Some reports suggest that fibrils can kill neurons at nanomolar doses of A` (74 cheap 800mg nootropil free shipping,91) purchase nootropil discount, but concentrations used in typical nerve cell biology experi- ments exceed 20 M (in total molarity of A`) buy generic nootropil 800mg online. Although this dose may seem high, molarity has little meaning with respect to insoluble assemblies such as fibrils. Because immature or diffuse plaques, thought to comprise amorphous A` supramolecular assemblies, do not trigger local neuronal degeneration (108 110), degenerative effects may depend on particular configurations of aggregated A` (84). The persuasiveness of the A` fibril hypothesis has motivated an intense search for compounds that inhibit fibril toxicity. Several promising fibril- blocker neuroprotectants (111 113) have been found, including certain dyes (84,114,115) and small peptides that act as `-sheet breakers (116). Electron microscopy shows fibrils from aggregated A` (arrows) extend to the plasma membrane of a neuron-like human cell line (arrowheads). Fibril Hypothesis Is Powerful but Imperfect An extensive literature focuses on fibril neurotoxicity. A particular problem with the fibril hypothesis is the imperfect correla- tion between amyloid abundance and dementia. Although postmortem analyses are not optimum for answering questions of cause-and-effect, attempts to correlate pathological markers with dementia have challenged as well as supported the A` fibril hypothesis. Some studies have concluded that decreased synaptic density and the abundance of tangles are more germane than plaques to the progression of dementia. Various explanations have been offered to account for the imperfect correlation (121,122), including the argument that better data analysis and selection of plaque subtype show improved correlation (123). It appears, however, that amyloid plaques can be abundant in individuals without dementia (124 126). Moreover, exam- ined closely in the hippocampus, the majority of neuron loss occurs in the absence of any proximal amyloid (127,128). As an alternative, they hypothesize the presence of small diffusible toxins formed from A`, which might act either intracellularly or extracellularly. Other recent studies as well as earlier works also have reported amyloid-free transgenic mice that exhibit multiple aspects of pathology and behavioral anomalies (60,130 138). In fact, they may reflect a different aspect of A`-evoked pathogenesis, namely, one that involves nonfibrillar A` oligomers. Small Oligomers as Molecular Alternatives to the A` Fibrillar State Nonfibrillar forms of multimeric A` have not yet been detected in transgenic animals. Until recently, these small oligomers were considered transient intermediates, en route to fibrils, but new evidence indicates they exist as independent toxic entities. Stable Oligomers Self-association of A` into subfibrillar structures has been established for both A`42 and A`40. The small oligomers exist in a fibril-free conditioned medium, consistent with biochemical stability. Solutions of synthetic A`40 also form oligomers, but they have been detected only after chemical crosslinking (141). Several studies have now established the presence of small A`42 oligo- mers in human brain tissue. The authors concluded that 10 Klein upregulation of oligomers most likely reflected ongoing amyloidogenesis, but speculated the oligomers might be bioactive. Extending these important findings, Masters, Beyreuther, and their colleagues recently have presented results showing that dementia correlates better with small oligomeric A` than with amyloid (83). The prediction has potential practical value because fibril blockers would be prototypes for rationally designed thera- peutic drugs. The implication, which is of rapidly emerging significance, is that fibrils are not the sole toxic A` entity. Their experi- ments used solutions of synthetic A`42 that contained clusterin as an additional component (32,146). Even at a 5% molar ratio (1 mol clusterin to 20 mol A`42), clusterin caused a major reduction in fibril formation. In fact, the slow-sedimenting molecules formed in A` clusterin solutions were even more toxic than typical fibrils. As a potential modifier of fibril formation in these experiments, clusterin was an apt choice. Clusterin and A`42 thus encounter each other in Alzheimer-afflicted brain parenchyma. Somewhat surprisingly, in contrast to its impact on A`42, clusterin blocks the toxicity of A`40, even at substoichiometric doses (151). Toxicity in slices is quantified by image analysis of dye uptake into living or dead cells (Fig. In this paradigm, clusterin- induced A` toxins are extremely potent, with hippocampal nerve cell death significant even at nanomolar levels of A`. Predominant species comprise A` trimer through pentamer, although molecules as large as 24-mers are detectable (152). Whether the conforma- tions are identical to oligomers detected in vivo is unknown, although certainly plausible. The toxic entities are dimers (153), which reportedly have no direct effect on neurons. The larger A` oligomers, as formed in vitro in the presence of clusterin, also activate glial cells (86). In vivo, scavenger effects associated with high-abundance A`-binding pro- teins may retard fibril formation. Scavenger function, however, cannot explain how proteins such as clusterin block fibril formation at extremely low molar doses, nor explain why some proteins stimulate fibril formation. Differing outcomes with respect to fibrillogenesis suggest that local protein milieu, by influencing A` self-association, could alter the particular course of the disease. Biophysical models of A` fibrillogenesis incorporate the concept of critical concentration (93,163). The apparent critical concentration is in some way affected by the specific impact of proteins. At least two possibilities are appealing, with different mechanisms potentially associated with different proteins. Different chaperones could favor A` conformations that, after release, could foster oligomers or foster fibrils. Precedent for stable, oligomer-favoring conformations is found in the effects of low temperature. The role of peptide con- formation in determining subsequent aggregation state is a phenomenon well established for the pathogenic action of prions (165,166). It is not clear whether A` oligomers or fibrils are thermodynamically more stable, although at low concentrations, oligomers exist in the absence of fibrils. In a second, somewhat related mechanism, an A`-binding protein could act like an anti- gen-presenting protein, holding the monomer within a surface pocket to facilitate interactions that produce oligomers or fibrils. The prion literature provides extensive precedent for mechanisms that require inducible protein conformation states to produce neurotoxic entities (94). Protofibrils exhibit toxicity in assays for neuronal viability and electrophysiological activity (169). Similar triggering might be envisioned for fibrils, perhaps with membrane complications leading to cytotoxicity.
Vitamin D Vitamin D purchase nootropil 800mg overnight delivery, also known as calciferol buy nootropil 800 mg lowest price, is a broad term inclusive of a collection of steroid-like substances such as vitamin D2 (ergocalciferol) and vitamin D3 (cholecal- ciferol) purchase nootropil 800mg. Vitamin D is only found in animal sources and can be produced by the body with exposure to ultraviolet radiation. Reactive changes in the bone underlying, and adjacent to, damaged cartilage are an integral part of the osteoarthritic process (45 51). Other phenomena, such as osteophyte (bony spur) formation may be attempts to repair or stabilize the process (54,55). Animal studies suggest that vitamin D might also have direct effects on chondro- cytes in osteoarthritic cartilage. Although these findings emanate from animal studies, they serve as preliminary data that these relationships may also exist in humans. During bone growth, vitamin D regulates the transition in the growth plate from cartilage to bone. It had been assumed that chondrocytes in developing bone lose their vitamin D receptors with the attainment of skeletal maturity. Additionally, they demonstrated the presence of nuclear receptors for 24,25-dihydroxy-cholecalciferol in chondrocytes (59). Thus, in vitro vitamin D has both enhancing and suppressive roles in the regulation of chondrocyte products. Because these could have differential effects on cartilage, and the net overall effect is unknown, Tetlow et al. Biopsies of hip patients had significantly fewer receptor-positive nuclei compared with those of back surgery patients (p = 0. They measured serum vitamin D levels in 237 subjects randomly selected from 6,051 women who had pelvic radiographs taken at both the baseline examination and after 8 years of follow-up. In both studies, worsening was defined by radiographic tibiofemoral joint-space loss. The mean vitamin D level was 20 ng/mL at baseline in both studies, and about 20% of knees exhibited joint-space loss during the observation periods. They found associations of use of alendronate and/or estrogen with lower structural lesion and lower pain scores (70). However, as pointed out by DeMarco (71)7, the original report did not account for potential influence of vitamin D on these associations. The most common and biologically active form is -tocopherol (5,7,8 tri-methyltocol). In the human body, the ester is rapidly cleaved by cellular esterases making natural vitamin E available. Vitamin E has diverse influences on the metabolism of arachadonic acid, a proin- flammatory fatty acid found in all cell membranes. Like vitamin C, vitamin E affected the activ- ities of lysosomal enzymes: It decreased the activities of arylsulfatase A and of acid phosphatase in cultures of human articular chondrocytes (75). In a small 10-day crossover trial on spondylosis, 600 mg of vitamin E per day was superior to placebo as assessed by a patient questionnaire (84). One trial suggested that vitamin E was no less efficient than diclofenac in decreasing pain. Loss of medial and lateral tibial cartilage was similar in subjects treated with vitamin E and placebo (e. There were no significant differences between the vitamin E- and placebo-treated groups in improvement of symptoms from baseline. However, there are limitations that should be considered in the interpretation of these results. First, this study was powered to detect a 50% reduction in the rate of cartilage loss in the treatment arm. This effect size likely was an over-estimate of any effect that could have been expected from vitamin E over a 2-year follow-up period. This is problematic because cartilage volume uncorrected for surface area lacks construct validity (88). Furthermore, cartilage volume has not been tested for sensitivity to change, thus it is unclear whether a real change in cartilage volume within a given individual can be distinguished from measurement error. According to the best-evidence synthesis, the authors concluded that there is no evidence of symptom-modifying efficacy for vitamin E and some evidence of inefficacy regarding structure-modifying effects (90). Vitamin K The primary form of vitamin K, a fat-soluble vitamin, in the diet is phylloquinone (vitamin K1), which is concentrated in dark green leafy vegetables and vegetable oils. Low dietary intake of vitamin K is common, and studies evaluating biochemical measures of vitamin K status suggest that inadequate intake of vitamin K is widespread among adults in the United States and the United Kingdom (91,92). Although it is not known to have anti-oxidant effects, vitamin K does have bone and cartilage effects, which may be relevant for osteoarthritis. Post-translational - carboxylation of glutamic acid residues to form -carboxyglutamic acid (Gla) residues confers functionality to these Gla proteins (93). Multiple coagulation, bone, and cartilage proteins are dependent on vitamin K because the Gla residues are required for these proteins to function appropriately. The vitamin K-dependent -carboxylation of these bone and cartilage proteins is important for their normal functioning. Gas-6, through its interactions with the Axl tyrosine kinase receptor, prevents chondrocyte apoptosis and is involved in chondrocyte growth and development (94). Low levels of vitamin K could lead to inadequate levels of functional Gas-6, contributing to increased chondrocyte apoptosis and attendant mineralization. Another Gla protein is osteocalcin, the most abundant noncollagenous protein in bone, and a potent inhibitor of hydroxyapatite mineralization. These abnormalities may reflect a process similar to osteophyte formation because both cartilage plate abnormalities and osteophyte formation involve endochondral ossification. They demonstrated an association between higher vitamin K intake and lower osteophyte prevalence, but the association was not significant with prevalence ratios of osteophytes from lowest to highest vitamin K intake quartiles of 1. The prevalence of hand and knee osteophytes in those in the highest plasma phyllo- quinone quartile was 40% lower than in those in the lowest quartile. No significant associations were noted for control nutrients, vitamins B1 and B2, suggesting that a healthy lifestyle does not account for these results. If a relationship between vitamin K and osteophytes does exist, the public health benefits could potentially be enormous. It seems reasonable to expect that plasma levels of micronutrients are more accurate measures compared with dietary intake measures, lending more credibility to the latter study supporting an association between vitamin K and osteophytes. Selenium and Iodine: Studies of Kashin-Beck Disease Selenium is an integral component of iodothyronine deiodinase as well as glutathione peroxidase. Kashin-Beck disease is an osteoarthropathy of children and adolescents, which occurs in geographic areas of China in which deficiencies of both selenium and iodine are endemic.
These medications are difficult to take as they are either in the form of large tablets or a dissolvable powder generic nootropil 800mg on-line. While it is quite effective 800 mg nootropil with visa, the substantial side effect profile of Niacin limits its use purchase nootropil without a prescription. Side effects include hepatic failure, myopathy, glucose intolerance, and hyperuricemia. Fish oil or omega-3 fatty acids: Fish oils are fatty acids that lower plasma triglyc- erides levels and have antithrombotic properties. Statins are better tolerated than other pharmacologic options and can lower total cholesterol by 20 50%. There are rare reports of rhabdomyolysis and there is some risk of teratogenicity. Stains should be used with caution in females of reproductive age and these patients should be specifically counseled about the risks of the medication in pregnancy. Cholesterol absorption inhibitors: This is a relatively new class of drug, introduced in the 1990s, that inhibits cholesterol absorption from the intestinal lumen. Though these medications may be better tolerated than bile acid sequestrants, there is only limited data for their use in pediatrics. His mother reports that her husband died suddenly of a myocardial infarction at age 37 and was known to have elevated cholesterol. The boy is quite active and participates in soccer and basketball without cardio respiratory complaints. He is likely a heterozygous, as total cholesterol for patients with homozygous mutations can be as high as 700 800. Because this diagnosis confers a high risk of early cardiovascular disease, intervention is necessary at this time. The patient should be started on a low cholesterol diet and pharmacotherapy should be initiated. Dietary modification alone is not effective in lower total cholesterol in this disorder. The patient will then need hepatic enzymes checked in 1 month, then every 6 months after that. As rhabdomyolysis is a rare complication of statin therapy, any new muscle soreness, especially soreness not related to exercise, needs to be taken seriously. A maternal grandmother suffered a stroke at age 60 and a paternal grandfather has diabetes, hypertension, and is status post coronary artery stent placements at age 50. The patient is not taking gym this year in school and has been overweight since age 8. Neurological examination is grossly normal; however, you notice that she has some difficulty maneuvering on and off the examination table. Other laboratory values (thyroid function tests, renal and hepatic function panels) are normal. She is at high risk for development of diabetes and given her history of snoring, may already have obstructive sleep apnea. The first step in management of this patient is a comprehensive weight reduction program that includes dietary modification and increased physical activity for at least 3 months. This patient would benefit greatly from a family approach to care given her parents are also obese. At least three ambulatory measurements are required before considering pharmacotherapy. In addition, given her size, it may be appro- priate to use either a large adult cuff or potentially a thigh blood pressure cuff. Her possible sleep apnea should be addressed with further questions regarding her sleep and diagnostic sleep study. Pharmacotherapy targeted at her hypertension and hyperlipidemia could be considered after 3 months if there is no improvement. Serum levels should be obtained if there is lack of compliance, acute changes in renal function, or signs of digoxin toxicity. The half life of the medication is very long and therefore, its effect lasts days or even weeks after discontinuation. See Arterial switch operation clinical manifestations, 161 162 Asplenia syndrome, 258 echocardiography, 162 164 Asthma. Neither the European Commission nor any person acting on its behalf is responsible for any use that might be made of the following information. Europe Direct is a service to help you fnd answers to your questions about the European Union Freephone number (*): 00 800 6 7 8 9 10 11 (*) Certain mobile telephone operators do not allow access to 00 800 numbers or these calls may be billed. Another object of the working parties is to support the Commission in their work and to highlight gaps and special topics in their field of action. The topics to be discussed in working parties are normally very broad and therefore it was decided to build up subgroups the so called task Forces. One of the task forces is the Task Force on Major & Chronic Diseases which is a subgroup of the working party Mortality and Morbidity. In 2006 the Task Force Major & Chronic Diseases decided to give better visibility to their extensive work. It was written on voluntary basis by expert members of the Task Force Major & Chronic Diseases. The report provides an overview of the main topics which were discussed during the different meetings of the task force. It also highlights the results and ongoing activities of different projects which were or are funded by the European Commission. The report on Major and Chronic Diseases will improve information in the area of major and chronic diseases. I think that this report will give the necessary visibility and attendance that the task force on Major and Chronic Diseases worked to achieve. Based on the positive reactions of those project leaders, who were able to find the time and resources to contribute (either alone or in cooperation with their expert colleagues), a disease based division of chapters was made. Authors were asked to show the contribution of their projects to European Public Health Information, as much as possible according to a pre-structured template. It was left to the decision of the authors to use those data which were, in their opinion, either of the best quality, or most feasible to use within the time they could make available for writing their contribution to this report. Firstly, the contents of this report are a reflection of the authors findings and opinions, and do not necessarily reflect the opinion or the position of the European Commission. If necessary in terms of copyright, permission for publication was obtained for the non- public materials (tables, figures) used in this report. The structure underlying the System can be regarded as a matrix: collecting and disseminating comparable, valid data requires different actions at different levels in national and supranational public health monitoring systems, and this needs to be 7 done for multiple diseases and conditions. In the former Public Health Programme the development of indicators for different groups of diseases and conditions has received ample attention. Existing data sources have been used as much as possible in setting up this System. Making an inventory of available data (such as from morbidity registers, health surveys, hospital discharges etc.
Following the first few breaths order cheap nootropil line, inflation of the lungs leads to a decrease in pulmonary vascular resistance and a brisk increase in pulmonary blood flow order nootropil online. When pulmonary venous return is obstructed buy nootropil with a mastercard, the increase in pulmonary blood flow exacer- bates the pulmonary edema. Following initiation of prostaglandin infusion, the duct will dilate and further augment pulmonary blood flow, further potentiating pulmonary venous obstruction. There is lack of R wave progression in the precordial leads, where the R wave should become taller and taller from V1 to V6, suggesting right ventricular dominance or dextrocardia. Diffuse T wave flattening indicates a repolarization abnormality and is suggestive of ischemia Patients who are born without prenatal diagnosis can have a dramatic presenta- tion of right atrial isomerism, secondary to significantly obstructed pulmonary outflow and/or pulmonary venous obstruction. This infant underwent segmental cardiac evaluation by echocardiography, which found: Cardiac position and direction of apex: Dextrocardia with apex to the right Systemic venous connections: Bilateral superior vena cava Absent coronary sinus Inferior vena cava to right-sided atrium Bilateral hepatic venous connections Pulmonary venous connections: Total anomalous pulmonary venous return to a systemic vein below the diaphragm Atrial situs: Right atrial appendage isomerism bilateral broad-based triangular atrial appendages 268 S. He was born by spontaneous vaginal delivery at 41-5/7 weeks and had incomplete prenatal care. A soft, 2/6 systolic flow murmur is noted both at the right and left sternal border. Pulmonary vascularity is slightly increased, suggesting increased pulmonary blood flow. The gastric bubble is on the right and the liver is on the left indicating situs inversus of abdominal structures Discussion The dextrocardia, right-sided gastric bubble, and left-sided liver confirm a condi- tion of abnormal left right positioning. The differential diagnosis includes: Dextrocardia with situs inversus (rightward heart with mirror-image arrange- ment of the thoracic and abdominal viscera), particularly since bilateral short bronchi cannot be confirmed on chest X-ray. If this were the diagnosis and the patient subsequently developed recurrent pulmonary infections, sinusitis, and bronchiectasis, a diagnosis of Kartagener syndrome should be considered. It is the reduced systemic oxygenation, tachypnea, and growth failure which raise the concern for associated intracardiac malformation. Left isomerism more commonly presents with signs and symptoms of increased pulmonary blood flow (tachypnea), growth failure, and signs of congestive heart failure (livedo reticularis suggests increased systemic vascular resistance associated with congestive heart failure). This infant was referred to the hospital for cardiology consultation where echocardiogram confirmed left atrial isomerism (Fig. Segmental analysis demonstrated: Cardiac position and direction of apex: Dextrocardia with apex to the right 270 S. He then underwent single ventricle pallia- tion with a pulmonary valvectomy and placement of a systemic-to-pulmonary shunt. He presented to the office at 4 months of age with lethargy and poor feeding and was found to be responsive, but bradycardic, with a heart rate of 58. Murmurs may not be appreciated by auscultation; how- ever, the second heart sound is single. Definition Hypoplastic left heart syndrome is a cyanotic congenital heart disease presenting in the first week of life. The mitral valve is severely stenotic or atretic leading to small or hypoplastic left ven- tricle and severely stenotic or hypoplastic aortic valve. The ascending aorta tends to be hypoplastic and slightly enlarges towards the aortic arch with a normal S. Blood travels in a retrograde fashion through the aortic arch and all the way back to the ascending aorta to provide blood flow to the coronary arteries. Often, the mitral and aortic valves are not completely atretic, but severely hypoplastic. In the neonatal period, maintaining the patency of the ductus arteriosus is crucial for survival (Fig. Pathophysiology With severe hypoplasia of the left heart, there is no forward flow across the aortic valve through the ascending aorta. The blood flows in a retrograde fashion through the ascending aorta to supply the brachiocephalic branches and the coronary arteries. Blood ejected from the right ventricle supplies the pulmonary artery as well as the systemic circulation. The pulmonary circulation has a lower vascular resistance (about 3 Wood units) compared to the systemic vascular resistance (about 25 Wood units). This significant difference in resistance will favor blood flow into the pul- monary system leading to excessive pulmonary blood flow and eventual pulmonary edema. The comparatively limited blood flow to the systemic circulation will result in poor systemic cardiac output and, in extreme cases, can manifest as cardiogenic shock. In view of mitral atresia, the blood in the left atrium shunts across atrial septal defect to the right atrium. Blood flow to the aorta is supplied through the ductus arteriosus Atrial septal communication has to be present for survival in these patients. Pulmonary venous return to the right atrium cannot flow into the left ventricle due to mitral and/or left ventricular hypoplasia. The phenomenon of pulmonary edema and cardiogenic shock will become even more pronounced when the ductus arteriosus starts to close around 2 4 weeks of age. Without an adequate right to left shunt, systemic cardiac output will drop and right sided heart failure will develop. The patient will present with severe respiratory distress and poor perfusion evidenced by ashen color, cool extremities, and weak peripheral pulses. Death is imminent unless ductal patency can be maintained, usually with prostaglandin infusion. Busse may be noted early on, especially with increase in activity such as during feeding or agitation. At about 2 4 weeks of age, patients present with increasing lethargy, decreased peripheral perfusion with ashen color or cyanosis and increasing respira- tory distress secondary to pulmonary edema. On examination, patients have poor peripheral pulses and perfusion with signifi- cant prolongation of capillary refill. Hepatomegaly may be noted along with a hyperactive precordium, prominent right ventricular impulse (right lower sternal border), and a lack of apical impulse. On auscultation, the first heart sound is normal, but the second heart sound is single due to aortic atresia. In severe cases, presentation is that of complete circulatory collapse and shock which may be mistaken for sepsis. Patients are cyanotic with poor or nonpalpable pulses and usually no audible murmurs. Chest Radiography The data obtained from chest radiography is often nonspecific and of limited use in diagnosis. However, absence of the apical portion of the cardiac silhouette may be suggestive of left ventricular hypoplasia. The heart size may be normal or enlarged and the pulmonary vasculature may be normal or increased (Fig. Since a normal newborn s electrocardiography also has increased right ventricular voltage, this finding may be difficult to interpret in this age group (Fig. Second heart sound is single due to aortic valve atresia 23 Hypoplastic Left Heart Syndrome 277 Fig. The apex of the cardiac silhouette is abnormal due to hypoplasia of the left ventricle.
Travelers may consult the family doctor with several vesicular lesions that may be diagnosed as bacterial order nootropil 800 mg mastercard, notably staphylococcal order nootropil with american express, infection for which ucloxacillin is prescribed buy nootropil 800mg line. Typical risk behavior is contact with dogs that are important trans- port hosts, bringing infected ticks to man. Dogs are only transient reser- voirs, other reservoirs probably being wild rabbits and hares, possibly also hedgehogs and other small rodents . These diseases are char- acterized by fever, a maculopapular rash appearing within 2 3 days after 120 Imported Skin Diseases onset, and an inoculation eschar at the site of the tick bite. In published series of cases the eschar is not found in 14 40%  but careful exam- ination is necessary as they may be localized on scrotum, between but- tocks, in axillae, at the scalp. Multiple eschars do occur but are rare; multi- ple eschars should raise the suspicion of infection by Rickettsia aeschlimanii that is transmitted by Hyalomma spp. Comparable diseases are Siberian, or North Asian and Queensland tick typhus, Japanese spotted fever among others. With prompt recognition and treatment, death should be uncommon, yet 3 5% of cases reported in the United States in recent years have been fatal . Risk factors for severe disease and death include delayed diagnosis and treatment and age above 40. In recent years infections by Rickettsia parkeri, transmitted by Amblyomma ticks were described from the United States and South American countries. Scrub typhus Scrub typhus is endemic in rural South and Southeastern Asia and the Western Pacic. Man is infected by the bite of larval trombiculid mites (chiggers) that typically bite humans on the lower extremities or in the genital region. With continued global warming, the fungus Geomyces destruc- tans has decimated fruit bat populations worldwide; as a result more mosquitoes and mosquito-borne viral illnesses can be expected to sur- face. Viral skin diseases vary in their clinical manifestation, geographic Imported Skin Diseases, Second Edition. Here we have reviewed the most prominent viral infections with specic attention to their accompanying cutaneous manifestations, diagnosis, and treatment. Chikungunya virus Epidemiology In 2005 and 2006 there were two major outbreaks of the chikungunya virus in India and Reunion (an island in the Indian Ocean). Subsequently the transmission of the disease has occurred in separate waves to virtu- ally all continents, including North America (United States) and Europe (France and Italy). In 2007, chikungunya fever was transmitted to Italy for the rst time, presumably from an Indian man visiting relatives. This arthropod-borne virus often presents with the triad of fever, arthralgia, and rash. In most cases, resolution of symptoms occurs 10 13 days after initial exposure; however, myalgia and arthralgia can persist for up to 1 year . Elimination of breed- ing sites via insecticides and use of mosquito nets are effective prevention modalities. In 2009, the rst case in 75 years was reported in Florida with a subsequent 65 cases conrmed in 2010. Over 21,000 cases have been reported in Puerto Rico, making it the largest outbreak in history . Infection with one strain can only produce lifelong immunity to that par- ticular strain. Dengue is commonly called break-bone fever because of the associated debilitating joint and muscle pain. Currently, there is no vaccine available but progress on a tetravalent vaccine, which will include four different strains of the virus, is being made . The use of insecticides and adequate solid waste disposal are effective means of prevention. The virus most likely orig- inated in Africa and has had repeated outbreaks in the Americas until the twentieth century. Despite introduction of the vaccine in the twen- tieth century, the disease was imported by a Belgian traveler returning from Gambia in 2001, and from Suriname to the Netherlands in 2000 . Clinical features The disease initially manifests as a nonspecic febrile illness that usually remits a week after exposure. Diagnosis In early disease, viral culture is the preferred method of diagnosis, but serology (IgM or fourfold rise in IgG) can also be used . Immunization with the live attenu- ated vaccine is recommended 7 10 days before travel to endemic regions; boosters are required every 10 years . In 1999, a strain of West Nile virus prevalent in Israel was imported into New York City, and since then the virus has spread across the United States becoming endemic . It is now the most common cause of epidemic meningoencephalitis in North America . Clinical features Approximately 80% of patients infected with West Nile virus are asymp- tomatic . Of the remainder, most develop West Nile fever, a nonspecic febrile syndrome, which can include a macular rash on the trunk that may desquamate. Neurologic involvement is more common in the elderly and the immunosuppressed . Treatment The disease is self-limited and treatment of neurologic disease is support- ive. Without a current vaccine, prevention is key, directed at avoiding mosquitoes . Hemorrhagic fevers Ebola and Marburg Epidemiology Ebola and Marburg viruses comprise the Filoviridae family and cause deadly and virtually identical hemorrhagic disease. An isolated case of Ebola occurred via an accidental needlestick in 1976 in a United Kingdom laboratory processing material from patients in Africa. Since then, only evidence of the Ebola- Reston strain, which has never caused disease in humans, has appeared in countries outside of Africa. Marburg was rst identied in 1967 in Marburg, Germany, where a small outbreak occurred in laboratory staff Viral Diseases 129 handling African monkeys. In 2008, imported Marburg occurred in an American and a Dutch patient, both of whom had recently traveled to Uganda . Bleeding is frequent, characterized by generalized petechiae on the trunk and extremities. Disease should be suspected in individuals who recently traveled to Africa or work with primates that may be infected. The South American hemorrhagic fevers have remained limited to their respective countries in South America. Unlike other hemorrhagic fevers, onset is insidious; initial symptoms include fever and pharyngitis. Capillary leak syndrome is the hallmark of disease, causing facial but not peripheral edema, as well as pleural and pericardial effusions . Imported cases occur in travelers to endemic countries in West Africa, including Nigeria, Sierra Leone, and Burkina Faso. Treatment Treatment is mainly supportive; however ribavirin has been shown to reduce mortality in Lassa fever .
By I. Sinikar. Mount Vernon Nazarene College.