Featured Research

from universities, journals, and other organizations

Why some strains of Lyme disease bacteria are common and others are not

Date:
December 4, 2012
Source:
American Society for Microbiology
Summary:
New clues about the bacteria that cause Lyme disease could lead to a novel strategy to reduce infections, according to new research. The study reveals that the immune system of the white-footed mouse, a very common reservoir for the bacteria that causes the disease responds differently to different strains of the bacterium, a finding that will help scientists tweak the animals' immune systems to prevent spread of infection.

New clues about the bacteria that cause Lyme disease could lead to a novel strategy to reduce infections, according to a study to be published in mBio, the online open-access journal of the American Society for Microbiology, on Dec. 4.

Related Articles


The study reveals that the immune system of the white-footed mouse, a very common reservoir for Borrelia burgdorferi (the bacterium that causes the disease), responds differently to different strains of the bacterium, a finding that will help scientists tweak the animals' immune systems to prevent infection. A vaccine that keeps these wild mice free of the pathogen could significantly curb the spread of the disease from mice to ticks to humans.

"There's no human vaccine, and there's not likely to be one," says Alan Barbour of the University of California, Irvine, the lead author of the study. "We have to focus on lowering the risk. One way to do that is by treating the animals that carry the disease." Rabies offers a good example of how this might be accomplished, says Barbour. By deploying vaccine-laced food bait, public health officials have managed to lower the rabies infection rate in wildlife and significantly limited the spread of the disease to pets and humans.

Although Lyme disease only emerged in the U.S. in the past 40 years or so, around 25,000 cases are now reported every year in this country and the medical costs of these cases are estimated to range in the billions of dollars. Despite the growing importance of the disease, little is known about the evolution and ecology of the bacterium that causes the illness.

Barbour and his colleagues sought to understand why as many as 15 different strains of B. burgdorferi exist in the wild at differing degrees of prevalence. In the parts of the country where Lyme disease is most common, the majority of white-footed mice are infected with B. burgdorferi during the course of the year. Unlike humans and lab mice, white-footed mice don't get sick when they're infected so the bacteria grow and multiply within them, and when a deer tick bites it sucks up the bacteria along with its blood meal.

In the lab, the group at UC Irvine exposed white-footed mice to various strains of B. burgdorferi and tracked the course of the infection. All the B. burgdorferi strains infected the white-footed mice, but some strains managed to grow to high densities in various mouse tissues while others did not.

Barbour says the immune reactions the mice mounted against the various strains explain these discrepancies: the greater the immune response, the fewer bacteria found in a mouse's tissues and vice-versa. Importantly, thestrains that grew to greatest densities within the mice are also the strains that are most prevalent in the wild.

When they looked at the immune reaction to individual B. burgdorferi proteins the authors found a complex interplay of reactivities. The mice reacted in different degrees to the various proteins present in a single bacterial strain, which could explain why such a great diversity of B. burgdorferi strains are sustained in the wild, say the authors.

Barbour says knowing more about how the white-footed mouse reacts to all the various B. burgdorferi strains and immunogenic proteins will help vaccine developers select the best proteins to put in a vaccine. "The best candidate for the mouse vaccine is something that's the same in all the [B. burgdorferi] strains," he says.

Once a vaccine for the white-footed mouse is developed, it will need to be tested by exposing immunized mice to a selected set of diverse B. burgdorferi strains, says Barbour, and the results of this study can help make that selection. "If we can find five that are representative, that would be an advantage."

This study, he says, "is going to provide a foundation for future studies in understanding the infection in these animals as we proceed with developing vaccines."


Story Source:

The above story is based on materials provided by American Society for Microbiology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Elisabeth Baum, Fong Hue, and Alan G. Barbour. Experimental Infections of the Reservoir Species Peromyscus leucopus with Diverse Strains of Borrelia burgdorferi, a Lyme Disease Agent. mBio, 2012; DOI: 10.1128/mBio.00434-12

Cite This Page:

American Society for Microbiology. "Why some strains of Lyme disease bacteria are common and others are not." ScienceDaily. ScienceDaily, 4 December 2012. <www.sciencedaily.com/releases/2012/12/121204081318.htm>.
American Society for Microbiology. (2012, December 4). Why some strains of Lyme disease bacteria are common and others are not. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2012/12/121204081318.htm
American Society for Microbiology. "Why some strains of Lyme disease bacteria are common and others are not." ScienceDaily. www.sciencedaily.com/releases/2012/12/121204081318.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins