You can buy special cheese at stores to melt. It can be many different types of cheese.
A traditional recipe calls for quite a large quantity of shredded Emmental and/or Gruyere cheese. Both cheeses melt well and yield a nutty and mild, yet slightly sharp, fondue flavor.
Ingredients
Place in top part of double boiler and place directly on burner and bring to boil. Put pan in bottom of double boiler and add 4 cups swiss american cheese. Add 3 Tbl. cornstarch, softened with water. Stir until cheese melts. Put into fondue pot.
Many cheeses can be used but usually it is a mix of Emmental and Gruyere
Gruyere or fontina
Emmental (or Emmentaler) is a kind of Swiss cheese.
Cheese fondue is not typically made with havarti, usually one uses emental or gruyere, however, if you like havarti, then why not. It might be a good idea to mix it with some kind of Swiss cheese for the sake of consistency. Also, if you use havarti be sure not to add salt, as it is a rather salty cheese.
Gouda
cheddar jack or a rich kind
I would not say that there is some specific disease that is associated with fondue as compared to any other kind of food, however, food can go bad, and you can get sick from eating it, whether it is fondue or anything else.
Fondue, soup, pasta
The best substitue would be to use cottage cheese (the taste is similar). Drain the liquid from the cottage by placing it on top of cheesecloth that is placed over a bow.
"Brick" is not a kind of cheese, it is a form of cheese. Brick cheeses include but are not limited to cheddar, jack and mozzarella. The only form I would substitute brick cheese with is cheese curd because of moisture content.
Whole milk or regular cream is typically used.
a kind of cheese.
what kind of cheese do gerbils eat
Vinegar will adversely affect the cheese's fermentation process. Vinegar has acetic acid, which is of a different kind of acid than citric acid even though they are in the same pH range. The result would make the cheese possibly unsuccessful and unsafe to eat.