About 32 percent of the Asian monkeys studied had evidence of TB DNA.
The results, said Dr. Gregory Engel, a Seattle physician and epidemiologist for the study, raise questions about inter-species transmission.
The tuberculosis bacteria responsible for most cases of human infection originated about 3 million years ago. TB now affects about 2 billion people in the world.
It's not yet determined whether TB organisms evolved separately in human and non-human primates, or if there were repeated crossovers.
The researchers hope that advances in DNA analysis might reveal the strain of TB present in an individual or a primate population.
The new detection technique for TB DNA in primates also holds promise for better understanding transmission patterns of the disease.
"TB is an exceptionally challenging disease to control," Engel said, "as infected individuals may carry the bacteria in an inactive state, and disease reactivation can occur, especially if the animal is stressed."
A key issue right now among scientists is primate-to-primate spread of TB.
For example, primates that live around humans could conceivably become infected with TB, then come into contact with wild primates, and pass along the pathogen.
This is a particular concern for conservationists trying to prevent the loss of endangered primate species. Zoos and primate centers also strive to prevent the introduction or spread of TB into their colonies for the safety and well-being of the animals, and for the integrity of research which uses primates to study health and disease.
As for human worries about acquiring TB from non-human primates, Engel said, "People are far more likely to acquire TB from other people than they are from monkeys."
Most people living among the macaques or tourists visiting the area do not have the kinds of close face-to face or nose-to-nose interactio
|Contact: Leila Gray|
University of Washington