- Author: Kathy Keatley Garvey
The lecture, to take place at 10:45 a.m. in the Alpha Gamma Rho (AGR) Hall, is sponsored by the College of Agricultural and Environmental Sciences and the Storer Life Sciences Endowment of UC Davis.
At Penn State, Thomas serves as the Huck Scholar in Ecological Entomology and directs the Ecology Institute, in addition to his duties as a professor of entomology in the Department of Entomology and Centre for Infectious Disease Dynamics.
He will be introduced by Professor Shirley Luckhart of the UC Davis Department of Medical Microbiology and Immunology, coordinator of the event.
Thomas researches many aspects of the ecology and evolution of insect pests and diseases in his drive to understand the consequences of global change and to improve the effectiveness and sustainability of pest and disease management. His work involves predicting and understanding the impact of invasive species, and researching biodiversity and ecosystem health, plus many aspects of biological control.
Last December Thomas and his research team at Penn State, in collaboration with partners in Europe and Africa, received a five-year, $10.2 million grant from the Bill and Melinda Gates Foundation to investigate a new method for preventing the transmission of malaria.
“The method involves limiting mosquito access to houses by blocking openings and installing ‘eave tubes' that contain a unique type of insecticide-laced mosquito netting developed by Dutch partner In2Care that kills the insects as they attempt to enter,” according to a Penn State news release.
Thomas was quoted as saying: “Nearly half of the world's population is at risk of contracting malaria, and according to the most recent World Health Organization report, an estimated 438,000 people died from the disease in 2015. The use of insecticides to control mosquitoes has saved millions of lives, but this tactic is increasingly challenged because mosquitoes quickly evolve resistance to the very limited number of insecticides currently used in public health. The eave tube approach presents a novel strategy to help combat this challenge by simultaneously making houses more mosquito proof and providing a novel way of delivering insecticides, which creates opportunities for using a wider range of insecticidal products."
"The small amount of insecticide used in the tubes means that it is cheap to treat an entire house," said Thomas. "Furthermore, retreatment is easy, as it requires simple replacement of small pieces of netting within the tubes."
Internationally recognized, Thomas is a recipient of the Commonwealth Scientific and Industrial Research Organization (CSIRO) Medal for Research Achievement, is a fellow of the American Association for the Advancement of Science, and an honorary professor at the University of Witwsatersand, South Africa. He also received Penn State's Alex and Jessie Black Award for Research Excellence.
- Author: Kathy Keatley Garvey
The book, published by Oxford University Press, will be available for purchase that night or attendees may bring their own copy for signing.
The event is co-sponsored by Jay Rosenheim, professor of entomology, UC Davis Department of Entomology and Nematology, and by the department. Epstein is a longtime research associate and friend of Rosenheim's.
Epstein is a senior insect biosystematist for the order Lepitopdera (butterflies, moths) with the Plant Pest Diagnostics Branch, California Department of Food and Agriculture. He is a research associate for the National Museum of Natural History (NMNH), Smithsonian Institution.
Harrison G. Dyar Jr. (1866-1929) was a Smithsonian entomologist of the early 20th century. He was a taxonomist who published extensively on moths and butterflies (Lepidoptera), mosquitoes (Diptera: Culicidae), and sawflies (Hymenoptera: Symphyta). As a teenager, he studied insects, particularly moths. He received his bachelor's degree in chemistry in 1889 from the Massachusetts Institute of Technology, and his master's degree in biology from Columbia University in 1894. His doctoral dissertation (1895) dealt with airborne bacteria in New York City.
"On September 26, 1924, the ground collapsed beneath a truck in a back alley in Washington, D.C., revealing a mysterious underground labyrinth. In spite of wild speculations, the tunnel was not the work of German spies, but rather an aging, eccentric Smithsonian scientist named Harrison Gray Dyar, Jr. While Dyar's covert tunneling habits may seem far-fetched, they were merely one of many oddities in Dyar's unbelievable life.
"For the first time, insect biosystematist Marc E. Epstein presents a complete account of Dyar's life story. Dyar, one of the most influential biologists of the twentieth century, focused his entomological career on building natural classifications of various groups of insects. His revolutionary approach to taxonomy, which examined both larval and adult stages of insects, brought about major changes in the scientific community's understanding of natural relationships and insect systematics. He was also the father of what came to be known as Dyar's Law, a pragmatic method to standardize information on insect larval stages as they grow. Over the course of his illustrious career at the U.S. National Museum, Smithsonian Institution from 1897-1929, Dyar named over 3,000 species, established the List of North American Lepidoptera, an unrivaled catalog of moths and butterflies, and built one of the nation's premier lepidoptera and mosquito collections.
"However, Dyar's scientific accomplishments are a mere component of this remarkable biography. Epstein offers an account of Dyar's complicated personal life, from his feuds with fellow entomologists to the scandalous revelation that he was married to two wives at the same time. Epstein also chronicles Dyar's exploration of the Baha'i faith, his extensive travels, his innumerable works of unpublished fiction, and the loss of his wealth from bad investments. Comprehensive and engaging, Moths, Myths, and Mosquitoes will delight entomologists and historians alike, as well as anyone interested in exploring the zany life of one of America's virtually unknown scientific geniuses."
Epstein researches and writes on evolution and classification of moths and their biodiversity, and develops identification tools for moths that threaten agriculture. He served with NMNH's Department of Entomology (1988-2003), co-founding the department's Archives and Illustration Archives.
Epstein's research on caterpillars, including images and videos, is featured in the NMNH exhibit "More than Meets the Eye." He was a guest on NPR's "Fresh Air" about his work on the book "Night Visions: the Secret Design of Moths." Epstein's published work includes a Smithsonian monograph on limacodid moths and the article "Digging for Dyar: the Man Behind the Myth" with Pamela M. Henson.
Epstein received his master's degree (1982) and doctorate (1988) from the University of Minnesota.
For more information on the April 28th event, contact Jay Rosenheim at jarosenheim@ucdavis.edu.
- Author: Kathy Keatley Garvey
“It's an issue of great concern, especially as current control methods do not appear to be working well,” said Cornel, who does research on the mosquito in Clovis, Fresno County, where it was discovered in June 2013. Simultaneously, the insect was found in the cities of Madera and San Mateo.
“This ongoing widespread invasion and establishment proves that this is no longer a regional issue and has affected many cities and towns in California,” he wrote Feb. 8 in F1000 Research, http://f1000research.com/slides/5-149.
But Cornel is optimistic that the pest management intervention strategies and surveillance and control tactics now underway will help control its spread. Infected Aedes aegypti can transmit dengue, yellow fever, Zika and chikungunya viruses.
The Zika virus, now spreading throughout the Western hemisphere, is an emerging mosquito-borne virus that was first identified in Uganda in 1947 in rhesus monkeys, according to the World Health Organization. It was subsequently identified in humans in 1952 in Uganda and the United Republic of Tanzania. Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Asia and the Pacific.
Despite the mosquito's invasion in parts of the United States, there are no reported cases of locally transmitted Zika virus in California or in the contiguous United States, according to the Centers for Disease Control and Prevention. The cases have all involved travelers returning home from countries plagued with disease outbreaks.
Cornel works with the Consolidated Mosquito Abatement District, based in Fresno County, to tackle the spread of the mosquito there. The district covers 1,058 square miles, including part of Kings County.
How far north in California will the mosquito, commonly known as yellow fever mosquito, spread?
“I don't want to exclude the possibility that it may spread as far north as Sacramento,” said Cornel, who collects, rears and researches mosquitoes from all over the world, including the United States, Mali, Cameroon, Comoros, Tanzania, South Africa and Brazil. “We need to see if it overwinters as eggs or adults or both.”
It's troubling that the mosquito is becoming more and more resistant to pesticides, Cornel said. “We have found that the Aedes aegypti have insecticide resistance genes which likely explains why their ultra-low volume and barrier spray applications have not worked as well as expected.”
At Clovis, Cornel and his colleagues trap mosquitoes in gravid or ovitraps; study overwintering and flight dispersal; and employ mark-release-capture trials to estimate dispersal and population size, needed to plan biological (Wolbachia) and chemical auto-dissemination control strategies. They also engage in “recruiting” mosquitoes to kill other mosquitoes. “We have mosquitoes spread insecticides for us, that is, we turn them into mosquito-control workers through the use of insect growth regulators and biopesticides.”
Their 27-slide document, “Surveillance and Control of Aedes aegypti Mosquito in Clovis, Calif.,” published in F1000 Research details their research with text and maps. It is work of Cornel and Yoosook Lee of UC Davis; Stephen Dobson of the University of Kentucky; Corey Bansfield of MosqMate Inc. and Jodi Holeman, Mark Amireno, Charles Smith and Stephen Mulligan III of the Consolidated Mosquito Control District. In the document, Mulligan, director of the Consolidated Mosquito Control District, describes Aedes aegypti as “the rat of the mosquitoes.”
The California team works with University of Kentucky scientists to develop novel control strategies. One trial involves coating male mosquitoes with insect growth regulators, which are passed on to the females. Males are also infested with a biopesticide or “a good bacteria-like organism,” Wolbachia. “The male transfers it to the female, which affects the ovaries and negatively affects immature development,” Cornel explained. “It's not new, but it's not been employed in large trials.”
Regarding flight dispersal, Cornel has found that “males can fly well over 200 meters in one night from their breeding site. We previously thought it was no more than 60 to 100 meters.”
“The Aedes aegypti fly predominantly during cooler periods of the day,” the medical entomologist said. “When it's too hot, they hang around the shade.” When residents walk at dusk, both male and female mosquitoes can follow them. “Only the females bite but the males will hang around your ankle waiting for the females to arrive.”
The researchers target mosquito breeding sites, primarily yard drains. “Despite the drought and the elimination of visible bodies of water, such as bird baths, pet bowls and flower pots, there's a major issue: yard drains,” Cornel said. “Yard drains installed in new home developments empty into the gutter or street and are cryptic breeding sites for mosquitoes.” He speculates that these mosquitoes are breeding underground.
“These drains are not easily accessible and we can't see the mosquitoes,” Cornel pointed out. “We need to blow out the water and plug these yard drains to eliminate these breeding sites.” He suggests that cities everywhere address this public safety issue and “redesign the yard drains.”
Cornel works with the Consolidated Mosquito Abatement District in setting gravid or “killing traps” in the front yards of homes in Clovis. The traps, which look like five-gallon buckets, contain orchard grass and water. “When the orchard grass decomposes, it releases a plume of chemicals that attracts female Aedes aegypti to lay their eggs in,” Cornel said. A screen prevents them from reaching the water to lay their eggs. The insects adhere to black sticky paper.
It's crucial for the public to become involved, Cornel said. “We have to focus on public education. We have to get the message across to eliminate mosquito breeding sites. We can't go to every house. We must rely on the public to eliminate the breeding sites.”
It's possible—but he hopes not—that what is now a “mosquito nuisance” will result in a disease outbreak.
Related Links:
- Anthony Cornel: Mosquito Man UC Davis Department of Entomology and Nematology
- Anthony Cornel, Kearney Agricultural Research and Extension Center
- Yoosook Lee, UC Davis Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine
- F1000 Research
- Traps Tested in Clovis (UC ANR)
- Aedes aegypti, California Department of Public Health, Aedes aegypti
- Consolidated Mosquito Control District, based in Fresno County
- Author: Kathy Keatley Garvey
The seminar is from 12:10 to 1 p.m.
"Mosquitoes are well recognized as the most important arthropod vectors of disease-causing pathogens," Strand says in his abstract. "Interest in the gut microbiota of mosquitoes has risen recently as a potential tool for manipulating vector competency. In contrast, much less is known about the role of this community in mosquito growth, development and reproduction. In this talk I will discuss recent results from our lab group regarding the composition of the gut microbiome in different mosquito species and insights we have gained about the function of this community in mosquito biology and evolution."
Strand focuses his research in the areas of parasite-host interactions, virology, immunity and development. Current projects center on virus-host interactions, function of the insect immune system, and regulation of reproduction in mosquitoes and other insects.
Strand was nominated as a seminar speaker by Professor Shirley Luckhart, Department of Medical Microbiology and Immunology, UC Davis School of Medicine and a graduate student advisor, UC Davis Department of Entomology and Nematology; Associate Dean Ed Lewis of the College of Agricultural and Environmental Sciences and professor and vice chair of the UC Davis Department of Entomology and Nematology; and Distinguished Professor James R. Carey, UC Davis Department of Entomology and Nematology.
A native of Norfolk, Va., Strand grew up in Texas. He received both his bachelor's degree in entomology (1980) and his doctorate in entomology (1985) from Texas A&M University, College Station. He accepted a fellowship from the National Science Foundation-North Atlantic Treaty Organization (NATO) as a postdoctoral scholar at the Imperial College, University of London in 1986. He then accepted a position as an assistant professor at Clemson University. In 1987, joined the faculty of the University of Wisconsin-Madison where he advanced to the position of professor. In 2002, Strand moved to the University of Georgia where he holds appointments in the Department of Entomology, the Center for Tropical and Emerging Global Diseases, Faculty of Infectious Diseases, and Department of Genetics.
Strand is a fellow of the Entomological Society of America (selected in 2012) and the American Association for the Advancement of Science (2008). ESA presented him with the national recognition award in the Physiology, Biochemistry and Toxicology Section in 2009. He served as president of the section in 2013.
Plans call for his seminar to be video-recorded and then posted at a later date on UCTV. The departmental seminars are coordinated by Professor Steve Nadler.
Links:
Upcoming seminars
Seminars Posted on UCTV
Bay Area World Malaria Day Symposium on April 24: Register now!
- Author: Kathy Keatley Garvey
The seminar will take place from 12:10 to 1 p.m. in 122 Briggs. Host is Jiawen Xu, a graduate student in the Bruce Hammock lab.
"Transmission of human disease-causing agents by mosquitoes depends on the successful completion of the pathogen's infection-cycle in the insect vector," Dimopoulous said. "The mosquito's innate immune system and microbiota represent important bottlenecks for pathogen transmission, and can thus be exploited for the development of novel disease control strategies." He will discuss "advances in our understanding of how the mosquito immune system and natural microbiota can influence Plasmodium and dengue virus infection in their respective vectors."
Dimopoulous has more than 20 years experience with molecular entomology of the vectors Anopheles. gambiae and Ae. aegypti. His research has mainly focused on the mosquito's innate immune system and the mosquito midgut microbiota, and how they interact with various the human pathogens Plasmodium falciparum and the dengue virus, using genomics, functional genomics and molecular biology techniques and approaches. His group's research over the past 8 years has contributed significantly toward the understanding of how the mosquito innate immune system and microbiota influences the mosquito and its permissiveness to human pathogen infection.
Dimopoulous received his bachelor's degree in microbiology from Stockholm University, Sweden, and his doctorate in biology from the University of Crete, Greece. He did postdoctoral work in molecular entomology at the European Molecular Biology Laboratory, Heidelberg, Germany from 1996 to 2001. In 2007 he obtained his master's of business administration from Carey Business School, Johns Hopkins University, studying management and leadership.
Since 2013, Dimopoulous has served as an adjunct professor in the Department of Microbiology and Medical Zoology, School of Medicine, University of Puerto Rico, San Juan.
Professor Steve Nadler chairs the UC Davis Department of Entomology and Nematology seminars. Most are recorded for later posting on UCTV.
See schedule for remaining seminars of the quarter.