Human parvovirus B19 infection in a Spanish healthcare area: epidemiology, clinical spectrum, and factors associated with hospitalization.

PURPOSE: To describe the epidemiological, clinical, laboratory, and healthcare-related characteristics of human parvovirus B19 (PVB19) infection diagnosed in a Spanish healthcare area during 2019-2024, and to identify factors associated with hospitalization, particularly in adult patients.

METHODS

We performed a retrospective, single-center cohort study in the León healthcare area, Spain, including all hospital-attending patients with microbiologically confirmed acute PVB19 infection diagnosed between January 2019 and December 2024. Acute infection was defined by positive PVB19 IgM and/or PVB19 DNA detection by qualitative PCR in a compatible clinical episode; isolated IgG positivity or incomplete serology without microbiological confirmation was not considered sufficient. Adult and pediatric patients were compared according to clinical manifestations, laboratory findings, and hospitalization status. A multivariate binary logistic regression model was used to identify factors associated with hospitalization in adults.

RESULTS

A total of 81 patients were included, 51 adults (63%) and 30 pediatric patients (37%). Most cases occurred during spring and summer, with a marked rebound after 2020 and a peak in 2024. Fever, arthromyalgias, and cutaneous manifestations were the most frequent clinical findings. Lymphopenia and anemia were the most common laboratory abnormalities. Hospitalization was required in 31 patients (38.3%), more frequently in adults than in children (47.1% vs. 23.3%). In adults, hospitalization was associated with cytopenias and higher C-reactive protein levels. In exploratory adjusted analysis, relevant cytopenia was associated with hospitalization (adjusted OR 7.31, 95% CI 1.07-49.73; p = 0.042).

CONCLUSIONS

PVB19 infection may impose a relevant healthcare burden, particularly in adults. Cytopenias appear to define a more severe hematological phenotype associated with hospitalization and may help identify patients requiring closer clinical monitoring.