Table 6.

Vaccine efficacy against overall mortality in randomised trials of an early two-dose measles vaccination schedule compared with the standard dose of measles vaccination at 9 months of age

Country and period	Age interval	Comparison (vaccines)	Administration of DTP	Deaths/person-years or persons	Mortality rate ratio (95% CI)	Comments
Sudan87 1989–1992	5–9 months	MV vs control (Meningococcal A + C)	DTP not given simultaneous with MV but could have been given after MV	1/60.5 vs 6/61.2	0.18 (0.02–1.54)	1st vaccine in 2-dose group was Connaught HTMV and 2nd dose was Schwarz standard MV
	9–36 months	2nd vs 1st MV		7/371.6 vs 7/355.9	0.96 (0.34–2.73)
	5–36 months				0.60 (0.25–1.45)*
Guinea-Bissau88 2003–2009	4.5–9 months	MV vs control (no vaccine)	DTP not given simultaneous with MV and after MV; all had DTP3 1 month before enrolment	5/398.8 vs 29/821.8	0.33 (0.13–0.86)	Vitamin A supplementation (VAS) at birth is not official policy. Hence, only results for children who did not receive VAS are presented*
	9–36 months	2nd vs 1st MV		20/2054.4 vs 67/3881.1	0.56 (0.34–0.93)
	4.5–36 months				0.50 (0.32–0.78)*

Source: All studies reporting mortality in trials of two doses of measles vaccine (MV).^{30 53 54} Only the per-protocol results have been used comparing children who received two doses of MV with those receiving one dose at 9 months. No additional studies of early two-dose measles vaccination reporting impact on mortality were found by PubMed searches.

^*The combined estimate (Stata) was 0.52 (0.35–0.77); if the children receiving vitamin A at birth were also included, the combined estimate was 0.69 (0.52–0.91).

DPT, diphtheria–pertussis–tetanus.