External quality assessment of Rift Valley fever diagnosis in countries at risk of the disease: African, Indian Ocean and Middle-East regions

Abstract

Rift Valley fever virus (RVFV), an arbovirus belonging to the Phlebovirus genus of the Phenuiviridae family, causes the zoonotic and mosquito-borne RVF. The virus, which primarily affects livestock (ruminants and camels) and humans, is at the origin of recent major outbreaks across the African continent (Mauritania, Libya, Sudan), and in the South-Western Indian Ocean (SWIO) islands (Mayotte). In order to be better prepared for upcoming outbreaks, to predict its introduction in RVFV unscathed countries, and to run efficient surveillance programmes, the priority is harmonising and improving the diagnostic capacity of endemic countries and/or countries considered to be at risk of RVF. A serological inter-laboratory proficiency test (PT) was implemented to assess the capacity of veterinary laboratories to detect antibodies against RVFV. A total of 18 laboratories in 13 countries in the Middle East, North Africa, South Africa, and the Indian Ocean participated in the initiative. Two commercial kits and two in-house serological assays for the detection of RVFV specific IgG antibodies were tested. Sixteen of the 18 participating laboratories (88.9%) used commercial kits, the analytical performance of test sensitivity and specificity based on the seroneutralisation test considered as the reference was 100%. The results obtained by the laboratories which used the in-house assay were correct in only one of the two criteria (either sensitivity or specificity). In conclusion, most of the laboratories performed well in detecting RVFV specific IgG antibodies and can therefore be considered to be prepared. Three laboratories in three countries need to improve their detection capacities. Our study demonstrates the importance of conducting regular proficiency tests to evaluate the level of preparedness of countries and of building a network of competent laboratories in terms of laboratory diagnosis to better face future emerging diseases in emergency conditions.

The Emergence of Rift Valley Fever in Gedaref State Urges the Need for a Cross-Border One Health Strategy and Enforcement of the International Health Regulations

“…Due to its threat to public health and the high risk of epidemics, the WHO identifies RVFV as a priority pathogen for its research and development blueprint [ 23 ]. Therefore, improving RVF diagnostic capacity in endemic countries and countries at risk of epidemic emergence is crucial to prevent further emergence and help in responding to outbreaks [ 22 , 24 ].…”

Fièvre de la vallée du Rift en Tunisie : Synthèse sur la situation actuelle et perspectives

“…Tunisian laboratories have also participated in several 'external quality assessment' tests for RVF diagnosis. These trials certainly reinforced capacity building and improved RVF diagnosis capacities of involved Tunisian laboratories (Monaco et al, 2015;Pedarrieu et al, 2021).…”

Overview of Rift Valley Fever

“…This involves developing more sensitive and specific diagnostic tests, including rapid and point-of-care tools. Integrating surveillance data with advanced modeling techniques can improve prediction and forecasting capabilities (Aurélie et al 2021).…”