Southwest Colorado has seen fewer than usual cases of whooping cough the exact opposite of the rest of the country, including Colorado as a whole.
Nationally, the number of cases of whooping cough (pertussis) could end up higher than at any time in the last 50 years.
Three cases of whooping cough have been recorded in Archuleta, La Plata, Montezuma, San Juan and Dolores counties from January through June, the San Juan Basin Health Department reported Friday.
The five-year median in the five counties is seven cases, said Jane Looney, a spokeswoman for the health department.
Colorado as a whole is following the national trend. In the first six months of the year there were 482 cases of whooping cough, Looney said.
The states five-year median is 119 cases, Looney said.
The Centers for Disease Control and Prevention has recorded 18,000 cases of whooping cough so far this year, more than twice the number seen in the first six months of 2011.
If the current rate holds through the rest of the year, the number would the highest since 1959, when 40,000 cases were recorded, agency said.
Bari Wagner, the regional epidemiologist at the San Juan Basin Health Department, said the region has been lucky so far.
But no one knows what can happen, she said.
Wagner recommended that adults, 19 years of age and older, get a Tdap vaccination to protect against whooping cough.
A properly vaccinated adult, particularly those who are around children, protect themselves and children who are not yet fully immunized, Wagner said.
Infants get pertussis vaccinations at 2, 4 and 6 months, Wagner said. But they arent fully immunized until they get a booster shot at 5 years of age.
Adults can get pertussis vaccinations from their provider or at the health department.