Molecular Detection of Orthohantavirus puumalaense in Plasma and Urine Samples from Hospitalized Patients Presenting with a Serologically Confirmed Acute Hantavirus Infection in France

Molecular detection of Orthohantavirus puumalaense (PUUV) RNA during the course of the disease has been studied in blood of patients in Sweden and Slovenia. The use of urine has been poorly investigated. The aims of this work were to study PUUV RNA detection in plasma from a cohort of patients in France where a different PUUV lineage circulates and to assess the use of urine instead of plasma. Matched plasma and urine samples were collected daily from hospitalized patients presenting with fever, pain, and thrombocytopenia within the last 8 days and testing positive for IgM and IgG against PUUV in serum collected at inclusion and/or approximately 1 month after release. RNA was extracted from samples, and PUUV RNA was detected using real-time reverse transcription-PCR for plasma and urine samples. Sixty-seven patients presented a serologically confirmed acute hantavirus infection. At inclusion, PUUV RNA was detected in plasma from 55 of 62 patients (88.7%) sampled within the first week after disease onset, whereas it was detected in 15 of 60 (25.0%) of matched urine samples. It was then detected from 33 (71.7%) and 2 (4.4%) of 46 patients discharged from the hospital during the second week after disease onset, in plasma and urine, respectively. When PUUV RNA was detected in urine it was also detected in plasma, and not vice versa. Detection of PUUV RNA in plasma from hospitalized patients in France is similar to that observed in Sweden and Slovenia. Urine is not an appropriate sample for this detection.

Seroprevalence of Hantavirus in Forestry Workers, Northern France, 2019-2020

We aimed to estimate the seroprevalence of Puumala orthohantavirus (PUUV) among forestry workers in northern France, and to explore sociodemographic risk factors. We conducted a random cross-sectional seroprevalence survey among 1777 forestry workers in 2019-2020. The presence of immunoglobulin G against PUUV antigens in serum was assessed using enzyme-linked immunosorbent assay and confirmed using immunofluorescence assay. Poisson regression models were used to explore factors associated with seropositivity. Weighted seroprevalence was 5% (3-6) in northeastern France, 4% (2-6) in north central France, and 1% in two regions located in the center of the country (Auvergne and Limousin). There were no seropositive workers detected in northwestern France. Seropositivity was associated with age, sex, and cumulative seniority in the forestry sector. Seroprevalence was highest in known endemic areas of the northeast and lowest in the northwest. Nevertheless, we found serological evidence of PUUV infection in two regions located in the center of the country, suggesting circulation of the virus in these regions, previously thought to be non-endemic.