How long is the incubation period for Feline Calicivirus?
The incubation period, the period between the time the cat get the virus and untill it shows symtomps varies from 2 to 10 days
 
What are the symptoms of the Feline Calici Virus in cats?

  • Nasal discharge (typically clear colored but may progress to pus-colored)
  • Sneezing
  • Inappetance/anorexia
  • Discharge from the eyes (typically clear colored but can progress to pus-colored)
  • Squinting of the eyes (which may be due to ulcers of the cornea)
  • Lethargy
  • Difficulty chewing food (due to ulcers on the tongue and in the mouth)
  • Drooling (due to ulcers on the tongue and in the mouth)
  • Pink eye signs (e.g., redness of the eyes due to secondary inflammation of the conjunctiva)
  • Ulcers in the mouth
  • Noisy breathing
  • Increased or difficulty breathing
  • Dehydration
  • Fever
  • Death (rare)
 
How long does the Feline Calicivirus live in the environment?
"Susceptible cats can get an infection by direct contact with another infected cat or by environmental exposure to objects that have been contaminated with infectious secretions."
The virus may survive for up to one week in a contaminated environment (and possibly longer in a cool, damp location). 
 
Can cats get calicivirus twice?
Feline calicivirus exists as a wide variety of strains, meaning a cat can get infected many times throughout its life, in a similar way to humans picking up a common cold time and again. It's a common misconception that cats will never rid themselves of FCV once first infected.
 
How common is calicivirus?
To start with, here are a few key facts about feline calicivirus in general: FCV infection is common even in healthy-appearing cats: up to 25% of asymptomatic cats from multiple-cat environments such as shelters and catteries, and up to 8% of pet cats, will be shedding FCV from the oral cavity at any given time.
 
What percentage of cats have calicivirus?
Feline calicivirus (FCV) is found in up to 40 percent of cats.
It commonly causes a self-limiting upper-respiratory infection, but a rare, virulent strain can cause fatal inflammation of the liver, intestines, pancreas, and cells that line the blood vessels.
How do you disinfect calicivirus?
The housing of these cat/s in a bathroom is recommended so the floor and surfaces can be disinfected.
But of course, it's not necessary, but the fewer surfaces you have the easier it is to clean, of course, the most important is to split them up into groups if you do have a large group, make a space that is really clean where you move the cats who recovered completely. 
All surfaces should be cleaned, then disinfected with a 1:32 bleach solution or trifectant and allowed to remain on the surface for ten minutes, or air dry.
Virkon S is effective for many diseases: https://virkon.se/hund-katt/, this might be available only in Scandinavia but I think a tip is good since it's completely harmless but kills most viruses and bacteria. 
 
How long does Feline calicivirus last?
How long does a typical calicivirus infection last?
Once a cat is exposed to calicivirus, it will go through an incubation period of 2-6 days before developing clinical signs which typically last for 14-21 days.
During this entire time, the cat will potentially be infectious to other cats.
 
How do you treat Calici in cats?
Currently, there is no treatment to stop the virus, but pet owners can offer supportive care for their cat while its immune system fights the infection.
Most cats can recover at home, but severely affected cats may need intensive nursing care. Most important is to make sure the cat eats, since they become snotty and got stuffed noses they might lose their smell and therefore not be very keen on eating. Noses can be treated with normal nose drops both with a decongestant (for a short while or just a couple of times) or saline solution. Keep the noses as clean as possible.
Can calicivirus in cats be cured?
There are some particularly virulent strains that can be fatal, but most cats infected with calicivirus fully recover. 
There is no cure for calicivirus, but if your cat becomes infected you should bring them to the veterinarian because the vet can treat their symptoms so the cat feels more comfortable.
 

Is calicivirus fatal?
One particular strain of calicivirus, known as Feline Calicivirus-associated virulent systemic disease (FCV-VSD), makes cats very ill and can be fatalFortunately, this viral strain is rare.

 
Does calicivirus cause diarrhea? 
In more severe and systemic cases, it can cause vomiting, diarrhea, edema (swelling from fluid accumulation), skin lesions, and pneumonia.
 
 
https://www.royalcanin.com/us/cats/kitten/calicivirus-in-cats
https://effinghamanimalhospital.com/2020/12/21/feline-calicivirus/