pathogenic-pedagogy

[pathogenic-pedagogy]

Lyssavirus rabies: Rabies Virus Disease.

CW: SICK ANIMALS|ANIMAL DEATH

Hypothetical: A few months ago while walking your dog, you see a stray dog wandering aimlessly in the park. It is howling, whining, yowling rhythmically and repetitively. Its jaw is dropped, hanging open, tongue lolling out of its mouth as if choking on a bone. You cautiously approach it, and it immediately whips its head to you, movements awkward and shambling. Before you can decide to retreat, it roars with rage and moves fast to attack with a mouth full of teeth and foam. Your best friend immediately moves to defend you and sustains a nasty, bloody bite wound to her flank. What if your dog wasn't vaccinated? She would become something unrecognizable to you, if she weren't euthanized before her suffering began. And what if you had been alone? Lyssavirus rabies is the causative agent of rabies. It is an enveloped, negative-stranded RNA virus that infects nervous tissue.

Classification

(unranked): Virus

Realm: Riboviria

Kingdom: Orthornavirae

Phylum: Negarnaviricota

Class: Monjiviricetes

Order: Mononegavirales

Family: Rhabdoviridae

Genus: Lyssavirus

Species: Lyssavirus rabies

Name breakdown--Lyssa was a minor Greek goddess of frenzy, rage, and rabies. Rabies similarly translates roughly to 'madness' or 'rage'.

Host Range and Transmission

Rabies is a zoonotic virus with an extensive host range, mostly mammalian. Lab work has shown it can reproduce in bird, reptile, and even insect cells. It's been recorded throughout human history as early as 2000 BCE. It was first recorded in ancient Mesopotamia.

The virus is transmitted through saliva. Dog bites and scratches are responsible for 99% of rabies cases worldwide. Bats are another potential vector of transmission, especially in the Americas where there are rigid vaccination procedures for dogs. Wild mammals (foxes, raccoons, skunks, etc.) can also transmit the disease. There has never been a confirmed case of human-to-human bite transmission (though possible, theoretically).

Symptoms

Rabies is a neurotropic virus (infecting the nervous system). It eventually causes fatal swelling of brain and spinal tissue. After being bitten by an infected animal, though the average incubation period is 2-3 months, it can take from one week to one year depending on bite location and viral load introduced. Hydrophobia is one of the most iconic symptoms of Rabies--historically, rabies and hydrophobia were synonymous. The perceived fear of water is caused by the contractions in a person's throat when they swallow or even think about swallowing water. Other symptoms may include: Fever, Headache, Nausea, Vomiting, Agitation, Anxiety, Confusion, Hyperactivity, Difficulty swallowing, Excessive salivation, Insomnia, and Hallucinations.

There are two primary presentations of rabies: Furious Rabies and Paralytic ("dumb") Rabies.

Furious rabies involves hallucinations, hyperactivity, and extreme aggression. This form most often manifests "hydrophobia" symptoms. (80% of human cases). Paralytic "dumb" rabies causes paralysis and coma. (20% of Human cases).

There isn't currently a strong answer for what causes the differences in manifestations, though some experts suggest it could have to do with the animal vector, the bite itself, or have to do with the patient's immune function. Once symptoms onset, the fatality rate is 100% Aside:Jeanna Giese was a teenage girl who managed to survive a late-stage rabies infection through what's now known as the Milwaukee protocol. She was put into a chemically induced coma and given a cocktail of antivirals, and her infection passed over. However, this method hasn't proven to be extremely successful and is heavily criticized for its ethics.]

Spread, Prevention, and Epidemiology

Rabies-related deaths are most common in African and Asian countries. In 2015, the highest counts of deaths by country in descending order were India, China, and the Democratic Republic of Congo. Rabies deaths are higher in low-income countries where cases are often underreported. Aside: In India, a psychogenic illness called Puppy Pregnancy Syndrome (PPS), where victims bitten by a dog become convinced they're pregnant with puppies, is hypothesized to harm efforts to eradicate the virus in the country. Patients often seek treatment from faith healers rather than medical professionals. (Some psychiatrists consider this a culture-bound disorder. Perhaps a future post!).

RABIES IS PREVENTABLE! Rabies vaccinations in canines have proven extremely effective in eliminating most cases of human infections in communities. If someone is bitten, there are vaccines globally available. Aside: Louis Pasteur was the first to vaccinate a young boy against the Rabies Virus by injecting him with a weakened version of the virus post-bite. Louis Pasteur also pioneered pasteurization (as the name would imply!)

Remember: vaccinate your pets. For a healthy world!

References + More Information:

Carter, John; Saunders, Venetia (2007). Virology: Principles and Applications. Wiley. p. 175. ISBN978-0-470-02386-0.

(www.dw.de), D. W. (n.d.). Medicine challenges indian superstition: Asia: DW.DE: 31.12.2012. DW.DE. https://web.archive.org/web/20130131194746/http://www.dw.de/medicine-challenges-indian-superstition/a-16489334 World Health Organization. (n.d.). Rabies. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/rabies

Hampson, K., Coudeville, L., Lembo, T., … Global Alliance for Rabies Control Partners for Rabies Prevention. (2015, April 16). Estimating the global burden of endemic canine rabies. PLoS neglected tropical diseases. https://pmc.ncbi.nlm.nih.gov/articles/PMC4400070/

Pattnaik, P., Mahal, A., Mishra, S., Alkhouri, A., Mohapatra, R. K., & Kandi, V. (2023, December 13). Alarming rise in global rabies cases calls for urgent attention: Current vaccination status and suggested key countermeasures. Cureus. https://pmc.ncbi.nlm.nih.gov/articles/PMC10784771/

Dr. Liji Thomas, M. (2022, February 3). Furious rabies vs dumb rabies. News. https://www.news-medical.net/health/Furious-Rabies-vs-Dumb-Rabies.aspx Videos! Professor Dave: Rabies Virus https://youtu.be/OvRxDQdAtGc?si=pWrwIJuEpyCmNeo5 Rabies in Dogs and Cat exhibiting Rabies symptoms (Content Warning: Sick Animals) https://youtu.be/PTCUNn56Fpo?si=EkygavbxhD6hXwMD https://youtu.be/H8fbAFOMTp4?si=xQeWDFRz8AkmvHOd short video about the first rabies vaccine https://www.youtube.com/watch?v=BWqD4H_ExgI&t=5s

[pathogenic-pedagogy]

Hello, Welcome to pathogenic-pedagogy

-To refer to me (the owner of this blog), you can call me Phage (He/Him). -I am currently an undergraduate student and a microbiology major. This is not an opinion|thought blog, and the aim is to be as strictly informational as possible! -I am using this blog as an extracurricular activity to study for my classes, as well as spread awareness of things I care about (public health and disease prevention.).

-I may get things wrong! Though my posts are informed by my current level of education and thoroughly researched sources, I am human and don't have a pHd (yet!). If I get something wrong, I urge you to send me an ask or message with the proper sourcing so I can correct my mistake as fast as possible. Science is a self-correcting body of knowledge! That's what makes it great! -Content discussed on this blog may be disturbing. I will be primarily talking about disease and health crisis, human and animal. -I urge that any interaction with this blog involving case studies , clinical writings or pictures maintain respect. Pictures may be 'gross', or a disease may not be a problem in your country, but real people still suffered. -Photos are open-access creative commons. If I've made a licensing mistake please contact me!

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