A close cousin of the bacterium that debilitated thousands of World War I soldiers has been isolated at UCSF from a patient who had been on an international vacation. The woman, who has since recovered, suffered from symptoms similar to malaria or typhoid fever, two infections that can occur in returning travelers.
But genetic detective work revealed that she was infected with a new bacterium that had never before been isolated from a human.
A UCSF infectious disease team, in collaboration with colleagues from other institutions, found that the new microbe is genetically similar to one spread by body lice in the trenches during World War I. That bacterium, called Bartonella quintana, caused a disease known as trench fever, and debilitated tens of thousands of soldiers with severe leg and back pain and recurrent fevers.
The new species, recently named Bartonella rochalimae, is also closely related to the bacterium identified about 10 years ago as the cause of cat scratch disease: Bartonella henselae, which infects more than 25,000 people a year in the U.S.
The discovery is reported in the June 7 issue of The New England Journal of Medicine.
The woman had been traveling in the Peruvian Andes. She suffered from potentially life-threatening anemia, an enlarged spleen and a high fever for several weeks, as do victims of malaria and typhoid. The Andes are also home to another Bartonella species, spread by sand flies. The researchers first thought this was causing the patients infection.
But genetic comparisons showed that although the new bacterium is related enough to be classified with the other Bartonella bacteria, it is nevertheless distinct from all of them, the UCSF team found. The UCSF lab is one of the few in the world able to isolate and grow human Bartonella species, and culture of the new organism made study of the DNA much easier.