Santa Clara County returning to baseline numbers in war on pertussis

Santa Clara County is returning to its baseline after an unusually high rate of reported pertussis or whooping cough cases last year.

New numbers out April 4 indicate that the county has seen 99 reported cases of pertussis since Jan. 1, of which seven patients were hospitalized, according to the Santa Clara County Department of Public Health.

“In general, it’s a cyclical disease that peaks every three to give years,” according to Dr. Sara Cody, deputy health officer with the Santa Clara County Public Health Department.  “You would think we would come back down to baseline here in 2011, but we are still seeing more activity than you might expect due to an unusually high amount of cases in 2010.”

In a 16-month period beginning in January 2010, Santa Clara County saw a total of 560 confirmed, probable or suspect cases of pertussis, 30 hospitalizations and no pertussis-related deaths. Cody said pertussis was one of the top five illnesses reported to the public health department last year.

Statewide, there were 9,477 cases, resulting in 10 deaths and 663 hospitalizations. The number of cases in 2010 represents the most cases reported in 63 years since there were 9,394 cases reported in 1947, according to a California Department of Public Health Pertussis Summary Report issued last week.

Since early 2010, the city of Campbell saw 19 cases. The largest reported cases were found in San Jose with 296 ill, followed by Sunnyvale with 54 cases and Santa Clara with 43 reported cases, according to the county.

Pertussis, also known as whooping cough due to it’s persistent “whoop”- like cough, is a highly contagious airborne bacterial illness spread through coughs and sneezes. Pertussis is hard to diagnose, as its early symptoms are similar to that of a common cold, with runny nose, fever and cough.

But what distinguishes pertussis from the common cold is what happens in its second phase, according to Cody. After a couple of weeks, the pertussis infection causes intense coughing spasms that oftentimes leave a person gasping for air.

Babies often cough until they cannot breathe and older children, teens and adults frequently cough until they vomit or turn blue from lack of oxygen. The cough can last weeks and in some cases months before it tappers off.

The best defense against the disease is vaccination, as it is an extremely contagious disease.

“Because its so contagious, we must have a large amount of the population vaccinated in order to get what we call “herd immunization,” which would protect a majority,” said Cody.

Assembly Bill 354 might help in the state’s herd immunity. AB 354 mandates students entering or advancing to grades seven through 12 in the 2011-2012 school year to be immunized with a pertussis vaccine booster called Tdap, or Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis.

The new requirement goes into effect July 1 for one year and affects all students entering public and private schools.

“Our biggest concern is how to get the adolescents to get their Tdap – before entering schools,” said Cody. “Students attending have to have documentation that they have that booster.”

Who knows, wonders Cody, “maybe it will help contribute to a community-wide vaccination method.”