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- So is Poliomyelitis the full name of Polio? Or is it a longer name? Because I know that there's a long "science-y" name for different things, like influenza for the flu, or TB for Tuberculosis. I'm almost positive that Poliomyelitis is the full name of Polio. If not, please correct me.(1 vote)
- How long after eradication would vaccines be required in order to prevent it (polio) from coming back?(1 vote)
- Diagnosis of Poliomyelitis is really based off of two things. So first of all you're going to want to think about what symptoms the patient is having. And the symptoms should paint a clear picture of polio, so it should be like oh, ok these are the symptoms, this should get you thinking about polio. To confirm the diagnosis, the next step you'll take a look at is the lab values, or specific lab tests I should say, that will determine that there is actually polio, or an active polio infection in the body. So first of all before we talk about the active polio infection, what are the symptoms we can see? Well the buzzword that you're going to encounter for polio is acute asymmetric, asymmetric, flaccid paralysis. So a patient is having an acute infection, it's a sudden onset. The patient, and usually we're thinking of a child. In fact, the term floppy baby is often associated with a polio diagnosis. Or really any other flaccid paralysis. So in polio, it's children less than six months old that are the most commonly affected. Really anybody can be affected, adults, children, but they are the most commonly affected. And they'll appear floppy because as you remember in polio, it's the motor neurons that are being affected. So you've got a motor neuron that innervates a muscle, so it provides energy to a muscle. And these motor neurons are damaged. And they may be damaged in an asymmetric pattern. So you might have this motor neuron getting shut down by the polio virus, but this other motor neuron, being completely active. So you'll see an asymmetric pattern. So we've got acute, sudden onset, asymmetric and flaccid so there's really no innervation to that muscle so the patient is weak. The baby is weak and appears flaccid, so you get this floppy baby syndrome. I'm not really great at drawing babies, so I just want you to picture in your mind's eye a baby that's just flopping on one side of the body, like their arm isn't able to move and that should alert you to this asymmetric paralysis. Now once these symptoms have been identified, lab tests should be underway. And there are actually several lab tests that you can really think about for this asymmetric paralysis. And all of them relate to the pathway that the virus, the polio virus, is going to take in the body. So the polio virus gets into the mouth, gets to the throat and can replicate here. It can also travel into the intestines, into the stomach and the intestines, and replicate in the small intestines. So it has two sites of replication. Then, the virus can actually spread to the spinal cord, to the central nervous system. So now there's three locations in which you can find the polio virus. So there are actually three lab tests that you can perform to diagnose polio. So one, let's go ahead and erase some of this here, and reveal this. You can isolate the virus from a throat culture. You can also isolate the virus from a stool culture. And the virus can also be isolated from the spinal fluid. So let me write that down, remember you can get a throat culture, you can get a stool culture, and you can get it from the cerebrospinal fluid, CSF. And this is usually done with a spinal tap, where the doctor inserts a needle into the spine, and withdraws some of this fluid that can be found. This fluid surrounds all of the central nervous system, it surrounds the brain, and it encoats the spinal nerve as well. So these are the lab tests, three different tests that can be performed. And any of them will work. The cerebrospinal fluid is the most accurate. If you can find the polio virus isolated in this fluid, that confirms diagnosis of Poliomyelitis, in fact, as a reminder, myelitis means inflammation in the spine. So right there, that shows, if you can isolate the virus, in this CSF, cerebrospinal fluid, then that confirms your diagnosis. But also because the virus can be shed through the mouth and in the feces, you can collect stool cultures or throat cultures as well. And stool cultures are one of the cheapest methods and fairly accurate, more accurate than throat cultures in determining if a person is infected by the polio virus. So stool cultures are fairly commonly used. Now once diagnosis is made, we need to progress to treatment. And unfortunately treatment is, well there is really no treatment for a person who has polio, it's really symptomatic support. If a patient, for example has their respiratory muscles, like the muscles like the diaphragm, if that is dysfunctional and they can't breathe, then they might need support through a breathing tube, put a breathing tube into the mouth to support the lungs. In fact in the old days, let's go ahead and scroll down while I show you this. In the old days, there was this thing called an iron lung. And here's a view of it right here, you can also see a patient sitting inside the iron lung in this picture. They have their head poking out, and this essentially allows pressure changes to expand the chest cavity and allow breathing. And this was before the time of having ventilators. And this has since been long retired, but it still provides you an idea of how serious the condition can be, and sometimes warrants respiratory support. Now though there is no treatment currently, for polio virus, there is a way to prevent it, and that's through a polio vaccine. Through vaccination and through the efforts of the World Health Organization and many other organizations that have contributed, eradication of polio is very real. The entire western hemisphere, including the United States, North America, Europe, are completely polio free. Now there are still cases in the world where polio exists, but the widespread eradication because of these vaccines has been considered one of the world's greatest medical achievements. And hopefully in the future polio can be completely eliminated by the widespread use of vaccination.