Archive for July, 2014

July 24, 2014

Are Humans The Only Ones Who Get Lyme Disease?

Mosquito Squad of West Montgomery wants to keep you informed about Lyme Disease

Mosquito Squad of West Montgomery wants to keep you informed about Lyme Disease!

You may know that ticks get the Lyme bacteria, Borrelia Burgdorferi, from the white-footed mouse and then pass it on to us.  However, do the mice themselves get Lyme Disease?  Do they get sick?  What about all the other animals that ticks bite, like chipmunks, squirrels, raccoons, foxes, coyotes, birds and the like? The list of animals that ticks bite is a long one.  In order to make sense of the research, we need to break down this list.  It is easier to understand how Lyme Disease exists in wildlife by talking about small, medium and large animals, and birds.  The size of the animal seems to make more of a difference than the specie when discussing how Lyme Disease affects wildlife.

All size deer ticks can transmit disease.

All size deer ticks can transmit disease.

How is Lyme Disease transmitted? Before discussing how Lyme is transmitted, we need to define two terms.  The first is the term, host.  A host is, as you would expect, someone who serves someone something.  In the tick’s case, the host is the animal or bird who serves them their blood meal after the tick bites them.  A tick needs a blood meal in each of the three stages of its life cycle, larvae, nymph and adult in order to grow and move onto the next stage. The second term we need to define is reservoir.  Since ticks aren’t born with Lyme Disease, they need to get the bacteria from somewhere.  The term reservoir refers to where the bacteria are present.  Many animals can be reservoirs for the Lyme bacteria, Borrelia Burgdorferi.  Some reservoirs have an abundance of bacteria in their blood.  In other animal reservoirs, there may be very few Borrelia Burgdorferi bacteria.  An animal with a large number of bacteria in their blood are referred to as a competent reservoir.  This means they have enough bacteria to infect any ticks that bite them.  Other animal reservoirs can be incompetent reservoirs, meaning they have so few bacteria present they will not infect the tick when it bites them.

Small animals White-footed mice, chipmunks, rats, squirrels, moles, voles and certain species of birds are competent reservoirs.  These animals are often infected with Lyme Disease, as well as Anaplasmosis and Babesiosis.  These small animals are the ones most responsible for transmitting Lyme Disease to larvae and nymph ticks.  Since larvae and nymph ticks are often in the dens and burrows of these animals, they are often the young tick’s first blood meal.  The small ticks in this life stage do not need a lot of blood for their first meal.  Adult ticks need a larger animal for their larger blood meal. Although studies show these small animals are often infected with Lyme bacteria, there has been little to no research into how the disease affects them.  Whether they get a rash or sick from the bacteria is unknown.  One study that looked into the mortality of white-footed mice and showed 93% of them succumbed to predators, primarily weasels.  Only one mouse death in the study was attributable to Borrelia Burgdorferi bacteria.  From this study, we can hypothesize that most or all of these small animals can succumb to the infection, but it is not common. Is the lifecycle of the white-footed mouse so short or predation so high, that Lyme Disease doesn’t have a chance to take more of them?  We simply don’t know. Many studies have shown that birds are often infected with Lyme Disease and are responsible for its geographical spread.  One NIH study found, “ticks have detrimental effects on their avian hosts even under natural infestation conditions…and may also present symptoms of infection, though these may be subtle.”  Birds do seem to be affected physically by the Lyme bacteria; however, it is not acute or obvious.  Lizards may also become infected with Lyme Disease but are incompetent reservoirs.

Medium size animals Raccoons, groundhogs, rabbits, beavers, opossums, foxes, bobcats and coyotes rarely serve as reservoirs for Lyme Disease.  Scientists also do not find many ticks on them when sampled.  That doesn’t mean they don’t transmit other diseases.  Rabbits transmit tularemia, rarely Lyme Disease.  Beavers, like rabbits, transmit tularemia but are not identified with helping to transmit Lyme Disease.  Groundhogs transmit bronchopneumonia and hepatitis B primarily.  Squirrels transmit tick fever and their fleas can transmit plague.  Coyotes are incompetent reservoirs of Lyme Disease.  Foxes are also incompetent reservoirs of Lyme Disease. Foxes provide a benefit when it comes to Lyme Disease because they are predators of white-footed mice reducing their numbers. Even when the Lyme bacteria are found in these medium size animals, the bacteria present is minimal, making these animals incompetent reservoirs.  No research has been done on how or why the Borrelia Burgdorferi bacteria present in them is so low.  Whether some of these animals have less exposure to ticks carrying Lyme, or whether their immune system is prepared to prevent a significant infection, is not known.  Some scientists and studies have hypothesized that these animals may have a “primitive immune system” but no scientific definition exists for that term.  No studies exist to confirm or deny it.

https://mosquitosquadmaryland.files.wordpress.com/2014/07/egg-mass-produced-by-lone-star-tick.jpg

Egg mass produced by tick.

Large size animals The only wild large size animal in the tick lifecycle is the deer family. White tail Deer as well as other members of the deer family, including elk, moose and caribou are the blood meal host often chosen by adult ticks.  First, several thousand ticks can attach to deer because of their size.  This number of ticks makes it easy for males to locates the female ticks as ticks use deer to find a mate much like a local “pick-up” joint.  A female tick will use a deer to consume a large blood meal, in order to lay a clutch of 2,000 to 18,000 eggs.  Elk and moose carry dog ticks in the West, which are often infected with Ehrlichiosis and can be transmitted to humans.  With the introduction of elk and moose in the Eastern US, no one knows the effect they may have in Lyme Disease and Ehrlichiosis transmission. All deer are incompetent reservoirs with low levels of Lyme bacteria in their blood, despite the number of ticks that bite them.  Once again, scientists attribute the deer’s immunity to a primitive immune system or an ability to flush the bacteria from their blood. Based on numerous research papers, it is clear that the animals most responsible for transmitting Lyme Disease are small ones, especially white-footed mice, voles and other rodents.  Research studies show that voles become important in the transmission of Lyme bacteria mostly in areas where few white-footed mice exist.  Medium size and larger animals and birds spread the disease further geographically that any of the smaller animals because of their territorial ranges and their effectiveness in giving infected ticks a ride to new locations.

Susan Levi, Owner Mosquito Squad of West Montgomery.

Susan Levi, Owner Mosquito Squad of West Montgomery.

Tracing the epidemiology of Lyme Disease is complex, as you can see.  With so many vectors, hosts and reservoirs responsible for the disease, researchers are a long way off from knowing how the disease continues to spread. Rather than wait for science to provide a solution, there are effective solutions now such as barrier sprays for your yard. Contact Mosquito Squad of West Montgomery now to discuss our tick barrier spray and tick tube program that will protect your yard all season long.

Learn more about protecting yourself and your family from the risks of tick-borne illnesses such as Lyme Disease in your backyard! Sign up today • (301) 444-5566 • email:westmontco@mosquitosquad.com

 

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July 20, 2014

Would you know if your dog has Lyme Disease?

Rockville MD Canine Lyme Disease prevention

You may not know “man’s best friend” can also contract Lyme Disease, but they can!

The answer is not so clear.  You may not have realized your pet could get Lyme Disease like humans, until your were asked the question.  Dogs, cats and horses can and do get Lyme Disease from ticks, as well as 3 other serious infections ticks carry.  Your dog’s Lyme Disease symptoms are different from ones you may have; or, they may not appear at all.  If symptoms do appear, they may seem to leave on their own and reappear later.  The lack of symptoms and seemingly temporary nature of Lyme Disease symptoms in your dog can make a correct diagnosis difficult.

Of course, dogs are perfect targets for ticks.  When ticks are “questing” or looking to hitch a ride on an animal to obtain their blood meal, they usually hold onto limbs, grasses and other objects about knee-high in height.  They are looking for coyotes, raccoons, possums and yes, your best friend, your dog.  All of these animals, including your canine family member, enjoy exploring interesting and new places outdoors like brush piles, rock piles, thick grass and the like are also perfect places for ticks to live and look for a meal.

In a story for mspca.org, Erika de Papp, DVM, DACVIM reported that it is common for 50-75% of dogs in New England test positive for Lyme Disease.  Of course, Lyme Disease is endemic in New England, as it is in Maryland.  For dogs that test positive to Lyme Disease, only 5-10% may show clinical symptoms of the disease.  If your dog doesn’t show any clinical symptoms, some veterinarians argue against treatment in healthy dogs.

deer tick control and prevention in Rockville MD

Lyme Disease is transmitted through the bite of a deer tick.

The most serious consequence of untreated Lyme Disease can be kidney disease in your dog.  If your dog tests positive for Lyme Disease based on blood tests but is not treated, discuss the benefit of kidney function tests with your veterinarian.  Until recently, veterinarians could only test if your pet’s blood had antibodies present indicating a Lyme infection had occurred.  These tests couldn’t determine if the infection was recent or one your dog had for some time.  A new test to diagnose Lyme Disease in dogs has now been developed to determine if the infection in your dog is recent, which means a better prognosis for treatment.  Of course, your veterinarian will have the most current information on tests used to diagnose an infection and confirm the need for treatment.

The clinical symptoms of Lyme Disease in dogs are fever, decreased appetite, tiredness, swollen and painful joints that may be painful to examination and lameness or limping that may seem to shift between legs.  The appearance of these symptoms between the time of the bite and when they occur may be 2 to 5 months apart.  Symptoms may also appear to clear up, only to return later.  It is important to keep up with any symptoms you observe in your dog and to document when they occur.

Canine Lyme Disease in Rockville MD

Keeping your furry friend happy and healthy is up to you!

With the prevalence of Lyme Disease in some of our most precious canine family members, as well as the difficulty in diagnosing a disease often without symptoms, the prevention of tick bites should be your first priority.  The use of a parasite preventative and regular tick checks of your dog whenever they return indoors are important in Lyme Disease prevention.  In order to eliminate your dog’s exposure to ticks, remove any brush piles and leaf litter on your property and keep grass cut low.  Hard ticks such as the black-legged tick, or deer tick, dry up when exposed to the sun or heat for long periods.  They need shade and moisture, so eliminating their hideouts and keeping your lawn trimmed low will help protect your pets as well as your family from ticks.

Finally, choose our effective and proven barrier spray , as well as out tick tube treatments.  Reduce the population of ticks in your yard and you will have greatly reduced the risks of Lyme Disease for you and your dog!  Don’t forget: Barrier sprays, like the ones used by Mosquito Squad of West Montgomery, eliminate both ticks and mosquitoes.  We’ve discussed here the risk of Lyme Disease to your canine family members.  For your dogs, the mosquito bites bring on heartworm.  Our effective barrier spray will eliminate both pests around your home.

mosquito-squad-family Rockville MD

Contact Mosquito Squad today to learn more about reducing the risk of tick and mosquito-borne illness this season!

To answer more questions about protecting yourself and your family, ( including the four-legged kind) against mosquito and tick-borne diseases, please contact Mosquito Squad of West Montgomery and sign up today • (301) 444-5566 • email:westmontco@mosquitosquad.com

July 7, 2014

Can Lyme Disease Be Transmitted Sexually?

Male and female symbolYou may have heard some discussion lately on the sexual transmission of Lyme Disease.  If you haven’t heard it, you will.  Combine sex with the word disease and you immediately have two subjects in which nearly 100% of the people on earth will be interested.  If advertisers love any news, it is news about subjects that touch people personally.  Sex and disease both fit that criterion.

So what’s the latest information on this subject?  Much of the news is old news.  At the 14th International Scientific Conference on Lyme Disease in April 2001, Dr. Gregory Back presented a paper on “Recovery of Lyme Spirochetes by PCR in Semen Samples of Previously Diagnosed Lyme Disease Patients”.  The first thing to understand about this paper is that 40% of the 132 partners studied (66 couples) were both found to be infected with Lyme Disease.  Lyme Disease, Science and Society looked at this research and after examining the evidence of this early study stated:

There are unanswered questions about this study based on the abstract: We don’t know what kind of microscopic confirmation was conducted and why it was mostly conducted on semen.  We don’t know if patients had other possible routes of exposure to spirochetes.  We don’t know if the DNA sequences recovered matched between sexual partners.  We don’t know whether any of the patients who were sampled had recently taken antibiotics and if the spirochetal DNA that was detected was the result of their bodies trying to purge a massive die-off of spirochetes.  What kind of treatment patients in the study had received so far is an unknown.

Deer tick awaiting a host in Rockville MDAs you can see, the individuals in the study were not tested prior to finding a Lyme infection, in order to establish when the infection occurred.  There was also no evidence of actual transmission or research into the exact origin of the partner’s infection, only evidence that both partners had Lyme Disease.  Since partners live in the same environment, it’s very possible that one partner didn’t remember being bitten by a tick.  Nymph ticks are the size of a poppy-seed and difficult to detect.  Due to their small size, they are often not found by their human host unless seen fully engorged with blood.  Simply stated, it’s a leap to identify two related patients and make a leap that one gave the other any disease.  For example, if a husband has the flu, his wife may think he gave it to her.  In fact, she may have gotten it from someone at work.  Infectious diseases in the real world don’t always neatly move in the direction we expect.

Other studies claim that the spirochetes of syphilis and those of Lyme Disease are similar.  While it’s true they are similar, they do not share the same environmental preferences.  Lyme spirochetes don’t survive very long on the surface of the skin.  However, syphilis spirochetes do very well in moist superficial skin lesions.

If detected during pregnancy, Lyme Disease can be easily treated in the mother with antibiotics that do not harm the fetus.  The CDC says, “Untreated Lyme disease during pregnancy may lead to infection of the placenta and possible stillbirth.”  Lymediseaseassociation.org says, “The bacteria can also be passed through the placenta of a pregnant woman to the fetus—congenital transmission.”  Since a Lyme infection occurs through the blood, it makes sense a fetus can become infected.

When considering breast milk in mothers, the DNA of Lyme Disease has been found.  This does not mean it has been proven that a newborn can get Lyme Disease through breast milk, only that evidence of the disease is present in the milk.  There have not been any cases linking breast milk in the transmission of Lyme Disease.

Researchers know that the Lyme bacteria can survive blood bank storage conditions.  Once again, there have been no suspected cases of Lyme transmission through blood transfusions.  However, animal studies do show that Lyme bacteria can be transmitted through blood transfusions in mice.

EngorgedFemaleDeerTicks

The CDC does not consider the transmission of Lyme Disease through sexual intimacy very likely.  As mentioned earlier, there is anecdotal evidence of possible sexual transmission but much more research needs to be done.  There are already enough sexually transmitted diseases for everyone to be concerned about transmitting to their sexual partners, without knowing if Lyme Disease is one of them.  Taking precautions regarding any infection someone may have, on behalf of sexual partners, should be common sense behavior.

tick_habitatScientists know that it generally takes 24-36 hours before a tick can transmit Lyme Disease through its bite.  Therefore, even with a tick carrying Lyme Disease, it takes some time for the infection to be transmitted.  Once established a Lyme infection can be long-lasting.  Even after successful treatment and test results showing no Lyme Disease is present, Lyme spirochetes, B. burgdorferi, can be present in small numbers in patients for years.  Until further research is done, it only seems prudent to be safe until a physician confirms a Lyme infection no longer exists.

Contact Mosquito Squad of West Montgomery  to learn more about protecting yourself and your family from the risks of tick-borne illnesses such as Lyme Disease in your backyard! Sign up today • (301) 444-5566 • email:westmontco@mosquitosquad.com