The first challenge that faces internists, writes Dr. Dworkin, is recognizing pertussis, which in some cases presents with mild symptoms; some adults won’t even have a cough.4 But at the other end of the disease spectrum, symptoms may be as brutal as bilateral subconjunctival hemorrhage or rib fracture due to convulsive coughing. In any case, what goes unrecognized, undiagnosed, and untreated becomes a particularly serious risk for vulnerable infants. Once pertussis is identified, positive results on polymerase chain reaction or culture can help convince skeptical colleagues who may still believe pertussis is exclusively a childhood disease—and a vintage one at that.
“What we in pediatrics champion … is for [these immunizations] to help the young child; the less disease we have out there, the better off we’re going to eventually be,” says Dr. Stucky, who projects that, within just a few years, Tdap vaccinations for adolescents and adults up to age 64 might lead to a reduction of infection in the three-month-old group.6
Measles and Mumps
From January 1 to October 7, 2006, 45 states and the District of Columbia reported 5,783 confirmed or probable mumps cases to the Centers for Disease Control and Prevention (CDC). (See Figures 2 and 3, above.)8 The Advisory Committee on Immunization Practices (ACIP) announced that continuing data from surveillance reports meant that healthcare workers should remain alert to suspected cases, conduct appropriate laboratory testing, and use every opportunity to ensure adequate immunity, particularly among populations at high risk.7
In contrast to the circumstances with pertussis, with mumps “there have been pockets of people who have either chosen not to immunize their child[ren], or their child[ren] get exposed to it somehow,” says Dr. Stucky, “and although they might be immunized, they might not have had a good response.” In an environment such as a school, “where one child can cough on a few and then cough on a few [more],” there is an environment where the infection can spread rampantly.
With mumps and measles, these could be called true outbreaks, such as the classic example that occurred in Kansas 18 years ago or the epidemic that disseminated from a college campus in Iowa in the spring of 2006, which originated from only two airline passengers on nine different flights within one week.8
College dorms and cafeterias can be treacherous breeding grounds for pathogens, and this generation of college students is susceptible for a few reasons. For one, in the late 1980s, when they were infants, the vaccine schedule was changed; the measles/mumps/rubella vaccine was upgraded from one dose to two—and not all children received the two doses.
The unimmunized who are exposed to measles and mumps remain at highest risk for spreading the disease. Although in 2005, 76%-79% of children aged 19-35 months received the entire recommended series of shots against whooping cough, diphtheria, tetanus, polio, measles, mumps, rubella, chicken pox, hepatitis B, and Haemophilus influenza type B, that still means that 21%-24% of the children—or potentially one out of five kids—did not.9
Other factors causing low levels of immunization include parents’ Internet-fueled fears of links to autism; immigrants crossing U.S. borders from Mexico or other countries where immunization is not standardized; religious and philosophical reasons; and international travel.10
“When young adults travel internationally [to places] where they are exposed to young children and adults who have never been immunized,” that’s a big risk, says Dr. Stucky. “All it would take is one [infected] student coming into a dorm and passing it around [to others with lapsed coverage or no immunization for the disease].” And while providers may think of travelers being exposed to diseases such as malaria and typhoid fever in developing countries, “in reality, a lot of the common things we’re immunizing for in our country are not immunized for in other countries, and those can be brought back.”