A disturbing theme has emerged in an analysis of all eight cases of California infants who died from whooping cough this year: Despite the patients' multiple visits to clinics and hospitals, doctors typically failed to make a swift, accurate diagnosis.
"In several cases ... the infants were treated only for nasal congestion or mild upper respiratory infection," Dr. John Talarico, an immunization official with the California Department of Public Health, wrote in a recent letter to healthcare providers statewide.
"By the time these infants developed severe respiratory distress, it was usually too late for any intervention to prevent their tragic deaths."
Because whooping cough, also known as pertussis, can be hard to diagnose, health officials urged physicians to suspect the bacterial disease in any infant under 6 months of age who is having trouble breathing.
"Infants presenting with a history of respiratory difficulty should be evaluated and treated for pertussis until proven otherwise during the pertussis epidemic," Talarico warned. Initial symptoms of the bacterial disease in infants are deceptively mild and can lull physicians into a false sense of security.
"It's a tough diagnosis because the babies, they don't look very sick. They don't have a fever. And they have a runny nose and a little cough," said Dr. James D. Cherry, a UCLA pediatrics professor and an expert on pertussis who has reviewed the eight infant deaths.
"All of those should've been diagnosed earlier. And a couple of them, even after they were diagnosed, the [healthcare providers] didn't take it as serious enough, quick enough," Cherry said. Delayed hospitalization contributed to fatal outcomes, he said.
Cherry said physicians who suspect whooping cough should order lab tests to confirm the diagnosis. Because infants can deteriorate rapidly, Cherry advised physicians to strongly consider hospitalizing them in a major medical center with access to an intensive care unit.
A quick diagnosis can lead to treatment with antibiotics, which can keep the patient from becoming gravely ill.
With children returning to classrooms this week, whooping cough is showing no sign of letting up in California.
"It's still on the upswing, and I think it's going to be accentuated with schools opening," said Dr. Jonathan Fielding, director of the Department of Public Health for Los Angeles County. "There is going to be increased opportunity for infection."
California is in its worst year of whooping cough since 1958, with 3,600 cases reported so far this yea, a seven-fold increase from the same period last year.
Put another way, it is the nastiest season since pertussis rates began a sharp decline, falling in the 1940s and 1950s after widespread inoculation efforts began.
Of the eight infants who have died, all were younger than 3 months old. Four of them died in Los Angeles County.
Whites have been hit hardest by the disease overall, but among infants younger than 6 months old, Latinos suffered the highest rate of illness.
Infants are at the highest risk of complications and death because their immune systems are weak and they are too young to have completed the first set of inoculations.
Health officers in Los Angeles and San Francisco are warning that if the bacterial disease spreads in schools, unimmunized children might be barred from attending classes until the outbreak is over.
The warning has caused unhappiness among some parents philosophically opposed to vaccinating their children.
"I will be so sad if this goes through and our district follows suit and [my child] is excluded from her first weeks of school," a person with the username EVC wrote on a message board on mothering.com. "It seems so unfair to me ... if [my child] is healthy (which I hope she will be), why should she be excluded?"
The reason, according to health officials, is that the child could become seriously ill and infect others.
Cherry emphasized that infants are commonly infected by family members, such as the mother, father and older siblings who haven't been properly diagnosed.
"Doctors who care for adults should definitely be more suspicious of this," Cherry said.
Fielding said that as school resumes, parents should keep sick children home and teachers should be alert about the spread of illness in the classroom.
Because immunity to the disease can begin to fade five years after illness or inoculation, officials urged people to make sure their pertussis vaccinations and their children's are up to date.
In July, California health officials expanded their recommendations for who should get a Tdap pertussis booster shot to include anyone 7 years old or older who is not fully immunized, the elderly, and especially pregnant women and anyone who has contact with them or with infants.
"I would think -- in the presence of an immediate danger to health -- that people would go and get immunized," Fielding said.