can you please tell me how a 2 mth old baby can become infected with streptococcus intermediush . My now 7 yr old son became infected with streptococcus intermedius when he was 2 mth old. He was full term and delivery was normal. He was a healthy birth weight. At 1 day old he received TB vaccine that subsequently became infected. Blood cultures were positive for strep intermedius. He then went on to develope sepsis. I have read that strep intermedius is a bacteria associated with dental work,tattoo, piercings. I was never given a diagnosis but the hospital said it was group b strep. How is this possible?