Morbo says: VIRUS TESTING DOES NOT WORK THAT WAY

In the ridiculous apologetics activists and their supporters use to explain why they are right in claiming ISA virus is in BC, one particularly odious claim keeps popping up.

This screed from Twyla Roscovich, Alexandra Morton’s new fiction writer and propagandist, lays out the claim:

Nearly every lab that doesn’t have direct ties with industry and the government seems to be able to find at least segments of the virus, while every lab that has a vested interest in not finding the virus can’t seem to detect it. It’s easy not to find this virus if you don’t want to.

Sorry, but this is bullshit. And like true propaganda, Twyla and Morton are banking on the hopes that you, dear readers, are not well-versed enough in science for your bullshitometers to be going off the charts whenever they talk.

We think you’re smart enough to think for yourselves, and do a little research, which shows that CFIA’s lab has found ISA virus 10 times already this year. Clearly CFIA has no problems testing for this virus, finding the virus and verifying suspected findings of the virus. If the lab can find the virus in Eastern Canada, there’s no reason why it couldn’t find it in BC.

But wait, they’ve got an explanation for that too. It’s some convoluted conspiracy theory about protecting trade. Which is stupid, because the East Coast salmon farming industry is almost as big as BC; the East Coast industry is ISA-positive; and the East Coast industry has no problems selling fish to the USA. And let’s not forget that ISA virus poses an even greater threat to wild salmon stocks on the East Coast than it ever would here, because wild Atlantic stocks on the East Coast have been so badly overfished they are endangered.

Showing their ignorance

Beyond conspiracy theories, Twyla attempts to peddle Morton’s weak scientific explanation.

In order for the CFIA to officially “confirm” ISA in B.C., it requires a high standard of proof called “virus isolation”. This means catching the virus alive and culturing it in a petri dish.

MorboVirus

No. That’s not how it works. You cannot culture a virus. If a lab gets a positive result in the initial virus test, what they do to confirm it is put the suspected virus in a cell culture. If the virus kills the cells, then you’ve got something. Alternatively, the lab can try and see if they can detect the entire sequence of the suspected virus to see if it actually is the one they think it is.

This is the same standard every lab testing for ISA in the world follows to confirm whether or not the virus is actually present. It’s called responsible science.

Twyla continues with a false statement.

The only way this requirement of proof has ever been fulfilled is during an active disease outbreak on a farm where the fresh sample of a dying Atlantic salmon could be rushed to a lab very quickly. It has never been successful with wild fish anywhere in the world.

False, false, false. Learn to Google, Twyla. While it is difficult to find wild fish infected with ISA virus, because a fish that gets sick would likely die and disappear, it has been done. In this study, 142 sea trout and wild Atlantic salmon were collected over four years from five Norwegian rivers and one fjord, and tested for ISA. The rate of infection ranged from 13 to 100 per cent, depending on the year and collection river.

The study shows that there is very likely a natural reservoir of ISA virus in the ocean, since there were no active farms near the collection rivers during several years of sampling.

As well, the study makes a most interesting statement:

“None of the fish showed any clinical signs of ISA.”

That’s right. None of the ISA virus-positive wild fish collected were sick with the ISA disease.

That doesn’t mean wild fish don’t get sick and die from this virus. But it does mean that wild fish can carry this virus without getting sick. Which takes a lot away from the hysterical apocalypse Twyla and Morton are trying to sell us.

Virus testing basics

Twyla continues with statements showing she and Morton understand nothing about virus testing.

If you use a PCR test that only reports an exact match as a “positive”, you could easily miss the virus, since even a slight change will make it “invisible” to a probe that is looking for an exact sequence. Kibenge’s lab was using a technique that was reading the sequences of the virus, rather than just using a probe that only reports an exact match of a very specific sequence. So he was able to pick up on viral sequences that contained slight variations of the virus, as well as fragments.

No. That’s not how it works. Kibenge’s lab is not more special than other labs testing for this virus. His testing methods and techniques were pretty much the same as everyone else’s.

PCR virus testing basically works by taking a probe (an artificially-created segment of RNA or DNA), running it over a sample and trying to get related segments of virus to “stick” to it. If you can make this happen, your sample might just contain the virus you’re looking for.

Different labs may use different probes, and may search for different segments of virus. But the entire point of PCR testing is that you look for sequences of virus that are specific to the virus. RNA sequences can be shared between different viruses. Looking for segments which are not specific to the virus you are looking for is pointless. “Slight variations” and “fragments” of the virus are meaningless, if you have no idea whether or not they are common to some of the trillions of other viruses out there that no one tests for.

As well, the testing machine runs cycles, replicating the material in the original sample, creating more and more of the virus RNA to “stick” to the probe. The more cycles you have to run to get a positive hit, the weaker the result. All of the test results Twyla and Morton claim as “positive” proof of the virus came after many cycles, and could not be replicated. None of the scientists who did the tests will claim these results are proof of anything, other than that perhaps they have detected something with similarities to the ISA virus.

Twyla makes a particular ridiculous claim, which appears elsewhere in Morton’s comments, which makes no sense to anyone who actually does PCR testing for a living.

The problem is with detecting ISA virus is as soon as a fish dies, the virus begins to “shatter”. Often only segments of the viral sequence can be detected by the time a sample gets shipped to a lab. Probes that the CFIA labs are using will only detect exact matches for certain sequences.

No. In poor-quality samples (such as all of the samples Morton has submitted for testing), the virus may have degraded in quality, but it’s not like it breaks into pieces and disappears. If a fish is truly infected with ISA virus, even in low levels, it’s highly unlikely that only the segments you are looking for will be undetectable. However, if you have a poor-quality sample (as all of Morton’s samples have been), the chances of the probe picking up degraded bits of the wrong segments of virus are higher, which results in false positives.

And again, ALL PCR probes work like that: they look for a match for a certain sequence of virus. That’s the whole point.

Follow-up is essential

Neanderthal or human? You’re not likely going to know just by sequencing the DNA, since human and Neanderthal DNA is 99.7 per cent identical. Follow-up tests and contextual information are critical.

Even if you get a positive in PCR testing, unless it is exceptionally strong, more testing is required to confirm it. For example, Neanderthals and modern humans have DNA that is 99.7 per cent identical. However, they are very different species. If you found a piece of old bone and tested it, and found that it was 99.7 per cent identical to Neanderthal DNA, you could not definitively state you had found evidence of a Neanderthal until you did more research. Where was the bone found? How old is it? Could it have been contaminated? Humans and Neanderthals have different bone structure, does this show evidence of those differences? Is there any supporting evidence near where the bone was found?

Science isn’t an easy-bake oven, as Twyla and Morton seem to think. You don’t just pop in your sample, and bing, out comes your fully-cooked proof of ISA virus. That’s why the follow-up tests, which they scorn, are so important.

“So why don’t you just give good quality samples to Morton to test, if you’ve got nothing to hide?”

We’re not the BCSFA and can’t speak for them. But why would we give our fish to people who have made it their life mission to shut down our farms? They have shown no scientific integrity. They have misrepresented the truth, been caught in lies, and shown they will say anything to advance their agendas.

If you’ve got a neighbour who complains constantly about your dog, even though the bylaw officer has investigated and found no problems, would you leave your dog with that neighbour while you go on vacation?

DFO takes thousands of samples from fish which die in pens each year and tests them for ISA. This has been done since 2003. None of these samples have ever shown evidence of ISA. But that’s not good enough for Twyla and Morton. That’s why they have to concoct ridiculous conspiracy theories to explain why no one but them can “find” the virus.

Let’s apply an ancient scientific principle here: Occam’s Razor. Since Twyla and Morton and their friends are the only ones claiming they have “found” ISA virus in BC, and since they have to resort to ludicrous explanations as to why, it is highly probable that they are simply wrong, but just can’t admit it.

Their apologetics, poor-quality data, lies, manipulation of data and conspiracy theories take them out of the realm of science and integrity. Believe their claims at your own risk.

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