Factors associated with hospitalization in the acute phase of Chikungunya.

OBJECTIVE: Determine characteristics associated with hospitalization in the acute phase of Chikungunya. METHODS: Cross-sectional study including data on Chikungunya cases reported in Vitória, Espírito Santo state, Brazil, between March 2016 and December 2021. RESULTS: Hospitalizations accounted for 1.42% (n = 41) of the 2,868 cases included. There were statistically significant differences between hospitalized and non-hospitalized regarding age (P 0.001), which was lower among hospitalized patients, and pregnancy, which was more frequent in the hospitalized group (P 0.010). Patients younger than two years old and older than 65 years corresponded to 31.7% of hospitalizations. Back pain (OR = 0.134; 95% CI = 0.044-0.409) and arthralgia (OR = 0.226; 95% CI = 0.083-0.613) were protective factors for hospitalization. CONCLUSION: Groups at risk of severe Chikungunya, including those under two and over 65 years of age, may require more hospitalization, even with milder manifestations.

Determination of clusters and factors associated with dengue dispersion during the first epidemic related to Dengue virus serotype 4 in Vitória, Brazil.

Dengue occurrence is partially influenced by the immune status of the population. Consequently, the introduction of a new Dengue virus serotype can trigger explosive epidemics in susceptible populations. The determination of clusters in this scenario can help to identify hotspots and understand the disease dispersion regardless of the influence of the population herd immunity. The present study evaluated the pattern and factors associated with dengue dispersion during the first epidemic related to Dengue virus serotype 4 in Vitória, Espírito Santo state, Brazil. Data on 18,861 dengue cases reported in Vitória from September 2012 to June 2013 were included in the study. The analysis of spatial variation in temporal trend was performed to detect clusters that were compared by their respective relative risk, house index, population density, and income in an ecological study. Overall, 11 clusters were detected. The time trend increase of dengue incidence in the overall study population was 636%. The five clusters that showed a lower time trend increase than the overall population presented a higher incidence in the beginning of the epidemic and, compared to the six clusters with higher time trend increase, they presented higher relative risk for their inhabitants to acquire dengue infection (P-value = 0.02) and a lower income (P-value <0.01). House index and population density did not differ between the clusters. Early increase of dengue incidence and higher relative risk for acquiring dengue infection were favored in low-income areas. Preventive actions and improvement of infrastructure in low-income areas should be prioritized in order to diminish the magnitude of dengue dispersion after the introduction of a new serotype.

Serotype influences on dengue severity: a cross-sectional study on 485 confirmed dengue cases in Vitória, Brazil.

BACKGROUND: Dengue is caused by a RNA virus of the family Flaviviridae, which presents four serotypes (DENV-1 to DENV-4) capable of inducing hemorrhage. The purpose of this study was to evaluate the influence of serotype on the outcome of dengue. METHODS: This cross-sectional study included data from dengue cases with serotyping results that occurred between 2009 and 2013 in Vitória, Espírito Santo, Brazil. Data were accessed through the Information System for Notifiable Diseases. Chi-square test, Fisher exact test, Mann-Whitney U test, and logistic regression were performed to assess associations between different serotypes and dengue severity, while considering gender and age. RESULTS: The sample consisted of 485 laboratory confirmed dengue cases, of which 46.4 % were females, with median age of 26 years. Regarding overall samples, 77.3 % were caused by DENV-1, 16.1 % by DENV-4, 6.4 % by DENV-2, and 0.2 % by DENV-3. Severe dengue affected 6.6 % of all cases, of which 32.3 % of the cases caused by DENV-2, 6.4 % of those caused by DENV-4, 4.5 % of those caused by DENV-1, and none of those caused by DENV-3. Severe dengue was found to be seven times more frequent among cases of DENV-2 than among those of the other serotypes. CONCLUSIONS: The present study found that cases of DENV-2 had a higher proportion of severe dengue than among those of DENV-1 and DENV-4. Consequently, early detection of serotypes circulating in the territory could be an important approach to prevent increasing numbers of severe outcomes during dengue outbreaks by predicting the health support needed for early diagnoses and treatment of dengue cases.