Magnitude of malaria-specific CD4⁺ T cell responses and protection from symptomatic malaria.

Note: HR: Hazard Ratio; IRR: incidence rate ratio; PRR: prevalence rate ratio. Numbered rows refer to cell populations described in Figure 2. Associations in row 3 are not applicable because these responses were undetectable. Multivariate models controlled for duration since last malaria infection. Similar results were obtained when controlling for cumulative episodes over prior 3 years and for the presence or absence of parasitemia.