Ebola; Epidemic, Pandemic, or Fear Mongering. Actual Rates of Transmission.

a reply to: TinkerHaus

Respectfully, you are incorrect about a virus never changing modes of transmission. Ebola Reston went airborne in 1989. By sheer chance, that same mutation caused it to be asymptomatic in humans.

a reply to: cuckooold

If you saw that gizmodo article and you've read through the comments, then you've possibly seen my post.

The article is specifically about Ebola's R0 so, to add to what the article says:

Epidemiological modelling based on the data from previous EBOV outbreaks has produced a basic reproduction number (R0) of 2.7 with a 95% confidence range of 1.9 to 4.1 (Legrand et al., 2007). This R0 is comparable to influenza (Mills et al., 2004) and would seem to be comfortably within the range required to generate an EVD pandemic. In answer to the question of why this has not already occurred in human history, perhaps the most persuasive response is that EVD very fortunately only emerged into human populations around the time of its discovery in the mid-1970s (Walsh et al., 2005), by which time we were fairly equipped to deal with it in remote low population density settings. Whether we can contain it within a large city, should the necessity to do so arise, remains to be seen.

The 2014 Ebola virus disease outbreak in west Africa

Infectious dose:

Flu: 100-1000
Measles: 100-12500
Ebola: 1-10

This is the number of virus particles it takes to infect someone.

Add in the demonstrable dangers of indirect contact transmission, and I do not think it is foolish to give this disease the ultimate level of respect.

Anything less is cuddle mongering.

a reply to: boncho

I understand your point, but I still must point to the fact that we've never once witnessed a virus changing it's transmission method. At the link I provided earlier, the virologist states that multiple amino acids need to change for this to happen - and we've yet to witness it happening naturally.

To date, the idea of a virus "going airborne" is not a reality. At least not in nature.

If you want to talk about some evil bastards engineering Ebola to easily transmit through the air; that is a discussion I'd be interested in having, although this thread is probably not the place for it.

So many steps have to happen so precisely for this mutation to occur - it's something we've yet to see take place naturally. I'm by no means saying it's impossible - just that there is no precedent at this point to base these fears upon.

originally posted by: netwarrior
a reply to: TinkerHaus

Respectfully, you are incorrect about a virus never changing modes of transmission. Ebola Reston went airborne in 1989. By sheer chance, that same mutation caused it to be asymptomatic in humans.

Reston was not airborne, though it has been speculated. Studies failed to prove that it had in fact gone airborne.

Reston was also an animal strain that did not infect humans.

ETA: Finally found the article:

Link

Pigs seem to give off more aerosolized viral particles than other species, says Derek Gatherer, a viral evolutionary biologist at Lancaster University in England. “If it’s going to spread by aerosols, then pigs are the species to do it,” he says.

But he doesn’t think the researchers definitively demonstrated airborne transmission of the Ebola virus. Virus-laden droplets of water could have splashed from the pig pen to the macaque cages when the researchers washed the pig enclosure, he says.

Pigs probably aren’t a source of Ebola outbreaks. Few have even been found to carry Ebola. Pigs in the Philippines have been found to carry Reston ebolavirus, a species of Ebola that does not cause disease in people. No African pigs are known to be infected with Zaire ebolavirus, the cause of the current epidemic.

Even if pigs can transmit the virus by air, they may be unique in the ability. The new study, published July 25 in Scientific Reports by Kobinger and a different group of collaborators, found no evidence that sick macaques could give the virus to healthy monkeys through airborne particles.

Fabian Leendertz, an epidemiologist and disease ecologist at the Robert Koch Institute in Berlin, says that the outbreak is spreading by human-to-human contact. The people who are dying are mostly women who care for the sick, their children and people who touch dead bodies during funeral rituals, he says. Health care workers are also at risk.

But Ebola is not nearly as easily transmitted as many people assume, he says. Even if an infected person were to hop on a plane and fly to the United States, Europe, or elsewhere, Leendertz says, tight health care measures would ensure that Ebola “will never get far.”

We miss the forest for the tree.
Ebola requires its animal reservoir, which appears to be fruit bats endemic to the West African region.
I am therefore not concerned with Ebola.
I am concerned with the likelihood of an Influenza pandemic. It has occurred before, will likely re-occur, and can be potentially devastating to the Western world.

In the grand scheme of things, Ebola is hyped for nothing. People not taking their Influenza vaccines is more worrying, since it decreases herd immunity to a more serious pathogen.

a reply to: TinkerHaus

I understand your point, but I still must point to the fact that we've never once witnessed a virus changing it's transmission method. At the link I provided earlier, the virologist states that multiple amino acids need to change for this to happen - and we've yet to witness it happening naturally.

To date, the idea of a virus "going airborne" is not a reality. At least not in nature.

What are you talking about? Yes we have. Not all viruses are able to be monitored from the origin to proliferation and some die out before even having a chance for a good epidemiological study, but yes, just about every virus that is airborne started out some other way. (Besides very old ones, genetical engineered, etc.)

Molecular Epidemiology and Brief History of Emerging Adenovirus 14—Associated Respiratory Disease in the United States

Background. First isolated in the Netherlands in 1955 during an outbreak of acute respiratory disease (ARD) among military recruits, human adenovirus 14 (HAdV-14) has historically been considered rare.With no precedent of circulation in North America, HAdV-14 has been isolated from military and civilian cases of ARD of variable severity since 2003 in the United States.

Methods. Ninety-nine isolates from military and civilian cases from different geographic locations and circulation periods were characterized by restriction enzyme analysis of viral DNA and select gene sequencing.

Results. All examined viruses were found to be identical and to belong to a new genome type designated “HAdV-14p1” (formerly known as “14a”). Comparative alignments of E1A, hexon, and fiber gene sequences with other subspecies B2 HAdVs suggest that HAdV-14p1, like the closely related HAdV-11a, arose from recombination among similar HAdV-11 and HAdV-14 ancestral strains. A deletion of 2 amino acids in the knob region of the fiber protein is the only identified unique characteristic of HAdV-14p1.

Conclusion. The current geographic distribution of HAdV-14p1 involves at least 15 states in the Unites States. The role of the fiber mutations in the recent emergence of HAdV-14p1 ARD in North America warrants further study.

Human adenoviruses (HAdVs) include 52 recognized serotypes assigned to 7 species (A–G) on the basis of biophysical, biochemical, and genetic criteria [1]. Species B includes 2 genetic clusters, subspecies B1 and B2. The serotypes of subspecies B1 (HAdV-3, HAdV-7, HAdV-16, HAdV-21, and HAdV-50) generally cause acute respiratory disease (ARD), whereas the serotypes of subspecies B2 (HAdV-11, HAdV-14, HAdV-34, and HAdV-35) are more often associated with urinary tract infections and opportunistic infections of immunocompromised hosts [2].

jid.oxfordjournals.org...

More on adeno-14

As an example, consider a unique ecological challenge faced by many pathogens: appropriate habitats can be few and alarmingly far between. Put yourself in the position of a virus in its natural habitat — a human host. You've infected some cells and managed to reproduce, but the host's immune system is onto you now and is turning up the heat. This environment is no longer so hospitable. How can you get your descendents to a friendlier habitat (i.e., a new, unexploited human body)? Without legs, wings, fins, or any of the usual means of locomotion, your descendents' prospects for reaching a new host under their own power are nil. However, natural selection has provided pathogens with a number of sneaky strategies for making the leap to a new host, including:

Droplet transmission — for example, being passed along when one host accidentally sneezes on another. The flu is transmitted this way.
Airborne transmission — for example, being exhaled by one host and inhaled by another. Tuberculosis is transmitted this way.
Vector transmission — getting picked up by a carrier (the vector — e.g., a mosquito) and carried to a new host. Malaria is transmitted this way.
Waterborne transmission — leaving one host (e.g., in feces), infecting the water supply, and being taken up (e.g., in drinking water) by a new host. Cholera is transmitted this way.
Sit-and-wait transmission — being able to live outside a host for long periods of time until coming into contact with a new host. Smallpox can survive for years outside of a host!
Pathogen lineages that fail to meet this challenge and never infect a new host are doomed. They will go extinct when their human host dies or when the immune system destroys the infection.

]

I like the view of the gentleman who discovered Ebola in 1976. He, like others in the forum all agree that any outbreaks in the US will be short lived. I agree with that to a point, as I think here are certain ways there could be breakouts, but only under very articular conditions.

But he raises a much more obvious danger:

Do you think we might be facing the beginnings of a pandemic?

There will certainly be Ebola patients from Africa who come to us in the hopes of receiving treatment. And they might even infect a few people here who may then die. But an outbreak in Europe or North America would quickly be brought under control. I am more worried about the many people from India who work in trade or industry in west Africa. It would only take one of them to become infected, travel to India to visit relatives during the virus's incubation period, and then, once he becomes sick, go to a public hospital there. Doctors and nurses in India, too, often don't wear protective gloves. They would immediately become infected and spread the virus.

If it reaches India there is such a gross disparity among rich/poor because of the caste system that ghettos, and as he says, doctors will be infected, which could cause a nationwide problem that would be devastating. Because of how many wealthy East Indian people there are, there is a lot of travel between India and North America. (Not to mention the world).

He does not however, think that the virus will change much or go airborne. I concede that there isn't anything so far to support a wide spread panic about it going airborne.

The virus is continually changing its genetic makeup. The more people who become infected, the greater the chance becomes that it will mutate ...

... which might speed its spread. Yes, that really is the apocalyptic scenario. Humans are actually just an accidental host for the virus, and not a good one. From the perspective of a virus, it isn't desirable for its host, within which the pathogen hopes to multiply, to die so quickly. It would be much better for the virus to allow us to stay alive longer.

Could the virus suddenly change itself such that it could be spread through the air?

Like measles, you mean? Luckily that is extremely unlikely. But a mutation that would allow Ebola patients to live a couple of weeks longer is certainly possible and would be advantageous for the virus. But that would allow Ebola patients to infect many, many more people than is currently the case.

But that is just speculation, isn't it?

Certainly. But it is just one of many possible ways the virus could change to spread itself more easily. And it is clear that the virus is mutating.

www.theguardian.com...

a reply to: boncho

OK - so give me an example of a virus that "went airborne."

www.scientificamerican.com...

scienceblogs.com...

www.columbia.edu...

So, says Dr. Levine, "The media's claim is not totally without scientific basis. But there are no precedents for it, and it's unlikely.

"I think it's irresponsible to raise that concern," she added, "because in general viruses are very well-adapted to their milieu­­and they don't just suddenly change their environment." Will this kind of level-headed assessment quell media hysteria? Stay tuned.

EVERY. SINGLE. VIROLOGIST. says that there is no precedent for what you people are claiming. You've still yet to show an example of a virus mutating in such a perfect way that it can now be transmitted through the air, where it couldn't before. Some viruses are robust, and able to do so, others are not. We do see mutation in viruses, but we've never witnessed a virus that is transmitted by bodily fluids all of a sudden becoming airborne.

Jeeze, we are SCREWED when HIV "goes airborne."

Here is an inconclusive study on Ebola transmission:

When news broke that the Ebola virus had resurfaced in Uganda, investigators in Canada were making headlines of their own with research indicating the deadly virus may spread between species, through the air.

The team, comprised of researchers from the National Centre for Foreign Animal Disease, the University of Manitoba, and the Public Health Agency of Canada, observed transmission of Ebola from pigs to monkeys. They first inoculated a number of piglets with the Zaire strain of the Ebola virus. Ebola-Zaire is the deadliest strain, with mortality rates up to 90 percent. The piglets were then placed in a room with four cynomolgus macaques, a species of monkey commonly used in laboratories. The animals were separated by wire cages to prevent direct contact between the species.

Within a few days, the inoculated piglets showed clinical signs of infection indicative of Ebola infection. In pigs, Ebola generally causes respiratory illness and increased temperature. Nine days after infection, all piglets appeared to have recovered from the disease.

Within eight days of exposure, two of the four monkeys showed signs of Ebola infection. Four days later, the remaining two monkeys were sick too. It is possible that the first two monkeys infected the other two, but transmission between non-human primates has never before been observed in a lab setting.

While the study provided evidence that transmission of Ebola between species is possible, researchers still cannot say for certain how that transmission actually occurred. There are three likely candidates for the route of transmission: airborne, droplet, or fomites.

- See more at: healthmap.org...

Droplet or aerosol transmission is not quite as bad as airborne but it still can mean a huge difference in numbers of infected. Especially among healthcare workers.

a reply to: boncho

Right - the people most at risk are those within 3' of an infected patient. In many cases you could touch or even cuddle with an infected person and come away fine. I'm by no means recommending this, just saying it's not as easy to contract as a lot of people are making it out to be.

I'm by no means trying to downplay the situation either - it is very serious and there is reason for concern. It never helps to be overly prepared for ANY situation. I'm simply saying we all need to take a deep breath (not within 3' of an Ebola-infected person) and think critically about it. As I mentioned earlier, Enterovirus D68 is a much more dangerous and possible problem, and the media is all but ignoring it (and so are we, as a result) in favor of this Ebola outbreak.

a reply to: TinkerHaus

Woah woah, woah. You are totally moving goalposts here. You said earlier "Can you give any examples of viruses that humanity has ever witnessed "going airborne?" and then you post links on this specific strain of Ebola from virologists that said they haven't seen it go airborne.

That is way off base. I have posted a bunch of sources now, to show the same viruses from the same family with different transmission routes. Adenovirus type 14 as a uti, living predominantly in a woman's urinary tract, and then going to contact and to airborne.

Besides that, if you speak with any people in the field, beyond the media, they will tell you that no one has really touched ebola since a few brave souls did in the 60s. It is one of the deadliest viral agents that we have next to no data on, because no one has touched it for eons, either blaming no reason (low prevalence) or because it is insanely expensive and dangerous to handle.

That is why we have no measures to fight it.

Most never expected it to reoccur with any impact.

OP and others, you are wrong.

1: This Virus can live on surfaces for 50 days at 37 F, Africa does NOT have those temperatures, we are introducing a normally non threatening entity into a new environment.

2: American cities experience these temperatures 6 months of the year or more in many locations in which a dollar bill can pass through 100 hands in a day, unheated subway trains and shopping carts are kept outside

3: We are coming to Flu season with Entero Virus loose and the combination of sneezing and coughing can be deadly alone give the temperature range

4: We do have an Animal vector, our cities are filled with Rats and there are 64 Million Rats in NYC alone, a Bat is nothing more than a Rat with wings... it is entirely "possible" that Rats can become a serious fast spreading vector.

I am not saying this is GOING to happen

But i'd be very, very concerned of a Liberian dying in an unheated apartment in the Bronx and the Rats feeding off him for a couple of days, or riding an unheated subway car through the city used by 30,000 people a day in January or any some such scenario.

Because if you start getting 10's of thousands of cases in NYC and people flee into the rest of the country in winter, Millions CAN die....

The Virus (and I have a microbiology degree btw) doesn't operate by killing it's host species there is always balance, OUR way of life is different, our farming and social system is very different than Africas, Pandemics happen when a Virus gets introduced into conditions where it can suddenly do things it couldn't in it's natural environment...

and we have those conditions, our massive transportation system and cold weather is just one... we also keep pigs by the 10's of thousands in disgusting conditions and close proximity to each other, there is the "immune system" question in regards to GMO use, there is "Flu season" as a natural aerosol agent, we mainly work in buildings with "central air" under these conditions, we mass load people through subways, we have no idea what animals might vector on this continent, one might find the common sparrow is an awesome air delivery system...

Our conditions are VERY different, we should make no assumption as to what this Virus can and can not do under these conditions.

a reply to: boncho

What? I don't think you're reading the material..

They aren't specifically talking about Ebola, so far as precedent for transmission goes. They are talking about a precedent in all known and studied viruses.

From one of the many links I provided:

In fact, there’s almost no historical precedent for any virus to change its basic mode of transmission so radically.

originally posted by: cuckooold
a reply to: boncho

I'm not downplaying it, but rather addressing the question, is there too much fear mongering? I've read threads from people saying we should ban vey flight from Africa, while others believe it's some form of global population control from the illuminati, shadow government, or some other hidden entity.

I do think that, if our measures have been found to fail to keep unidentified infected individuals out of the US, that we should consider restricting flights from infected areas. Duncan is just such a case. CDC identified how many potential contacts--wasn't it 80-100? I'm not panicked about Ebola reigning unchecked within the US throughout the population. I'm concerned that 80-100 people had to worry about whether they've been infected with Ebola--an illness with a mortality rate of around 60%--because of one man from Liberia. According to the CDC, courtesy of Discovery, 50 people are still being monitored for having contact with Duncan except for one guy.

A homeless man.

news.discovery.com...

Give me one good reason why we haven't restricted flights from these areas. An actual good reason and not an homage to the almighty dollar.

a reply to: cuckooold

originally posted by: ZiggyMojo
I think the rate at which Ebola infects is dependent so far on geography and the population density.

I agree. Another factor is who is getting infected and their ability to spread it. The volume of people exposed by infected health care workers/contaminated facilities could far exceed normal transmission rates within a community.

I'm afraid were venturing into uncharted waters. We need stats concerning transmission rates from medical staff/facilities in west Africa. Common sense tells me those numbers are higher. We won't have an accurate assessment if medical staff/contaminated facilities are left out of the equation. Locals are already suspicious of medical workers/clinics and probably for good reason.

a reply to: Morningglory

Like the infected nurse who was treating a missionary in Madrid?

A Spanish nurse has become the first person to be infected with Ebola outside of West Africa after contracting the virus while treating a missionary who died in a Madrid hospital, Spain’s health ministry said Monday.

www.nytimes.com...

Not a whole lot of information about whether she was diagnosed while still asymptomatic or if she developed symptoms and then, it was detected. However, the short article states this:

Ana Mato, Spain’s health minister, told a televised news conference that the nurse tested positive for Ebola twice, and that the rest of the 30-person team that looked after the missionary were undergoing medical tests to determine whether they had contracted Ebola.

I'm guessing, considering that the rest of the health care team of the missionary now undergoing tests means that she became symptomatic and was tested and not tested as a precaution. Could be wrong though in that assumption as it is an assumption.

a reply to: cuckooold

Complete fear mongering OP.

a reply to: cuckooold

What is going to happen if this virus mutates with the seasonal flu? That's something we need to look out for IMO.

a reply to: criticalhit

Nail on the head. Nice post sir.

a reply to: TinkerHaus

Sorry, I have to retract my previous position. I was under the impression that we have seen viruses change their transmission routes. Especially since they have left animal population (which are transmitted one way) and move on to humans, which seems to be transmitted another way.

I am not sure how this is explained as if its considered a different virus or what. But I am not one to argue a moot point, or refuse to admit Im wrong. Thanks for teaching me something new today...

I also do not know how to reconcile the environmental factors of an aerosol transmission, since if the given environment facilitated the virus, it seems it would live long enough to transmit through aerosol?

When it comes to viruses, it is always difficult to predict what they can or cannot do. It is instructive, however, to see what viruses have done in the past, and use that information to guide our thinking. Therefore we can ask: has any human virus ever changed its mode of transmission?

The answer is no. We have been studying viruses for over 100 years, and we’ve never seen a human virus change the way it is transmitted.

www.virology.ws...