Lyme

What Is Lyme Disease? New Findings Deepen the Mystery

Posted on Apr 9, 2014

What Is Lyme Disease? New Findings Deepen the Mystery

Reprinted from NATIONAL GEOGRAPHIC Rampant disagreement over what constitutes Lyme disease—in particular, who may have contracted it and how, and how long it lasts—has spawned the larger question of how best to treat it. A new study pointing to the possibility of sexual transmission of the pathogen adds fuel to the fire. Amid the uncertainty, a patient-led lobby (the counterculture, as someone has called it) that includes doctors as well as Lyme sufferers advocates a broader definition of the disease, both for treatment and insurance purposes. But the medical establishment asserts that too liberal a definition—and what are seen as renegade practitioners—has led to irresponsible and potentially dangerous treatment of unrelated maladies misidentified as Lyme. It’s also unknown how many people have died because of Lyme. A 2011 study found that of the 114 deaths reported over a five-year period listing Lyme as a partial or direct cause, only one was consistent with clinical manifestations described by the International Classification of Diseases. In December 2013, the Centers for Disease Control and Prevention (CDC) confirmed that Lyme carditis—a condition in which the Lyme bacterium infects the heart—caused three deaths over the past two years. Between 1985 and 2008, only four other fatal cases were confirmed. While the course of the illness varies greatly from person to person, initial manifestations can include a unique skin lesion known as erythema chronicum migrans, headaches, musculoskeletal pain, coughing, sore throat, conjunctivitis, and minor neurological impairment. If the diagnosis is confirmed early enough, Lyme is treated almost exclusively with short-term antibiotics, often penicillin, which are almost 100 percent effective. But if Lyme goes untreated, symptoms can progress. (Watch related video: “The Deer Tick”) In Lyme’s second stage, typically between one and several months after the initial infection, neurological abnormalities can arise, such as meningitis, encephalitis, and cranial neuritis, which can manifest as facial palsy. Some patients develop cardiac problems. In the third stage, which can take several months to years to show up, many patients develop chronic arthritis as well as an increase in neurological and cardiac symptoms, the severity of which can ebb and flow. Voices in the counterculture argue that Lyme’s symptoms are more intense and longer lasting than the medical establishment acknowledges. They say that symptoms of chronic Lyme disease are responsible for related deaths, including suicides from depression about the disease or from the trauma of persistent debilitating symptoms such as arthritis, heart problems, and cognitive impairment. New Developments   And now, further complicating the picture, a study published this January contends that Lyme disease may be sexually transmitted. It shows that the Lyme pathogen, Borrelia burgdorferi (Bb), has been found in both male and female sexual secretions, raising the question of whether people are at risk through intimate contact. Bb is one of only six known spirochete bacteria, named for their coiled spiral shape. (One of the six is the bacterium responsible for syphilis.) PHOTOGRAPH BY SCIENCE PICTURE CO., CORBIS Borrelia burgdorferi is the bacterial agent of Lyme disease. The primary vector for Bb is the deer tick—Ixodes scapularis—although other kinds of ticks have been known to transmit it, and other insects, including some mosquitoes, carry the pathogen. A study of Bb last year revealed that it’s the first known organism that doesn’t need iron to survive. This allows it to evade an iron-inhibiting hormone called hepcidin, produced by the liver, which can starve intrusive bacteria. Instead, Bb thrives on manganese, which it uses to make essential enzymes for survival—something researchers who made the discovery last year believe could play a role in ultimately combating the pathogen. Origins: Did Ötzi...

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Lizards Slow Lyme Disease in Western U.S.

Posted on Nov 11, 2013

Lizards Slow Lyme Disease in Western U.S.

It may sound like witchcraft, but Berkeley scientists have found that ticks who feast on the blood of the common western fence lizard are purged of any Lyme disease bacteria hiding in their gut. The newly published findings may explain why there is less tick-borne Lyme disease in California than in the eastern United States, where the debilitating illness was first discovered and given its name. Researchers suspect that a yet- to-be-identified protein in the lizard’s blood destroys the microbes that would otherwise flourish in the tick’s belly and can be later transmitted to human victims. “We’ve speculated on this for years, and now we have fairly good evidence that this is the case,” said Robert Lane, a University of California at Berkeley insect biologist who has been studying ticks and Lyme disease for more than a decade. Lane and his colleague Gary Quistad conducted a series of laboratory experiments using young Lyme disease-infected ticks and fence lizards. In the nymphal stage during which they feed on the blood of lizards, the ticks are only about the size of a poppy seed. But it is common to find 30 to 40 at one time sharing the blood of a single fence lizard. Although infected adult female ticks pose a serious threat of transmitting Lyme disease to humans, the smaller nymphal ticks are the most dangerous because they are harder to find and are still capable of transmitting the disease. Lane had determined eight years ago that the lizards appeared to be immune to Lyme disease despite infestation with tick nymphs. His latest research, published recently in the Journal of Parasitology, suggest why this happens. The experiments first ruled out the possibility that antibodies produced by the lizard’s immune system were able to neutralize the Lyme disease bacteria. Test tube experiments found that Lyme disease bacteria bathed in lizard’s blood died within one hour, while control samples grown in mouse blood lasted three days. In another experiment, the researchers heated lizard blood to the boiling point, and found that it no longer killed the bacteria in a test tube. The sum of these tests points to what Lane calls a “spirochete-killing factor” that is probably a large protein. “It’s an extremely important paper,” said Vicky Kramer, chief of the vector-borne disease section of the California Department of Health Services. Researchers are now trying to determine the precise nature of the Lyme disease-killing protein, and perhaps find out if it can be used to create a treatment for the disease. Lane said he has not yet discussed his findings with biotechnology companies. California health officials long have been pleasantly puzzled by the fact that Lyme disease is a relative rarity in the state, despite an abundance of ticks. Lane points out that in the eastern regions with higher Lyme disease rates, “they don’t have fence lizards there.” Berkeley’s Tilden Park served as the field laboratory for Lane, where he previously also uncovered a curious quirk about Lyme disease and the black-legged ticks that carry it there: the infection rates for young ticks, while low, was three to four times higher than the rate in adult ticks. The latest findings again suggest why: When young nymphal ticks feed on the fence lizards, the mysterious protein not only protects the lizard from infection — it actually leaches into the tick’s gut and kills the bacteria there. READ...

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New Tick-Borne Illness Could Be Worse Than Lyme Disease

Posted on Oct 3, 2013

New Tick-Borne Illness Could Be Worse Than Lyme Disease

Doctors May Not Even Know To Look For Borrelia Miyamotoi Infection A new disease spread by deer ticks has already infected 100,000 New Yorkers since the state first started keeping track. As CBS 2’s Dr. Max Gomez reported, the new deer tick-borne illness resembles Lyme disease, but is a different malady altogether – and it could be even worse. The common deer tick is capable of spreading dangerous germs into the human bloodstream with its bite. However, Lyme disease is one of many diseases that ticks carry. The latest disease is related to Lyme, and an infected person will suffer similar symptoms. “Patients with this illness will develop, perhaps, fever, headache, flu-like symptoms, muscle pains — so they’ll have typical Lyme-like flu symptoms in the spring, summer, early fall,” said Dr. Brian Fallon of Columbia University. “But most of them will not develop the typical rash that you see with Lyme disease.” Fallon, a renowned expert on Lyme disease at the New York Psychiatric Institute, said the importance of the new bacterium – called Borrelia miyamotoi — is that it might explain cases of what looked like chronic Lyme disease, but did not test positive for Lyme. “The problem is that the diagnosis is going to be missed, because doctors aren’t going to think about Borrelia miyamotoi because they don’t know about it. And number two, if they test for Lyme disease, it will test negative, and the rash won’t be there,” Fallon said. “So they are not going to treat with the antibiotics, so the patient will have an infection staying in their system longer than it should. While there is no test yet for the germ, the good news is that it appears the same antibiotic that kills Lyme disease also works – if it is given in the right doses and started early in the infection. Remember, it takes a tick bite to get Lyme disease or the new bug, and the tick usually has to feed on your blood for at least 24 hours. If you have been outdoors, have someone else do a full body check, Gomez advised. Ticks are small – only about the size of a sesame seed. READ...

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