Even after an outbreak earlier this spring, pertussis (also known as whooping cough) may be on the rise again in Montana. Flathead county is currently struggling to contain an outbreak in five school districts.

"Since the beginning of October, we have 35 cases," said Community Health Services Director for Flathead County Jody White. "Usually we won't even see 35 in a year, so it is definitely unusual to have this many."

White says nearly all of the victims are school-age children, however the youngest victim in Flathead county is only 13 months old. Infants are especially vulnerable to pertussis as they cannot receive the full vaccine and suffer most from the side effects. Family members of infants are advised to make sure their vaccinations are up to date.

Many would assume that Flathead County's vaccination rate might be low, but it's not. White says the vaccination rate of Flathead County students is about average in comparison with other Montana counties.

"Pertussis is always present below the surface in a community," says White and although the recent explosion is difficult to explain, it appears that one of the main causes for spread in the Flathead is that sick individuals are choosing not to follow the prophylactic procedures the health department advises.

"The best prevention is immunization," White advises. "If you have a persistent cough for more than a week make sure you go and see your doctor." To learn more about pertussis and steps to prevent it, visit the Center for Disease Control website on the disease.