Collaborative study to evaluate a working reagent for West Nile virus RNA detection by nucleic acid testing

Area of Science:

• Virology
• Molecular Biology
• Public Health

Background:

• West Nile virus (WNV) poses a significant public health concern.
• Accurate nucleic acid testing (NAT) is crucial for WNV detection.
• Standardized reference materials are needed for reliable WNV NAT assays.

Purpose of the Study:

• To evaluate and quantify a novel reference reagent for West Nile virus (WNV) RNA NAT assays.
• To establish a standardized WNV RNA reference material for inter-laboratory validation.
• To assess the performance of commercial WNV NAT assays using the developed reference reagent.

Main Methods:

• A collaborative study involving 14 laboratories evaluated a WNV RNA reference reagent.
• Participants performed serial dilutions of the reagent and determined RNA endpoints using NAT.
• Maximum likelihood estimation, assuming a Poisson distribution, was used to calculate endpoints.

Main Results:

• The mean titer of the WNV RNA reference reagent was determined to be log 2.52 detectable units/mL (330 units/mL).
• Inter-laboratory variability in WNV RNA detection ranged from log 2.0 to 3.0 units/mL, with two outliers.
• No significant vial-to-vial variation in WNV content was observed in the reference reagent.

Conclusions:

• A validated reference reagent for West Nile virus (WNV) NAT assays has been successfully established.
• The established reagent provides a reliable standard for WNV RNA quantification in diagnostic testing.
• The findings support the use of this reagent for quality control and standardization of WNV NAT assays.