AUG 12, 2019 6:51 PM PDT

Researchers Find That Rift Valley Fever Can Spread in US Livestock

WRITTEN BY: Carmen Leitch

We live in a globally connected world where it’s easy to travel virtually anywhere at the drop of a hat. It’s also a world in which there are still many ongoing conflicts and many places with poor infrastructure. Those factors have helped diseases emerge and spread. With that in mind, Colorado State University researchers wanted to know more about how Rift Valley Fever might impact livestock if it arrives in the US.

Daniel Hartman, lead author of the study and a graduate student pursuing a doctoral degree in microbiology, collecting mosquitoes in Fort Collins, Colorado. / Credit: Kellen Bakovich/Colorado State University

Mosquitoes carry and spread the virus that causes Rift Valley Fever, which is usually seen in cattle but can infect people. It has caused several serious outbreaks in African countries. Often people have no symptoms when they’re infected but it can cause ocular disease, encephalitis, and hemorrhagic fever in about ten percent of infected people. Countries in the Middle East and Africa have experienced outbreaks since the year 200; in nearly all of those outbreaks there were deaths.

Reporting in Transboundary and Emerging Diseases, the researchers found that local mosquitoes that live in near Colorado feedlots, Culex tarsalis mosquitoes that can already carry West Nile virus, could also carry Rift Valley Fever. The mosquitoes have been shown to act as vectors for other diseases in previous work.

"It's one of the most medically important species in Colorado and in the United States," said Rebekah Kading, assistant professor in CSU's Department of Microbiology, Immunology, and Pathology.

The researchers assessed the blood meals of mosquitoes at four sites - feedlots with and without livestock In Northern Colorado.

"Lab studies show these mosquitoes have very high transmission rates," said lead study author Daniel Hartman, a CSU doctoral student. "We've now found that this mosquito is in and near feedlots. It will bite a cow and, presumably, it would bite another cow. That's the complete transmission cycle for a virus. We also know that deer are highly susceptible to this virus, so we can look at the magnitude of transmissions."

The scientists want to know more about how the virus might spread. "With some of the mosquito species from our field study, we learned more about blood meals from deer and cattle," Kading said. "But there is little or no vector competence data available for them. Now, in the lab, we want to 'challenge' those mosquitoes, to see if they're capable of transmitting Rift Valley fever virus."

This virus can also spread from mosquito to offspring, and the researchers are investigating.

"The eggs get infected, so the female passes the virus on to offspring mosquitoes, which then continue to transmit the virus," explained study co-author Nicholas Bergren a postdoctoral fellow in the Kading lab.


Sources: AAAS/Eurekalert! via Colorado State University, Transboundary and Emerging Diseases

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAY 11, 2020
Cell & Molecular Biology
3D Cell Culture Model Suggests Herpes Can Cause Alzheimer's
MAY 11, 2020
3D Cell Culture Model Suggests Herpes Can Cause Alzheimer's
Alzheimer's is a common form of dementia that affects as many as 5.5 million Americans and the incidence is increasing a ...
MAY 23, 2020
Microbiology
The FDA Yanks Some COVID-19 Antibody Tests From the Market
MAY 23, 2020
The FDA Yanks Some COVID-19 Antibody Tests From the Market
The massive demand for diagnostic testing led the FDA to open a short window for many testing products to go to market w ...
MAY 25, 2020
Microbiology
The Symbiotic Bacteria That Stow Away in Ship-Destroying Clams
MAY 25, 2020
The Symbiotic Bacteria That Stow Away in Ship-Destroying Clams
Shipworms are known as the 'termites of the sea.' They are not actually worms; these infamous mollusks that have brought ...
JUN 14, 2020
Microbiology
Amping Up Immunity to Respiratory Viruses by Targeting Memory T Cells in the Lungs
JUN 14, 2020
Amping Up Immunity to Respiratory Viruses by Targeting Memory T Cells in the Lungs
It's easier than thought to activate immune cells that reside in the lungs and are involved in long-term immunity. Image ...
JUN 22, 2020
Microbiology
A Human Gut Microbe Can Help Maintain Healthy Cholesterol Levels
JUN 22, 2020
A Human Gut Microbe Can Help Maintain Healthy Cholesterol Levels
The world is full of microorganisms, and our bodies are one of the many places they have colonized. These gut microbes c ...
JUL 20, 2020
Microbiology
Evidence Continues to Support Universal Masking in the Fight Against COVID-19
JUL 20, 2020
Evidence Continues to Support Universal Masking in the Fight Against COVID-19
As the COVID-9 pandemic has spread around the world, scientists have tried to learn as much as they can about it, includ ...
Loading Comments...