Figure 4 shows that when isolated S. pneumoniae genomic DNA was used as the template, a clear positive signal appeared on the test line, however no bands showed on the test line when genomic DNA from any other common respiratory infection was used as the template. These results indicated that the RPA-LFS assay system established here was highly specific for S. pneumoniae and does not cross-react with other pathogens. Here, RPA1 is linked to respiratory tract infectious disorder.