Affiliation:
1. Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani (IRCCS), 00149 Rome, Italy
2. Scientific Direction, National Institute for Infectious Diseases Lazzaro Spallanzani (IRCCS), 00149 Rome, Italy
Abstract
The definitive diagnosis of the Rift Valley fever virus (RVFV) requires a form of testing that is available only in reference laboratories. It includes indirect immunofluorescence assay (IFA), the serum neutralization assay (NA), and real-time PCR. Therefore, often, no attempts are made to detect it, even among travelers from endemic areas. In this study, the presence of anti-RVFV IgG and IgM was retrospectively screened in stored serum samples from people who were admitted with arbovirus symptoms at the National Institute for Infectious Diseases (INMI) L. Spallanzani, Rome, Italy. Overall, 80 residual serum samples were anonymized, and sub-aliquots were prepared and tested for anti-RVFV IgG and IgM. A serum neutralization assay was used as a confirmatory test. There was a positive result in eight out of 80 samples (10%) for anti-RVFV IgG, with titers ranging from 1:40 up to 1:1280. Three of eight (2.6%) samples were confirmed as seropositive through an in-house serum neutralization assay, with antibody titers ranging from 1:10 to 1:160. All samples resulted negative for anti-RVFV IgM and RVFV RNA when tested by IFA and real-time RT-PCR, respectively. Our data highlight that several RVFV infections can possibly escape routine virological diagnosis, which suggests RVFV testing should be set up in order to monitor virus prevalence.
Funder
European Project SHARP JA
Italian Ministry of Health
Subject
Virology,Microbiology (medical),Microbiology
Reference30 articles.
1. Scoping future outbreaks: A scoping review on the outbreak prediction of the WHO Blueprint list of priority diseases;Jonkmans;BMJ Glob. Health,2021
2. (2023, July 12). European Centre for Disease Prevention and Control Home Page. Facts about Rift Valley Fever. Available online: https://www.ecdc.europa.eu/en/rift-valley-fever/facts.
3. Rift Valley fever virus: A review of diagnosis and vaccination, and implications for emergence in Europe;Mansfield;Vaccine,2015
4. World Health Organization (2023, July 05). Efficacy Trials of Rift Valley Fever Vaccines and Therapeutics Guidance on Clinical Trial Design. Meeting Report. Available online: https://cdn.who.int/media/docs/default-source/blue-print/rift-valley-fever-blueprint-trial-design-meeting-report-2019.pdf?sfvrsn=ee74e0fb_3.
5. Rift Valley fever: Biology and epidemiology;Wright;J. Gen. Virol.,2019