ABSTRACT: In response to publicity about an alleged but erroneous link between vaccination and autism, the number of children who are being immunized has decreased. This is of concern because many vaccine-preventable diseases have potentially devastating and even lethal consequences. Numerous studies have negated the role of vaccines in the environmental causation of autism. Most compelling are those studies that show no relation between vaccination status and autism. The evidence for a genetic etiology is strong. There is a 60% to 90% chance for an identical twin and a 5% chance for a sibling to have autism if a relative is affected. Studies of familial cases highlight particular chromosome regions and predisposing genes. The evidence implies that multiple variant genes and the environment interact to cross a threshold and produce autism. Pediatricians can reassure worried parents that medical science has demonstrated that there is no link between autism and vaccines, and that parents can feel safe in immunizing their children.
|A. Since the introduction of Hib conjugate vaccines, the incidence of invasive Hib disease in young children has declined significantly. (Courtesy of Jeff A. Beck, MD, and Jeri Weyher Kessenich, MD.)|
Case 1. An older attending physician listens during morning report to the details of the case of a child with suspected croup and decreased oxygen saturation. The resident mentions that he inspected the child’s mouth and pharynx as part of the routine examination. The attending recalls a case 20 years ago when a 2-year-old girl came to the emergency department with fever and stridor so severe that she was forced to sit erect to breathe. How different the examination was then—with observation for drooling, lateral neck radiographs for evidence of a dilated hypopharynx, and careful inspection of the throat when personnel expert at intubation were available. Examination under these conditions might demonstrate a cherry-red mass in the posterior pharynx projecting above the tongue.
|B. This infant has small eyes and bilateral cataracts from congenital rubella. (Courtesy of Alexander K.C. Leung, MD, and Reginald S. Sauve, MD.)|
Case 2. A newborn, born at full term, presents with a "to and fro" heart murmur at the upper left sternal border. The baby’s length and weight are at the 50th percentile for his age, but his head circumference is below the third percentile for age. Subsequent follow-up reveals that the infant has profound sensorineural deafness.
|C. These lesions are those of a streptococcal infection secondary to varicella. (Courtesy of Kathryn S. Moffett, MD.)|
Case 3. A young girl presents with a peripheral vesicular rash accompanied by high fever and cough. Her health improves somewhat on the third day of illness with fluid therapy, and then worsens with increased fever, respiratory distress, and lethargy. Admission studies demonstrate hypovolemic shock and increased coagulation times, and the child is transferred to the pediatric ICU and placed on mechanical ventilation.
What is the diagnosis in each case—and how could these disorders have been prevented?
(Answers and discussion on the next page.)
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