Analysis of epidemiology of acute flaccid paralysis and polio vaccination coverage in the northeast region of Brazil from 2015 to 2019

*Correspondence: [e-mail].

Abstract

Background: Acute flaccid paralysis or poliomyelitis is an acute infectious viral disease, prevalent at any age, of compulsory notification in Brazil. In its most severe form, it develops motor deficits that cause paralysis, especially in the lower limbs. Among the preventive actions are the immunizations, Inactivated Poliomyelitis Vaccine (IPV) and Oral Poliomyelitis Vaccine (OPV), with coverage ≥ 95%. However, in recent years a drop in vaccination coverage has been observed, mainly due to misinformation, leading to an increase in the number of cases of the disease.

Objective: To estimate the number of reported cases of acute flaccid paralysis and the proportion of vaccination coverage in the Northeast region of Brazil, from 2015 to 2019.

Methods: This is a descriptive study based on notification data of cases of acute flaccid paralysis available in the Notifiable Diseases Information System (SINAN), for the period from 2015 to 2019. To evaluate the vaccination coverage for poliomyelitis in the same period, data from the National Immunization Program Information System (SI-PNI) were used. All data refer to the Northeast region of Brazil.

Results: Between January 2015 and December 2019, 956 cases of acute flaccid paralysis were reported in the Northeast region, noting an increase of 8.6% between 2015 (186 cases) and 2019 (202). The only states that did not record an increase from the first to the last year analyzed were Alagoas (-23.08%), Pernambuco (-16.13%) and Bahia (-8.57%), however, the same states show a tendency to increase the number of cases after a decrease in 2016. As for vaccination coverage, there was a 17.63% drop in IPV coverage and 17.72% in its booster (OPV), throughout the period. In 2019, no state reached the stipulated coverage of 95%, to the detriment of 2015, when all states, with the exception of Piauí, Alagoas and Sergipe, had adequate coverage for polio; only the states of Ceará and Pernambuco achieved the coverage target for polio booster in the analyzed period.

Conclusion: The analysis of the collected data reveals an increase in cases of acute flaccid paralysis in the Northeast region of Brazil between 2015 and 2019, along with a decrease in vaccination coverage for polio (IPV) and its booster (OPV). Such changes alert to the risk of reintroduction of poliovirus circulation in our country, which was considered eradicated in the Americas in 1994 by PAHO (Pan American Health Organization).

Publication History

Article published online:
12 May 2025