Review of Hospitalized Cases from Holland Patent School District
Because the data indicated an excess of normal surgically removed appendices in the Holland Patent School District residents during September 1976, the investigators attempted to identify additional cases by conducting a second review of hospital records that focused on children from that district who were hospitalized between September 1 and November 30. They broadened the case definition to include children with the discharge diagnosis of appendicitis, mesenteric adenitis, or regional enteritis instead of only children who had undergone appendectomies. Of children who underwent appendectomies, pathologic diagnoses were without exception stated as normal or lymphoid hyperplasia of the appendix.
A total of 33 children met the broadened case definition. Of these, 23 (70%) had onsets of illness during the 6-day interval from September 23 through September 28. Figure 2 (below) shows the dates on onset for all 33 cases.
Children from 5 Schools Hospitalized with Abdominal Pain and Fever, by Date of Onset, September – October 1976
What should we be interested in when we look at this figure? What does it tell us about this epidemic?
The mean and median ages of the 33 school-age children who met the broadened case definition were 11.2 years and 13.0 years, respectively. This means more older than younger children were affected. Also, twenty-three (70%) of the 33 children who met the case definition were males. What are possible explanations for the epidemic affecting more older than younger children, and more boys than girls?
Cases were seen in students from all five district schools, with hospitalization rates ranging from 3.1 to 19.8 per 1000 students per school. The overall hospitalization rate for the district was 12.4 per 1,000 students. What does this tell us about the epidemic?
Of the 27 cases with dates of onset during September, 13 underwent surgery. Signs and symptoms did not differ between those children who underwent surgery and those who did not.
The distribution of clinical manifestations of illness among the 33 children is shown in Table 2 below.