SEP 23, 2019 1:54 PM PDT

Dengue Virus Changes According to the Temperature

WRITTEN BY: Carmen Leitch

Four related versions (or serotypes) of dengue virus are common in at least 100 countries, threaten around three billion people, and cause about 400 million infections every year, which may be mild or severe enough to cause deadly hemorrhagic fever and dengue shock syndrome.

Micrographs of DENV2 with different surface particles when incubated at different temperatures - the physiological temperatures of mosquitoes (29°C, left), human (37°C, middle) and humans with a high fever (40°C, right). / Credit: Xin-Ni Lim, Emerging Infectious Diseases Program

Reporting in PLOS Pathogens, researchers have now learned more about dengue virus serotype 2, DENV2, which is transmitted by mosquitoes and exists as a spherical particle that’s smooth at the mosquito body temperature (29 degrees Celsius) and becomes bumpy at human body temperature (37 degrees Celsius). Scientists want to know more about this change because it can help the virus evade detection by the human immune system.

"Together with Professor Pei-Yong Shi from UTMB, we found that in laboratory-developed DENV2 strains, mutations in the virus' E protein causes its transformation into bumpy particles. These structural changes can cause vaccines and therapeutics to be ineffective against the virus," explained the lead author of the study Xin-Ni Lim of Duke-NUS' Emerging Infectious Diseases (EID) Program.

In this work, the researchers also obtained samples of DENV2 from infected patients. They found that unlike the dengue viruses used in the laboratory, those from patients remained smooth at 37 degrees Celsius. At a fever temperature of 40 degrees, however, the bumpy surface emerged.

"Our study gives a new direction to vaccine development and treatment for dengue disease. For prevention of disease through vaccines that are administered to the patient before dengue infection, we should use those that are effective against the smooth surface virus. When it comes to patients displaying fever symptoms, treatment strategies effective against the bumpy surface particles should be implemented," noted the corresponding author of the report Dr. Sheemei Lok, a Professor at Duke-NUS' EID.

"This study is a first step towards gaining more insight into how DENV2 reacts and adapts to the host's immunological defenses. We were also able to use computational modeling approaches to predict why particles from different DENV2 strains are more or less adept at morphing from the smooth to bumpy structures. By better understanding the interactions between the virus and the host, we will be able to develop better therapies and vaccines to treat or prevent infections, and contribute to public health outcomes," added Dr. Peter Bond, Principal Investigator from A*STAR's BII.

This research indicates that DENV2 used in laboratory studies may be too dissimilar from the one found infecting people to be a good model. The scientists plan to investigate other serotypes of dengue virus to look for other changes.


Sources: AAAS/Eurekalert! via Duke-NUS Medical School, PLOS Pathogens

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
AUG 23, 2020
Microbiology
How Microbes Can Help Clean a Toxic River
AUG 23, 2020
How Microbes Can Help Clean a Toxic River
Some places in the United States have become dangerously polluted with hazardous waste. The EPA oversees a program that ...
AUG 31, 2020
Microbiology
Finding a Weakness in an Emerging Drug-Resistant Pathogen
AUG 31, 2020
Finding a Weakness in an Emerging Drug-Resistant Pathogen
Candida auris is a fungal pathogen that was initially reported in 2009. Its origins are unclear, but it has been found i ...
SEP 11, 2020
Microbiology
Bat Ticks Are Discovered in New Jersey
SEP 11, 2020
Bat Ticks Are Discovered in New Jersey
While only about 25 of 900 species of tick spread disease, ticks are responsible for an estimated 95 percent of vector-b ...
OCT 26, 2020
Immunology
Gearing up for Life: The First 7 Days of the Immune System
OCT 26, 2020
Gearing up for Life: The First 7 Days of the Immune System
The mother’s placenta serves as a shield for the developing fetus inside the womb, protecting it from the constant ...
NOV 12, 2020
Immunology
The Enzyme That Keeps Viruses In Stealth Mode
NOV 12, 2020
The Enzyme That Keeps Viruses In Stealth Mode
Some viral infections just don’t go away. The hepatitis C virus, for instance, can result in life-long chronic inf ...
NOV 23, 2020
Microbiology
Drug Resistance in Tuberculosis Involves a Unique Mechanism
NOV 23, 2020
Drug Resistance in Tuberculosis Involves a Unique Mechanism
The pathogenic bacterium that causes tuberculosis, Mycobacterium tuberculosis, does not multiply quickly, so researchers ...
Loading Comments...