Caracterização clínico-laboratorial dos casos de dengue e Zika em uma coorte em Goiânia, Goiás, Brasil, 2015-2019

Abstract

Introduction: dengue is the most important arbovirus in the world due to its morbidity and mortality burden and is hyperendemic/epidemic in Brazil. Zika virus is present in tropical and subtropical countries and, in 2016, there was a worrying Brazilian epidemic. The co-circulation of dengue and Zika viruses, because they are similar, makes diagnosis and treatment a challenge for health services. Objectives: to present the strategies of conducting a cohort in the city of Goiania, Goias; present the seasonality of febrile conditions evaluated and characterize the patterns of clinical and laboratory presentation of confirmed cases of dengue and Zika and of coinfection of these arboviruses. Methods: a prospective cohort was carried out between 2015 and 2019. Fever was monitored weekly by phone calls and by direct contact with the attending physician. IgG anti-dengue antibodies were used for an initial survey and other annual surveys. Testing of NS1 antigen, IgM anti-dengue antibodies and neutralizing antibodies by the plaque reduction neutralization test, and the viral genome by RT-PCR were the confirmatory tests for acute dengue infection. RT-PCR was used for diagnostic confirmation of Zika virus infections. Results: A partnership between the academy and public health services was adopted and the participation of Family Health Teams was essential for the proper conduct of the study. In return, the researchers benefited the Health Services through surveillance and health care activities. Acute respiratory infections (ARI) represented 53.0% and pneumonia 1.7% of the total of 1268 febrile cases, both of which were more frequent in the fall. Acute diarrheal disease (ADI) represented 8.7% of the total and was more frequent in the summer. Dengue and Zika represented, respectively, 11.6% and 6.1% of all cases and predominated in rainy months. 206 dengue cases were confirmed in this study. 80.6% presented and 19.4% did not present clinical criteria that met the definition of a suspected case. The rash was present in 45.9% of 37 confirmed cases of Zika. Leukopenia and absence of thrombocytopenia predominated in dengue and Zika cases. The positive predictive values for the clinical suspicion of dengue and Zika were 85.8% and 16.5%, respectively. Six cases of dengue/Zika co-infection were confirmed. Five of them had symptoms compatible xv with suspected Zika and one of dengue. Among cases of co-infection, leukopenia and normal platelets predominated. Conclusions: The interinstitutional partnership between academia and Health Services was successful, with benefits for both institutions. Previous descriptions of the seasonal profile of ARI, pneumonia, dengue and Zika were in agreement with the results of this research. The symptoms of individuals infected by the dengue and Zika viruses may not meet the criteria for suspected cases of these arboviruses and cases of dengue/Zika coinfection may meet the criteria for suspicion of both, which favors mistakes in the clinical diagnosis. In areas of co-circulation of these viruses, the use of specific laboratory tests is important to prevent and treat adequately these diseases.