Archive for the ‘research’ Category

1st Report of Deer Ticks Parasitizing a North American Porcupine in Canada

https://www.mdpi.com/2673-6772/1/2/6/htm

First Report of Ixodes scapularis Ticks Parasitizing a North American Porcupine in Canada

by John D. Scott
 
 
Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
Academic Editor: Theo De Waal
Parasitologia 2021, 1(2), 45-49; https://doi.org/10.3390/parasitologia1020006
Received: 16 February 2021 / Revised: 18 March 2021 / Accepted: 25 March 2021 / Published: 1 April 2021

Abstract

Adult females of the blacklegged tick, Ixodes scapularis (Acari: Ixodidae), were collected from a North American porcupine, Erethizon dorsatum, in eastern Ontario, Canada. This porcupine parasitism indicates that an established population of I. scapularis is present in the local vicinity. This tick species is known to parasitize more than 150 different vertebrate hosts, including the North American porcupine. The presence of I. scapularis ticks parasitizing a North American porcupine constitutes a new tick-host record in Canada.

1. Introduction

The North American porcupine, Erethizon dorsatum (Rodentia: Erethizontidae), also known as the Canadian porcupine, is a herbivore rodent. This meso-mammal is one of the largest members in the rodent family, and has wide distribution across continental North America. This woodland denizen is native to coniferous and mixed forests across southern Canada, and its distribution extends southward into northeastern, north-central, and western United States as far south as the northern fringe of Mexico. Ecologically, free-ranging porcupines have a home range of up to 28 ha. This arboreal herbivore is covered with a coat of quills that arm it from predators. Once a porcupine is threatened, it will hide its face, swat its tail at its assailant, and thrust an arsenal of quills in multiple directions to strike its attacker. The sharp, needle-like quills are painful, and prudent attackers retreat. In the spring and summer, porcupines feed on berries, seeds, grasses, leaves, roots, and stems. In the winter, North American porcupines feed on the inner bark of trees. As these herbivore rodents forage for food, they make direct contact with low-lying vegetation where ticks are questing.
Blacklegged ticks, Ixodes scapularis (Acari: Ixodidae), are indigenous across North America east of the Rocky Mountains [1]. Ixodidae, commonly referred to as hard ticks, are predominantly blood-feeding ectoparasites of mammals and birds although several species feed on reptiles [1]. Tiny ticks maintain a stealth presence in the natural environment, and covertly parasitize North American porcupines. These quill-laden rodents are primarily nocturnal, but will defend themselves at any time of day. In Wisconsin, wildlife rehabilitators collected I. scapularis adults from several North American porcupines [2].
 
The locality where the free-ranging porcupine was found is in the Great Lakes-St. Lawrence forest region which consists primarily of red pine, eastern white pine, eastern hemlock, yellow birch, sugar maple, and red oak [3]. In a tick-host study conducted across Ontario with veterinarians, wildlife rehabilitators, and the public, acarologists previously detected I. scapularis ticks on domestic dogs, cats, and humans in the same precambrian area (Canadian Shield) [4]. Although porcupines have feeding activities in trees, these spiny rodents will have direct contact with low-lying vegetation when they are feeding at ground level. If present, this is where I. scapularis ticks are questing. Depending on the time of year and their developmental life stage, I. scapularis ticks conduct host-seeking activities anytime through the day. Several blacklegged ticks collected within a single collection period (a single year) indicate that a reproducing population of I. scapularisis present [5,6].

2. Results

The North American porcupine was found on the side of the road north of Westport, Ontario on County Road 10 (44.687° N, 76.385° W), which is situated within the Canadian Shield (Figure 1). The injured porcupine was taken to Sandy Pines Wildlife Centre, Napanee, Ontario, and a wildlife rehabilitator examined it. Since the head had visible trauma, it is believed that the porcupine was struck by a passing vehicle. Based on a x-ray, veterinary technicians also found a diaphramatic hernia. Due to the severity of trauma, the North American porcupine was promptly euthanized upon arrival, and five partially engorged I. scapularisfemales were collected.

3. Discussion

The collection of five engorged I. scapularis females feeding on a North American porcupine is a novel discovery in Canada (Figure 2). Based on a literature search [2,7,8,9] and the Canadian National Collection, the author affirms that this mammalian parasitism is the first documentation of I. scapularis parasitizing a North American porcupine in Canada. (See link for full article)

New Lyme Disease Test Distinguishes Between Early and Late-Stage Disease

ihttps://medicalxpress.com/news/2021-04-lyme-disease-distinguishes-early-late-stage

New Lyme disease test distinguishes between early and late-stage disease

April 7, 2021

Lyme disease

For those who live in an area blighted by ticks, the threat of Lyme disease can cast a shadow over the joy of spring and summer. These blood-sucking arachnids can transmit bacteria into the bloodstream of their unsuspecting host, causing the disease. Early treatment is essential, but current tests are not usually sensitive enough to detect the disease in early-stage patients. A recent study in open-access journal Frontiers in Microbiology reveals a new test for Lyme disease, which is the first to reliably distinguish between early- and late-stage patients. The test detects a genetic sequence left by a virus that resides in Lyme-causing bacteria, and can detect just one bacterial cell in a small blood sample.

As the most common tick-borne infection, Lyme affects nearly 500,000 people in the U.S. every year. Symptoms include fever, fatigue, joint pain, and a distinctive ‘bullseye’ rash, but if left untreated, the disease can cause paralysis and even death. As such, is important, but difficult.

“Early diagnosis of Lyme disease is absolutely vital in reducing suffering, because early Lyme can be treated, but late Lyme is very difficult to treat,” explained Dr. Jinyu Shan of the University of Leicester, lead author on the study. “Current tests cannot typically detect the low numbers of bacteria in early-stage patient blood samples. Our goal was to design a highly sensitive to help doctors to identify Lyme disease as early as possible.” (See link for article)

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Study here: https://madisonarealymesupportgroup.com/2021/03/31/targeting-multicopy-prophage-genes-for-the-increased-detection-of-borrelia-burgdorferi-sensu-lato-the-causative-agents-of-lyme-disease-in-blood/

Evidently the test is unique in that it is based on prophages that have a genetic sequence inserted into the bacteria by a virus which can escape the bacteria, and is more likely to be picked up in the blood due to having multiple copies within cells.

They found the test is sensitive and can detect one bacterial cell in .3 mL of blood.  Infected patients have between 1-100 bacterial cells per mL of blood.

The test is the first to distinguish between healthy, early-stage, and late-stage samples.


I must admit that the debacle with PCR testing for COVID has made me extremely skeptical and wary.  I hope that this isn’t too good to be true.  Time will tell.

Tick-borne Diseases & Coinfection: Current Considerations

https://www.sciencedirect.com/science/article/abs/pii/S1877959X20304775

Tick-borne diseases and co-infection: Current considerations

Abstract

Over recent years, a multitude of pathogens have been reported to be tick-borne. Given this, it is unsurprising that these might co-exist within the same tick, however our understanding of the interactions of these agents both within the tick and vertebrate host remains poorly defined. Despite the rich diversity of ticks, relatively few regularly feed on humans, 12 belonging to argasid and 20 ixodid species, and literature on co-infection is only available for a few of these species. The interplay of various pathogen combinations upon the vertebrate host and tick vector represents a current knowledge gap. The impact of co-infection in humans further extends into diagnostic challenges arising when multiple pathogens are encountered and we have little current data upon which to make therapeutic recommendations for those with multiple infections. Despite these short-comings, there is now increasing recognition of co-infections and current research efforts are providing valuable insights into dynamics of pathogen interactions whether they facilitate or antagonise each other. Much of this existing data is focussed upon simultaneous infection, however the consequences of sequential infection also need to be addressed. To this end, it is timely to review current understanding and highlight those areas still to address.

Lyme Disease Can Impact Your Vision’s “Contrast Sensitivity”

https://www.lymedisease.org/lyme-vision-contrast-sensitivity/

By Lonnie Marcum

March 30, 2021

LYME SCI: Lyme disease can impact your vision’s “contrast sensitivity”

Lyme Causes “False Brain Tumor” in Child

https://danielcameronmd.com/lyme-disease-false-brain-tumor-child/  Podcast here

LYME DISEASE CAUSES “FALSE BRAIN TUMOR” IN YOUNG CHILD

brain-lyme-disease

Welcome to another Inside Lyme Podcast. I am your host Dr. Daniel Cameron. I find that the best way to get to know Lyme disease is through reviewing actual cases. In this episode, I’ll be discussing a case involving a 9-year-old boy with with a pseudotumor cerebri due to Lyme disease.

Ezequiel and colleagues first described this case in the British Medical Journal Case Reports in 2017.¹

Pseudotumor cerebri means “false brain tumor” because its symptoms are similar to those caused by brain tumors. It’s also known as idiopathic intracranial hypertension.

Symptoms mimic brain tumor 

The boy was admitted to the hospital with “daily pulsatile frontotemporal headache, pallor, photophobia and phonophobia, without night awakening, vomiting or visual changes,” the authors write. (Photophobia is sensitivity to light. Phonophobia is fear or aversion to sound.)

The doctors found papilloedema, which is swelling of the optic disc but no neck pain. A CT scan of the patient’s head was normal. He had an increased opening pressure in his spinal tap. In other words, the fluid removed from his spinal tap was under higher pressure.

Pseudotumor cerebri is a condition caused by elevated cerebrospinal fluid pressure in the brain.

The boy was diagnosed with a pseudotumor. Pseudotumor cerebri is a condition caused by elevated cerebrospinal fluid pressure in the brain. Symptoms can mimic a brain tumor, but in fact are due to intracranial pressure in the head.

He was prescribed acetazolamide while undergoing further evaluation. (Acetazolamide is a diuretic and carbonic anhydrase inhibitor medication that is used to reduce eye pressure.)

The boy was tested for a wide range of bacterial and viral infections, all of which were negative.

Treatment for neuroborreliosis 

He lived in Portugal and because he had visited the countryside prior to developing symptoms, he was tested for Lyme disease. A Western blot and spinal tap revealed he was positive.

The boy was diagnosed with Lyme disease and treated with a 21-day course of intravenous ceftriaxone. He recovered completely.

The authors point out, “CSF [cerebral spinal fluid] changes are not common, so in their presence, it is compulsory to investigate an infectious origin, as happened in this case, as the intracranial hypertension might be the only symptom of a central nervous system infection.”

Furthermore, “Borrelia infections should be actively investigated in children with central nervous system disease even in non-endemic areas.”

The following questions are addressed in this Podcast:

1. What is Pseudotumor cerebri and why is it referred to as ‘false brain tumor?’
2. What are the causes and how is it diagnosed?
3. How often does pseudotumor cerebri occur in Lyme disease?
4. Can it be the only manifestation of Lyme disease?
5. Can you discuss the boy’s initial treatment?
6. What are your thoughts on the treatment he received for Lyme disease?

    Thanks for listening to another Inside Lyme Podcast. You can read more about these cases in my show notes and on my website @DanielCameronMD.com. As always, it is your likes, comments, reviews, and shares that help spread the word about Lyme disease. Until next time on Inside Lyme.

Please remember that the advice given is general and not intended as specific advice as to any particular patient. If you require specific advice, then please seek that advice from an experienced professional.

Inside Lyme Podcast Series

This Inside Lyme case series will be discussed on my Facebook and made available on podcast and YouTube.  As always, it is your likes, comments, and shares that help spread the word about this series and our work. If you can, please leave a review on iTunes or wherever else you get your podcasts.