The role of surveillance in a 'high risk' approach to the elimination of neonatal tetanus in Egypt

Abstract

Background: Despite an international resolution to eliminate neonatal tetanus (NT) as a public health problem by the year 1995, 490000 cases occurred worldwide in 1994. An analysis of the NT elimination programme in Egypt was conducted to determine the utility of a 'high risk' approach in controlling this disease.

Methods: Three of the indicators for identifying districts at high risk of NT were evaluated. NT rates, tetanus toxoid coverage (TT2+), and urban or rural status. The reduction in NT incidence from 1992 to 1994 was compared between those high risk districts (> or = 1 NT case/1000 live births in 1992) which did or did not conduct supplementary immunization (P = 0.035).

Results: In a multivariate analysis, the strongest indicator of the NT risk in a district was the presence of > or = 1 case/1000 live births in the previous year (Rate ratios [RR] = 3.34 in 1993 and 3.07 in 1994, P < 0.001). The TT2+ coverage was not a reliable indicator of NT risk. Urban areas had a significantly lower risk than rural areas (RR = 0.62) in 1993 and 0.49 in 1994, P < 0.001). The decline in NT rates was greatest in the 'high risk' districts that conducted supplementary immunization in both 1993 and 1994.

Conclusions: Although tetanus toxoid immunization of pregnant women will protect newborns from NT, TT2+ coverage calculated by the administrative method may not reflect a population's risk of NT. Surveillance data, however, can be used to identify areas where the ongoing risk NT is high. Conducting supplementary immunization in areas that are identified as 'high risk' on the basis of previous NT rates can significantly reduce the number of cases in subsequent years.