Featured Research

from universities, journals, and other organizations

Raw sewage: Home to millions of undescribed viruses

Date:
October 3, 2011
Source:
American Society for Microbiology
Summary:
Biologists have described only a few thousand different viruses so far, but a new study reveals a vast world of unseen viral diversity that exists right under our noses. A new article explores ordinary raw sewage and finds that it is home to thousands of novel, undiscovered viruses, some of which could relate to human health.

Biologists have described only a few thousand different viruses so far, but a new study reveals a vast world of unseen viral diversity that exists right under our noses. A paper published on October 4 in the online journal mBio explores ordinary raw sewage and finds that it is home to thousands of novel, undiscovered viruses, some of which could relate to human health.

Viruses are everywhere: every moment of every day, humans are exposed to viruses on surfaces, in foods, and in water. However, our knowledge of the viral universe is limited to a tiny fraction of the viruses that likely exist. There are roughly 1.8 million species of organisms on planet Earth, and each one is host to untold numbers of unique viruses, but only about 3,000 have been identified to date.

To explore this diversity and to better gauge the numbers of unknown viruses that are out there, researchers looked for the genetic signatures of viruses present in raw sewage from North America, Europe, and Africa.

They detected signatures from 234 known viruses that represent 26 different "families," or types, of viruses. This makes raw sewage home to the most diverse array of viruses ever found.

Known viruses included human pathogens like Human papillomavirus and norovirus, which causes stomach flu. Also present were several viruses belonging to those familiar denizens of sewers everywhere: rodents and cockroaches. Bacteria are also present in sewage, so it was not surprising that the viruses that prey on bacteria dominated the known genetic signatures. Finally, a large number of the known viruses found in raw sewage came from plants, probably owing to the fact that humans eat plants and plant viruses outnumber other types of viruses in human stool.

Raw sewage contains more mysteries than answers, however: the vast majority of viral genetic signatures belong to unknown viruses. This fact is significant, says the study's editor, Michael Imperiale of the University of Michigan. Unknown viruses like those found in sewage probably play many roles in human health and environmental processes that we simply do not appreciate yet, he says.

Of the unknown sewage viruses that come from humans, some of them may be opportunists that lie in wait for the human host's immune system to break down and provide an opening, he says.

Other viruses may be benign or even helpful. "There's a theory out there that we may be infected with viruses that don't cause any disease and may have beneficial effects," says Imperiale. There are examples of animal viruses that bear this out, he says, including a herpes virus in mice that makes them somewhat resistant to bacterial infections.

The study's authors plan to follow up their examination of sewage viruses with studies of other environments around the world where viruses are likely to thrive.

Michael Imperiale expects more discoveries to come. "I think this is going to be the tip of the iceberg of how many viruses are out there," he says. "I think the ocean is going to top raw sewage by orders of magnitude," although they won't be found in such densities as they are in sewage, he concedes.


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. P. G. Cantalupo, B. Calgua, G. Zhao, A. Hundesa, A. D. Wier, J. P. Katz, M. Grabe, R. W. Hendrix, R. Girones, D. Wang, J. M. Pipas. Raw Sewage Harbors Diverse Viral Populations. mBio, 2011; 2 (5): e00180-11 DOI: 10.1128/mBio.00180-11

Cite This Page:

American Society for Microbiology. "Raw sewage: Home to millions of undescribed viruses." ScienceDaily. ScienceDaily, 3 October 2011. <www.sciencedaily.com/releases/2011/10/111003180428.htm>.
American Society for Microbiology. (2011, October 3). Raw sewage: Home to millions of undescribed viruses. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2011/10/111003180428.htm
American Society for Microbiology. "Raw sewage: Home to millions of undescribed viruses." ScienceDaily. www.sciencedaily.com/releases/2011/10/111003180428.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. 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:

More Coverage


Sewage Contains the Greatest Diversity of Unidentified Viral Populations Known to Date

Oct. 21, 2011 Raw sewage provides a perfect ecosystem for studying the diversity of viral populations that remain uncharacterized. A pioneering study, which applies metagenomics to the analysis of viral ... read more
from the past week

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