Table 1.

Frequency of measles neutralizing antibody by study group

Study group*	N	Measles seroprevalence†	95% CI
Group A1	17	100	90–100
Group A2	38	86·8‡	75·3–98·3
Group B1	24	100	91·5–100
Group B2	18	100	90–100
Total	97	94·8

CI, Confidence interval.

^*Group A1: HIV-infected individuals presumed to have naturally acquired measles infection. Group A2: HIV-infected individuals presumed to have acquired immunity after measles immunization. Group B1: Non-HIV-infected individuals presumed to have naturally acquired measles infection. Group B2: Non-HIV-infected individuals presumed to have acquired immunity after measles immunization.

^†Neutralization antibody titre ⩾32 mIU/ml was considered as protective antibody level.

^‡P = 0·008