February 18, 2019
Profile of 2018 MCE-VBD Research Fellow Sulagna Chakraborty
I am an MCE-VBD 2018 Research Fellow from the University of Illinois, and I had the opportunity to be involved in several projects under the mentorship of Dr. Marilyn O’Hara Ruiz and Dr. Rebecca Smith.
I was part of the summer field surveillance team in Illinois that collected the ticks of interest namely Ixodes scapularis, Amblyomma americanum and Dermacenter variabilis. I worked on a project to determine the optimum number of mosquito traps necessary to determine accurate MIR for Illinois using the value of information concept. Additionally, I worked on a literature review of the role of cattle and livestock in vector borne diseases. The combination of these projects provided perspective on the current state of VBD research done at the public health departments and University level. I also realized the different responsibilities and processes that are part of VBD-related work.
Sulagna assisting with tick dragging in Effingham County, during the Southern Illinois Tick Blitz in June 2018
This fellowship helped me gain a lot of experience in field surveillance and the different methods of tick collection such as timed dragging versus dual crossed profile transect dragging in addition to the importance of site selection. I also learned about field data collection and recording processes and quick identification of the collected ticks. I believe if I have to collect my own tick data this experience will be very useful. The literature summary also helped me understand the myriad ways in which cattle are involved in different VBDs that impact both animals and humans. Although, the exact mechanism by which cattle may help in the amplification of pathogen/s or the maintenance of vector/s in the environment is unknown, this review exposed me to this area of research.
Preparing I-TICK Surveillance Kits
I was present on the statewide All Hands meetings, as I learned about surveillance, case follow up and the preventative steps that were taken by the different states’ public health departments. I subscribe to Pro-MED alerts and keep reading reports of different outbreaks in every corner of the world, but this time I was aware of cases that occurred and was privy to the steps that were taken, even before Pro-MED reported the news. This was definitely one of the highlights of my fellowship and helped me gain more understanding of the procedures in surveillance and monitoring of diseases.
I believe through this fellowship I developed critical skills and also insights into the kinds of work done in VBD research which will shape my career trajectory in graduate school and in the future.
January 22, 2019
Media Reports on UW-Madison Researchers Using Bacteria in Worms as Mosquito Repellent
Bacteria In Worms Make A Mosquito Repellent That Might Beat DEET
January 16, 2019
Jonathan Lambert, NPR
The next great insect repellent might come from a strain of bacteria that lives inside a common parasitic worm.
A study published Wednesday in Science Advances has found that a compound derived from these bacteria is three times more potent than DEET in repelling mosquitoes. More research must be done to demonstrate its safety, but this bacterial chemical could play an important role in the fight against mosquito-borne illness.
Susan Paskewitz, a professor of entomology at the University of Wisconsin-Madison who oversaw the study, explains that the project started in the lab of her late colleague, Que Lan. She and her student Il-Hwan Kim were studying bacteria called Xenorhabdus budapestensis, which lives inside the tiny roundworms called nematodes. These nematodes parasitize insects in the soil, sneaking into their bodies and releasing hordes of Xenorhabdus, which soon kill the insect. Then, without the insect's immune system to contend with, the nematodes devour the carcass and multiply.
According to Paskewitz, Lan wanted to crack Xenorhabdus' insecticidal code in hopes that it might lead to a novel mosquito killer. She put the bacteria into the artificial blood supply she feeds to her mosquito colonies, hoping they would ingest the bacteria and she could track whether the mosquitoes were harmed. But her mosquitoes wouldn't go anywhere near the treated blood, much less ingest it. "The mosquitoes would die from drying out rather than touch the thing," says Paskewitz. That observation stuck in Paskewitz's mind, suggesting that something produced by these bacteria make might be useful as an insect repellent.
Read more here.
A new kind of mosquito repellent that comes from bacteria
January 17, 2019
Kelly April Tyrrell, UW-Madison
People may soon have a new weapon in the battle against mosquitoes, and it comes from an unusual source: bacteria.
Published Jan. 16 in the journal Science Advances, University of Wisconsin–Madison researchers describe the first mosquito-repelling compounds to be derived from the microbes.
These compounds, purified from extracts from the bacterium Xenorhabdus budapestensis, appear to work at lower doses than repellents currently on the market, including DEET and picaridin. The study showed them to be effective against Aedes aegypti, Anopheles gambiae and Culex pipiens, mosquito species known to transmit diseases such as Zika, West Nile, malaria and chikungunya, diseases that afflict millions of people worldwide,.
Whether these natural chemical compounds, called fabclavines, are suitable for human use remains to be determined, but the study, says UW–Madison Professor of Entomology Susan Paskewitz, opens up a new area of exploration in the search for insect-repelling and insect-killing compounds.
“We didn’t come at it thinking we would find a repellent,” she says. “It was a bit of serendipity.”
In fact, the project did not begin with Paskewitz at all. It started with her colleague, Que Lan, who tragically passed away in 2014 from complications of cancer. At the time, Lan was looking for bacterial compounds that would kill mosquitoes. Paskewitz helped secure additional funding to keep the study going and found a scientist, lead study author Mayur Kajla, interested in carrying the work forward.
When Kajla joined the project, the research team already knew that extracts from the bacteria did not kill mosquitoes but when it was added to their food, the mosquitoes refused to eat. He designed a set of experiments to test the repellent potential of the bacterial extract and identify the compounds responsible.
Using a commercial mosquito feeding system, Kajla made modifications to more closely mimic a mosquito feeding on a human being. For instance, he selected a skin-like membrane to contain a special, red-dyed mosquito diet that simulates human or animal blood. He also tested a variety of cloth coverings to sit atop the membrane, which would be coated with the repellents being screened.
Kajla coated the cloth with water, DEET or picaridin and allowed mosquitoes to feed for 30 minutes before freezing them and counting the number that were engorged with red liquid (fed) or unfed. The mosquitoes did not feed when the cloth was coated in repellent.
Read more here.
January 17, 2019
Profile of 2018 MCE-VBD Research Fellow Karina Burmeister
My summer as a Research Fellow at the Midwest Center of Excellence for Vector-Borne Disease was challenging, educational, and enjoyable. The work I performed consisted of tick-dragging, tick identification, and small mammal trapping.
We dragged for ticks at the UW Arboretum and in the Chequamegon-Nicolet National Forest. We collected all three life stages of tick: larvae, nymph and adult. In the lab, we would identify them, typically seeing Ixodes scapularis (deer tick) or Dermacentor reticulatus (wood tick). We did this to determine tick density throughout Wisconsin and to test to see the bacteria’s the ticks were carrying.
I was also involved in small mammal trapping, which involved setting Shermann live traps overnight to trap mice and other small mammals. We would then take blood samples, ear punches (a small piece of skin from the ear), pull ticks off of them, and ear tag them. The goal of the PhD project was to study two lyme disease reservoirs, Peromyscus maniculatus (deer mouse) and Peromyscus leucopus (white-footed mouse). We were comparing disease prevalence, tick burdens, nest site preferences, distance traveled, and temporal activity. We also put radio collars on a representative population of both species to track their distances traveled.
One moment from the fellowship that sticks out to me was on a recent fellow conference call when were able to speak with P.J. Liesch from the Insect Diagnostic Lab at UW. P.J. shared that he did not go into his career interested in public speaking and outreach. He encouraged the fellows to take any opportunity given and that we never know where it may lead. It was inspiring to hear from an expert in the field and about the steps he took to get to his current career.
The bigger picture reinforced from this experience is that ecology, wildlife, and human health are very interconnected. The more we know about carriers of disease such as the white-footed mouse and the deer mouse, the more we can learn about human health and further take preventative measures against disease. Working for the Center has allowed me to see how vector-borne disease is being addressed first hand. MCE-VBD and my fellowship work looks at the bigger picture. Not only are we studying tick densities, but small mammals that carry ticks, the bacteria’s that the mammals have, and the bacteria’s that the ticks are carrying. I believe that coming at vector-borne disease from such a wide angle will truly improve public awareness and health.
This fellowship was impactful in aiding me in career studies. This was my favorite experience so far in my career field. It has taught me how passionate I am about being in the field, but also how valuable and necessary lab work and data analysis are. My plan is to apply to a graduate program to further study wildlife and vector-borne disease, to become a professor.
November 29, 2018
CDC releases papers highlighting tick borne disease and the recently emerged tick species Haemaphysalis longicornis
OA Combatting the Increasing Threat of Vector-Borne Disease in the United States with a National Vector-Borne Disease Prevention and Control System
The American Journal of Tropical Medicine and Hygiene
Reported cases of vector-borne diseases in the United States have more than tripled since 2004, characterized by steadily increasing incidence of tick-borne diseases and sporadic outbreaks of domestic and invasive mosquito-borne diseases. An effective public health response to these trends relies on public health surveillance and laboratory systems, proven prevention and mitigation measures, scalable capacity to implement these measures, sensitive and specific diagnostics, and effective therapeutics. However, significant obstacles hinder successful implementation of these public health strategies. The recent emergence of Haemaphysalis longicornis, the first invasive tick to emerge in the United States in approximately 80 years, serves as the most recent example of the need for a coordinated public health response. Addressing the dual needs for innovation and discovery and for building state and local capacities may overcome current challenges in vector-borne disease prevention and control, but will require coordination across a national network of collaborators operating under a national strategy. Such an effort should reduce the impact of emerging vectors and could reverse the increasing trend of vector-borne disease incidence and associated morbidity and mortality.
Full paper available here
Multistate Infestation with the Exotic Disease–Vector Tick Haemaphysalis longicornis — United States, August 2017–September 2018
Morbidity and Mortality Weekly Report (MMWR)
C. Ben Beard, PhD1; James Occi, MA, MS2; Denise L. Bonilla, MS3; Andrea M. Egizi, PhD4; Dina M. Fonseca, PhD2; James W. Mertins, PhD3; Bryon P. Backenson, MS5; Waheed I. Bajwa, PhD6; Alexis M. Barbarin, PhD7; Matthew A. Bertone, PhD8; Justin Brown, DVM, PhD9; Neeta P. Connally, PhD10; Nancy D. Connell, PhD11; Rebecca J. Eisen, PhD1; Richard C. Falco, PhD5; Angela M. James, PhD3; Rayda K. Krell, PhD10; Kevin Lahmers, DVM, PhD12; Nicole Lewis, DVM13; Susan E. Little, DVM, PhD14; Michael Neault, DVM15; Adalberto A. Pérez de León, DVM, PhD16; Adam R. Randall, PhD17; Mark G. Ruder, DVM, PhD18; Meriam N. Saleh, PhD14; Brittany L. Schappach10; Betsy A. Schroeder, DVM19; Leslie L. Seraphin, DVM3; Morgan Wehtje, PhD3; Gary P. Wormser, MD20; Michael J. Yabsley, PhD21; William Halperin, MD, DrPH22
Full report available here
November 16, 2018
Check this out- Tick Check 1-2 (Lyme Disease Prevention Rap) Video
The Division of Environmental Health in Fairfax County, Virginia released a rap video earlier this year to help promote the importance of tick bite prevention and treatment in a fun and lighthearted way. The video features rapper and tick biologist Andy Lima, as MC Bugg-Z.
See the video and the entire Fairfax County tick prevention webpage here.
November 15, 2018
Tickborne Disease Working Group Releases 2018 Report to Congress
The U.S. Department of Health and Human Services' Tick-Borne Disease Working Group released its 2018 Report to Congress this week. The report highlights the growing public health threat of tick-borne disease nationally and recommends a multi-pronged response to the problem that includes surveillance, biological and clinical research, education, and health provider outreach.
A copy of the report's Executive Summary is provided here. The full report can be found here.
TICK-BORNE DISEASES have rapidly become a serious and growing threat to public health in the United States. Despite many scientific unknowns, experts agree that the incidence and distribution of tick-borne diseases are increasing. Over the past 25 years, reports of Lyme disease have increased steadily with estimated annual cases approximating 300,000 (Hinckley et al., 2014; Nelson et al., 2015). The number of U.S. counties now considered to be of high incidence for Lyme disease has increased by more than 300% in the Northeastern states and by approximately 250% in the North-Central states. The Centers for Disease Control and Prevention (CDC) currently recognizes 18 tick-borne pathogens in the United States. However, researchers and health care practitioners continue to discover emerging disease agents and new medical conditions associated with tick bites.
While most Lyme disease patients who are diagnosed and treated early can fully recover, 10 to 20% of patients suffer from persistent symptoms, which for some are chronic and disabling. Studies indicate that Lyme disease costs approximately $1.3 billion each year in direct medical costs alone in the United States. A comprehensive understanding of the full economic and societal cost remains unknown. It is likely orders of magnitude higher and potentially a $50- to $100-billion-dollar problem for the United States, although more research is needed (Vanderhoof & Vanderhoof-Forschner, 1993; Zhang et al., 2006). Prompt diagnosis and treatment of tick-borne diseases are crucial to prevent long-term complications. Today, available diagnostic tests can be inaccurate and complex to interpret, especially during the earliest stage of infection when treatment is most effective. Unlike in other infectious disease settings, tests to directly measure the presence of the infecting organism, such as cultures or tissue biopsies, are not available for some tick-borne diseases such as Lyme disease. This leaves physicians without the tools needed to diagnose; and without an accurate diagnosis, it is challenging for physicians to provide early treatment.
Persistent symptoms after treatment of Lyme disease can be severe, yet their cause(s) remains unknown and debated. There are currently no uniformly accepted or validated treatment options for patients with these chronic symptoms. As a result, uncertainty surrounding appropriate clinical care has led to polarization within the medical community, and patients are often left suffering in limbo without a clear path to illness resolution or even symptom management (Rebman et al., 2017). The lack of a clear path for treatment of persistent symptoms in some patients with Lyme disease and other tick-borne diseases not only amplifies patient suffering but also significantly increases health care costs.
This report outlines an integrated, multipronged approach to the growing public health challenges posed by tick-borne diseases in the United States. It contains nine main chapters, including Background; Methods; Epidemiology and Ecology; Prevention; Diagnosis; Treatment; Access to Care, Patient Outcomes; Looking Forward; and Conclusion. The Background and Methods chapters explain how the report was developed. The other chapters present the main challenges, key issues, and recommendations specific to the broader topics.
To understand tick-borne diseases, we need to first understand tick ecology and how ticks transmit diseases. Due to the lack of a coordinated national surveillance program, currently there are significant gaps in information on local distribution of infection-causing ticks, especially in regions beyond the Northeast and Upper Midwest. Nationwide, standardized approaches for tick, animal, and human
surveillance are needed to understand the geographic distribution of infectious ticks in order to understand the spread of disease and predict where people are at risk. Advanced technologies and systematic studies are also needed to rapidly identify new disease agents that pose emergent risks to public health, including to the blood supply. Given that seven new tick-borne pathogens have been shown to infect people in the United States since 2004, this is a priority.
Effective prevention relies on multipronged strategies. To reduce exposure to ticks, we need a comprehensive understanding of the biological drivers behind the continued spread of tick-borne diseases, so that effective tick- and infection control methods can be identified and validated. Need also exists for the transparent development of a safe, effective human vaccine to prevent Lyme
disease, the most common of these illnesses. In the absence of effective strategies for controlling ticks and blocking the transmission of tick-borne pathogens, it is crucial to educate health care professionals and the public about tick-borne disease prevention, especially best practices for protection from tick bites. Outreach efforts to promote prevention and raise awareness among physicians and the public must be expanded at both the Federal and state level to ensure accurate, effective, and consistent messaging.
Clinical research priorities must include the development of new technologies and approaches to improve diagnosis of tick-borne diseases and monitor response to treatment. There is a critical need for sensitive and specific direct-pathogen detection strategies that are broad enough to cover multiple potential tickborne pathogens. Understanding the etiology and pathogenesis of ongoing symptoms after initial treatment should be a clinical research priority. Investigations are also needed into the potential roles of immunologic responses, bacterial persistence, and coinfecting pathogens in order to design and test new therapies and, ultimately, improve outcomes and care for patients with ongoing symptoms.
Americans need help, yet progress has been hampered by a lack of attention at the Federal level and by divisions within the field. The recommendations in this 2018 report of the TickBorne Disease Working Group represent a longterm investment in tackling the rise of tick-borne diseases in this country. However, immediate changes are also required to help patients already suffering from tick-borne diseases; to protect them from discrimination; and to address the inflexible, inconsistent, and often unaffordable care that patients frequently encounter in the current health care system.
Increased Federal funding, prioritization, and leadership are needed to reverse the alarming trends associated with tick-borne diseases.
Despite several decades of research, prevention, and educational activities, Federal funding for tick-borne diseases is less per new surveillance case than that of other diseases. The U.S. National Institutes of Health (NIH) and CDC spend $77,355 and $20,293, respectively, per new surveillance case of HIV/AIDS, and $36,063 and $11,459 per new case of hepatitis C virus, yet only $768 and
$302 for each new case of Lyme disease. Federal funding for tick-borne diseases today is orders of magnitude lower, compared to other public health threats, and it has failed to increase as the problem has grown.
It is also essential that funding and resources be allocated to support a comprehensive, interagency program to address the mounting
challenges identified in this report. All research, prevention, and education initiatives should be inclusive of special populations such as children, who suffer disproportionately from tick-borne diseases. Patients whose lives continue to be disrupted by the lasting effects of these illnesses are counting on emerging scientific research, evidence-based policy, and the health care establishment—including the Federal Government with Congressional and Executive leadership—to provide solutions. We must act now.
November 6, 2018
TickApp featured on ASTMH Annual Meeting Blog
A New App that Allows Researchers to Study Lyme Disease Risks also Documents the Great American Lawn Mowing Divide
By Matthew Davis
ASTMH Annual Meeting 2018 Blog
In their efforts to understand behavioral differences between people in the Northeast and Midwest that can expose them to tick-borne diseases, a team of tick experts from the University of Wisconsin and Columbia University identified one risk factor that doubles as a revealing cultural divide: 60 percent of Wisconsin residents who signed up for their innovative Tick App survey tool reported mowing their own lawn. Only 25 percent of those from New York state identified as self-mowers.
“The lawn mowing difference is still staggering to me,” said Gebbiena Bron, who presented findings Tuesday at TropMed18 of a study that is using the Tick App to look at risk factors influencing human-tick encounters in Lyme disease-endemic areas of the two regions. Thus far, the app has been downloaded by 663 people in the Midwest and 366 people in the Northeast. Users consent to allowing researchers to regularly track their movements. Many also keep a diary and post pictures of ticks they may find on themselves or their pets.
In all seriousness, Bron noted that lawn work may be an under-appreciated risk factor for Lyme disease. She said most people associate tick encounters with being in the woods, but there is increasing evidence of ticks “in your yard.” For example, of the 460 reports of tick encounters fielded thus far, 41 percent of app users from the Midwest and 56 percent from the Northeast believed the encounter occurred in their own yards.
Bron said she and her colleagues from Columbia came up with the idea of the Tick App to address the challenges of observing how human behavior can affect the prevalence of Lyme disease. “We are very difficult animals to study,” she said. But smartphone apps, she said, are proving to be excellent tools for following Homo sapiens.
Thus far, the data collected form the app indicate tick encounter risks are generally higher for people in the Midwest. The app revealed that, in addition to the lawn-moving divide, the Midwestern cohort was more likely to spend time outdoors gardening, camping, hunting and fishing. At the same time, she said the Midwesterners were more likely to do things to reduce the risk of Lyme disease, like wearing protective clothing and regularly checking themselves for ticks.
To translate that finding for a lay audience, Bron said: “The Packers beat the Jets.”
Going forward, Bron said researchers are looking for ways to gather data that can assess the risk level of individual tick encounters “because not all tick encounters are created equal.” For example, researchers would like to know how many involve black-legged ticks, which carry Lyme, or another type, like lone star ticks, which do not.
November 5, 2018
Confirmed human case of St. Louis encephalitis virus reported in a resident of Dane County, Wisconsin
Rare virus unseen in state for 37 years confirmed in Dane County, health officials say
SLEV spread by mosquitoes, DHS says
WISC-TV News 3 Madison
MADISON, Wis. - A confirmed case of a virus that hasn't been reported in Wisconsin in 37 years has been reported, health officials said Thursday.
The Wisconsin Department of Health Services announced Friday that a confirmed human case of St. Louis encephalitis virus, or SLEV, was reported in a resident of Dane County, the first reported case in the state since 1981.
SLEV is related to the West Nile virus, and like West Nile virus, it is spread to people through the bite of an infected mosquito, according to DHS. SLEV is not transmitted person-to-person. The virus is rare in Wisconsin, with only six human cases reported between 1964 and 2018 and no major outbreaks ever reported in the state.
Most people infected with SLEV will not have any symptoms, state health officials said. Those who become ill may develop fever, headache, nausea and fatigue that last for a few days. When symptoms do occur, they typically begin between five and 15 days after being bitten by an infected mosquito. In rare cases, SLEV can cause severe disease with symptoms such as stiff neck, disorientation, tremors, inflammation of the brain and coma. Older adults and people with weakened immune systems are at an increased risk of severe disease from the virus.
There is no specific treatment for SLEV other than to treat symptoms.
Mosquito activity has essentially ended for the year, so there is little to no risk of mosquito-borne illnesses in Wisconsin for a few months. According to the news release, there are several things you can do next spring to minimize your exposure to mosquitoes and eliminate mosquito breeding grounds.
DHS recommended taking the following precautions any time when mosquitoes are active:
- Limit time spent outside at dawn and dusk, when mosquitoes are most active.
- Apply an insect repellent with DEET, IR3535, picaridin or oil of lemon eucalyptus to exposed skin and clothing.
- Make sure window and door screens are in good repair to prevent mosquito entry.
- Prevent mosquitoes from breeding by removing stagnant water from items around your property, such as tin cans, plastic containers, flower pots, discarded tires, roof gutters, and downspouts.
- Turn over wheelbarrows, wading pools, boats and canoes when not in use.
- Change the water in bird baths and pet dishes at least every three days.
- Chlorinate and clean swimming pools, outdoor saunas and hot tubs; drain water from pool covers.
- Landscape to prevent water from pooling in low-lying areas, and trim tall grass, weeds and vines since mosquitoes use these areas to rest during hot daylight hours.
See the original article here.