Featured Research

from universities, journals, and other organizations

Sapronoses: Diseases of another kind, caused by pathogenic microorganisms

Date:
July 23, 2014
Source:
University of California - Santa Barbara
Summary:
The drought that has the entire country in its grip is affecting more than the color of people's lawns. It may also be responsible for the proliferation of a heat-loving amoeba commonly found in warm freshwater bodies, such as lakes, rivers and hot springs, which the drought has made warmer than usual this year. Sapronoses are infectious diseases caused by pathogenic microorganisms that inhabit aquatic ecosystems and/or soil rather than a living host.

Armand Kuris and Kevin Lafferty.
Credit: Sonia Fernandez

The drought that has the entire country in its grip is affecting more than the color of people's lawns. It may also be responsible for the proliferation of a heat-loving amoeba commonly found in warm freshwater bodies, such as lakes, rivers and hot springs, which the drought has made warmer than usual this year.

Related Articles


A 9-year-old Kansas girl recently died of an infection caused by this parasite after swimming in several area lakes. The amoeba enters the body through the nose of an individual and travels to the brain. Nose plugs can lower the odds of this rare but fatal pathogen entering the body.

The amoeba, Naegleria fowleri, is classified as a sapronosis, an infectious disease caused by pathogenic microorganisms that inhabit aquatic ecosystems and/or soil rather than a living host. Scientists at UC Santa Barbara studying infectious disease transmission published their findings in the latest issue of the journal Trends in Parasitology.

"Sapronoses do not follow the rules of infectious diseases that are transmitted from host to host," said lead author Armand Kuris, a professor in UCSB's Department of Ecology, Evolution and Marine Biology (EEMB). "They are categorically distinct from the way we think infectious diseases should operate. The paper tries to bring this group of diseases into sharp focus and get people to think more clearly about them."

A well-known example of a sapronosis is Legionnaires' disease, caused by the bacteria Legionella pneumophila, which can be transmitted by aerosolized water and/or contaminated soil. The bacteria can even live in windshield-wiper fluid. Legionnaires' disease acquired its name in July 1976, when an outbreak of pneumonia occurred among people attending an American Legion convention at the Bellevue-Stratford Hotel in Philadelphia. Of the 182 reported cases, mostly men, 29 died.

A major group of emerging diseases, sapronotic pathogens can exist independently in an environmental reservoir like the cooling tower of the Philadelphia hotel's air conditioning system. Some rely on mosquitoes to find disease hosts for them. Zoonoses, by contrast, require a human host.

According to Kuris, diseases borne by a vector -- a person, animal or microorganism that carries and transmits an infectious pathogen into another living organism -- are more or less virulent depending on how efficiently they are transmitted. As a result, virulence evolves to a level where it is balanced with transmission in order to maximize the spread of the virus. However, Kuris noted that there is no virulence trade-off for sapronotic disease agents. Transmission of a sapronosis pathogen is able to persist regardless of any changes in host abundance or transmission rates.

To quantify the differences between sapronoses and conventional infectious diseases, the researchers developed a mathematical model using population growth rates. Of the 150 randomly selected human pathogens examined in this research, one-third turned out to be sapronotic -- specifically 28.6 percent of the bacteria, 96.8 percent of the fungi and 12.5 percent of the protozoa.

"The fact that almost all of the fungi we looked at are sapronotic is a noteworthy generalization," Kuris said.

"You can't model a sapronosis like valley fever with classic models for infectious diseases," said co-author Kevin Lafferty, adjunct faculty in EEMB and a marine ecologist with the Western Ecological Research Center of the U.S. Geological Survey. "To combat sapronoses, we need new theories and approaches. Our paper is a start in that direction."


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. The original article was written by Julie Cohen. Note: Materials may be edited for content and length.


Journal Reference:

  1. Armand M. Kuris, Kevin D. Lafferty, Susanne H. Sokolow. Sapronosis: a distinctive type of infectious agent. Trends in Parasitology, 2014; DOI: 10.1016/j.pt.2014.06.006

Cite This Page:

University of California - Santa Barbara. "Sapronoses: Diseases of another kind, caused by pathogenic microorganisms." ScienceDaily. ScienceDaily, 23 July 2014. <www.sciencedaily.com/releases/2014/07/140723141822.htm>.
University of California - Santa Barbara. (2014, July 23). Sapronoses: Diseases of another kind, caused by pathogenic microorganisms. ScienceDaily. Retrieved March 1, 2015 from www.sciencedaily.com/releases/2014/07/140723141822.htm
University of California - Santa Barbara. "Sapronoses: Diseases of another kind, caused by pathogenic microorganisms." ScienceDaily. www.sciencedaily.com/releases/2014/07/140723141822.htm (accessed March 1, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Sunday, March 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Reuters - Innovations Video Online (Feb. 27, 2015) A dongle that plugs into a Smartphone mimics a lab-based blood test for HIV and syphilis and can detect the diseases in 15 minutes, say researchers. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Doctor Says Head Transplants Possible Within Two Years

Doctor Says Head Transplants Possible Within Two Years

Buzz60 (Feb. 27, 2015) An Italian doctor is saying he could stick someone&apos;s head onto someone else&apos;s body. Patrick Jones (@Patrick_E_Jones) reports. Video provided by Buzz60
Powered by NewsLook.com
How Your Dentist Could Help Screen You For Diabetes

How Your Dentist Could Help Screen You For Diabetes

Newsy (Feb. 27, 2015) A new study from researchers at New York University suggests dentists could soon use blood samples taken from patients&apos; mouths to test for diabetes. Video provided by Newsy
Powered by NewsLook.com
The Best Tips to Makeover Your Health

The Best Tips to Makeover Your Health

Buzz60 (Feb. 27, 2015) If you&apos;re looking to boost your health this season, there are a few quick and easy steps to prompt you for success. Krystin Goodwin (@Krystingoodwin) has the best tips to give your health a makeover this spring! Video provided by Buzz60
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


Health & Medicine

Mind & Brain

Living & Well

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