Fever

The Glashani believe they were originally born of storm itself. This is due to a powerful blizzard-like force raging in them from a very young age. They spend their early lives learning to quell that force to avoid an eruption of that storm by harnessing this internal magic against itself, producing a warmness to balance the frigidity. Even Galarian children start inexperienced though, and some find themselves pushing that warmth to a roaring fire which they no longer control. These two forces of fire and ice begin to spiral in a fit to outdo one another leading to Fever.
Fever leaves the child in a catatonic state where their icy body sits at a scorching 220 degrees. Those who have brushed a child's skin in this state can get hoarfrost boils: a condition where a blister forms from the intense heat while the fluid inside instantly freezes due to the cold emanating from all Glashani.

Transmission & Vectors

Fever does not appear to be contagious in the traditional sense. The illness is triggered by an imbalanced state within the afflicted. However, due to stress being a common cause, there is ample evidence of one Glashani increasing the chances another also catches fever. This is especially prevelant in children who have not built the emotional and mental fortitude necessary to avoid losing control.

Causes

The primary cause of fever is an imbalance between the competing forces inside of each Glashani. This can be triggered in a few ways however.

Vitraxine

Glashani appear to have an allergy of sorts to raw vitraxine. It acts as a catalyst causing both the storm and the Glashani's counteracting warmth to swell. A Glashani, adult or otherwise, who enters a vitraxine mine is nearly guaranteed to catch fever. As such, Glashani have an aversion to using vitraxine of any kind even though vitraxine based items do not to have the same effect on them.

Inexperience

Most Glashani that catch fever are children. This is because they have not learned how to balance their warmth against the storm. If caught early, this form of fever can be reversed without medical attention.

Trauma

While most Glashani are able to endure great trauma while keeping their balance in check, their internal warmth is powered by emotion. Traumatic experiences can lead to Roaring Fever, a variant in which the patient bypasses the initial stages of Fever and erupts immediately.

Symptoms

Warning Signs

Irritability It is rare for Glashani to become irritable due to their training. This training can lead to the afflicted concealing their irritation unfortunately, meaning that this symptom is not usually visible until later stages.
Cold Snap During sleep, Glashani are more susceptible to the storm. In normal circumstances, they are able to keep their emotional state placid even in dream states. This control is the first to go leading to their internal temperature rising in the deepest depths of slumber before cooling as they wake. Glashani sweat profusely at hot temperatures due to their elemental makeup. This can lead to multiple gallons of water soaking the bed underneath them before freezing as the Glashani transitions from deep sleep into light sleep and ultimately awakening. Often, this will lead to the afflicted to be frozen to their bed which, when alone, is fixed by stoking their internal flames which exacerbates the issue. Colloquially, this symptom is known as "icy bed syndrome" or "having a frozen night".

Fully Onset Symptoms

Catatonia The emotional turmoil is exhausing for the afflicted. Once the storm and fire start feeding one another, the Glashani is consumed by the fight leaving them with no ability to keep their more advanced functions running.
Spontaneous Storm Squalldancers of the Glashani are able to manipulate the weather around them intentionally, but they do so with great care as it taxing on their body. a Glashani with fever is unable to control these manipulations which can lead to storms erupting around them at various times. As the illness progresses, the storm becomes permanent until treatment or death of the afflicted.
High Internal Temperature Glashani can handle the heat of the hottest desert and as such temperatures that lead to the level of sweat to cause Cold Snap are immense. Also, an observer who touches a feverridden Glashani will develop hoarfrost boils: a condition where boils spontaneously develop but freeze upon breaking contact.
Eruptive Death If left untreated, a Glashani can lose the internal battle leading to a spontaneous eruption.

Treatment

Treatment is difficult as the afflicted is ultimately the only one who can bring balance back to their internal struggle. There are a few options that one can use to increase their chances.
Emotional Magic Casting spells that help reduce anger and frustration have shown affective in reducing the internal storm's power. This can allow the Glashani to reduce their internal flame, leading to a reverse snowball effect.
Vitraxine Amulets These provide provide more powerful relief over a longer period of time than short-lived spells, but due to the aversion to the material by Glashani are often only used in the most advanced cases.
Cold Comfort* Silvery pellets used to generate ice can be taken orally to help reduce temperatures.
Elixir of Calm An alchemist in Library of Certa is reportedly working on an elixir that can strengthen the will of the Glashani and reduce the temperatures. Current evidence shows it could reduce eruptive deaths by as much as 80%.

Prevention

The Glashani are taught at a very young age to control their emotions, even during dreams. Keeping a placid nature, not just superficially, is the primary prevention method. While vitraxine amulets can be used to calm emotions, the Glashani aversion to the material means they are often only used in severe cases to avoid eruptive death.

History

The Glashani people had once been respected members of Slovengaard society due to their ability to subtly affect the weather without the use of vitraxine. This intermingling meant spending time with children of other races that do not understand the unusual situation their icy peers have to endure.

Devastation of Hvarnan

In 124 PVE, a small city of about 12000 people called Hvarnan had about a thousand Glashani in their populace. Colqui, the official Squalldancer, had a son named Atlo. Atlo, having been the fourth generation to be born in the city had grown to connect himself with the more tempermental population than that of his ancestors. He ignored his father's constant warnings to keep calm, avoid outbursts, and spend time focusing on the storm inside him. One morning, Atlo woke up to find himself frozen to his bed. Now known to be a common symptom of the early stages of Fever, the boy did not know this. Instead, he knew he was freezing and mildly embarrassed by his current predicament. He fanned his internal flame to finally crush the storm every Glashani must fight in hopes of ridding himself of this nuisance. He felt the ice melt below him pouring off the bed. Then that water started to simmer and steam. The maelstrom grew in strength even as its winds fanned the internal flame ever higher. The bed began to dry, before it all stopped. The buffeting winds inside had ceased letting the flames die back down. Atlo believed he was free of the storm and smugly went off to brag to his friends. Unfortunately, this calm meant he had been taken by the Fever. Atlo's second heat wave happened around thirty or so other children, twelve of which were other Glashani. This one was even more uncontrolled. He began to rush home only to find his temperature continue to rise as the storm and the fire fueled one another. Eventually, the heat grew so intense he passed out.
He later awoke to find himself in the infirmary with three of the other Glashani children. They too had begun to show signs of this new disease. Unfortunately, only Atlo knew about the false security of the calm and had not been awake to share that news: the other nine had already been sent home. Colqui, who had been a half mile outside of town redirecting the main brunt of a powerful blizzard saw the smoke from the village. Over eight thousand people died. Today, the Hvarnan Ruins are all that remains.
The Glashani found their unique magic which had brought them respect now only brought hateful mobs. They escaped to a remote part of Slovengaard where storms run constantly, making them incredibly dangerous for others and used their magics to create pockets in this everlasting maelstrom to take refuge.

* Cold Comfort is an item from Pathfinder Second Edition which my world is built for. The unique use of having it eaten by Glashani was my only addition

Origin

Magical

Cycle

Short-term

Rarity

Rare