Colorado health officials are urging people to make sure their vaccinations are up-to-date following an outbreak of whooping-cough.
Health officials say In the last two weeks of October, 100 cases were reported in Colorado.
According to a report the Associated Press, last year was the worst year on record for whooping cough in Colorado, with nearly 1,500 cases reported.
Whooping-cough is highly contagious. It starts like the common cold, but after one or two weeks, severe coughing can begin and last for more than 10 weeks.