Epidemiology of pertussis in Tunisia; results of five years 2013-2017

Abstract

Abstract Background Pertussis or whooping cough, is a highly contagious respiratory disease caused by a bacteria gram negative mainly Bordetella pertussis. It is globally endemic despite a high vaccination coverage. In 2014, the World Health Organization estimated the total number of affected persons to 16 million and the number of child deaths reached 190 000. Since 2012, many countries have experienced a resurgence of pertussis including Tunisia. Our objective was to describe the epidemiological situation of pertussis in Tunisia from 2013 to 2017. Methods Our study was a retrospective descriptive study based on data of the surveillance system of Mandatory Reporting Diseases in Tunisia from 2013 to 2017. Data were collected using the declaration standardized forms which included in addition to the socio-demographic data, information regarding vaccination status, date of onset of symptoms and laboratory results (culture and PCR). Data entry was using EpiData and data analysis using SPSS-20. Results During the study period, a total of 252 cases were notified. Males were more affected (55.1%). Age was in average 89 days (3 months). Almost the third were hospitalized in Intensive Care Unit (32.2%). Most cases were reported during 2013 and 2014 (35.7% et 55.5% respectively) and the lethality rate reached 7.2% in 2014. Half cases were notified in the Grand Tunis region. PCR was positive in 74.1% of the cases and bacterial culture was positive in 14.3%, isolating Bortedella pertussis. Vaccination status was mentioned in 70.5% of the cases: it was up-to-date in only 35.7% of the cases and incomplete in 9.8% of the cases. Conclusions Our results showed that pertussis has known a considerable increase the last years, especially in 2013 and 2014. This prompts us to be more vigilant regarding this disease, which has been neglected the last decades. Education of population as well as health professionals is extremely important, particularly the importance of vaccination and preventive measures. Key messages From 2013 to 2017, number of pertussis cases in Tunisia varied with a considerable increase in 2013 and 2014. With the increase of pertussis cases and severity, preventive measures should be taken especially the importance of vaccination.