# The influenza virus sentinel surveillance: results of system evaluation in Mozambique, 2016-2021

## TL;DR

This study evaluates how well Mozambique's influenza surveillance system worked from 2016 to 2021, showing it can reliably detect flu cases.

## Contribution

The study provides an evaluation of influenza sentinel surveillance system performance in Mozambique over a five-year period.

## Key findings

- 28.0% of analyzed samples tested positive for influenza.
- The system achieved 69.9% data completeness and 68% consistency.
- The surveillance system showed 77.5% sensitivity in 2017 and 31.4% positive predictive value.

## Abstract

The 2009 influenza pandemic has caused health challenges around the world. Mozambique has faced challenges in implementing surveillance systems, which are obstacles to the timely detection of outbreaks and epidemics. It is intended to evaluate the performance of the influenza sentinel surveillance system between 2016 and 2021. A descriptive-cross-sectional evaluation of the influenza sentinel surveillance system was conducted at the sentinel posts in Maputo. The sample was calculated, and a simple random sampling technique was used to select the 372 patient record forms. Microsoft Excel and Tableau were used for frequency calculations. Based on the Centers for Disease Control - 2001 script, data quality, stability, sensitivity, representativeness, timeliness, and positive predictive value were evaluated. 28.0% (1,305/4,660) of the analyzed samples had positive results, and 56.1% (2,617/4,660) were male. The system obtained data completeness and consistency of 69.9% (3,260/4,660) and 68% (355/372), respectively. It obtained a sensitivity of 77.5% (842/1,086) in 2017, a representative in 98.4% 1,285/1,305 of the neighborhoods, the opportunity of 50.4% (2,349/4,660), and a positive predictive value of 31.4% (410/1,305). The system proved to be useful, providing reliable data on influenza viral circulation. Continuous influenza monitoring would promote prevention interventions in the most vulnerable groups.