Heartland Virus Neutralizing Antibodies in U.S. Vertebrate Wildlife 2009–2014

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RitaA
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Heartland Virus Neutralizing Antibodies in U.S. Vertebrate Wildlife 2009–2014

Post by RitaA » Sun 20 Sep 2015 5:57

http://wwwnc.cdc.gov/eid/article/21/10/15-0380_article
Volume 21, Number 10—October 2015
Dispatch

Heartland Virus Neutralizing Antibodies in Vertebrate Wildlife, United States, 2009–2014

Kasen K. Riemersma1 and Nicholas Komar
Author affiliations: Centers for Disease Control and Prevention, Fort Collins, Colorado, USA

Abstract

Since its discovery in 2009, the tickborne Heartland virus (HRTV) has caused human illness in Missouri, Oklahoma, and Tennessee USA. To better assess the geographic distribution of HRTV, we used wildlife serology as an indicator. This retrospective evaluation determined that HRTV is widespread within the central and eastern United States.


Heartland virus (HRTV; family Bunyaviridae, genus Phlebovirus) is an emerging public health threat in the United States. HRTV disease, characterized by severe fever, leukopenia, and thrombocytopenia, was first reported in 2 farmers in northwestern Missouri in 2009 (1). Seven additional HRTV disease cases (2 fatal) have been reported in Missouri, Tennessee, and Oklahoma (2,3). A study of ticks and mosquitoes in northwestern Missouri detected HRTV infections only in Amblyomma americanum (lone star tick) and thus implicated this tick as a vector (4). The virus was isolated solely from deplete host-seeking nymphs, which presumably were infected as larvae after feeding on a viremic vertebrate host. Because HRTV has yet to be isolated from any wild or domestic animals, the question of vertebrate reservoir(s) remains unanswered. However, high prevalence of seropositive white-tailed deer (Odocoileus virginianus) and raccoon (Procyon lotor) from northwestern Missouri indicate these species as targets for wildlife serosurveillance (5).

The HRTV disease case reports in Tennessee and Oklahoma after the initial case reports in Missouri create the perception that HRTV transmission activity might be dispersing from an origin in northwestern Missouri. However, the geographic range of HRTV activity is unknown. HRTV distribution may mirror the range of the lone star tick, which is distributed throughout most of the central and eastern United States and recently has expanded northward (6). To investigate the hypothesis that HRTV activity occurs throughout the range of its putative tick vector, we conducted a retrospective serosurvey of mainly white-tailed deer and raccoon from 19 states within the heart and periphery of the lone star tick range to look for evidence of HRTV activity.

The Study

Banked blood samples collected from white-tailed deer, raccoon, and (occasionally) moose (Alces alces) and coyote (Canis latrans) during 2009–2014 were analyzed by plaque-reduction neutralization test for HRTV neutralizing antibodies by using African green monkey kidney (Vero) cell culture. Only samples from healthy live-trapped animals or deceased animals from anthropogenic causes (i.e., hunting, culls, and automobile strikes) were tested. Inclusion of 19 states was opportunistic based on sample availability. We used the plaque-reduction neutralization test to evaluate HRTV seropositivity for white-tailed deer (n = 396), raccoon (n = 949), coyote (n = 61), and moose (n = 22) (Table 1). Samples consisted of whole blood dried onto Nobuto strips (Advantec MFS, Inc., Dublin, CA, USA), bloody body cavity fluids, or hemolyzed whole blood. Nobuto strip samples were eluted to 1:10 serum dilution in phosphate buffer solution in accordance with the manufacturer’s instructions. All samples were heat-inactivated at 56°C for 45 min.

We screened the inactivated samples at 1:20 dilution by mixing serum diluted 1:10 with equal volume of titrated HRTV to approximate a challenge dose of 50 PFUs. Treated Vero cells were incubated for 1 h at 37°C, 5% CO2, before applying a nutrient-rich 0.5% agarose overlay. A second overlay containing Neutral Red was applied after 5–7 d of incubation. Viral plaques were counted 6–12 d after inoculation. A neutralization threshold of 70% relative to HRTV-only controls was used to determine positive samples. All screen-positive samples were repeat-tested to confirm results. Samples were considered seropositive if they were confirmed as positive at a dilution of >1:40. Comparative neutralization tests with related viruses were not performed, because we had previously found that murine antiserum developed against the other known phleboviruses in the United States—Sunday Canyon virus (7), Rio Grande virus (8), and Lone Star virus (9)—had no appreciable neutralizing activity against HRTV (Table 2). Human antiserum developed against HRTV exhibited weak 1-way neutralization of Lone Star virus and Sunday Canyon virus (Table 2).

Of 1,428 animals, 103 were seropositive: 55 deer, 33 raccoon, 11 coyotes, and 4 moose. Thirteen states had seropositive animals: Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Maine, Missouri, New Hampshire, North Carolina, Tennessee, Texas, and Vermont (Table 1; Figure 1). Within the 13 states, 20 geographic clusters of seropositive animals were mapped by plotting positive animals by the county where they were collected (Figure 2).

Conclusions

We provide evidence of widespread HRTV transmission activity across the central and eastern United States. Of 13 affected states, only Missouri and Tennessee had previous evidence of HRTV activity. A more stringent neutralization threshold of 80% would reclassify 14 positive samples to “equivocal,” but the number of positive states would remain unchanged. These findings should encourage clinicians and public health officials to consider HRTV as a potential source of illness throughout the eastern United States.

Surprisingly, seropositive white-tailed deer were detected in northern New England, where established populations of lone star ticks are unknown (6). Possible explanations include unreported lone star tick populations, immigration of seropositive deer, alternative tick vectors for HRTV, or presence of a serologically cross-reactive virus. Movement of deer across state boundaries is an unlikely explanation. Extensive lone star tick populations are not reported in neighboring states (6), and migration of deer from lone star tick–infested regions is unlikely (10). Savage et al. did not detect HRTV RNA in Dermacentor variabilis, the American dog tick (4), but additional tick species inhabit northern New England. Several tick species are reported to transmit severe fever with thrombocytopenia syndrome virus, a closely related phlebovirus found in eastern Asia (11). Further investigation of tick populations and their vector competence for HRTV is warranted, and production of HRTV neutralizing antibodies in response to a serologically similar virus should be investigated. Two new phleboviruses recently detected in Ixodes ticks in the northeastern United States are genetically unrelated to HRTV but raise the possibility that additional undiscovered phleboviruses exist (12). Severe fever with thrombocytopenia syndrome virus–reactive antibodies in wildlife were reported in Minnesota, also peripheral to the lone star tick geographic range, indicating the likely presence of HRTV or a similar virus there (13).

The finding of seropositive moose and coyotes indicates that these mammals are exposed to HRTV in certain situations and might be useful targets for serosurveillance, in addition to deer and raccoon. The full vertebrate host range and the reservoir competence of these mammals for HRTV remains unknown.

The chronology of dispersal of HRTV is unclear. Suggesting that HRTV emerged in northwestern Missouri and spread to neighboring states to the east and south is overly simplistic. Because animals were sampled at different points of time and space during this study, our data lack robustness to enable comparison of populations over time or between geographic locations. Thus, we are unable to evaluate the dynamics of HRTV spread. Furthermore, the proportions of HRTV-seropositive animal populations lack quantitative value because of our retrospective convenience sampling. Our results simply indicate that HRTV or a very similar virus has circulated in the sampled regions in the recent past and that this activity began as early as 2009. Adult seropositive white-tailed deer were detected in Maine and Florida in 2009, and based on the estimated ages of affected deer (data not shown), the infections could have occurred as early as 2003. A much larger retrospective serosurvey is necessary to elucidate HRTV’s history of emergence.

Dr. Riemersma was a veterinary student in the CDC Epidemiology Elective program at the Division of Vector-Borne Diseases during this study and is currently a PhD student at the University of California, Davis. His research interests include the genetics and ecology of pathogen emergence, with particular interest in vector-borne viruses.

Dr. Komar is the vertebrate ecologist for the Arbovirus Diseases Branch, Division of Vector-Borne Diseases, CDC, Fort Collins, Colorado. His major research interest is the role of vertebrate hosts in arbovirus transmission cycles.

[snip]

This study was supported by the CDC Epidemiology Elective Program and funded by CDC.

References

McMullan LK, Folk SM, Kelly AJ, MacNeil A, Goldsmith CS, Metcalfe MG, A new phlebovirus associated with severe febrile illness in Missouri. N Engl J Med. 2012;367:834–41.
Pastula DM, Turabelidze G, Yates KF, Jones TF, Lambert AJ, Panella AJ, Notes from the field: Heartland virus disease—United States, 2012–2013.[PubMed]. MMWR Morb Mortal Wkly Rep. 2014;63:270–1.
Oklahoma State Department of Health. Oklahoma State Health Department confirms first case and death of Heartland virus [cited 2014 Jul 2].http://www.ok.gov/health/Organization/O ... Virus.html
Savage HM, Godsey MS, Lambert A, Panella NA, Burkhalter KL, Harmon JR, First detection of Heartland virus (Bunyaviridae: Phlebovirus) from field-collected arthropods. Am J Trop Med Hyg. 2013;89:445–52.
Bosco-Lauth AM, Panella NA, Root JJ, Gidlewski T, Lash RR, Harmon JR, Serological investigations of Heartland virus (Bunyaviridae: Phlebovirus) exposure in wild and domestic animals adjacent to human case sites in Missouri 2012–2013. Am J Trop Med Hyg. 2015;92:1163–7.
Springer YP, Eisen L, Beati L, James AM, Eisen RJ. Spatial distribution of counties in the continental United States with records of occurrence of Amblyomma americanum (Ixodida: Ixodidae). J Med Entomol. 2014;51:342–51. Yunker CE, Clifford CM, Thomas LA, Keirans JE, Casals J, George JE, Sunday Canyon virus, a new ungrouped agent from the tick Argas (A.) cooleyi in Texas. [PubMed]. Acta Virol. 1977;21:36–44.
Calisher CH, McLean RG, Smith GC, Szmyd DM, Muth DJ, Lazuick JS. Rio Grande—a new phlebotomus fever group virus from south Texas.[PubMed]. Am J Trop Med Hyg. 1977;26:997–1002.
Swei A, Russell BJ, Naccache SN, Kabre B, Veeraraghavan N, Pilgard MA, The genome sequence of lone star virus, a highly divergent bunyavirus found in the Amblyomma americanum tick. PLoS ONE. 2013;8:e62083.
Lesage L, Crête M, Huot J, Dumont A, Ouellet J-P. Seasonal home range size and philopatry in two northern white-tailed deer populations. Can J Zool. 2000;78:1930–40 .
Yun S-M, Lee W-G, Ryou J, Yang S-C, Park S-W, Roh JY, Severe fever with thrombocytopenia syndrome virus in ticks collected from humans, South Korea, 2013. [PubMed]. Emerg Infect Dis. 2014;20:1358–61.
Tokarz R, Williams SH, Sameroff S, Sanchez Leon M, Jain K, Lipkin WI. Virome analysis of Amblyomma americanum, Dermacentor variabilis, andIxodes scapularis ticks reveals novel highly divergent vertebrate and invertebrate viruses. J Virol. 2014;88:11480–92.
Xing Z, Schefers J, Schwabenlander M, Jiao Y, Liang M, Qi X, Novel bunyavirus in domestic and captive farmed animals, Minnesota, USA. Emerg Infect Dis. 2013;19:1487–9.
http://news.sciencemag.org/health/2015/ ... astern-u-s
The Heartland virus may occur across the eastern U.S.

By Martin Enserink 18 September 2015 2:30 pm

A dangerous tick-borne virus that first surfaced in humans in Missouri in 2009 appears to be common in wildlife across the central and eastern United States, according to a new study. Researchers at the Centers for Disease Control and Prevention (CDC) in Fort Collins, Colorado, found evidence of the so-called Heartland virus in deer, raccoons, coyotes, and moose in 13 states. Doctors should be on the lookout for human patients, the researchers say, because they might go undetected. But other researchers say such warnings are premature.

The first known human cases of the Heartland virus were two farmers in northwestern Missouri. Both became very sick in 2009, with symptoms including fever, fatigue, headache, lack of appetite, nausea, and diarrhea. Both had also recently been bitten by ticks, but tests for the usual tick-borne suspects—such as several Ehrlichia species, a group of intracellular bacteria—came back negative. Both patients recovered, although one of them kept suffering from fatigue and headaches.

It wasn't until 3 years later, in 2012, that scientists reported that the patients had most likely been infected by a hitherto unknown agent. The virus, named after the Heartland Regional Medical Center in St. Joseph, Missouri, where the farmers had been treated, is a species of the genus Phlebovirus. That group also includes the mosquito-borne Rift Valley fever virus and several other agents linked to human disease.

Since then, seven more Heartland cases—including two fatal ones—have been reported in Missouri, Tennessee, and Oklahoma, and researchers have begun to unravel the virus's ecology and geographical spread. For a study published in 2013, they collected more than 50,000 ticks at the Missouri farms and elsewhere in the region; they found that the lone star tick, Amblyomma americanum, was the only species carrying the virus and thus most likely the culprit. Another study in northwestern Missouri, published last year, fingered white-tailed deer and raccoons as likely hosts for the virus. Ticks probably feed on these animals as tiny larvae in the late summer and fall, they concluded, and infect humans during the following spring and summer when they're nymphs.

In the new study, CDC's Nicholas Komar and Kasen Riemersma—who's now at the University of California, Davis—used existing blood samples from white-tailed deer, raccoons, moose, and coyotes collected between 2009 and 2014 in 19 states, both in the center of the lone star tick's range and its periphery, and tested them for antibodies against the Heartland virus. Out of 1428 animals, 103 tested positive, the researchers report in a paper posted this week in Emerging Infectious Diseases: 55 deer, 33 raccoons, 11 coyotes, and four moose.

The positive samples came from 20 geographical clusters spread out over 13 different states, from Maine to Texas. "These findings should encourage clinicians and public health officials to consider [Heartland virus] as a potential source of illness throughout the eastern United States," the duo writes.

But not everyone is convinced. The lone star tick doesn't occur in northern New England, so it's not clear why the Heartland virus would circulate there, says medical entomologist Durland Fish, a professor emeritus at Yale University. It may well be that the antibodies found by the team weren't directed against the Heartland virus but some other agent; it's not uncommon for cross-reactivity to occur in serological tests. In fact, Fish isn't convinced that the Heartland virus is tick-borne; the fact that it was found in ticks doesn't mean they also transmit the virus, he says. "The whole thing is very speculative.”

Komar acknowledges that the team was surprised to find evidence of the virus outside the lone star tick's range. There could be another tick species acting as host in the northern United States, he says. It's also possible that the antibodies were directed against another virus, as Fish suggests, he acknowledges—but if so, it would be a closely related and unknown phlebovirus, which still would be something to watch closely. "We wanted to raise awareness about this in the medical community," Komar says. But Fish says it's too early for that. "There's enough paranoia about tick-borne diseases out there right now.”
The Lone Star tick's range may well be expanding. To what extent has yet to be determined:

http://www.ncbi.nlm.nih.gov/pubmed/24724282
J Med Entomol. 2014 Mar;51(2):342-51.

Spatial distribution of counties in the continental United States with records of occurrence of Amblyomma americanum (Ixodida: Ixodidae).

Springer YP, Eisen L, Beati L, James AM, Eisen RJ.

Abstract

In addition to being a major nuisance biter, the lone star tick, Amblyomma americanum (L.), is increasingly recognized as an important vector of pathogens affecting humans, domestic animals, and wildlife. Despite its notoriety, efforts have been lacking to define the spatial occurrence ofA. americanum in the continental United States with precision beyond that conveyed in continental-scale distribution maps. Here we present a county-level distribution map for A. americanum generated by compiling collection records obtained from a search of the published literature and databases managed by the USDA, U.S. National Tick Collection, and Walter Reed Biosystematics Unit. Our decadal and cumulative maps, which visually summarize 18,121 collections made between 1898 and 2012, show that A. americanum is either established (> or = six ticks or -two life stages) or reported (<six ticks of a single life stage or number of ticks not specified) in 1,300 counties distributed among 39 states and the District of Columbia. Our cumulative map depicts a species with a core distributional area in the southern part of the eastern United States, but that also occurs further north, especially along the Atlantic Coast and into the Midwest. Although our decadal maps suggest a northward shift in the tick's distribution in recent decades, the lack of systematic tick surveillance makes this difficult to confirm. The data presented herein should aid in identifying areas posing risk for A. americanum-associated illnesses and environmental correlates that define the tick's distributional limits.

PMID:
24724282
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/pubmed/26217042
Am J Trop Med Hyg. 2015 Jul 27. pii: 15-0330. [Epub ahead of print]

Modeling the Present and Future Geographic Distribution of the Lone Star Tick, Amblyomma americanum (Ixodida: Ixodidae), in the Continental United States.

Springer YP1, Jarnevich CS2, Barnett DT2, Monaghan AJ2, Eisen RJ2.

Author information

1 Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado; U.S. Geological Survey, Fort Collins, Colorado; National Ecological Observatory Network, Inc., Boulder, Colorado; National Center for Atmospheric Research, Boulder, Colorado
2 Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado; U.S. Geological Survey, Fort Collins, Colorado; National Ecological Observatory Network, Inc., Boulder, Colorado; National Center for Atmospheric Research, Boulder, Colorado.

Abstract

The Lone star tick (Amblyomma americanum L.) is the primary vector for pathogens of significant public health importance in North America, yet relatively little is known about its current and potential future distribution. Building on a published summary of tick collection records, we used an ensemble modeling approach to predict the present-day and future distribution of climatically suitable habitat for establishment of the Lone star tick within the continental United States. Of the nine climatic predictor variables included in our five present-day models, average vapor pressure in July was by far the most important determinant of suitable habitat. The present-day ensemble model predicted an essentially contiguous distribution of suitable habitat extending to the Atlantic coast east of the 100th western meridian and south of the 40th northern parallel, but excluding a high elevation region associated with the Appalachian Mountains. Future ensemble predictions for 2061-2080 forecasted a stable western range limit, northward expansion of suitable habitat into the Upper Midwest and western Pennsylvania, and range contraction along portions of the Gulf coast and the lower Mississippi river valley. These findings are informative for raising awareness of A. americanum-transmitted pathogens in areas where the Lone Star tick has recently or may become established.

© The American Society of Tropical Medicine and Hygiene.

PMID:
26217042
[PubMed - as supplied by publisher]

http://www.mvtimes.com/2015/05/27/marth ... illnesses/
Martha’s Vineyard hits peak time for tickborne illnesses

by Barry Stringfellow - May 27, 2015

[snip]

This year, there’s a buzz about a new bad guy in town — the Lone Star tick.

Lone Star rides into town

While it’s premature to say if the Lone Star tick has colonized on the Vineyard, anecdotally and on social media, many Islanders have reported finding them for the first time this year.

The Lone Star tick has been on Martha’s Vineyard in small numbers for some time, according to Mr. Telford. It’s had a mysterious presence. “I’ve seen them here as early as the late ’90s, and I found them in Nantucket in the late ’80s,” he said. “But they fizzle. Why is that? On Prudence Island in Narragansett Bay they’ve been around since the 1960s, and [people] have a horrible problem with them. But you don’t see them on Bristol or any of the nearby islands. It’s a huge mystery.”

Unlike deer ticks and dog ticks, the Lone Star tick is an aggressive predator. “They’re nasty; they have eyes, unlike deer ticks that are blind,” Mr. Telford said. “They can see you and come after you.”

The female Lone Star tick is often distinguished by the white “star” on its back; however, not all Lone Star ticks have the white spot. “All, however, are round and brown,” Mr. Telford said. “All move fast.”

Until recently, the Lone Star tick was primarily found south of the Mason-Dixon Line. But as the climate has warmed, the infectious insect has spread its range.

The Lone Star tick has now colonized on Cuttyhunk, Nashawena, and Prudence Island.

Mr.Telford said that he discovered the Lone Star tick infestation on Cuttyhunk five years ago. “People were raising the flag, saying there are no Lone Star ticks in Massachusetts, but then I went to Cuttyhunk to give a talk, and said, ‘We’ve got a problem here.’”

The Lone Star tick is a vector for Rocky Mountain spotted fever as well as tularemia, ehrlichiosis, and Masters’ disease. Rocky Mountain spotted fever symptoms include nausea, vomiting, high fever, chills, muscle aches, insomnia, and a red, non-itchy rash that usually appears on wrists and ankles, and spreads in both directions. According to the Columbia University Lyme and Tick Borne Disease research center, about 3 percent to 5 percent of patients who are infected with Rocky Mountain spotted fever will die from it. The telltale rash will show up in five to 10 days, but 10 to 15 percent of those infected never get the rash.

“It’s not just diseases you can get from Lone Star ticks; for some reason, some people develop an allergy to red meat,” Mr. Telford said, citing a recent connection made by a study at the University of Virginia Medical School.

Action imperative

Mr. Telford stressed preventive measures have to be taken immediately so Martha’s Vineyard doesn’t become rife with Lone Star ticks. “We think this should be nipped in the bud,” he said. “Let’s not talk about it, let’s not research it anymore, let’s just follow up on the reports, and go to the site and investigate. This is a way citizens can get involved to prevent the problem.”

[snip] “If it’s a homeowner, we’ll see if it’s OK to spray pesticide,” Mr. Telford said. “If it’s conservation land, we’ll find some way to get rid of them. If you get volunteers and drag the area day after day, you can get rid of them.”

[snip]

Mr. Telford [says] “The deer tick female lays 2,000 eggs. The Lone Star tick lays 6,000 eggs, so it doesn’t take long to build up a population,” he said. “Let’s do something about this while we can.”
Last edited by RitaA on Sun 20 Sep 2015 18:33, edited 1 time in total.

RitaA
Posts: 2768
Joined: Thu 1 Jul 2010 8:33

Re: Heartland Virus Neutralizing Antibodies in U.S. Vertebrate Wildlife 2009–2014

Post by RitaA » Sun 20 Sep 2015 6:14

From a couple of years ago:

http://www.prnewswire.com/news-releases ... 93231.html
WESTBROOK, Maine, June 18, 2013 /PRNewswire/ -- Historically considered a southern and south-central parasite, the lone star tick is progressively expanding northward and eastward, creating new concerns for pets and people in these areas of the country. This tick, known for the white, star-like spot on the back of the female, is an aggressive biter and can transmit pathogen diseases to dogs, cats and people.

"Lone star ticks become more and more widespread every year, as they continue to infiltrate states where they have never before been present," said Michael Dryden, DVM, PhD, distinguished professor of veterinary parasitology at Kansas State University College of Veterinary Medicine, who is considered one of the nation's foremost authorities on ticks that infect dogs and cats.

New data shows viable lone star tick populations today as far north as New York, Maine – even Ontario, Canada – and as far west as Nebraska. Traditionally found in southeastern and south-central states such as Texas, Oklahoma, Missouri, Arkansas, Georgia, Florida and the Carolinas, the lone star tick now can be found throughout the northeast and north-central region in places like Iowa, Illinois, Indiana, Wisconsin, Michigan and Pennsylvania.

"The lone star tick is a very aggressive tick, and it actively seeks out people and pets to feed on," said Michael J. Yabsley, MS, PhD, F.R.E.S, associate professor at the Warnell School of Forestry and Natural Resources and the Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine at The University of Georgia. "It's one of the most common ticks that people find on themselves and their dogs, so everyone should take precautions – especially in the new areas of invasion."

[snip]

RitaA
Posts: 2768
Joined: Thu 1 Jul 2010 8:33

Re: Heartland Virus Neutralizing Antibodies in U.S. Vertebrate Wildlife 2009–2014

Post by RitaA » Tue 22 Sep 2015 8:08

http://www.npr.org/sections/health-shot ... ts-thought
Public Health

Deadly Heartland Virus Is Much More Common Than Scientists Thought

September 16, 2015 1:52 PM ET

It's called the Heartland virus disease. Since it was first detected in 2009, there have been only nine reported cases in the Midwest, including two deaths.

So scientists thought the Heartland virus was limited to a small region.

That assumption was wrong.

A team at the Centers for Disease Control and Prevention has now found signs that Heartland virus is circulating in deer, raccoons, coyotes and moose in 13 states — from Texas to North Carolina and Florida to Maine.

"It was not only in these states, but it was fairly common," says biologist Nick Komar, who led the study. "It's very possible there have been many other cases that have been overlooked."

The Heartland virus causes symptoms similar to other diseases, including high fever, nausea, joint pain and severe bruising.

"Unless doctors are doing laboratory tests specifically for this infection, they'll miss it," Komar says. "This study is a way to get the word out, so the medical establishment knows there may be more infections out there. And people should be watching for it."

Komar and his colleague looked for signs of previous Heartland infections in about 1,400 animals in 17 states. About 100 animals tested positive for Heartland antibodies, Komar and his colleague report Wednesday in the journal Emerging Infectious Diseases.

Since the study didn't directly detect the Heartland virus in the animals, there's a small chance another virus very similar to Heartland is circulating in some states, Komar says.

"The underlying message of this story is there are new pathogens out there," he says. "Our society is changing so quickly — and even the climate — that it allows for new things to develop. And we have to be on the lookout for those new things so we can protect the public health."

Scientists thought the lone star tick was the primary way Heartland spreads. But that tick isn't found up in northern New England. So there's likely a second type of tick that can also carry Heartland.
I have no idea how medical professionals are expected to know which infection(s) to suspect and which test(s) to order when a patient comes in with symptoms that could be caused by any number of viral or bacterial infections -- or something else entirely.

Edited to add:

In response to my comment above, books like the following might help, but how often are they updated to include newly-discovered infections?

http://www.medicalmediareview.com/diffe ... ases-1996/
Book Review: Differential Diagnosis of Infectious Diseases

By Mark Yoffe, MD | 3 December, 2012

Differential Diagnosis of Infectious Diseases (1996) by David Schlossberg MD is one of those rare let-me-try-to-tell-you-in-350-pages-or-less-everything-I’ve-ever-learned-in-a-lifetime-of-clinical-practice types of medical books.

Unlike most microbiology and infectious diseases books, which are organized on the basis of bugs or diseases, Differential Diagnosis is arranged on the basis of specific clinical problems or chief complaints (fever, pneumonitis, diarrhea, rash, arthritis or lymphadenopathy). This is a superior arrangement because it reflects the way in which clinicians approach problems in the real world.

The book helps the reader tease apart various pathogens on the basis of the patient history and physical examination. Classic associations (tularemia with rabbits, psittacosis with birds, etc.) are all listed in tables, as are the important clinical signs and diagnostic methods for the more bread-and-butter bugs. Finally, and perhaps most importantly, the book contains entries which alert the reader about noninfectious diseases that can mimic infectious diseases. For example, the author lists eosinophilic pneumonia and pulmonary embolism as possible mimickers of acute infectious pneumonitis. This reinforces the important concept that every doctor, even a specialist, is a generalist first and needs to be aware of diagnostic possibilities that, technically speaking, could be considered to fall outside to the province of his or her specialty.
Edited again to add:

Here's another tool that may prove useful for medical professionals:

http://www.iddx.com/
IDdx: Infectious Disease Queries

Decision-Support Software for Infectious Diseases

IDdx is a decision-support software tool developed to assist in the diagnosis of infectious diseases. Having a software tool is not the same as having an infectious disease specialist with years of education and years of experience diagnosing infectious diseases. IDdx is like an electronic book that you can query. It is not designed to replace the human mind, but to help the professional with lists and intersections of lists.

[snip]

lou
Posts: 215
Joined: Fri 2 Nov 2007 0:41

Re: Heartland Virus Neutralizing Antibodies in U.S. Vertebrate Wildlife 2009–2014

Post by lou » Fri 25 Sep 2015 23:21

The extent to which Durland Fish will go to deny any kind of tick related new information is breathtaking. Dr. No should be his nickname. We will never get any help from people like this. His PhD should be taken away. He is no scientist.

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