Life After Lyme Disease

Microscopic Image of a Tick

Bacteria are some of the oldest forms of life on earth, and all life is thought to have developed from these simple but highly effective organisms.  During Earth’s turbulent history bacteria and other basic life forms have survived many natural disasters from devastating global forest fires to volcanic eruptions, glacial ages and meteor strikes, of all which saw billions of other species become extinct, and one of the greatest mass extinctions in history during the Permian Period 248 million years ago saw so many animal species wiped out (including 90-95% of all marine life) that Earth very nearly returned to a similar state as the Precambrian eon 3–4 billion years ago, where the only life on earth were microorganisms.

Pre-Ice Age Europe

It is not surprising to learn then that researchers have now discovered that the bacterium responsible for Lyme disease (Borrelia burgdorferi) is incredibly old and could actually predate the Ice Age, and was also thought to have originated in the continent we now know as Europe, rather than North America.

Previously experts had believed that the Borrelia burgdorferi bacterium originated in North America, but new studies from researchers at the University of Bath, which combined findings from both the UK and USA, have revealed a fascinating evolutionary history to this bacterium that charts its emergence and spread all the way back to pre-Ice Age Europe.  This research was gathered by extracting samples from infected ticks and humans and studying the sequence of a number of ‘housekeeping genes’ (a code for proteins which are essential for basic cell functions and present under any conditions), which evolve very slowly over a long period of time.  Because these housekeeping genes are so fundamental to the survival of the cell they are passed down through history largely unchanged, and contain valuable information dating back to the origins of the cell, and from this scientists can track the evolutionary path of the bacterium.

Results from Studies

From the results of the study carried out by the University of Bath’s Department of Biology & Biochemistry, researchers found 33 different combinations of these housekeeping genes in just 64 samples, and from this they were able to construct a ‘family tree’ based on actual molecular information, which is the first time this technology has been applied to tick-borne disease.  This family tree revealed that the oldest molecular information charted the origins of the Borrelia burgdorferi bacterium back to pre-Ice Age Europe, but did also show that it has been present in North American for a very long time as well.  The research also suggested that the geographic territory of the tick species that carry the Borrelia burgdorferi bacterium spread in the 1970’s, which can explain the re-emergence of Lyme disease during this time, and this may have been linked to efforts to restore woodland in North America that created new sustainable habitats for insects such as ticks to breed and spread.

The importance of this research cannot be underestimated as by understanding more about how this bacterium has spread throughout history, experts can predict more accurately just how it will develop into the future, and find more effective ways in which to combat and contain it.

New studies published in the November 2009 issue of Cell Host & Microbe (a leading scientific journal published by Cell Press) have shown some possible ways forward for scientists who are working hard to develop an effective vaccine for Lyme disease, which is caused by the bacterium Borrelia burgdorferi and transmitted through tick bites.  Researchers at the Yale School of Medicine and the Howard Hughes Medical Institute have discovered evidence that suggests a vaccine could be developed from a protein in the tick’s salvia (the pathogen’s transmitting agent), which could confer immunity to those people living in areas affected by this disease.

Developing the Vaccine

The interaction between the Borrelia burgdorferi bacterium and ticks is highly complex, and lead author Erol Fikrig, M.D. of Yale University stated that the recent studies have shown that the bacterium actually uses a protein in the tick’s saliva to ‘facilitate infection of the mammalian host’.  This means that the bacteria effectively ‘wraps’ itself in a coating of these proteins (which it stimulates the tick into producing in excess quantities), which masks its presence from the host’s immune system and allows it to pass into the system unnoticed.  Researcher believe that this interaction between the protein in the tick’s salvia and the bacterium is absolutely key to the infection process, and by interfering with this process an effective protective vaccine could be developed against Lyme disease.

Previous vaccines have been developed against Lyme disease but these have subsequently been removed from the market following unsuccessful field trials, and as yet no other antigens have been released for testing in phase III clinical trials.  These previous vaccinations targeted just the outer surface proteins of the pathogen itself, but the new research suggests that by adopting a different strategy and targeting the transmitting agent (in this case the tick’s salvia) instead of the pathogen a much more effective form of defense could be developed, which could have far reaching effects in the fight against not just Lyme disease, but other harmful insect-borne pathogens that as yet we are unable to vaccinate against such as dengue fever, West Nile virus and even one of the most deadly killers in the world, malaria.

As yet the research on tick’s saliva is still only in the laboratory stages, but the initial studies on animals at the Howard Hughes Medical Institute have shown that mice test subjects responded well to a basic antiserum produced to interfere with the protein in the tick saliva identified as being essential to the Borrelia burgdorferi bacterium infection of the host, which significantly reduced the risks of the mice becoming infected with Lyme disease after being exposed to this tick-borne pathogen.

Hope for the Future

These results are encouraging for the future of vaccination against not just Lyme disease but other insect-borne diseases, and can certainly bring a measure of hope for all those living in areas affected by the Borrelia burgdorferi bacterium.  Ticks produce anesthetics in their salvia that stop the bite from stinging, so in many cases the host does not even realize they have been attacked by the insect, and Lyme disease is an insidious condition and can be difficult to diagnose in the early stages as symptoms are wide ranging and include rashes (that can go unnoticed), fever and chills, tiredness, weakness and joint pain, and if left untreated can result in serious conditions such as heart problems and chronic fatigue.

If you know anything about Lyme disease, it is that there are conflicting opinions on how to treat the problem. In fact, this has been a sticking point for many years and it does not seem that things are going to calm down anytime in the near future. Many doctors, scientists and Lyme disease sufferers feel that long term antibiotics are the best way currently available to treat Lyme disease.

On Wednesday, February 17, 2010, New Hampshire House lawmakers approved a bill that would make it easier for doctors in the state to treat Lyme disease through the use of long term, prescribed antibiotics.

Why is this such a big deal, you may ask? In the past, doctors have been reluctant to prescribe long term antibiotics because many were skeptical of the existence of a chronic form of Lyme disease, primarily because of the flawed guidelines issued by the Infectious Disease Society of America (IDSA) who has consistently ignored scientific evidence that does not agree with their position. In addition many doctors are afraid that the IDSA will go after them and try to revoke their license to practice medicine, as has happened in several cases. With the passage of this bill, New Hampshire doctors will be able to treat their patients as they and their patients feel is best, without any intrusion by the IDSA.

Rep. Jen Coffee (R) of Andover had this to say about passing the bill: “Any medication has the potential to have a problem, but we allow long-term antibiotic use for treatment of acne — acne of all things.” She added, “Why wouldn’t we allow it for Lyme disease?”

Many people don’t think Lyme disease is a big problem, but once they take a closer look at the statistics they find out differently. Believe it or not, more than 25,000 new cases of Lyme disease are diagnosed across the country every year, and since Lyme disease is so frequently misdiagnosed, the true number of cases is most likely much higher. This has led to New Hampshire, as well as several other states, passing legislation to protect doctors who actually try to treat this debilitating disease. The states that have yet to have done so are holding back because they feel that long term treatments need to be studied in more depth, no doubt the result of the confusion caused by the controversy with the IDSA guidelines.

Lawmakers and doctors are not the only ones supporting the bill. Many Lyme disease sufferers have been actively lobbying for such bills to be passed in their state. They are tiered of being told by doctors who follow the IDSA guidelines that it’s all in their heads and they should just go home and suffer. Furthermore, because of these guidelines many insurance companies have began to refuse to pay for antibiotic treatments for chronic Lyme disease, adding more problems to the lives of those who suffer from this disease.

Kathy Kettmann a Lyme disease sufferer and supporter of the New Hampshire bill said: “I couldn’t walk. I couldn’t talk,”… “I was very sick, and to be put in a car for five hours to go to the doctor because we couldn’t get treated in New Hampshire was hard.”

It yet remains to see if the New Hampshire State Senate will pass the bill. It will also be interesting to see if more states follow suit with similar legislation.