Chronic and reactivated dengue infection in an immunocompromised host: insights from a case report

Abstract

Background: Dengue, a viral infection transmitted by mosquitoes, is a growing global health concern, particularly as its spread now puts half of the world's population at risk. While dengue usually resolves after the primary infection, persistent or chronic cases can occur in immunocompromised individuals.

Case presentation: This case study reports a 43-year-old woman with lupus nephritis and end-stage kidney disease who experienced symptomatic dengue reactivation nearly three years after her initial infection. Despite low viral loads, dengue RNA was detectable in her blood multiple times between 32 and 34 months after the initial detection. Genomic analysis confirmed that the same DENV-1 strain persisted, suggesting chronic infection rather than reinfection. The patient's immunosuppressive treatments, including rituximab, likely impaired her immune response to the initial infection, contributing to viral persistence. Additionally, her profound immunosuppressive state at the time of reactivation, potentially exacerbated by coinfections, may have triggered the virus to re-emerge.

Conclusion: This case highlights the rare but clinically relevant possibility of chronic dengue infection in immunocompromised patients. The confirmed persistence of the same viral strain over nearly three years challenges the conventional view of dengue as a strictly acute infection. It raises concern about the potential for reintroduction and re-emergence of previously circulating strains, as well as the detrimental tissue consequences of chronic infection by the virus. These findings have important implications for clinical management, diagnostic strategies, and public health surveillance, and underscore the need for further research to better understand the mechanisms of dengue chronicity-particularly those involving viral immune evasion and host immune dysfunction.

Keywords: Case report; Chronic; Dengue virus; Immunocompromised; Reactivation.

Fig. 1

Biological characteristics of the patient from 2020 to 2024. A Timeline illustrating the patient’s disease progression, including detection of plasma DENV, nasopharyngeal SARS-CoV-2, and whole-blood CMV by RT-PCR. B Levels of anti-DENV IgG measured by ELISA. C Levels of anti-SARS-CoV-2 IgG measured by ELISA. D Gamma globulin concentrations assessed by protein electrophoresis. E Lymphocyte counts measured over this period. (F) Platelet concentrations recorded during the same timeframe. G Hemoglobin levels assessed throughout this period

Fig. 2

Comparison of DENV sequences from this clinical case. A Summary of DENV serotypes detected on Reunion Island from 2020 to 2024 (as of July 2024) as determined by RT-PCR. B Phylogenetic relationships of DENV-1 genotype I sequences from this case, including a sequence from the sample collected on 18/05/2020 and a sequence from the sample collected on 14/02/2023, which had the best coverage and quality. These sequences were compared with other genotype I sequences from 2019 to 2022 detected on Réunion Island, as previously described by Frumence et al. 2024 [4]. The phylogenetic tree was generated via a maximum likelihood (ML) approach with MAFFT alignment and IQ-TREE software with the best-fitting model and 1,000 ultrafast bootstrap replicates