Facilitating Cross-border Viral Sequencing Through Nucleic Acid Sample Transport Using Dry Cards

Area of Science:

• Virology
• Genomics
• Public Health

Background:

• Developing countries often lack advanced sequencing infrastructure for infectious disease surveillance.
• A novel nucleic acid sample transportation method is needed for virus genomic sequencing in resource-limited areas.

Purpose of the Study:

• To evaluate the efficacy of Flinders Technology Associates (FTA) cards for transporting amplified whole-genome DNA of SARS-CoV-2.
• To assess the feasibility of virus genomic sequencing from samples transported using FTA cards in resource-limited settings.

Main Methods:

• 120 SARS-CoV-2 positive nasopharyngeal swab samples were collected in Sierra Leone.
• Nucleic acid extraction and whole-genome amplification were performed locally.
• Amplified DNA was applied to FTA Elute cards for room temperature shipment and subsequent elution and sequencing.

Main Results:

• The FTA card method demonstrated a 9.6% amplicon recovery rate, sufficient for viral genome sequencing.
• 86 (71.7%) high-quality SARS-CoV-2 genomic sequences were obtained, with most exceeding 100X depth.
• Co-circulation of Delta, Omicron, and B.1 lineages was identified; samples with Ct ≤ 27 yielded effective sequences (73.6%).

Conclusions:

• Transportation of amplified nucleic acid samples on FTA cards facilitates virus genomic sequencing in resource-limited regions.
• This approach can enhance local virus surveillance and outbreak response.
• Further optimization may improve sequence recovery rates, increasing sequencing accessibility in underdeveloped areas.