there are over 200 different cold viruses. the more people contact that you have the more likely you will get one of them. especially in the fall and winter months. i do not think that three cold in four months is that unusual.
isn't it a bit much having 3 colds in 4 months? . had the first cold nov8 five days after a flu shot; dec9 was the 2nd head cold; jan gave me a break; feb10 i came down w/ a sore throat followed by cough body aches and chills adding a head cold on feb13; previously i had gotten one cold earlier last year and none before my arrival in puerto rico on jan'09; i'm a female 58 yo