We find that CRP POCT in Chiang Rai and Yangon interacted with fever patients’ preexisting conceptions of illness and medicines, their treatment-seeking behavior, and their health-care experiences, which has led to new interpretations of the test, potentially unforeseen exclusion patterns, implications for patients’ self-assessed illness severity, and an increase in the status of the formal health-care facilities that provide the test. Here, CRP is linked to Fever.