There have been 6,431 cases of whooping cough (pertussis) reported in California so far this year, less than 200 short of the 1950 record which registered 6,613 cases for the whole year. With reports of new cases coming in at 174 per week, breaking that record is now a question of days, experts believe. Virtually all health care professionals agree that if vaccination rates had been higher, the total number of cases, hospitalizations and deaths this year would have been considerably lower.

The California Department of Public Health, Immunization Branch says the 6,431 confirmed, probable and suspect reported cases of pertussis include only individuals whose onset of symptoms started on or after 1st January, 2010, through to 2nd November 2010.

Across California, the pertussis rate is 16.4 cases per 100,000 people. This is the highest rate since 1958 with a state rate of 26 cases per 100,000.

Over the last week 174 new cases have been reported, of which 67% are confirmed, 16% probable and 17% suspect.

58% of all hospitalizations due to whooping cough have occurred in babies aged 3 months or less. 75% of all hospitalizations have involved babies up to 6 months of age.

76% of all babies hospitalized aged up to 6 months have been Hispanic.

  • There have been ten reported deaths
  • 90% of all deaths were Hispanic babies
  • 90% of all deaths were babies aged 2 months or less when symptoms onset began
  • 90% of all deaths were among patients who had received no doses of pertussis-containing vaccine
  • The other death involved a 2-month old baby who received his first dose just 15 days before symptoms began. The baby was a 28-week preemie (prematurely born)
  • Most cases of pertussis among babies have occurred in those aged 3 months or less

  • 322.5 cases per 100,000 in babies aged up to six months (highest rate)
  • 39.56 cases per 100,000 in children aged from 6 months to 6 years
  • 48.8 cases per 100,000 in children aged from 7 to 9 years
  • 35.5 cases per 100,000 in children aged from 10 to 18 years. A significant proportion of these were aged 10 or 11 years

  • 16.9 per 100,000 among Hispanics of all ages
  • 14.1 per 100,000 among Caucasians of all ages
  • 398.6 per 100,000 among Hispanic babies aged up to six months

Source: California Department of Public Health

Written by Christian Nordqvist