Rabies Lyssavirus - The Deadly Virus of Mammals with No Cure

Did you know that in the 1960s and 1970s, chicken heads rained on the ground? Actually, it wasn't a result of evaporation and condensation, rather it was the government of Sweden in Europe air-dropping chicken heads from planes to various parts of the country. About 1 million Vaccine-Loaded Chicken heads were air-dropped to red foxes to combat rabies.

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Rabies Lyssavirus is one of the most deadly viruses known to humans but it isn't common now, so you might have not seen someone who actually has the Lyssavirus. Named after the Greek Spirit Lyssa (Lytta) which is the mad rage, and frenzy, the virus after infecting animals will make them violent and angry creatures, as well as make humans anxious, and angry, making them have a phobia of water.

Viruses, such as the lyssavirus, are unique entities that fall somewhere between living and non-living organisms. They require a host cell to replicate and thrive. The lyssavirus contains five structural genes (N, P, M, G, and L) that enable its existence and functionality. These genes facilitate infection in both animals and humans, help the virus evade the host's immune system, travel to the brain, multiply, and spread to new hosts.

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While so many animals including bats can have the rabies virus (lyssavirus), dogs are most likely the animals to transfer the virus to humans. This happens via a bite from the dog that transmits the virus through saliva which allows the virus to reach the tissue of humans. When the virus gets into the tissue, they head for the nerve cells which transfer signals from the brain to the body. These informations are transmitted through axons and this is where lyssavirus go to through receptors in the neurons where it begins to multiply. The virus uses Dynein and kinesin to reach the neuron nucleus but while the cells will produce interferons in the case of infection (virus), with lyssavirus, it doesn't produce any interferon thereby not causing the immune system to attack it.

The journey of the lyssavirus to the brain can take weeks, months, or even years, depending on the location of the bite and the time required to reach the brainstem. Any killer T-cells attempting to attack the virus are either deactivated or killed through apoptosis. Once the brainstem becomes compromised, it can lead to the death of the infected individual.

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Interestingly, the brain tissues of people with rabies do not show large damage, the damage is minimal or non-existence, but then how do people die. The virus affects brain neuron communication, leading to agitation, confusion, and aggression. The virus becomes saturated in the salivary gland and is ready to infect someone from a bite. The brain starts to swell and when symptoms start to show, it is surely going to lead to death.

While diseases like smallpox have been eradicated and treatments have been developed for viruses such as Ebola, Covid-19, and HIV, there is no known cure for Rabies Lyssavirus once symptoms begin to manifest. However, there is a preventive measure available in the form of a vaccine. The Lyssavirus vaccine, also known as ABLV, is highly effective in preventing and neutralizing the virus before symptoms emerge. However, once the virus takes hold and symptoms appear, no known remedy can halt its progression.

One reason why people who have a thing against vaccines are still able to stay with their beliefs is that Lyssavirus is a slow virus that can take weeks, months, or years to manifest. Rabies Lyssavirus remains one of human's deadly and incurable threats.

Rabies Lyssavirus - The Deadly Virus of Mammals with No Cure

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