http://www.poughkeepsiejournal.com/article/20120909/NEWS04/309090038?source=nletter-top5
Tick research lags in war vs. Lyme
Treatment debate overshadows prevention; funding stalls for studies to attack pathogens, diseases
8:46 PM, Sep 9, 2012 |
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Lyme disease study: Taal Levi, a researcher at Cary Institute for Ecosystem Studies, talks about Lyme disease and tick prevalence. Video by Chrissie Williams
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When March Gallagher went looking for a new home, she wanted a place with fewer deer paths, fewer oak trees, fewer acorns, fewer mice. In short, fewer ticks.
The 44-year-old Rosendale resident had been incapacitated by Lyme disease in 2007, and she was determined to head off the tiny biting arachnids, along with the Lyme bacteria and other pathogens they carry.
“Is this property,” she would ask, “going to be tick central?”
Gallagher’s approach — coupled with the use of repellents and body checks — is a smart strategy in the war on Lyme. But it is a war that ticks are winning.
Twenty-five years after the disease rose to prominence, solutions to controlling the spread of ticks and infection remain in an early development stage and, moreover, are disjointed, uncoordinated and underfunded, according to a Poughkeepsie Journal review of funding data and interviews with scientists and advocates.
“What’s the problem? It’s the ticks, of course,” said Jill Auerbach, chairwoman of the Hudson Valley Lyme Disease Association. “There has been little spent on research to reduce their numbers.”
Dutchess, Ulster and three other mid-Hudson Valley counties have the nation’s highest rates of Lyme disease, the most recent federal data show. The number of reported cases in Ulster County increased 48 percent in the five years ending in 2011. The number of cases in Dutchess decreased by 43 percent over the same period, but experts suggest that may be due to reporting fatigue by physicians working in an area where the disease has been endemic for decades.
Today, public health officials are armed with pamphlets, videos and tick-removal kits – their major weapons against Lyme disease. A vaccine? It was pulled from the market. Insecticides? Trials are ongoing, but early results aren’t promising. Research? It’s losing funding — even for work to undermine the ability of tick saliva to defeat a host’s defenses.
And what about the ticks? Methods that seek to hold back tick numbers and infection rates – through better zoning or management of wildlife — are overshadowed by the debate over how to treat the disease. Indeed, the battle to stop the eight-legged menace is flagging.
Grants are rare
In fiscal year 2011, just 18 percent of the nearly 50,000 applications for National Institutes of Health research grants were funded, an all-time low. The approval rate for all National Science Foundation grants was 22 percent in fiscal 2011, also an all-time low.
Competition within those two pools for a research program that specifically studies how ecology affects infectious disease is much fiercer, however. Success rates for these grants have hovered around 10 percent the past six years. This joint NIH and NSF funding category, called Ecology and Evolution of Infectious Diseases, was created in 2000.
The amount of money available for these grants increased steadily in the past decade and peaked at $22.1 million in fiscal 2009, thanks in part to a one-time influx of stimulus money. But since then, it has dropped each year to $14.7 million for fiscal 2011, the lowest in six years.
And while reported cases of Lyme disease nationwide have increased 33 percent from 2001 to 2010, NIH funding for all Lyme disease research grants declined from $25 million in fiscal 2009 to $24 million in fiscal 2010. Funding for Lyme research totaled $28 million in fiscal 2011, and is forecast to remain unchanged in the next two years.
“… (T)here is a massive stopper on our ability to understand these systems because of the lack of funding,” said Taal Levi, an NSF-funded researcher with the Cary Institute of Ecosystem Studies in Millbrook.
An indicator of government’s sluggish response to Lyme disease came at a congressional subcommittee hearing, when U.S. Rep. Chris Smith, R-N.J., welcomed participants to the “first-ever congressional hearing examining the global challenges in diagnosing, treating and managing Lyme disease.”
That was in July.
Debate focuses on treatment
And though attention to Lyme may be increasing, much of the discussion is focusing on treating the disease rather than finding ways to prevent it. The debate over chronic Lyme disease was almost entirely the focus of testimony during the House subcommittee hearing.
The debate over long-term care dominates the discussion even at the local governmental level, where the authority to affect national health-care policy and procedures is limited. At a July 31 forum before the newly formed Ulster County Lyme Disease Advisory Committee, more than a dozen community members who spoke criticized the standards for treatment of the disease — something any county would have almost no say in — and only two addressed concepts aimed at preventing its spread.
The issue of controlling ticks becomes even more urgent when one considers that the tiny arachnids spread not only Lyme, but other infectious diseases such as anaplasmosis and babesiosis, each of which is increasing.
Babesiosis is a potentially life-threatening disease with flu-like symptoms. In the Lower Hudson Valley, cases of babesiosis have increased nearly 20-fold between 2001 and 2008 — from six to 119 — according to a study published in 2011 in the Centers for Disease Control and Prevention journal Emerging Infectious Diseases.
The spread of Lyme into new areas and the corresponding risk of co-infections are worrisome “because residents and health practitioners (in these areas) are unaware of ticks and tick-borne diseases,” said Richard Ostfeld, a disease ecologist with the Cary Institute.
Local governments have focused prevention efforts on education rather than tick eradication. In Dutchess County, more than 10,000 tick-removal kits have been distributed. In 2009, the county conducted a survey to understand what residents know and don’t know about tick-borne diseases, and what the county needs to do about it.
Among its findings: Only 40 percent of those surveyed knew that ticks can cause diseases other than Lyme; about half felt pesticides should be used on public property, such as recreational areas; and 90 percent said there should be more funding for research on how to control ticks.
Ulster’s Lyme advisory committee has been conducting a similar survey this summer. The committee also is boosting its education efforts, including videos and DVDs, leaflets for pet owners at local pet shops, signs with prevention messages at parks and trails and letters to local members of Congress calling for more research funding.
Research lost funding
But while localities struggle to prevent tick bites, measures aimed at defeating the tick’s ability to transmit the disease have been slow in developing. A vaccine was thwarted by issues of cost and controversy. And the increased competition for NIH funding forced a University of Texas scientist to suspend promising research into a way to stop ticks: through their saliva.
Dr. Stephen Wikel spent nearly 40 years peeling apart the complex and insidious dynamics of a tick bite, seeking to characterize what happens immunologically when a tick bites something. Wikel’s research identified a witch’s brew of 500 molecules, some produced and others scavenged from the host, that undermine the host’s defenses.
Wikel identified molecules that inhibit blood clotting, increase blood flow to the site and others that change virtually all aspects of the immune system. Some limit the trafficking of cells from the blood vessels to the site where the tick is feeding, reducing inflammation, an important defense. Others modify wound healing, stop blood-vessel formation and mute pain and itch responses.
“The multitude of things,” Wikel said, “is incredible.”
Wikel’s goal was to develop an immunologic strategy that, instead of targeting the pathogen, would target the molecules in the tick’s spit essential for the establishment of those pathogens.
In October 2010, Wikel’s application for another five years of research funding from the NIH was rejected. Soon after, he closed his lab and accepted a new position at Quinnipiac University.
But the potential for more research is enormous.
“You know that the tick is changing the host environment,” Wikel said, “and if you neutralize the ability to do that, the argument is, you should be able to develop an immunologic strategy — hopefully a vaccine — that would provide protection against a broad range of pathogens that that tick would transmit.”
Vaccine pulled
Such a vaccine would face a long, perilous journey to acceptance. That was the case with Lymerix, the only vaccine approved for Lyme disease.
Lymerix was approved and released in 1998. Fewer than four years later, it was gone. Its maker, SmithKline Beecham (now GlaxoSmithKline), pulled the vaccine from the market, citing declining sales.
Lymerix was dogged by assertions that it caused early onset arthritis and was the subject of a class-action lawsuit. However, a 2001 Federal Drug Administration study found no link between the vaccine and early or late onset arthritis.
“Because of the public perception — and not the vaccine itself — people didn’t buy it,” said Dr. Paul Mead, chief of epidemiology and surveillance activity at the CDC’s Division of Vector-borne Diseases.
Lymerix was pulled from the market in 2002. The class-action lawsuit was settled in 2003, with $1 million in legal fees paid to lawyers but no money awarded to victims.
Mead said Lymerix’s story is a cautionary tale for those seeking a vaccine.
“It’s a process that can be done to great public health benefit overall, but it is a very long and complex process, and there are many pitfalls along the way,” he said.
Mead said the problem with a vaccine is that it protects only those who are vaccinated. Stop the ticks, he said, and you reduce the risk for everybody.
CDC tests insecticide
One way to do that is being tested in Rachel Dildilian’s backyard. The Hyde Park resident lives in one of more than 1,000 households in Dutchess County taking part in a two-year CDC study to assess the benefits of insecticides. Half of the study’s participants receive a single application of bifenthrin, a commercially available pesticide, sprayed along the edges of their property. The other properties are sprayed with water.
Participants are then surveyed throughout the summer to determine whether they have been bitten by ticks or suffered from any tick-borne disease.
“They would call you and say, ‘During the last month, did you see any ticks? Did anybody in your household receive any tick bites? Did your pets get any tick bites?” Dildilian said.
The survey seeks to determine whether spraying insecticides actually reduces the incidence of tick-borne diseases.
It is also being conducted at households in Maryland and Connecticut.
Mead said data are still being collected and analyzed, but early indications are that the number of Lyme disease cases hasn’t dropped.
If that trend continues, “then we really need to redouble our efforts looking for something different,” Mead said.
The CDC also is conducting a study in Connecticut that uses bait boxes to attract mice, which are then coated with an insecticide. Mice contain the Lyme disease bacteria, carry lots of ticks and have fewer predators due to human development.
Better planning helps
Indeed, many experts think the most effective way to limit Lyme is the most time-consuming and the hardest to sell to the public — that is, to restore ecological conditions that keep the disease in check.
Ostfeld, the disease ecologist at the Cary Institute, has long argued that forest fragments — small chunks of wooded land left over after development — create habitats that are devoid of the predators that feed on mice and other small mammals.
“… (T)here are wildlife species out there in the woods that are helping us a lot,” Ostfeld said. “So the question then becomes, what do we do to help them do their job?”
The answer, some say, is better planning. The Dutchess County planning department has begun highlighting the importance of biodiversity. The goal is to encourage larger swaths of undisturbed, contiguous natural space that allow for a greater array of wildlife, particularly predators that prey upon small rodents.
County planners admit that disease ecology rarely comes up as a topic at municipal zoning board meetings. Bob Wills, a senior mapping project coordinator, said he mapped 12 years’ worth of Lyme disease cases with data provided by the Dutchess County Health Department. Wills said he found a strong correlation between where people were getting the disease and the proximity of forest fragments.
“Our zoning,” Dutchess development and design coordinator John Clarke said, “is leading to this health crisis.”
New York’s constitution puts planning authority in the hands of cities, towns and villages.
Since disease ecology is not confined to town borders, planning needs to be regional.
While other states allow for regional planning authorities, New York’s county and regional planners can advise, but not compel.
The best approach, Clarke said, is when communities work together to establish zoning techniques that encourage development in town and village centers and preserve large, biologically diverse blocks of land.
The solutions can’t come fast enough for people like Gallagher, the Rosendale resident.
In the years she battled the disease, Gallagher quit her job at the Ulster County Industrial Development Agency. She shut her law practice.
She stopped volunteering.
“I couldn’t work. I couldn’t drive. I couldn’t parent,” she said.
Her home in Rosendale abuts the New York State Thruway, a position that limits the ability of deer to enter her property. There are far fewer oak trees than there were at her previous home, meaning fewer acorns to support mice and other small mammals.
She read about how to manage landscaping to reduce leaf litter, under which ticks hide. She bought guinea fowl, who like to dine on ticks. She sprayed her yard with beneficial nematodes, tiny roundworms that can enter a tick through its anal pore and release a deadly bacterium.
Many of these techniques are still being studied. In the meantime, Gallagher has had to figure out the best approaches on her own.
“I had to,” she said. “I had to.”
