A 43-year-old woman checked herself in Massachusetts General Hospital back in 2003 after her trip to Peru. She suffered from fever, enlarged spleen and several other symptoms. After she had had her blood analyzed, she was found a new species of bacterium.

The new bacterium is named after a Brazilian disease investigator Henrique da Rocha Lima, Bartonella rochalimae, and is related to bacteria responsible for trench fever during World War I and cat scratch disease.

Genetic tests and comparisons to DNA archives showed that the woman's bacterium was a new species but the doctors could not determine how the woman contracted the bacterium. They suspected insect bites as she had insect bites on her legs and feet when admitted to the hospital.

The closest bacterium ever isolated was also from Peru back in 2002. Other Bartonella species are transmitted by lice and fleas.

It is still not known whether this particular Bartonella specie could play a role player in human health but researcher suspect there may be more patients with unrecognized infections.
More discoveries are expected related to the human-disease-causing bacteria and viruses owing to the better DNA technology.