Run clamAV.cs

// ##### RUN AV ON FILE #####
log.LogInformation("Download completed. Connecting to AV server {ClamAVServerUrl}:{ClamAVServerPort}... ", ClamAVServerUrl, ClamAVServerPort);
var clam = new ClamClient(ClamAVServerUrl, ClamAVServerPort);

bool isConnected = await clam.PingAsync();
var version = await clam.GetVersionAsync();
if (!isConnected) throw new Exception("AV server connection could not be established.");

log.LogInformation("Connection ok: {IsConnected}. AV server reports version: {ServerVersion}", isConnected, version);

var scanResult = await clam.SendAndScanFileAsync(ms.ToArray());

switch (scanResult.Result)
{
    case ClamScanResults.Clean:
        log.LogInformation("The file is clean!");
        // Continue
        break;
    case ClamScanResults.VirusDetected:
        log.LogCritical("Virus found. Deleting file.");
        await blobClient.DeleteIfExistsAsync(Azure.Storage.Blobs.Models.DeleteSnapshotsOption.IncludeSnapshots);
        // Do other steps
        break;
    case ClamScanResults.Error:
    default:
        log.LogInformation("File scan error occurred. {ScanResult}", scanResult.RawResult);
        break;
}

I have linked this discussion in my post to the part where these settings were discussed and improved that bit slightly. Thanks @TimothyODonnell