Why is a disease like osteoarthritis not considered an infectious disease?

Non-infectious diseases are those that are not contagious because they can't be spread from one person to another. Non-infectious diseases are caused by factors, like genetics, environment, and lifestyle behaviors. 
Osteoarthritis or degenerative arthritis is a joint disease caused by cartilage loss in a joint and can be caused by aging, heredity, and injury from trauma or disease.

Well, both latitude and intensity of light affect temperature because, the higher the light intensity, the higher the temperature and since latitude is the measure of how close you are to the equator, then the closer to the equator you are, the higher the temperature is.

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