AUG 27, 2018 6:33 PM PDT

Why Some Viruses are so Infectious

WRITTEN BY: Carmen Leitch

Some viruses are highly contagious; noroviruses and rotaviruses need only the right opportunity to strike and they can cause widespread outbreaks inlaces like cruise ships, daycare centers, and nursing homes, for example. New research by scientists at the National Institutes of Health has revealed one reason why they are so effective at spreading infection. This work has shown that these viruses cluster together, exacerbating the severity and spread of disease. It will now help inform the development of treatments that target clusters of viral particles, while current therapeutics are aimed at individual particles.

This is an illustration of membrane-bound vesicles containing clusters of viruses, including rotavirus and norovirus, within the gut. Rotaviruses are shown in the large vesicles, while noroviruses are shown in the smaller vesicles. / Credit: NIH

“This is a really exciting finding in the field of virology because it reveals a mode of virus spread that has not been observed among humans and animals,” said study leader Nihal Altan-Bonnet, Ph.D., senior investigator and head of the Laboratory of Host-Pathogen Dynamics at the National Heart, Lung, and Blood Institute (NHLBI). “We hope that it will provide new clues to fighting a wide range of diseases involving many types of viruses, including those that cause gastrointestinal illnesses, heart inflammation, certain respiratory illnesses, and even the common cold.” 

It had been thought that stomach viruses acted independently until research in 2015 by Altan-Bonnet and colleagues. They found that poliovirus could move in groups, inside of vesicles that contained numerous particles of virus. The phenomenon was compared to a Trojan horse; the vesicles evade detection and enter the body, where the virus is released. 

To learn more about the process, the team looked to rotaviruses and noroviruses, which are usually spread when food contaminated with fecal waste is ingested - called fecal-oral transmission. They looked at the virus in waste, and found it there, not as individual particles but clustered in vesicles, making it ready to infect another host.

“Our findings indicate that vesicle-cloaked viruses are highly virulent units of fecal-oral transmission, and highlight a need for antivirals targeting vesicles and virus clustering,” Altan-Bonnet noted.

These viruses seem to be so infectious because the packets protect the viral particles from degradation, and then they target the host in large groups. The vesicles may also prevent the formation of antibodies that can target the viruses. More work will be necessary to learn more about these viral vesicles, but one thing is certain: hand washing is still an effective way to stop the spread of viral infections.


Sources: NIH, Cell Host & Microbe

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAY 27, 2021
Clinical & Molecular DX
Breakthrough Diagnostic Detects TB Infections in Infants Sooner
MAY 27, 2021
Breakthrough Diagnostic Detects TB Infections in Infants Sooner
There are nearly a million cases of tuberculosis (TB) every year, and over 80 percent of childhood deaths from TB occur ...
MAY 25, 2021
Microbiology
Concern Grows About Emerging H5N8 Flu Virus
MAY 25, 2021
Concern Grows About Emerging H5N8 Flu Virus
Though suspected outbreaks have been documented since 1878, the first confirmed outbreak of bird flu, a highly pathogeni ...
MAY 26, 2021
Genetics & Genomics
Connecting Bacterial Genes to Human Disease
MAY 26, 2021
Connecting Bacterial Genes to Human Disease
This kind of research gets us closer to using fecal samples to get a snapshot of the microbiome, and make disease risk p ...
JUL 11, 2021
Drug Discovery & Development
Antibiotic Resistance May Be Passed Between Dogs and Owners
JUL 11, 2021
Antibiotic Resistance May Be Passed Between Dogs and Owners
Household pets may act as a reservoir for mcr-1, a gene that is resistant to a last-resort antibiotic, colistin. The fin ...
JUL 13, 2021
Immunology
A Moment of COVID, A Lifetime of Immune Protection?
JUL 13, 2021
A Moment of COVID, A Lifetime of Immune Protection?
Does getting vaccinated, or having recovered from COVID, provide life-long protection against the coronavirus? Most like ...
JUL 18, 2021
Microbiology
Alarming Rise in Antibiotic Resistance Among Bangladeshi Kids with Pneumonia
JUL 18, 2021
Alarming Rise in Antibiotic Resistance Among Bangladeshi Kids with Pneumonia
Antibiotic resistance is a growing threat to public health, and experts have been warning about it for so long, they've ...
Loading Comments...