best of us to comment on the rest of us.
So rich nations do more about problems that affect their own people than poor nations do, or problems that don't affect their own people?
Yeah, I think you've just put the finger on something real big here.
By the way GSK, the company working on this vaccine, is European.
Nice conspiracy theory, except if you do some research you will realize that they aren't just NOW doing. If you look into the companies involved in these treatments/vaccines, you can find data and press releases indicating they've been working on these for years. For example, the cure that was used on the 2 doctors a few months ago has been known about for years. They were doing animal trials a few year back, and they said then that they were hoping to be able to get approval for human subjects a few years from then. They never got that far, but then those 2 doctors got infected, so they made an exception and allowed an experimental, untested-on-human medication to be used on them.
You might ask why they made an exception for these doctors NOW while other have been dying all along and they didn't care. Well, how would you feel if they allowed an untested, experimental medication to be used on some poor, sick, black African people? I'm sure the media would have a field day with that one.
One problem with rushing a treatment to market (aside from the obvious side effects and toxicity risks) is that you sometimes end up with a treatment that works but you have no idea why it works. This has happened with some drugs in the past. We've started testing them and found that they worked really well. So we stopped the clinical trials early in order to rush the drug to market quickly for perfectly appropriate humanitarian reasons. After all if you have a drug that you know works then it's pretty cruel to withhold it from someone who would benefit. The problem is that sometimes we know a drug works before we know why or how it works.
Part of clinical trials is figuring out if a treatment will work. The other part which is sometimes even more important is figuring out why a treatment works so that we can build off that information in the future. If you skip or stop clinical trials early you sometimes end up losing this critical information. If we don't know why something works it's pretty hard to make further progress in developing even better treatments.
Coincidence, maybe, but the fact that the vaccine was ready *almost as soon* as the first american was infected proves that the vaccine was in development for a *long time* before that happened.
What? Do people actually believe the TV shows they watch? Vaccines don't actually get developed over night.
Development of the vaccine has been vastly accelerated already, due to the virus's spread and its mortality rate. No, development of the vaccine has been vastly accelerated already, due to WHITE PEOPLE GETTING SICK. When Ebola was only killing poor black people in Africa, no one gave a fuck. Now that rich white people are getting it, we'll have a vaccine within the year.
i find it amusing that no other countries are working for a vaccine or treatment for this virus... or is it that only the US researchers have this ability?
When death is on the line people will do what they need to do to survive, your study be damned.
They'll do what they THINK will help even if there is no evidence to back that up. Just because desperate people are being (understandably) irrational doesn't mean the rest of us should join them. We do things the way we do them because it works and because the alternatives result in much worse problems.
So just give the drug to them all and save your study work for when there isn't an epidemic going on.
There is always an epidemic going on somewhere. The value of these studies is that it saves many at the expense of a few. That is the cold hard fact of medicine. Some people are going to die/suffer so that others can live. Giving someone a treatment before we actually have proof does a disservice to later patients because we cannot learn what works and why. It also is right on the edge of being quackery. The vast majority of candidate treatments turn out to be ineffective or even outright harmful. There are sometimes good reasons to make exceptions to this policy but they are relatively few and far between.
Start gathering data on the front line ebola care-givers who are doing so right now, and then when the vaccine is ready, if all front line ebola caregivers choose to receive it, compare the data from before the vaccine to the data after the vaccine.
Of course, if the experimental vaccine is effective, then we should be keeping people from dying and we don't need a control group. But this is an unwarranted assumption: we don't know yet if the exerimental vaccine is effective -- this is what we are trying to determine, and we won't have the answer until after the experiment.
You say "we already know the death rate of ebola through empirical observation", but the death rate depends on many variables. For example, health-care workers probably have better habits than the average person, but they are exposed to Ebola more than the average person. Suppose after the vaccine we see a lower death rate. Are we sure this is due to the vaccine? Perhaps the workers who got the vaccine were from volunteers from Sweden, and Swedish people are more resistant to Ebola? The point of randomized trials is exactly to account for any known and unknown effects of this type by randomly choosing who gets the treatment and who doesn't among a reasonably uniform population. This way the people who get and don't get the treatment differ statistically only in the experimentally tested property, and we can have some confidence any observed effects are due to the treatment.
The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.
I disagree strongly with your framing of this issue. The objective is (or should be) to keep the LARGEST POSSIBLE number of people from dying. This means that we have to weigh the needs of the patients who are sick right now against the needs of future patients who will become infected. The demonstrated best way to learn if a treatment is effective, safe and to learn why is through controlled studies. Often this means we sacrifice some so that more may live in the future. While i'm not suggesting we don't do what we can for every patient it would be borderline suicidal to ignore proven best practices to save some now that will result in more deaths down the road.
Without a control group you might learn if a treatment is effective if the effect is sufficiently pronounced but you'll have little idea why. To understand why a treatment works you need to be able to control the variables between groups getting a treatment and those that are not and isolate those things that are different between them. A treatment that saves a patient today is much less valuable than one that saves hundreds tomorrow.
The solution to this is easy, it's just ones America's puritan's can't swallow. You send over terminally ill volunteers who have a short time to live anyways. You use them as the non-vaccinated group. If they contract Ebola, you allow them an assisted death (OH THE HORROR/THINK OF BABY JESUS). Everyone wins.
Either they ate animal meat that wasn't cooked properly or they went there primarily to have sex with people or animals who knows.
Yes, because those are the ONLY two ways that people come in contact with fluids from animals. Thank God butchering is such a tidy process, animals don't bleed after you shoot them while on the hunt, and that people handling animals never get bitten, because if any of those were things that actually happened we might need to consider the possibility that there are other ways people could get infected, and we wouldn't want to do that!
You can always do that research in the future.
So lives in the future are worth less than lives now? I could not disagree more. If we practiced what you suggest we would never do any studies because we would always be putting them off into the future. We use controlled studies because it is the best way to know if something works and just as importantly why it works. And yes this comes at the cost of some lives. We sacrifice some so that more may live in the future. If you can find a better way to do it then let us know and go collect your Nobel prize. Without controlled studies it is nearly impossible to figure out whether a treatment is effective or not.
Rushing a life-saving treatment to deployment is always ethical:
Not true. First off, we DO NOT KNOW if these treatments will work. Even if they do work we will not know why they worked. We might get lucky but odds are we will not. Giving an unproven treatment in the hope that it will work outside of a medical study is compassionate but ultimately self defeating because you learn nothing from it. If defy you to find a medical ethicist who would agree that rushing unproven candidate treatments into use is "always ethical". I assure you that they would say exactly the opposite.
people like to bitch about experimentation on humans and all the complications and side-effects and suffering you can cause, but this doesn't fucking apply when your human guinnea pigs are definitely going to die soon.
Riddle me this. You apply an unproven candidate treatment to a patient dying of ebola without that patient being part of a controlled study. How do you know whether or not the treatment worked? The answer is you don't. You literally have no way to know if the treatment is what saved that specific patient or if some unknown factor saved them. Not everyone who has ebola dies from it. So instead of taking the risk of the patient dying and learning something you have administered a treatment and learned absolutely nothing in the process. You don't know what saved that patient and in the process you have denied future patients the benefits of what could have been learned. THAT my friend is hugely unethical. There are damn good reasons why we do not do things that way.
There are some exceptions we make on occasion for compassionate reasons. We try an unproven treatment as a last ditch effort to save someone certain to die when nothing further can be learned. But patients infected with ebola do not fit that description. Many/most will die but not all. Forgoing the opportunity to learn something from their disease process in favor of quackery is highly unethical.
Thomas Eric Duncan has died of Ebola
Oddly enough, this is perfectly timed with someone in the US getting infected.
Not hardly, we're still some number away before that happens.
What vaccine? There is no vaccine? All we have is antiviral drugs that are effectively antibody supplements. In previous outbreaks, people have been cured by receiving blood (and antibodies) from someone who has already successfully fought off the infection. The drugs are basically just an artificially manufactured form of that. You don't run large volume production of an experimental drug for a virus that only has small outbreaks every few years.
Today...
There are two types of people in the world: Those who crave closure
More like US news covers US researchers.
There are two types of people in the world: Those who crave closure
The first vaccine to be used was developed in Canada.
This Ebola epidemic seems more like a marketing ploy where n+1 pharmaceutical companies are attempting to create a need for their fancy-schmancy snake oil. I remember from “back in the day”, reading that Ebola had a 100% mortality rate; once you’re infected, you’re as good as dead.
Well said. You also want to know if your vaccine causes a recipient to contract rapid onset brain cancer, or some other side effect that might be just as bad as the thing that you are trying to prevent/cure in the first place before you administer it to everyone. The Hippocratic oath contains a line about 'Do no harm'.
HA! I just wasted some of your bandwidth with a frivolous sig!
Vaccine trials first started in 2003. The current best candidate was first tried in a human in 2009 in Germany.
Was wondering if I'd see that linked here.
The Onion really hit the nail on the head sometimes.
Famine, plague, war, or birth control. Choose. I guess you have.
-Malthus.
Too late. Game over.
The West will begin mining the harbors and cratering the airports so
nothing can leave. They will landmine the jungle. Anything that leaves
is sunk or shot. Snipers sans Frontieres. Quarantine with extreme
prejudice.
Civilization is a choice. Make it. Soon.
Or don't, and the population goes back to the under-billion level
before the West started feeding everyone... No more global warming
or traffic problems!
it has to be done this way.
Keep using your protocols, make the research a top priority.
The Kruger Dunning explains most post on
This is not "only now coming to light"; it's just that you couldn't be bothered to read about it until it was spelled out in a Slashdot headline. People didn't start working on this last week. I'm not sure how fast you think medical research works.
Well, none of the current or the older vaccines have been proven to work. Impossible.
The idea to produce vaccines the way they do it, is rather, lets say, .... questionable to say the least. Usually, they (who damn well know the vaccine doesn't work) introduce it once the outbreak has already peaked.
Try me and find out when polio hit hard and when did the vaccine come out.
The only reason anyone in the US was infected was because someone from Africa foolishly thought they would get better healthcare by hopping a plane to come here (they died today or yesterday). The proper solution to this would be to close the borders and quarantine the continent - nobody will even notice a hit trade-wise.
If it works...yaay no more racism. And if it doesn't, well the US is a racist country.
Funny that ebola has been in existence in the modern world since the 70s, yet only now this is coming to light. Oddly enough, this is perfectly timed with someone in the US getting infected.
"Shit, this is on OUR turf now!??! Better do something about it!"
There is a causal relation driving this correlation, but it's not the one you cynically postulate. Both the appearance of someone in the US with the disease and the attempt to create a vaccine have been caused by the scale of the latest outbreak.
All these snarky comments do highlight a point though (which I am sure will offend many): Why should any non-African nation even have to do anything-Ebola related ever?
The African countries have had 38 years to develop a vaccine, quarantine procedures, public education, and adequate medical infrastructure to handle an Ebola outbreak, but have not done so.
Now the rest of the world has to dig in to shut down this outbreak and work up a vaccine because Africa as a continent has shit away the majority of the last four decades on infighting, gang warfare and corruption.
spread by the CIA into the united states
abolish the CIA
Funny that ebola has been in existence in the modern world since the 70s, yet only now this is coming to light. Oddly enough, this is perfectly timed with someone in the US getting infected.
"Shit, this is on OUR turf now!??! Better do something about it!"
Ignorant troll. The USA (and usually Europe as well) has long devoted resources to treating and/or eradicating tropical diseases that are not any kind of threat to the USA.
Study the funding sources and efforts to eradicate Guinea worm (dracunculiasis) and lymphatic filariasis
Also for may decades the USA was the only country with a significant investement in malaria research.
Tell me how Africa can lure away researchers from the top universities? How can Africa build their own universities with the facilities capable of advanced medical research? Because of their abysmal currency exchange rates, it costs your typical African close to $1,000,000 (equivalent) to buy a commercial-grade tractor and ship it from Europe. You think they can afford to build top of the line laboratories? Tyrants can barely feed their "friends" with those exchange rates.
Infighting, gang warfare, and corruption easily spread because it's easier to kill your neighbor for his tractor than it is to work your hands to the bone for 20 years to buy one. When you killed your neighbor, you don't have 20 years of farming experience to run a tractor, so your "farm" is going to churn out garbage yields. Europe doesn't care that you killed your neighbor because either he was white (and rich enough to buy a tractor) or his crops were purchased only by whites. African is for the blacks, you see. You were just being Robin Hood, taking from the rich and giving to your poor... and your neighbor was probably going to kill you anyway, maybe.
This post may sound jilted, but it contains everything you need to know about the last 100 years of Africa.
The opposite possibility is also an issue.
The Vaccine could be 0% effective but other best practices for handling infected patients rolled out around the same time are 90% effective.
It would be difficult to distinguish between that and the Vaccine being 90% effective.
The main difference is that Ebola has a mortality rate close to 90%, whereas all those others have something like .1% mortality rates.
----------------------------------- My Other Sig Is Hilarious -----------------------------------
Canada and Britain are not part of the U.S.
Hope that helps.
The entire article is about a vaccine.
Duh. There are vaccines *and* experimental drugs.
But this is slashdot. I guess nobody reads jack before they post because their mental models of the world appear to be "good enough" to reason with (rolls eyes).
No. The article is about how to do testing of a hypothetical vaccine that has not yet been developed.
There is no vaccine. The article is merely expecting that vaccines will be ready for testing several months, and is questioning how the testing of those vaccines should take place when available.
Maybe I spoke to soon.......
Parent probably isn't trolling, but referencing the Onion headline.
my, your, his/her/its, our, your, their
I'm, you're, he's/she's/it's, we're, you're, they're
The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.
What's the death rate through empirical observation?
Sure, it is tough, but without the control group all scientific basis for efficiency evaluation goes out the window. That leads to guesswork that routinely kills a lot more people later. That said, of course the control group should be as small as possible as it can be and still give scientifically sound results. It might also be a good idea to give the members or the control group preferential treatment when they get infected to offset the higher risk they are running. But there is no way to get around this requirement. It is essential and critical to the much-needed optimization of the vaccine, not only for improving effectiveness, but also for decreasing unintended side-effects. And for something like Ebola, these side-effects may well include death. Especially in that case a clear and accurate estimation of its benefits are needed.
There have been enough screw-ups with Ebola already. Let us not add a botched vaccine trial to the list.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
That article cites a vaccine from GlaxoSmithKline that started human trials on September 2nd, and also mentioned the Public Health Agency of Canada vaccine. These aren't hypothetical. They are untested, but not hypothetical.
I admit, I did not read that far down. The first few paragraphs mention the GSK program to develop one, but was only speaking in generalities about vaccines.
What about the deputy sheriff in Texas? Who apparently didn't do anything more dangerous than entering an infected man's house without protective gear?
It was just a scare because he was feeling a bit ill, he did not contract Ebola and has been cleared.
Yes there are always vaccines for everything "in development" this is called research.
The opportunity of making a news story at just the moment someone in the US was confirmed as having the strain, is more a marketing ploy to ensure the company with the goods is getting attention and their phone ringing. Better to have your phone ringing offering you government money than your competitors phone ringing because some government official happens to know someone in that industry.
Is the vaccine production ready for the general population, hell no!
Did I tell you I have a perpetual energy machine that is "in development" ?
I'm not aware of any evidence of a particular mutation that has been identified leading to this putative increase in incubation period. The observed differences in incubation rates estimated for this outbreak are not different enough to point to a different incubation period, when you take into account that the statistics being collected are sample statistics, not population statistics. Not everyone who dies is know to the authorities, and often there is significant uncertainty about the actual date of infection.
If you know of any new data (mine is about 3 weeks old), please post a link.
Ever since the first identification of Ebola, the potential of it to expand like this has been recognised. Most previous outbreaks have been in relatively isolated areas (Kikwit, 1995, being an exception), simplifying prevention of spread. However, West Africa has generally higher population densities, and the disease is simply spreading between villages and hamlets.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Because diseases don't respect borders, and people move around.
I live in Britain ; next month I'm likely to be working in Canada ; last month I was working in West Africa. There are approximately 80 Americans working on the same vessel as me, commuting month-by-month to the USA.
The world is bigger than the borders of your mind. If you find that inconvenient, that's tough on you.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Got it now? Just because your only idea of life is about fucking sheep or boys doesn't mean that there aren't transmission routes beyond your tiny imagination.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"