One of the challenges in managing patients with hantavirus infection is accurately identifying individuals who are at risk of developing severe disease. Prompt identification of these patients can facilitate critical decisions, such as early referral to an intensive care unit. The identified prognostic factors could be of utility in guiding medical care to enhance the management of hantavirus infection.

To identify and evaluate prognostic factors associated with mortality in hantavirus infection.

We conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses-reported systematic review following Cochrane guidance adapted for prognosis. We searched PubMed/MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Biblioteca Virtual de Saúde or Lilac and EMBASE, from 1 January 1993 to 2 October 2025. We included studies evaluating individual prognostic factors or risk assessment models of New World hantavirus infections, with no restrictions on study design, publication status or language. When feasible, we conducted meta-analyses for prognostic factors using the inverse variance-based method with random effect model. We assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach.

We included 25 studies with a total of 7284 participants. We identified the following prognostic factors for which we found moderate to high certainty that are associated with increased mortality: age over 18 years, female sex, rural residence, elevated creatinine levels, increased haematocrit, signs of bleeding and the presence of infiltrates on chest radiographs.

Our systematic review identified prognostic factors for mortality in patients with New World hantavirus infection. These factors can inform clinicians in making more informed management decisions. Furthermore, our findings lay the groundwork for the future development of a clinical prognostic model, potentially enhancing patient care and outcomes.

CRD42021225823.