Streptococcus pneumoniae (or pneumococcus) which causes most cases of pneumonia worldwide, secretes a toxin that helps it transport from one person to the next using the hosts’ immune defenses, according to research published online in Cell Host & Microbe.

The study explains survival “strategies” used by the bacteria Streptococcus pneumoniae, or pneumococcus, which causes millions of infections each year. Most often infecting the nasal cavity, sinuses and lungs, these infections can be deadly in patients with weak immune systems, especially young children and the elderly.

By emitting the pneumolysin toxin, S. pneumoniae “gets creative” in both finding nutrients and exiting its current host, say the study authors. The toxin evokes a strong response from the body, they say, because it is destructive, drilling holes (pores) into cells to get at the nutrients inside them. Thus, the toxin gets the bacteria food to hold them over while outside the body, and then, by triggering secretions, ensures that they exit a body that is assaulting them with inflammatory, immune responses. This helps them to quickly find a new and more hospitable host.