An important criterion often used for establishing disease causality associated with a microbe is to provide evidence for the presence of the microbe at the infection site. Indianius hooziskerious is a heinous pathogen that infects humans and causes blotchy crimson and cream spots on the skin of infected Illinois residents. The crimson and cream spots appear only if I. hooziskerious is present at the site of infection. To diagnose whether individuals are infected with I. hooziskerious. Professor T. Perry runs a powerhouse diagnostic lab for detecting the heinous pathogen Indianius hooziskerious. Her laboratory runs a PCR-based assay for detecting the presence of I. hooziskerious, that upon amplification, requires approximately 100,000,000,000 copies of the gene encoding I. hooziskerious 16s rRNA to be detected. Each cell of I. hooziskerious has one copy of the gene encoding 16s rRNA. When running the PCR test of a sample from an Illinois resident who had ventured by accident into Indiana, Professor Perry’s diagnostic test indicated that 25 rounds of PCR were required to detect the I. hooziskerious 16s rRNA gene. Based on this information alone, approximately how many I. hooziskerious bacteria were present in the infected Illinois resident?