Mosquitoes will take the spotlight, front line and center, this month.
On Wednesday, April 8, Regents Professor Michael Strand of the University of Georgia, Athens, and internationally recognized for his research on parasite-insect host interactions, will speak on "The Role of Microorganisms in Growth, Development and Reproduction of Mosquitoes” at the UC Davis Department of Entomology and Nematology seminar from 12:10 to 1 p.m. in 122 Briggs.
Next the Pacific Branch of the Entomologist Society of America (PBESA) will honor medical entomologist Thomas W. Scott, distinguished professor of entomology, UC Davis Department of Entomology and Nematology, at its 99th annual conference, April 12-15, in C'ouer d'Alene, Idaho. He will receive the coveted C. W. Woodworth Award for his outstanding work on dengue, a mosquito-transmitted disease.
And then on Friday, April 24, UC Davis will co-host the fourth annual Bay Area World Malaria Day Symposium, set from 8 a.m. to 4 p.m., Friday, April 24 on the Clark Kerr campus, UC Berkeley. UC Davis and Zagaya, a non-profit organization that envisions a malaria-free world, are partnering on the project.
Michael Strand Seminar April 8
Professor Strand's talk is much anticipated. "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 will be introduced by molecular biologist Shirley Luckhart, professor in the Department of Medical Microbiology and Immunology School of Medicine, and co-director of the UC Davis-based Center for Vector-borne Diseases (CVEC).
Talk will turn to dengue at the PBESA meeting in Co'eur d'Alene, Idaho. Professor Scott, who has researched mosquito-borne disease for 35 years and is retiring in June, is a global authority on the epidemiology of mosquito-borne disease, mosquito ecology, evolution of mosquito-virus interactions, and evaluation of novel products and strategies for mosquito control and disease prevention. Among the top vector biologists in the world, he is recognized as the leading expert in the ecology and epidemiology of dengue.
Scott is known for his holistic and comprehensive approach in finding solutions to protect the world's population from dengue, a disease that infects some 400 million per year. Some 4 billion people in 128 countries, more than half of the world's population, are at risk for dengue. Currently no vaccine or drug is effective against this life-threatening disease.
Scott's most significant research contributions concern the ecology and epidemiology of dengue:
- Blood feeding behavior, longevity, dispersal, and vector-virus interactions of the mosquito Aedes aegypti;
- Longitudinal cohort studies of spatial and temporal patterns in human dengue virus infection in Peru and Thailand; (dengue research in Peru, Thailand, Puerto Rico and Mexico for the past 25 years)
- Impact of human movement on mosquito contact rates and spatial dimensions of dengue virus transmission; and
- Mathematical and computer simulation modeling of mosquito population biology and mosquito-borne pathogen transmission.
Scott co-founded the Center for Vector-Borne Research (CVEC), comprised of researchers throughout the UC System. See more information on Scott.
Patrick Duffy, chief of the National Institutes of Health's Laboratory of Malaria Immunology and Vaccinology, will keynote the fourth annual Bay Area World Malaria Day Symposium, set Friday, April 24 on the Clark Kerr campus, UC Berkeley. The symposium, to take place from 8 a.m. to 4 p.m., will be co-hosted by UC Davis and Zagaya.
Duffy is an internationally recognized expert in human malaria pathogenesis, malaria in pregnancy, and malaria vaccine development. He has published more than 100 papers on malaria over his nearly 25-year career.
UC Davis co-host Shirley Luckhart, professor in the Department of Medical Microbiology and Immunology School of Medicine, and co-director of the Center for Vector-borne Diseases, will be one of the speakers.
Meanwhile, take a look at the spectacular mosquito images taken by entomologist/photographer Jena Johnson of Athens, GA (she is married to Michael Strand). This is the Aedes aegypti mosquito blood-feeding on her.
Quick! What do you think of when someone mentions "honey bees and mosquitoes" in the same sentence?
Honey bees are the pollinators, the beneficial insects. Infected mosquitoes transmit killer diseases such as malaria and dengue; they are our most dangerous insect enemies on the planet.
But, in a way, sometimes an apiculturist and a medical entomologist come together when they are honored for their decades of service to the University of California.
Take Extension apiculturist (emeritus) Eric Mussen, a bee guy, and medical entomologist William K. Reisen, a mosquito guy. Both retired last summer--Mussen after 38 years of service to UC, and Reisen, after 35 years of service. Between them, however, their length of service totals 82 years. That's because Reisen earlier served with the U.S. Air Force for three years and with the University of Maryland for six years.
Fittingly, both are receiving well-deserved honors for their accomplishments. Mussen's latest award was from the Almond Board of California for 38 years of meritorious service. Reisen's latest award is from the Mosquito Vector Control Association of California (MVCAC) for 35 years of meritorious service.
Reisen was nominated for the 2015 meritorious service award by the Contra Costa MVCAC District for "his special and significant contributions to the field of mosquito and vector control."
"Dr. Reisen's career spans over forty years during which he has published over 260 peer-reviewed publications and book chapters in the field of medical entomology," wrote nominator Craig Downs, general manager of the Contra Costa MVCAC District.
"Throughout his career, Bill has directed projects studying the vector competence of mosquitoes for newly introduced viruses, established new surveillance testing paradigms, and initiated complex interactive networks, sharing surveillance data with mosquito control agencies and public health officials to speed mosquito control response times and to minimize disease risk to humans. Several examples of his continual scientific contributions include: the effects of climate variation on arthropod-borne pathogen transmission, modeling efforts for predicting arbovirus risk, the application of insecticides for reducing the disease burden of West Nile virus in California, the use of liquid suspension array technologies for the identification of mosquito blood meals and his keen observation of the role of stagnant swimming pools as breeding sites for Culex spp. vectors in Sacramento County.”
Internationally known for his mosquito research and publications spanning more than four decades, Reisen is now professor emeritus, Department of Pathology, Microbiology and Immunology (PMI), School of Veterinary Medicine and serves as the editor of the Journal of Medical Entomology. He is a former director of the Center for Vectorborne Diseases (CVEC), comprised of researchers throughout the state and based on the UC Davis campus. Throughout his UC Davis career, Reisen has advised many graduate students affiliated with the UC Davis Department of Entomology and Nematology, PMI or CVEC. He is currently assisting four doctoral candidates and one master's degree candidate.
Reisen is one of only three UC recipients of this statewide award since 1981. William C. Reeves (1916-2004), UC Berkeley emeritus professor of epidemiology, received the award in 1981 and Bruce F. Eldridge, former director of the statewide UC Mosquito Research Program, based at UC Davis, and now professor emeritus of entomology, received the award in 1997.
Mussen's latest award is an engraved clock from the Almond Board of California. In presenting him with the coveted award, Robert "Bob" Curtis, associate director of Agricultural Affairs, Almond Board of California, told him: "Eric, we honor your service as a Cooperative Extension Apiculture Specialist. Your leadership has been invaluable to both the almond and beekeeping communities as the authoritative and trusted source for guidance on research, technical, and practical problem solving and issues facing both industries. Even now in your retirement you have been instrumental in the development of Honey Bee Best Management Practices for Almonds and extending this information to all pollination stakeholders."
For 38 years, Mussen served as a university liaison, Scientific Advisory Board member, reviewer of research proposals and a designated speaker for the Almond Board of California. As an emeritus, he continues some of that involvement. In addition to his many duties, for 38 years Mussen wrote and published the bimonthly newsletter, from the UC Apiaries, and Bee Briefs, providing beekeepers with practical information on all aspects of beekeeping. The UC Agriculture and Natural Resources (UC ANR) last year honored him with the Distinguished Service Award for Outstanding Extension.
Mussen, who joined the UC Davis department in 1976, became known throughout the state, nation and world as “the honey bee guru” and “the pulse of the bee industry" and as "the go-to person" when consumers, scientists, researchers, students, and the news media have questions about honey bees. (The new Extension apiculturist is Elina Niño from Pennsylvania State University. Check out her engaging and informative lab website.)
Mussen and Reisen may be far apart in their choice of insects to study, but they are close together in their commitment, dedication and passion that marked their phenomenal careers.
When he was doing research in Brazil in September, he draped a snake around his neck and posed for the camera.
His favorite research subjects, though, are mosquitoes.
- The yellow fever mosquito, Aedes aegypti, found throughout the tropics and subtropics and a newly invasive species in central California.
- The West Nile virus mosquito, Culex quinquefasciatus, found throughout much of the world.
- The malaria mosquito, Anopheles gambiae, which wreaks worldwide havoc.
Cornel's name appeared in the news this week when the UC Davis lab of Walter Leal announced that it had found the odorant receptor that repels DEET in the southern house mosquito, Culex quinquefasciatus mosquito. Cornel provided the mosquitoes that allowed the Leal lab to duplicate his colony. Proceedings of the National Academy of Sciences (PNAS) published the work Oct. 27.
Cornel's main research keys in on the population genetics and ecology of West Nile virus vectors in the United States and population genetics and ecology of major malaria vectors in Africa.
“Anton is a great asset to our program, a wonderful colleague, and a nice team player,” said Leal, a professor in the Department of Molecular and Cellular Biology. “We benefit greatly from his generosity by sharing not only mosquito colonies, but also his encyclopedic knowledge on mosquito biology and ecology. We shared co-authorship in a number of publications, and many more are coming.”
Cornel collaborates with Leal on oviposition attraction in Culex quinquefasciatus and “we are now endeavoring to come up with effective oviposition attractive chemical lures to use in virus surveillance and kill traps.”
“The invasion of Aedes aegypti into central California has been of great concern especially as current control methods do not appear to be working very well,” said Cornel, who works closely with state's mosquito abatement personnel. “We have found that the Aedes aegypti have insecticide resistance genes which likely explains why their ultra-low volume (ULV) and barrier spray applications have not worked as well as expected. Work will be ongoing next year when the Aedes aegypti become active again after a brief slow overwintering period from November to March.”
A native of South Africa, Cornel received his doctorate in entomology, focusing on mosquito systematics, in 1993 from the University of the Witwatersrand, Johannesburg. He completed a post-doctoral fellowship with the Entomology Branch of the Centers for Disease Control and Prevention (CDC), Atlanta, before joining UC Davis in 1997 as an assistant professor and researcher.
How did he get involved in mosquitoes? “My interest in mosquito research started in the mid-1980s when I agreed to conduct a masters study under the guidance of Dr. Peter Jupp at the National Institute of Virology who researched West Nile and Sindbis viruses transmitted by mosquitoes in South Africa,” Cornel recalled. “Thereafter I continued to work on mosquitoes as a scientist employed at the South African Institute for Medical Research before moving to the USA.”
“Who would have thought that that the expertise that I gained on West Nile virus as a master student in South Africa would be used many years later after West Nile virus invaded and spread throughout the USA?”
For more than two decades, Cornel has teamed with fellow medical entomologist and “blood brother” Professor Gregory Lanzaro of the UC Davis School of Veterinary Medicine to study malaria mosquitoes in the West African country of Mali. Their work is starting to show significant results.
“Because of our commitment to conduct long term longitudinal studies and not static investigations,” Cornel said, “we have now shown that considerable selective processes are taking place causing spatiotemporal dynamics of gene flow and fitness events in major malaria vectors M (now Anopheles coluzzii) and S (now Anopheles gambiae) and M/S hybrids in West Africa.”
“We are currently establishing further evidence of the important role of insecticide resistance traits in spatiotemporal dynamics of Anopheles coluzzii, Anopheles gambiae and the Bamako form.” Cornel noted that these results have “considerably important implications in future efficacies of insecticide treated bednets to control indoor biting malaria vectors in West Africa.”
Cornel also teams with Lanzaro and Professor Heather Ferguson of the University of Glasgow to examine the ecology and associated genetics of the major malaria vector Anopheles arabiensis in Tanzania. They began working on the project four years ago.
One of his newest projects is the study of population/genetics, insecticide resistance and cytogenetics in the major malaria vector in Brazil. Cornel and Lanzaro launched their study in September when they traveled to Brazil to begin targeting the culprit, Anopheles darlingi, a “widely distributed species that has adapted to survive in multiple ecological zones and we suspect that it may consist of multiple incipient or closely related species,” Cornel said.
“While in Brazil I collected larvae and dissected salivary glands from them to examine their polytene chromosome inversion structure and polymorphisms,” Cornel related. “Inversions are vitally important to consider in genetic analyses and it takes considerable patience to interpret the chromosomes.”
Cornel and Lanzaro collaborate with Professor Paulo Pimenta of the Laboratory of Medical Entomology, René Rachou Research Centre- FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil. The UC Davis medical entomologists hope to produce good preliminary data from their research trip to write grants and establish a long-term project in Brazil.
Cornel also studies avian malaria. That interest sparked four years ago when he began working in Cameroon with scientists from UCLA and San Francisco State University (SFSU), including SFSU's Ravinger Sehgal, who studies avian blood parasites. Cornel's graduate student Jenny Carlson, in her final year of her Ph.D studies at UC Davis, is investigating avian malaria in Fresno County.
The Cornel-Carlson research implicates that considerable fidelity exists between Culex mosquito species and species of plasmodium they transmit. “This is contrary to the currently held belief that all Culex mosquitoes are equally capable of transmitting avian malaria,” Cornel said. “In our investigations, we described a new species of avian malaria which is very common in songbirds in Fresno County (published in Parasitology Research).”
Cornel plans to continue working with Sehgal investigating the effects of deforestation on transmission of avian parasites in Cameroon. They recently submitted a National Science Foundation grant proposal. “A large swath of primary forest is slated to be deforested in Cameroon and replaced with Palm oil plantations and we will investigate the effects of this hopefully, as it happens.”
Also new on the horizon: Cornel will be starting a new mosquito-borne virus project in February. He received a Carnegie Foundation scholarly three-month fellowship to work in South Africa (February through to April). The primary objective of the project? To examine mosquito-borne viruses cycling in seven national parks in South Africa and two National Parks in Bostwana.
“It's extremely difficult to get permission to conduct field research in national parks in Southern Africa and this provides an unprecedented exciting opportunity for me to work with a friend, Professor Leo Braack from the University of Pretoria, in these parks. One has to be very careful working in some of these parks at night because of the wild predators, elephants, hippos and buffalo.”
Cornel is active in the 30- member Center for Vectorborne Diseases (CVEC), headquartered in the UC Davis School of Veterinary Medicine and considered the most comprehensive vectorborne disease program in California. Both interdisciplinary and global, CVEC encompasses biological, medical, veterinary and social sciences.
But then again medical entomologist Robert Washino isn't “most people.”
Washino, emeritus professor and former chair of the UC Davis Department of Entomology and former associate dean of the UC Davis College of Agricultural and Environmental Sciences, has just completed 38 years of service as a trustee of the Sacramento-Yolo Mosquito and Vector Control District (SYMVC) Governing Board.
And after 38 years, he's retiring from the board.
Washino has served longer than any other trustee in the history of the board. Indeed, that's almost four decades. The Davis City Council appointed him as the city's representative to the mosquito abatement board in 1973. It's a big district. The district covers 2000 square miles in Yolo and Sacramento counties.
The SYMVC board honored him at its Dec. 13th meeting, held in the district headquarters, Elk Grove, with a proclamation for his “exemplary public service and dedication to public health.” Next, the Davis City Council will present a proclamation at its meeting beginning at 6:30 p.m. Tuesday, Dec. 20 in the Community Chambers, 23 Russell Blvd.
Washino, now 79, served as president of the board five times during his tenure.
The SYMVC laboratory/library is named in his honor. Washino gifted his entire collection of mosquito-related books and journals, photographs and slides to the district for research and teaching purposes.
Internationally known for his expertise on mosquitoes, “Dr. Washino brought a perspective to the board that is difficult to replace,” SYMVC Manager David Brown said. “He is known worldwide for his work on mosquitoes and public health and bringing that knowledge to the district has provided a level of service that is hard to match. Without his guidance and tutelage, I am sure our program would not be as effective as it is today.”
One of the highlights of his career occurred in 2005 when he received the international Harry Hoogstraal Medal for Outstanding Achievement in Medical Entomology for his work on the ecology of mosquitoes and mosquito control agents.
He also has a mosquito named for him: Aedes washinoi.
"It's a tiny one," he says.
So, Bob Washino, mosquito man extraordinaire, is stepping down. We're not sure, though, that he can ever totally step down.
He has too much public service in his heart.
An article in the July 21st edition of Nature asked that very question.
Author Janet Fang, an intern in Nature's Washington, D.C., office, wrote that "Malaria infects some 247 million people worldwide each year, and kills nearly one million. Mosquitoes cause a huge further medical and financial burden by spreading yellow fever, dengue fever, Japanese encephaltis, Rift Valley fever, Chikungunya virus and West Nile virus."
So, how about a world without mosquitoes? "Would anyone or anything miss them?" she asked.
Fang went on to ask scientists that very question. But the fact is, they're here and they're not going anywhere--except over here to bite us.
Meanwhile, over in the UC Davis Department of Entomology, two graduate students just received William Hazelton Memorial Fellowship Awards to further their mosquito research.
Tara Thiemann (top photo), a doctoral candidate studying with major professor William Reisen, received $2100 for her statewide research on bloodfeeding patterns of Culex mosquitoes. She studies both urban and rural populations of mosquitoes and their host meals.
Jenny Carlson (bottom photo), an incoming doctoral student who will be studying with major professor Anthony 'Anton' Cornel, received $2000 for her research on avian malaria parasites.Thiemann's project involves analyzing the blood meals of Culex mosquitoes to identify specific host species--research important toward understanding both the maintenance and epidemic transmission of the West Nile virus.
Carlson’s research will take her to West Africa where she will collect mosquito vector and avian blood samples to study the mechanisms of malaria parasite transmission. She hypothesizes that the diversity of mosquito and avian parasites will be lower in deforested areas than forested areas.
The award memorializes William “Bill” Hazeltine (1926-1994), who managed the Lake County Mosquito Abatement District from 1961-64 and the Butte County Mosquito Abatement District from 1966-1992. He was an ardent supporter of the judicious use of public health pesticides to protect public health. He continued work on related projects until his death in 1994.
Hazeltine studied entomology in the UC Berkeley graduate program from 1950-53, and received his doctorate in entomology from Purdue University in 1962.
UC Davis medical entomologist Bruce Eldridge eulogized Hazeltine at the 2005 American Mosquito Control Association conference. His talk, "William Emery Hazelton II--Rebel With a Cause," was later published in the Journal of the American Mosquito Control Association. (See PDF)
It's good to know that Hazeltine's cause lives on through his family's generosity.