- April 3, 2020
Thisis an infectious disease commonly referred to as borreliosis, and thecausative agent is a spirochete known as Borrelia.Transmission occurs through the bite of a vector, often ticks whichbelong to the genus Ixodes. Before infection, there must be anattachment of the tick on the host for at least some duration oftime. Individuals who are at risk include those who inhabit woodedand grassy areas where infected ticks are likely to thrive. Causativebacteria can be divided into different subgroups Borreliagarinii, Borrelia afzelii, Borrelia mayonii, and Borreliaburgdorferi.Another risk factor is that of having a bare skin (Merino etal.,2015). Ticks are likely to attach effortlessly on an exposed skin.Thus, it’s mandatory for those inhabiting infested areas to protectthemselves from possible tick bites by dressing in clothes thatadequately cover their body. Additionally, failure to appropriatelyand urgently remove ticks may initiate the entry of the bacteria intothe bloodstream. Lyme disease can affect any organ within the body,including the heart, muscles and even the nervous system (Shapiro,2014). The probability for misdiagnosis is very high hence leading totreatment delays thereby contributing to the unchecked progression ofthe disease. The purpose of this research paper is to provide anin-depth understanding of illness in regards to the signs andsymptoms, the pathogenic action of bacteria and finally the treatmentand defensive mechanisms.
There’susually a variance in how the signs and symptoms appear depending oneither the early stage or late stage
Commonly,a confined infection occurs at the spot of the bite before thedisease spreads to other organs. Most individuals in the early stageof the disease develop a characteristic circular rash, referred to aserythema chronicum migrans, following a tick bite. It may take threeto thirty days to occur following the tick bite. It has a similarappearance to a bull’s eye on a dart board. Even though the rash ispainless, it has a reddish appearance with a warm feeling (Merino etal.,2015). Additionally, there is a slight elevation on the edges of theinfected area. There’s a significant variance in the size of therash due to the possibility of expansion in the coming days or weeks.The typical size is approximately fifteen centimeters however, thesize may be larger or smaller. Most individuals may develop rashes indifferent parts of the body. There’s also a proportion of infectedpeople who do not develop the rash hence leading to misdiagnosis ofthe disease (Shapiro, 2014). The disease is likely to progress to thelate stages even in scenarios where there is non-development of therash. Other typical signs associated with the illness includeflu-like symptoms such as the feeling of tiredness, pain in themuscles and joints, chills, fever, headaches and neck stiffness.
Ifthe disease is left untreated or insufficiently given propertreatment, there is a possibility of the development of furthercomplicated symptoms which might result in chronic infection. In thislate stage, the disease is characterized by a full blown infectionwhereby most organs are infected. The typical symptoms includeswelling of the joints, commonly referred to as inflammatoryarthritis. The nervous system is also affected leading to thenumbness of limbs, paralysis of facial muscles, in addition to memoryloss (Merino etal.,2015). The heart is also affected leading to myocarditis,pericarditis, blockage and failure in the functioning of the heart.Furthermore, the brain and spinal cord are affected as a result ofthe inflammation of the surrounding membranes. This leads to thedevelopment of a stiff neck and severe headaches. In case treatmentis initiated late, these symptoms are likely to persist.Additionally, other patients are also likely to develop symptomswhich resemble fibromyalgia (Shapiro, 2014). It`s commonly referredto as the post-infectious disease. Frank psychosis may also resultfrom infection with illness and the failure to initiate earlytreatment. Even though the knee is commonly affected by Lymearthritis, the possibility of other joints being infected is alsohigh, for example, elbows and ankles.
Mechanismsof pathogenic action at cellular and molecular level
Afteran individual has been bitten by a tick of the genus Ixodes which isalready infected, transmission occurs when the saliva of the tickcontaining the spirochaetes is injected into the skin as they feed.Normal immune responses to bites are disrupted due to the presence ofdeactivating components in the saliva. The infectious spirochetes areconclusively established as a result of this accorded protection. Themultiplication process is initiated hence leading to the spread ofthe infection in the skin resulted in the erythema migrans, thetypical bull’s eye rash. The inflammatory response emanating fromthe immune system contributes to the reddish appearance of the rash.However, this inflammatory response lacks the much-needed assistanceof the neutrophils due to the failure of their materializationprocess (Hammerschmidt etal.,2014). This, therefore, means that the spirochaetes continue tomultiply as the neutrophils which are charged with inhibiting thereplication of bacteria are no longer functional. The tick salivacomprises of the protein plasmin which prevents the visibility of thespirochaetes to the immune system hence the non-convergence of theneutrophils at the infection site.
Despitethe production of antibodies by Borreliaburgdorferi,the efforts of the immune system are confounded by the plasminproduction. Furthermore, the surface proteins are not expressed bythe spirochaetes hence they are not under attack from theantibodies. Change in the variable major protein-like sequence (VIsE)plays a significant role in the avoidance of detection through thedeactivation of some components of the immune system, for example,complement. The bacteria may also inhabit the extracellular matrix inthe body making it inaccessible for the immune cells (Brisson etal.,2013).
Thedevelopment of autoimmune infections is possible due to the tacticsemployed by the bacteria. Initiation of the chronic inflammatoryresponse following exposure to the bacteria leads to damage to thenormal tissues as a result of molecular mimicry used by the bacteriato avoid recognition. The immune system may be tricked to attackhealthy body tissues hence a reason detailing the chronic symptomstypical for most patients even after antibiotic therapy. Theproduction of antibodies against the body’s cells is likely tocontinue even after elimination of Borreliabacteria (Petnicki-Ocwieja and Brissette, 2015). This explains thereason behind the persistent symptoms such as joint pains.
Treatmentof a patient follows the stage and clinical manifestations of Lymedisease. These will guide the selection of antibiotics, method ofmanagement and the period of therapy. Also taken into considerationare allergic conditions or associated medical conditions. Thepossibility of therapeutic success increases following the promptinitiation of antibiotics. Amoxicillin, Doxycycline, and cefuroximeaxetil are the preferred antibiotics for oral therapy. Theintravenous drug administration may be initiated in individuals withcardiac or neurological forms of the illness. Penicillin andceftriaxone are commonly used for this purpose. In instances wherecarditis is involved, the only remedy is to institute prompttreatment through the use of effective antibiotics. Additionally, atemporary cardiac pacing may be required for those withatrioventricular blockage as a result of Lyme infection (Diuk-Wasseretal.,2012). This may also be applied to those patients experiencing aheart blockage. Notably, some patients may experience symptoms ofarthritis even after treatment. This is a common occurrence due toautoimmunity. Retreatment is not necessary unless the symptomsworsen. A combination of nonsteroidal anti-inflammatory drugs(NSAIDs) and hydroxychloroquine is needed for treatment. In the caseof persistence, inflammatory arthritis may be eradicated throughsynovectomy. These antibiotics may also lead to certain side effects,for example, the skin becomes sensitive to sunlight. This will,therefore, demand that the patients avoid prolonged sunlightexposure.
Regardingprevention, it is prudent to realize that Lyme disease has novaccine. Therefore, it’s mandatory to take the necessaryprecautions and preventive mechanisms when visiting areas that aretick infested. The risk of infection can be reduced by avoiding bushyareas and sticking to the established footpaths. Wearing theappropriate dress code is also vital. This comprises of long sleevedshirts with trousers that are tucked into the socks. Beneficially,the clothes should also be colored to allow for easier spotting of atick (Diuk-Wasser etal.,2012). Insect repellants may be applied on top of the exposed skin.At the end of the day out in the woods, it’s crucial to inspect forticks to ensure none is brought home. Specific attention should begiven to children and pets.
Themain aim of this paper is to promote the advancements in Lyme diseaseresearch. There is a need for further research on Lyme disease andother associated tick-borne illnesses to ensure accurate diagnosisand treatment. The research also enlightens the evasion mechanismsused by the spirochaetes to avoid detection by the immune system.Furthermore, the paper aims at improving our understandingneurological, rheumatologic and immunological effects of the diseaseover time with the goal of reducing progression towards chronic Lymedisease. As for me, the information from this paper will guide me onthe best preventive mechanisms to avoid contact with infective ticks.As the common saying goes, prevention is better than cure.
Brisson,D., Zhou, W., Jutras, B. L., Casjens, S., & Stevenson, B. (2013).Distribution of Lyme disease spirochete cp32 prophages and naturaldiversity among their lipoprotein-encoding erp loci. Appliedand Environmental Microbiology,AEM-00817.
Diuk-Wasser,M. A., Hoen, A. G., Cislo, P., Brinkerhoff, R., Hamer, S. A.,Rowland, M., & Tsao, J. I. (2012). Human risk of infection withBorreliaburgdorferi,the Lyme disease agent, in eastern United States. TheAmerican journal of tropical medicine and hygiene,86(2),320-327.
Hammerschmidt,C., Koenigs, A., Siegel, C., Hallström, T., Skerka, C., Wallich, R.,& Kraiczy, P. (2014). Versatile roles of CspA orthologs incomplement inactivation of serum-resistant Lyme disease spirochetes.Infectionand immunity,82(1),380-392.
Merino,O., Alberdi, P., de la Lastra, J. M. P., & de la Fuente, J.(2015). Tick vaccines and the control of tick-borne pathogens. Thebiology and ecology of ticks shape the potential for the transmissionof zoonotic pathogens.,93.
Petnicki-Ocwieja,T., & Brissette, C. A. (2015). Lyme disease: recent advances andperspectives. Frontiersin cellular and infection microbiology,5.
Shapiro,E. D. (2014). Lyme disease. NewEngland Journal of Medicine,370(18),1724-1731.