Human: I've heard that a lot of people get strep throat when the weather changes. Is that true? Assistant: 
Yes, it is true. Strep throat can be caused by viruses and bacteria. The most common cause of strep throat is Group A streptococcus (GAS). GAS is found in the throats of about 25% of adults and 10% of children. It's spread through close contact with an infected person or through droplets in the air. People who have frequent contacts with other people are at greater risk for getting strep throat.