(September 11, 2012)--The Texas Health Department has issued a pertussis advisory citing the most deaths in a single year since 2005.

Pertussis, or Whooping Cough, is a very contagious bacterial illness usually spread by coughing or sneezing and often starts with cold-like symptoms and a mild cough, health officials said.

The state has seen six deaths and more than 1,000 confirmed cases of pertussis so far this year.

Five of the deaths were among infants under two months old.

At two months the first pertussis vaccination is recommended.

The sixth death was of an unvaccinated older child with underlying medical conditions, the health department said.

According to health officials with the department, there were a total of 961 cases of pertussis in the state last year, down from a peak of 3,358 in 2009.

Doctors say the best way to stay protected against the illness is to get vaccinated.

Patients who have pertussis are advised not go back to work or school until they’ve had five days of antibiotic treatment.