RESUMEN
The objective of this study was to determine which clinical features of typhoid and malaria are most helpful in distinguishing the two diseases among Papua New Guinean highlanders. In a study of 35 patients with culture-positive typhoid and 49 with blood-slide-positive malaria (Group 1), the odds of typhoid were increased most in patients with altered bowel habit, an illness of more than 2 week's duration, tremor or the presence of typhoid facies. The odds of typhoid were lowest in patients with pallor or jaundice. These findings were used to derive a clinical diagnostic algorithm, which was then evaluated in a further group of 34 typhoid patients and 41 malaria patients (Group 2). The sensitivity of the algorithm in diagnosing malaria was 91% in Group 1 and 71% in Group 2, with specificities of 85% and 79% respectively. For typhoid, the sensitivity of the algorithm was 85% and 79% for Groups 1 and 2, respectively, and the specificities were 91% and 71%. We conclude that the algorithm merits further evaluation in a primary health care setting and may prove useful in making an earlier diagnosis of typhoid.