Archive for the ‘research’ Category

Study Finds ‘No Significant Beneficial Effect’ of Restrictive Lockdowns

https://onlinelibrary.wiley.com/doi/epdf/10.1111/eci.13484

Abstract
Background and Aims: The most restrictive non-pharmaceutical interventions (NPIs) for controlling
the spread of COVID-19 are mandatory stay-at-home and business closures. Given the consequences
of these policies, it is important to assess their effects. We evaluate the effects on epidemic case
growth of more restrictive NPIs (mrNPIs), above and beyond those of less restrictive NPIs (lrNPIs).
Methods: We first estimate COVID-19 case growth in relation to any NPI implementation in
subnational regions of 10 countries:
  • England
  • France
  • Germany
  • Iran
  • Italy
  • Netherlands
  • Spain
  • South Korea
  • Sweden
  • US

Using first-difference models with fixed effects, we isolate the effects of mrNPIs by subtracting the combined effects of lrNPIs and epidemic dynamics from all NPIs. We use case growth in Sweden and South Korea, two countries that did not implement mandatory stay-at-home and business closures, as comparison countries for the other 8 countries (16 total comparisons).

Results: Implementing any NPIs was associated with significant reductions in case growth in 9 out of
10 study countries, including South Korea and Sweden that implemented only lrNPIs (Spain had a
non-significant effect). After subtracting the epidemic and lrNPI effects, we find no clear, significant
beneficial effect of mrNPIs on case growth in any country. In France, e.g., the effect of mrNPIs was
+7% (95CI -5%-19%) when compared with Sweden, and +13% (-12%-38%) when compared with
South Korea (positive means pro-contagion). The 95% confidence intervals excluded 30% declines in
all 16 comparisons and 15% declines in 11/16 comparisons.
Conclusions: While small benefits cannot be excluded, we do not find significant benefits on case
growth of more restrictive NPIs. Similar reductions in case growth may be achievable with less
restrictive interventions.
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**Comment**
We can be very thankful Sweden and South Korea stood up to the concerted bullying or there would have been no control group to compare lockdowns to!

Category:

Activism, research, Viruses

Spatial and Temporal Patterns of Borrelia Miyamotoi in NY Deer Ticks

https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-020-04569-2

Spatial and temporal patterns of the emerging tick-borne pathogen Borrelia miyamotoi in blacklegged ticks (Ixodes scapularis) in New York

Parasites & Vectors volume 14, Article number: 51 (2021) Cite this article

Abstract

Borrelia miyamotoi, a bacterium that causes relapsing fever, is found in ixodid ticks throughout the northern hemisphere. The first cases of human infection with B. miyamotoi were identified in 2011. In the eastern USA, blacklegged ticks (Ixodes scapularis) become infected by feeding on an infected vertebrate host, or through transovarial transmission. We surveyed B. miyamotoi prevalence in ticks within forested habitats in Dutchess County, New York, and identified possible reservoir hosts. To assess spatial variation in infection, we collected questing nymphal ticks at > 150 sites. To assess temporal variation in infection, we collected questing nymphs for 8 years at a single study site. We collected questing larval ticks from nine plots to estimate the amount of transovarial transmission. To evaluate potential reservoir hosts, we captured 14 species of mammal and bird hosts naturally infested with larval blacklegged ticks and held these hosts in the laboratory until ticks fed to repletion and molted to nymphs. We determined infection for all ticks using quantitative polymerase chain reaction.

  • The overall infection prevalence of questing nymphal ticks across all sites was ~ 1%, but prevalence at individual sites was as high as 9.1%.
  • We detected no significant increase in infection through time.
  • Only 0.4% of questing larval ticks were infected.
  • Ticks having fed as larvae from short-tailed shrews, red squirrels, and opossums tended to have higher infection prevalence than did ticks having fed on other hosts.

Further studies of the role of hosts in transmission are warranted. The locally high prevalence of B. miyamotoi in the New York/New England landscape suggests the importance of vigilance by health practitioners and the public.

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**Comment**

A perfect example of how there can be high infection rates in humans but low infection rates in ticks.

Category:

Borrelia Miyamotoi (Relapsing Fever Group), research, Testing, Ticks

Herxheimer Reaction in 13 Year Old Boy With Lyme Disease

https://danielcameronmd.com/herxheimer-reaction-lyme-disease/

HERXHEIMER REACTION IN A 13-YEAR-OLD BOY WITH LYME DISEASE

herxheimer reaction in boy with lyme disease

A Jarisch-Herxheimer reaction (JHR), also referred to as a Herxheimer reaction, was first described after initiating treatment for syphilis. This reaction is associated with the onset of new symptoms or a worsening of existing symptoms in patients receiving antibiotic treatment. The Herxheimer reaction has also been described in patients treated for leptospirosis, relapsing fever, and Lyme disease.

By

In a recently published paper, Nykytyuk and colleagues describe the case of a 13-year-old boy with Lyme arthritis, a common manifestation of Lyme disease, who developed a Herxheimer reaction when treated with doxycycline. [1]

“A 13-year-old boy was admitted to the regional hospital with complaints of left knee swelling, hip, ankle and cervical spine pain,” the authors write. The first signs of left knee arthritis began 6 months prior to his hospitalization.

The doctors assumed the boy suffered from post-traumatic arthritis and prescribed non-steroidal anti-inflammatory drugs (NSAIDs) which were only minimally effective.

Six months later, a rheumatologist diagnosed Lyme disease, in part, due to a reported tick bite which occurred 3 months before the onset of the left knee arthritis. The patient did not have a erythema migrans (EM) rash.

Laboratory tests were consistent with the diagnosis of Lyme arthritis and doctors prescribed doxycycline.

On day 7 of antibiotic treatment, the boy developed a Herxheimer reaction. “On the 7th day of doxycycline treatment the patient’s condition deteriorated: a low-grade fever occurred, and severe arthralgias with intense hip, ankle and cervical spine pain and myalgias developed,” the authors explain.

The boy also had elevated CRP (C-reactive protein) and ESR (erythrocyte sedimentation rate). Steroids were prescribed.

There was no evidence of neurologic involvement and a spinal tap was normal. Nevertheless, doctors prescribed 4 weeks of intravenous ceftriaxone which led to a resolution of the joint swelling and less arthralgias.

Herxheimer reactions in Lyme disease patients

Jarisch-Herxheimer reactions have been described in the literature with a combination of symptoms occurring including fever, severe polyarthralgias, and myalgias, according to the authors.

Other Jarisch-Herxheimer reactions have also been described. The list includes “chills, high temperature, hypotension, nonpruritic, nonpalpable rash, tachycardia, nausea, headache, strengthening of existing or occurrence of new symptoms of the underlying disease,” the authors write.

Some studies have found that Herxheimer reactions were milder in patients with Lyme disease when compared to other diseases, without organ dysfunction or need for hospitalization, Nykytyuk  writes.

However, another case report by Haney et al., describes a more severe Herxheimer reaction in response to doxycycline in a patient with chronic Lyme disease. The patient developed “a low-grade fever, sore throat, sinus congestion, watery diarrhea, headache, stabbing pain in the upper back muscles, increased fasciculations and fatigue.” [2]

Physician education needed

The exact cause of Jarisch-Herxheimer reactions is still unknown.

“At first, the role of an endotoxin in the development of JHR was suggested, but later experimental studies showed that spirochetes do not have biologically active endotoxins,” the authors explain.

Nykytyuk and colleagues emphasize the importance in educating physicians about the Herxheimer reaction, as there appears to be a “low awareness.” For example, “JHR is often mistaken for an allergic reaction.”

Editor’s note: It is not uncommon for Lyme disease patients to have flare-ups with or without antibiotics. Some patients refer to these reactions as “Herxing,” in the absence of a more descriptive word. The mechanisms of these reactions are uncertain.  I typically avoid prescribing steroids to manage these reactions, as I do not want to suppress a patient’s immune system.

References:
  1. Nykytyuk S, Boyarchuk O, Klymnyuk S, Levenets S. The Jarisch-Herxheimer reaction associated with doxycycline in a patient with Lyme arthritis. Reumatologia. 2020;58(5):335-338. doi:10.5114/reum.2020.99143
  2. Haney C, Nahata MC. Unique expression of chronic Lyme disease and Jarisch-Herxheimer reaction to doxycycline therapy in a young adult. BMJ Case Rep 2016; 2016: bcr2013009433,
    DOI: 10.1136/bcr-2013-009433.

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For more:  

Category:

Detoxing, Lyme, research

New Study Identifies Bird Species That Could Spread Ticks & Lyme Disease

https://phys.org/news/2021-01-bird-species-lyme-disease.html

New study identifies bird species that could spread ticks and Lyme disease

by Cary Institute of Ecosystem Studies

New study identifies bird species that could spread ticks and Lyme disease

Birds play an underrecognized role in spreading tickborne disease due to their capacity for long-distance travel and tendency to split their time in different parts of the world—patterns that are shifting due to climate change. Knowing which bird species are able to infect ticks with pathogens can help scientists predict where tickborne diseases might emerge and pose a health risk to people.

A new study published in the journal Global Ecology and Biogeography used machine learning to identify bird species with the potential to transmit the Lyme disease bacterium (Borrelia burgdorferi) to feeding ticks. The team developed a model that identified birds known to spread Lyme disease with 80% accuracy and flagged 21 new species that should be prioritized for surveillance.

Lead author Daniel Becker, a Postdoctoral Fellow at Indiana University, says, “We know birds can infect ticks with the Lyme bacterium; however, until now, no one has systematically studied the ecological and evolutionary drivers that influence which bird species are most likely to host and spread Borrelia burgdorferi on a global scale. We set out to fill this gap by identifying traits of bird species that are most likely to pass Lyme to feeding ticks.”

Senior author Barbara Han, a disease ecologist at Cary Institute of Ecosystem Studies, says, “To predict and monitor species that could spread tickborne diseases to people, we first need to know which traits make certain animals good pathogen hosts. Here, we used machine learning to assess bird species traits, paired with Lyme infection data from ticks found on birds, to predict bird species that have the potential to spread Lyme.”

In this study, the team searched published literature to locate studies reporting Lyme infection of ticks found feeding on birds. The global search yielded 102 studies, including data from ticks found on 183 bird species; of these, 91 carried ticks that tested positive for Borrelia burgdorferi. These bird species are considered ‘competent’ reservoir species because they are known to infect feeding ticks with Borrelia burgdorferi. Species flagged have a broad range, reaching across the Americas, Africa, Asia, and Oceania.

Next, machine learning was used to compare traits of competent bird species with 4691 other bird species. Data included information on life history features like diet composition, foraging location, body size, lifespan, reproductive rate, and fledgling age, as well as geographical information like migration distance, global dispersal, and maximum elevation. They also looked at baseline corticosterone—the stress hormone in birds—which can influence susceptibility to infection.

New study identifies bird species that could spread ticks and Lyme disease

The model identified birds that were known to spread Lyme to ticks with 80% accuracy, and revealed 21 that should be prioritized for surveillance based on sharing traits with known competent species. High-risk species tend to have low baseline corticosterone, breed and winter at high latitudes and low elevations, are broadly distributed, and occur on either extreme of the pace-of-life continuum (species that breed early and die young, or breed late and are longer lived).

Species from the genus Turdus, commonly known as true thrushes, were found to have a significantly greater likelihood of competence compared to other taxa. This finding suggests that thrushes might be the riskiest bird species for Lyme transmission. Passerines, or perching birds, also tended to have higher competence, as did birds that primarily eat seeds and those that forage on the ground—a behavior that would put them in reach of questing ticks.

Identifying Lyme-competent bird species could have direct implications for our health. Tickborne diseases, especially Lyme disease, can be difficult to diagnose. Knowing where ticks and the diseases they carry are spreading can help medical practitioners prepare for diagnosis and treatment, improving health outcomes for patients.

Due to climate change, the breeding ranges of many birds are shifting north. As spread into higher latitudes, so do ticks and pathogens. Some have taken up full or part-time residence in cities and suburbs. Birds that can succeed in developed environments, especially those that are overwintering in these new places in close proximity to people, increase residents’ risk of contracting a tickborne disease.

Becker says, “Birds don’t spread Lyme directly to people, but they can carry infected ticks to new locations with no history of Lyme occurrence. A could drop off a bird and into a garden or yard, where it could later bite and infect a person. If local medical practitioners are unfamiliar with Lyme symptoms, proper diagnosis could be delayed. Identifying where ticks are spreading could improve medical response to Lyme and other tickborne diseases.”

Han concludes, “These findings remind us that pathogen competence varies tremendously, even among animals of the same family. Machine learning techniques allow us to analyze animal traits and help us predict risky species on a global scale—not only for Lyme, but for other tickborne and zoonotic diseases that involve multiple host . These predictions could provide crucial information to guide early interventions, prevent disease spillover, and protect our health.”

Explore further:  Model predicts where ticks, Lyme disease will appear next in Midwest states

More information: Daniel J. Becker et al, The macroecology and evolution of avian competence for Borrelia burgdorferi, (2020). DOI: 10.1101/2020.04.15.040352

Journal information: Global Ecology and Biogeography

Provided by Cary Institute of Ecosystem Studies

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For more:  https://madisonarealymesupportgroup.com/2018/11/07/ticks-on-the-move-due-to-migrating-birds-and-photoperiod-not-climate-change/

https://madisonarealymesupportgroup.com/2021/01/07/predicting-current-future-distribution-of-western-black-legged-tick-across-the-western-us/

https://madisonarealymesupportgroup.com/2021/01/26/mapping-lyme-cdc-reveals-distribution-of-lyme-disease-causing-bacteria-by-county/

https://madisonarealymesupportgroup.com/2021/01/14/cdc-updates-annual-estimate-of-those-diagnosed-treated-for-lyme-disease-from-300000-to-476000/

https://madisonarealymesupportgroup.com/2021/01/18/lyme-disease-much-more-common-than-previously-thought-study-shows/

Category:

Lyme, research, Ticks

Pediatric Lyme Disease Biobank, USA, 2015–2020: An Innovative Approach to Understanding Pediatric Lyme Disease

https://wwwnc.cdc.gov/eid/article/26/12/20-0920_article

Pediatric Lyme Disease Biobank, United States, 2015–2020

Lise E. NigrovicComments to Author , Desire N. Neville, Fran Balamuth, Michael N. Levas, Jonathan E. Bennett, Anupam B. Kharbanda, Amy D. Thompson, John A. Branda, Aris C. Garro, and the Pedi Lyme Net Working Group
Author affiliations: Boston Children’s Hospital, Boston, Massachussetts, USA (L.E. Nigrovic); Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA (D.N. Neville); Milwaukee Children’s Hospital, Milwaukee, Wisonsin, USA (F. Balamuth); Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA (M.N. Levas); Nemours/Alfred I. duPont Children’s Hospital, Wilmington, Delaware, USA (J.E. Bennett, A.D. Thompson); Children’s Minnesota, Minneapolis, Minnesota, USA (A.B. Kharbanda); Massachusetts General Hospital, Boston (J.A. Branda); Rhode Island Hospital, Providence, Rhode Island, USA (A.C. Garro)

Abstract

In 2015, we founded Pedi Lyme Net, a pediatric Lyme disease research network comprising 8 emergency departments in the United States. Of 2,497 children evaluated at 1 of these sites for Lyme disease, 515 (20.6%) were infected. This network is a unique resource for evaluating new approaches for diagnosing Lyme disease in children.

https://globallymealliance.org/an-innovative-approach-to-understanding-pediatric-lyme-disease/

An Innovative Approach to Understanding Pediatric Lyme Disease

by Mayla Hsu, Ph.D., Director of Research and Science, GLA

In the late 1970s, children presenting with arthritic symptoms were among the first cases of what is now known to be Lyme disease. Almost 50 years later, the incidence among kids remains high. Despite an estimated 400,000 new cases of Lyme disease annually in the U.S., with more than half being children, focused research to develop accurate diagnostics and improved treatments for them is lacking.

Global Lyme Alliance (GLA) funded the Pedi Lyme Net led by Lise Nigrovic, M.D., M.P.H., of the Division of Emergency Medicine at Boston Children’s Hospital.

To address this critical need, Global Lyme Alliance (GLA) funded the Pedi Lyme Net led by Lise Nigrovic, M.D., M.P.H., of the Division of Emergency Medicine at Boston Children’s Hospital. Dr. Nigrovic established Pedi Lyme Net, a network of seven children’s hospital emergency departments in five Lyme-endemic states. After obtaining informed parental consent, this network of pediatricians collects patient specimens from children suspected of having Lyme disease, or their clinical mimics, for testing and further research within Pedi Lyme Net.

Currently, the standard Lyme disease diagnostic blood test is problematic. Besides its inaccuracy in detecting early disease, the test also cannot distinguish new or persistent infections. Developing better diagnostic tests relies on having patient samples, alongside careful patient histories. An added feature of Pedi Lyme Net is that samples are also collected from control patients who visit the emergency room for non-Lyme related conditions, such as accidental fractures or lacerations. Altogether, the goal is to build a comprehensive data set for research.

Dr. Nigrovic recently published an article that describes Pedi Lyme Net’s Lyme disease screening results. Between June 2015 to January 2020, blood samples were obtained from 2,497 Lyme disease symptomatic patients and 377 asymptomatic control patients. All were analyzed with the C6 Lyme disease enzyme immunoassay, and those that were positive or equivocal were further tested with Western immunoblot, the standard Lyme disease test.

Among the 515 patients who tested positive for Lyme disease, the median age was 8, and 67% were boys, which correlates with national Lyme disease incidence statistics. The most common symptoms of those diagnosed with Lyme disease were fever, headache, facial palsy, and arthritis. These symptoms were used to classify Lyme patients into early, early disseminated, and late stage disease.

Among the Lyme-positive patients:

  • 8.9% had erythema migrans (EM) skin rashes alone
  • 89.5% had positive blood test results
  • 1.6% had both

These results show that the classic EM rash was only present in a minority of Lyme disease patients, and indicates that blood test results identify many more patients than skin rash alone. It also shows that many patients who are positive by blood test lack the skin rash.

Interestingly, only 15.6% of Lyme disease patients and their parents recalled a tick bite in the past year.

This is further evidence that tick bites are often missed, and reinforces that tick bite prevention is an important first step to reduce infections. A more in-depth study led by Dr. Nigrovic addressing this question shows the unreliability of tick bite history at predicting Lyme disease in children.

Pedi Lyme Net is a unique resource for advancing Lyme disease research. Besides being exclusively composed of pediatric samples, it also includes control pediatric samples, which are more appropriate as comparators than adults. Children’s bodies and physiology are not merely small versions of those of adults. Also, because the Pedi Lyme Net enrolls patients from emergency rooms, the samples are from symptomatic individuals, whose specific clinical presentations may be important information in understanding the basic science of disease. Finally, patient samples are from Lyme-endemic areas across the U.S., ensuring broad representation of pediatric Lyme patients.

Further studies of samples collected in the Pedi Lyme Net may involve understanding how different disease stages manifest in children, along with varied inflammatory biomarkers or immune correlates. One limitation of this study is the Western immunoblotting blood test may have given false negative results to some individuals who, early in disease, might not have developed the antibodies detected by this test. Follow-up calls to test later time points were done by Pedi Lyme Net researchers. And, since samples were banked, they can be tested with newly emerging diagnostic technologies in pursuit of designing tests with higher accuracy. Eventually, other tick-borne co-infections may also be studied in this population, since ticks frequently transmit not only Borrelia burgdorferi, the bacteria that cause Lyme disease, but other pathogens as well.

GLA is proud to support Pedi Lyme Net as it expands under the leadership of Dr. Nigrovic. This is an important research initiative that will lead to improved patient diagnostics and care. To date, Pedi Lyme Net data has led to over 10 peer-reviewed publications and scientific presentations.

Learn more about preventing Lyme in kids.
Blog: Kids and Lyme Disease: Cognitive Symptoms and School

Category:

Lyme, research, Testing, Ticks