Background: Data on trends in malaria prevalence is significant to assist efforts in the control and prevention of the disease. This retrospective study was, therefore, aimed to determine the prevalence of malaria in Woreta town, northwestern Ethiopia over 8 years.

Methods: A retrospective study was conducted in Woreta town, northwestern Ethiopia, from November to January 2013. Eight years (2005 to 2012) health center record of malaria cases was reviewed. Odds ratio (OR) was used to determine trend in malaria prevalence with respect to age, sex and Plasmodium species. P-values less than 0.05 were considered to be statistically significant.

Results: From 2005 to 2012, a total of 102,520 suspected cases of malaria were reported at Woreta health center. Of these, 33,431 (32.6%) were microscopically confirmed to be positive for the disease. Among these positive cases, 17,700 (52.9%) and 15,731 (47.1%) were males and females, respectively. Children less than 5 years old were 1.3 times more likely to be infected by malaria than those with 5-15 years ([OR]; 1.3, 95% confidence interval [CI]; 1.26-1.34, p < 0.001). There was higher percentage (69.7%) of Plasmodium falciparum infection than Plasmodium vivax (26.5%); and the difference was statistically significant (p < 0.05). There was fluctuation in yearly malaria prevalence with a minimum of 7% in 2008 and maximum of 47% in 2005.

Conclusions: The present study revealed that malaria continued to be one of the major public health problems in Woreta town, northwest Ethiopia. Moreover, there was no successive yearly reduction in its prevalence. Therefore, efforts are required to reduce the disease burden through continuous monitoring and evaluation of control measures in the study area.

Ethical clearance was obtained from Research Ethical Review Committee of Microbial Cellular and Molecular Biology Department, Addis Ababa University. The purpose and objective of the study was explained to administrative and health officials of the study area. Confidentiality issues of study participants were kept.

Not applicable.

The authors declare that they have no any competing interests.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Fig. 1

Fig. 1

Annual trend of malaria prevalence...

Fig. 1

Annual trend of malaria prevalence at Woreta town, Northwest Ethiopia (2005–2012)

Fig. 2

Fig. 2

Trend of malaria cases by...

Fig. 2

Trend of malaria cases by year and malaria species at Woreta town, Northwest...

Fig. 3

Fig. 3

An eight years (2005–2012) average...

Fig. 3

An eight years (2005–2012) average seasonal distribution of malaria cases at Woreta town,...