Joseph Vinetz, M.D., professor of medicine in UC San Diego’s Division of Infectious Diseases – working in collaboration with colleagues from Universidad Peruana Cayetano Heredia in Lima, Peru, and others – headed the study that led to discovery of the new species in the family of pathogens, Leptospira, which is spread from animals to humans. The findings will be published in the April 1 issue of the Public Library of Science (PLoS) journal Neglected Tropical Diseases.
Leptospirosis is a severe, water-borne disease transmitted from animals to humans, with tens of millions of human cases worldwide each year. Fatality rates can range as high as 20 to 25 percent in some regions, and it is particularly prevalent in tropical countries where poor people live under highly crowded condition, or in rural areas where people are exposed to water contaminated by the urine of Leptospira-infected animals such as rats.
The new species reflects Amazonian biodiversity, according to Vinetz, and the pathogen has apparently evolved to become an important cause of leptospirosis in the Peruvian Amazon region of Iquitos. There, Vinetz leads an international team of physicians from the U.S. and Peru in an NIH-funded training program studying malaria, leptospirosis and other infectious diseases that impact disadvantaged populations in developing countries.
The researchers found that the new species, Leptospira licerasiae – cultured from a very small number of patients, as well as eight rats – is significantly different from other forms of the bacteria at a genomic level and has novel biological features.
“This strain has fundamentally different characteristics,” said Vinetz, adding that the next step is to sequence its genome. “We think that hundreds of patients are infected with this pathogen, which is so unique that antibodies for the disease don’t react to the regular tests for leptospirosis.”
In testing 881 patients in a prospective clinical study of fever, the researchers found that 41 percent of them had antibodies that reacted only to this new strain of the bacteria, showing a much higher incidence of leptospirosis than previously suspected.
“This observation is relevant to other regions of the world where leptospirosis is likely to be common, because it’s necessary to identify the right strain of the Lepstospira in order to make the correct diagnosis,” Vinetz said.
Since isolation of the new Leptospira in people was rare despite the high prevalence of antibodies to this strain of the bacteria in the Amazonian population, Vinetz theorizes that the individuals with positive cultures may have a previously undiscovered immune system defect, making them more susceptible to the disease.
Debra Kain | EurekAlert!
New deep-water coral discovered
22.10.2019 | Smithsonian Tropical Research Institute
DNA-reeling bacteria yield new insight on how superbugs acquire drug-resistance
22.10.2019 | Indiana University
Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.
Quantum physics describes photons as light particles. Achieving an interaction between a single photon and a single atom is a huge challenge due to the tiny...
A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)
It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...
Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.
The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...
Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.
Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...
A new research project at the TH Mittelhessen focusses on the development of a novel light weight design concept for leisure boats and yachts. Professor Stephan Marzi from the THM Institute of Mechanics and Materials collaborates with Krake Catamarane, which is a shipyard located in Apolda, Thuringia.
The project is set up in an international cooperation with Professor Anders Biel from Karlstad University in Sweden and the Swedish company Lamera from...
02.10.2019 | Event News
02.10.2019 | Event News
19.09.2019 | Event News
22.10.2019 | Life Sciences
22.10.2019 | Life Sciences
22.10.2019 | Power and Electrical Engineering