Pertussis is Back
Just like Britney Spears, whose career died and then came roaring back, Bordetella pertussis (B. pertussis, or whooping cough) is back with a vengeance. It's one of those illnesses that everyone thinks was wiped out because kids have been getting vaccinated against it since the 1940s.
But despite the continued high level of vaccinations, Pennsylvania's Department of Health just issued a health warning of unusually high levels of pertussis, and California has reported an epidemic, with 2,774 cases confirmed in 2010 alone. According to the New York Department of Health, "Since the 1980s, the number of reported pertussis cases has gradually increased in the United States. In 2005, over 25,000 cases of pertussis cases were reported in the United States, the highest number of reported cases since 1959. Approximately 60 percent of the cases were in adolescents and adults."
For some people, their first thought might be, "Serves those parents right who refused to vaccinate their children." But they'd be wrong.
So whence the comeback of pertussis? According to the U.S. Centers for Disease Control, a 2009 study of the pertussis virusin the Netherlands showed that variations in the virus have produced a higher level of pertussis toxin (Ptx), and that this has led to the resurgence of the disease. What this means is that the virus strains have become more infectious, compromising the efficacy of the vaccine and making the disease more contagious. Plus, the effects of the vaccine diminish over time, so adults may have lost their protections. Says Dr. Tom Clark, an epidemiologist with the CDC, "Immunity wears off, especially for adults who are decades past their most recent vaccination."
Pertussis spreads from person to person by direct contact with mucous droplets. In other words, you get it from infected people who cough or sneeze in your presence, and it's highly contagious. Early symptoms resemble a mild cold -- runny nose, sneezing, low-grade fever, mild coughing -- but then it blossoms into a severe cough within several weeks, causing severe inflammation of the lungs. The cough may be accompanied by whooping or gasping for breath, vomiting, seizures, and pneumonia. Standard medical treatment is with antibiotics, typically azithromycin (Zithromax), erythromycin, and clarithromycin (Biaxin).
Once the disease develops, it can take a long time to recover, even after treatment with antibiotics. According to Dr. Stephen Ostroff, Pennsylvania's acting physician general, "Think of it like a tornado going through your neighborhood. The tornado may go through relatively quickly, but it takes a long time to clean up the damage. That's true of this infection as well."
Part of the problem is that adolescents and adults, in whom pertussis is most prevalent, tend to wait for weeks before seeking medical care for a cough. When they finally do go to their doctor, the physician may not think of pertussis as the cause. According to Dr, Clark, "You only begin to think about pertussis when it's been going on for weeks and weeks and then treatment is much less likely to make a difference, and you've spread it to other people." Plus, testing to confirm pertussis is not that reliable. It may take several weeks to get results from a culture of nasal secretions. And while there's a quicker genetic test based on a cheek swab, not all labs perform it. The kicker is that both tests are only reliable in earliest stages of the disease -- much earlier than most people seek care.
So what can you do to avoid falling prey to the disease? Many in the medical establishment suggest getting a booster (Tdap) of the DTP vaccine if you're between the ages of 19 and 64 and haven't previously received it. This vaccine ostensibly protects against diptheria, tetanus, and whooping cough. On the other hand, it's not going to be that effective against the newer strains of the virus with the higher levels of pertussis toxin. It's also worth noting that the vaccine has been controversial given the serious side effects it may trigger, including permanent neurological damage, brain injury, seizures, allergic reactions, and death. Most physicians feel the risk of whooping cough far outweighs the purportedly slim risk of vaccine side effects, so you may indeed have a physician recommend the booster to you if the current trend of increased disease incidence continues. Plus, there is a new, less dangerous iteration of the vaccine now out, called the acellular version, as opposed to the whole cell vaccine. If you do get talked into a vaccine, at least insist that it be the acellular variety. It appears, though, that some emerging strains of bacteria have already become resistant to the acellular vaccine.
If you don't want the vaccine, how can you avoid whooping cough? Steer clear of anyone coughing, sneezing, wheezing, wiping his nose or displaying cold symptoms. If you must mingle with the potentially sick masses, the usual advice applies. Wash you hands well after being out in public and look to natural immune boosters and pathogen destroyers -- to which no bacteria can become resistant.