The MBTA has dunned Penelope the Snake's owner $650 for sanitizing the Red Line car she spent a month in.

In a letter to Melissa Moorhouse of Allston, MBTA treasurer-collector Wesley Wallace writes that letting the snake loose, even if inadvertently, violates the T's pet policy and adds:

To rid the subway car of any traces of germs such as salmonella, which may have been left by your snake, MBTA maintenance crews had to scrub and disinfect the Red Line car in which your snake was found. The MBTA took this necessary action based on information from the Center for Disease Control and Prevention, which states, "Children under five years old and people with weak immune systems should avoid contact with reptiles and any items that have been in contact with reptiles and amphibians.

Complete letter.

Chris Tashjian wonders:

So, the MBTA only scrubs and disinfects trains when a snake is found on board? Gross

Kate Hutchinson wonders if this means the T will start dunning people who cough and sneeze on train poles during flu season.

Jamie Doherty adds: