IPM Voice Newsletter May 2016
Integrated Tick Management Symposium Highlights Need for Action on IPM for Tickborne Diseases
More than 140 scientists, academics, healthcare professionals, policymakers and advocates convened in Washington DC last week to share the latest science on IPM for tickborne diseases. The event served as a call to action to more effectively address this serious health threat.
Tickborne diseases in the US are increasing in number, and ticks and pathogens are spreading geographically. The US Centers for Disease Control currently estimates that over 300,000 people are infected annually with Lyme disease alone, with 37% of those infections being among children. In addition to Lyme, fifteen other diseases found in the US can be vectored by ticks, including Rocky Mountain spotted fever, Babesiosis, Heartland virus, Ehrlichiosis and others, with about 90,000 cases per year.
"Tickborne diseases are increasing and spreading. We have a lot of tools in our toolbox, but we haven't found a single very effective method to manage people's exposure," says Dr. Kirby Stafford, a medical-veterinary entomologist whose specialty is the ecology and control of the blacklegged tick, Ixodes scapularis. Dr. Stafford co-organized the event and is a member of the Tick IPM Working Group. "In the absence of a human vaccine, an integrated approach is really our best option."
"People want economical, effective alternatives," Stafford emphasizes. "Some are better for individual homeowners and others are only an option on a neighborhood/community-wide scale. There are promising technologies that could have an impact such as using rodent bait boxes, rodent vaccines or anti-tick vaccines for deer. Studies have shown fencing and treating deer can have a definite impact."
The current level of public and private investment in research and development, at less than $55 million per year total, with the majority invested in medical interventions, does not match the scale of the threat, which is estimated to exceed $3 billion a year in medical costs and lost productivity. This business case for greater investment was presented by Dr. Thomas Green, president of the IPM Institute of North America, which co-hosted the event. "Tremendous post-infection costs are being borne by the healthcare and health insurance industries, and by employers of those affected by tick-borne diseases," he explained. "These potential partners are not currently broadly engaged in prevention efforts, and public investment is falling short of what's needed to reverse the increase in tick presence and disease incidence. We're still at the very early stages of learning what we need to know about how to use the tools we have, to not only reduce tick populations, but to also reduce infection rates. "
As Dr. Stafford puts it, "Scientific funding is currently very dilute on the federal and state levels. There has to be investment in basic infrastructure and research support if we're going to develop these tools. Otherwise we're going to be using what we already have, and clearly these tools alone are not enough in the face of these diseases increasing. The spread of the disease is really the bottom line."
Dr. Tom Mather, professor of Medical and Veterinary Entomology at the University of Rhode Island and Symposium co-organizer, explained that the conference played an important role in helping attendees view the problem from new angles. "The conference was very useful in that it helped everyone better understand the scope and scale of the problem, and it closed many knowledge gaps. ESA Past-President Phil Mulder made a very astute observation: 'Who is responsible for this problem?' We need to better define what's meant by responsibility - is it legal responsibility, or general capability? Are people at risk from ticks capable of doing what scientists want them to do? More training is needed, with a better understanding of the risks involved. Over recent decades, we've seen a huge erosion of the cooperative extension and county agent model - these were people previously in charge of post-school education in communities, people who could teach citizens how to live with ticks. Ultimately we have ourselves to blame for not supporting this model."
Dr. Ben Beard, associate director for Climate Change and Chief of the Bacterial Diseases Branch of CDC's Division of Vector-Borne Diseases in Fort Collins, Colorado, emphasized that prevention is ultimately the key. "Effective prevention requires the cooperation and collaboration of multiple partners - the burden should not fall on homeowners alone. There are a number of different products and methods in our tool box, including deer control, host-targeted interventions, landscape management and the judicious use of pesticides. In the absence of a human vaccine, the best solutions will likely be IPM methods that have been evaluated across a variety of settings and applied to address the unique local need."
The Symposium concluded with visits to Capitol Hill by multiple participants to educate policymakers and congressional staffers about the scope of the problem. Currently Congress is considering House Bill 789, the Tick-Borne Disease Research Accountability and Transparency Act, and Senate Bill 1503, the Lyme and Tick-Borne Disease Prevention, Education and Research Act. These proposed bills aim to better coordinate federal research and funding against Lyme and other tick-borne diseases.
Dr. Mather reported that many policymakers are aware of the magnitude of the problem, but feel unable to draw adequate support for a funding effort. "They were very attentive - there is great hope we can do a lot to help solve the tick problem in America, but we need to be better supported. It's a tough sell in some cases because it's not perceived as the same huge problem everywhere. Most senators we were talking to were also looking for new ideas, things that could be easier to get passed. They support the basic need to engage people, educate and empower through education. County agents could do that if they were there, for example.
"We brought up that Senators might want to consider greater appropriations via the Smith Lever Act, or targeted competitive grant Requests for Applications, through USDA National Institute for Food and Agriculture for example, that could direct grant money to this whole missing link, which is community based education via on-the-ground experts who can give direct advice on how to live with ticks."
For more on Symposium outcomes, read ESA's follow-up brief. The Symposium was hosted by the Centers for Disease Control and Prevention (CDC), the Entomological Society of America (ESA), the IPM Institute of North America and the North Central IPM Center, with additional support from Evolva, Mainely Ticks, US Biologic and the Tick Box Technology Corporation.
Snails Found to Select Sources of Food Based on Dislike for Smells; Could Open Door to Bio-Based Olfactory Repellents
New research suggests naturally occurring chemicals could be used to protect crop seedlings from slugs and snails, two very common pests to young plants. Researchers at the University of Southampton and Plymouth University examined snail feeding preferences when offered multiple distinct cultivars of oilseed rape seedlings. The research found that snails chose their preferred meal based on scents emitted by certain cultivars rather than by taste. Specifically, the study looked for the presence of glucosinolates and volatile organic chemicals (VOCs), both natural plant defenses of the oilseed rape seedlings. The study found no relationship between glucosinolates and the snails' feeding preferences, but found a strong correlation with the presence of VOCs and the snails' feeding choice. The authors of the study are hopeful this finding could lead to development of bio-based control products with low environmental impact.
A common active ingredient in currently available slug controls is metaldehyde, a molluscicide that has contaminated drinking water in some regions and can be hazardous to birds and other wildlife. As the study authors state, "Crop plants are often bred for various desirable characteristics, but most often priority is given to increased yield and disease resistance over traits favoring herbivore resistance. Increased agro-chemical inputs are often used to maintain productivity; however pesticides can have adverse effects on key non-target species such as pollinators and cause wider contamination. But at a time when increasing demands for food security are in conflict with concern over pesticide use, we show that for one major crop species at least, plant protection could be developed without ecotoxic side effects."
Read more about this research at phys.org.
Scientists Identify New Biocontrol Mechanism: Male-Killing Bacteria to Control Insects
A novel biocontrol mechanism has just been discovered by researchers at the University of California, Riverside. Female insects of a number of species and families including beetles, wasps and butterflies can carry and transmit a bacterium known as Spiroplasma that is lethal to male insects only. In killing males specifically, the bacteria remove male resource competitors and enable the females to survive and spread the bacteria further. Although scientists had theorized that this was accomplished through disruption of underlying developmental processes, the exact cellular and molecular mechanisms by which it occurs had not yet been pinpointed.
According to the research team, the mechanism turns out to be the dosage compensation complex, an epigenetic process that equalizes gene expression in males and females. Since males and females have a different number of genes, the dosage compensation complex is necessary to regulate and equalize the gene traits that are expressed in both sexes. When Spiroplasma attacks the dosage compensation complex, genome-wide misregulation of gene expression occurs and the organism dies. Researchers identified the process and were able to induce it in female fruit flies (
Drosophila melanogaster) that were carrying the bacterium.
This research may carry implications for nonchemical control of fruit fly populations in the future. In particular, researcher Omar Akbari of UC Riverside suggested fruit pest
as a major candidate for control via this technique. To read more about this research, please visit Phys.org
, or read the full text paper in Current Biology
Join IPM Voice!
Renew your IPM Voice membership for 2016 (or become a new member) and check out our donation options by visiting ipmvoice.org/join
Upcoming IPM-Related Meetings and Conferences
University Park, PA
IPM Voice is an independent non-profit organization that seeks to make IPM intelligible and valuable to the world including to the public, the grower community and lawmakers. Our core purpose is to strengthen IPM communities by adding effective communication to the IPM toolbox. IPM Voice was formed in 2010 by more than 35 professionals working to expand the benefits IPM has provided to agriculture and communities for more than 40 years.
IPM Voice, Inc. | 1020 Regent St, Madison WI 53715 | (608) 232-1410 | firstname.lastname@example.org