Epidemic Form Research Articles

Heparin-induced anaphylactic and anaphylactoid reactions: two distinct but overlapping syndromes

Background: Heparin-induced anaphylactic and anaphylactoid reactions are of increasing clinical and scientific interest, particularly given the recent identification of a syndrome of heparin-induced anaphylaxis due to oversulfated chondroitin sulfate (OSCS), a contaminant in certain heparin preparations. However, heparin-induced anaphylactoid reactions also have been reported to be a consequence of immune-mediated heparin-induced thrombocytopenia (HIT). Objective: To summarize the clinical features and pathophysiology of two distinct disorders, HIT-associated anaphylactoid reactions as well as anaphylaxis resulting from OSCS-contaminated heparin. Methods: We review literature describing these two types of heparin-induced anaphylactic and anaphylactoid reactions, and seek potential pathophysiologic links between them. Results: Intravenous bolus heparin administered to patients with circulating ‘HIT antibodies’, usually as a result of recent heparin therapy, can produce anaphylactoid reactions, probably as a consequence of in vivo activation of platelets and, possibly, leukocytes. Affected patients often evince fever/chills, hypertension and/or acute respiratory compromise (‘pseudo-pulmonary embolism’). In contrast, heparin-induced anaphylaxis is caused by activation of the contact system, with formation of vasoactive kinins (bradykinin, des-arg9-bradykinin). This latter syndrome has been linked in an epidemic form to administration of OSCS-contaminated heparin; these reactions feature prominent hypotension and laryngeal edema. Hemodialysis patients are at increased risk for both syndromes. There is evidence that OSCS-contaminated heparin itself increases the risk of HIT compared with non-contaminated heparin. Conclusion: Two distinct syndromes of heparin-induced anaphylaxis and anaphylactoid reactions exist. These seem to share certain epidemiologic features, given that OSCS-contaminated heparin can produce anaphylaxis through contact system activation but also could increase risk of HIT and HIT-associated anaphylactoid reactions.

Routine Supplement of Prebiotics and Probiotics to Newborn Infants Is Not Recommended: In Reply

Dr Shafai considers our study on probiotics and prebiotics (synbiotic) in breastfed infants unethical. The world-wide allergy epidemic forms a great socioeconomic burden for societies and families, and exclusive breastfeeding (alone) has failed to solve the problem. The evidence of breastfeeding in the prevention of allergies is controversial and may depend of heredity.1,2 We performed the randomized, placebo-controlled study on probiotics and prebiotics because these agents had been reported to be promising in the prevention of allergic diseases in …

Was encephalitis lethargica a post-influenzal or some other phenomenon? Time to re-examine the problem

Encephalitis lethargica (EL) was first reported in 1917 in central Europe. It became epidemic in the winter of 1918/1919 concurrently with the pandemic of influenza, and by then had reached Russia and North America. It spread throughout the world in epidemic form, mainly in the succeeding winters, up to 1927. By then about 65 000 cases had been reported, although the true number worldwide can only be guessed at. EL mortality was about 30% in the acute stage, and similar during recurrences. Half of the survivors had persistent or recurrent neuro-psychiatric illness, with Parkinsonism a frequent end stage. Most contemporary observers attributed EL to a virus and some believed it was specifically a post-influenzal complication. The epidemiology of EL mostly points to an infective cause, e.g. a seasonal respiratory or gastrointestinal virus with infrequent encephalitic expression but the ability to persist, flare and progressively damage the brain. However, any link with the influenza virus strain of 1918/1919 remains hypothetical. The aetiological theories that have been applied to EL are reviewed and the question is raised whether broader laboratory investigation might now reveal a continuing low endemicity of EL and identify its cause.

Co-evolution positions and rules for antigenic variants of human influenza A/H3N2 viruses

BackgroundIn pandemic and epidemic forms, avian and human influenza viruses often cause significant damage to human society and economics. Gradually accumulated mutations on hemagglutinin (HA) cause immunologically distinct circulating strains, which lead to the antigenic drift (named as antigenic variants). The "antigenic variants" often requires a new vaccine to be formulated before each annual epidemic. Mapping the genetic evolution to the antigenic drift of influenza viruses is an emergent issue to public health and vaccine developmentResultsWe developed a method for identifying antigenic critical amino acid positions, rules, and co-mutated positions for antigenic variants. The information gain (IG) and the entropy are used to measure the score of an amino acid position on hemagglutinin (HA) for discriminating between antigenic variants and similar viruses. A position with high IG and entropy implied that this position is highly correlated to an antigenic drift. Nineteen positions with high IG and high genetic diversity are identified as antigenic critical positions on the HA proteins. Most of these antigenic critical positions are located on five epitopes or on the surface based on the HA structure. Based on IG values and entropies of these 19 positions on the HA, the decision tree was applied to create a rule-based model and to identify rules for predicting antigenic variants of a given two HA sequences which are often a vaccine strain and a circulating strain. The predicting accuracies of this model on two sets, which consist of a training set (181 hemagglutination inhibition (HI) assays) and an independent test set (31,878 HI assays), are 91.2% and 96.2% respectively.ConclusionOur method is able to identify critical positions, rules, and co-mutated positions on HA for predicting the antigenic variants. The information gains and the entropies of HA positions provide insight to the antigenic drift and co-evolution positions for influenza seasons. We believe that our method is robust and is potential useful for studying influenza virus evolution and vaccine development.

Chikungunya in West Bengal, India

Fever of unknown origin broke out in several districts of West Bengal, from August 2007 to December 2007. The cases were suffering from high fever, severe joint pain lasting for several weeks after clinical cure and appearance of skin rashes. Patients' sera were collected at least five days after fever and were analyzed to detect specific IgM antibodies. A total of 800 patients were investigated and 321 (40.13%) were found to be reactive for Chikungunya antibodies. Of the patients, 66% were male. Predominant signs and symptoms observed in the sero-positive cases were fever (100%), arthralgia (96%) and diffuse erythematous skin rash (94%). Of the patients, 3% had haemorrhagic manifestations. Re-emerging Chikungunya virus spread in epidemic form in several districts of West Bengal after a gap of four decades.

Redes: um olhar sistêmico para a epidemiologia de doenças transmissíveis

The direct or indirect physical contact between human beings as a basic condition for the transmission of infectious diseases stimulated epidemiologists to put forth great efforts to understanding and describing the process of human contacts. It is through these contacts that disease spreads over populations and emerges, at the systemic level, in the form of epidemics. During the 20th century, many researchers dedicated themselves to revealing the population patterns that favor or not the emergence of epidemics and their temporal and spatial dynamics. The first insights came from population models adapted from the physical sciences, in which non-structured populations are considered. Later on it became clear that a more detailed description of social structures was required to correctly describe epidemic dynamics, and concepts such as social group, social network and social cohesion became important terms in the quantitative study of epidemics. The approximation between epidemiology and the social sciences turns obvious as their concepts are interacting more and more. To give a brief overview of this trajectory is the purpose of this article.

Chikungunya virus is a cause of encephalitis in children in bellary, India

Introduction: Chikungunya virus, a single stranded RNA Alphavirus of the family Togaviridae, is transmitted to humans by the bite of Aedes aegypti, Aedes albopictus and other mosquitoes. An epidemic starting in Reunion Islands in March 2005 spread to Southern India, affecting 1.3 million people between Oct 2005 and Oct 2006. The epidemic reached Bellary, Karnataka in southern India by Dec 2005. Methods: From Oct 2005 to Dec 2007, children admitted to the paediatric department of the Vijayanagar Institute of Medical Sciences with an acute encephalitis syndrome were prospectively studied. All children presenting to the paediatric ward were recruited if they had suspected CNS infection or acute flaccid paralysis [and] fever or history of fever in the previous 2 weeks, together with one or more of the following: meningism (neck stiffness), photophobia, severe headache meriting lumbar puncture, altered mental state, reduced consciousness, convulsions, focal neurological signs or acute flaccid paralysis. Results: 243 patients have been recruited to date. Between April and Oct 2006, 8 children had positive plasma PCR tests for Chikungunya RNA and are described in more detail. Viral RNA was also detected by PCR in the CSF of 3 of these 8. Mean age was 6 years, range 8 months to 11 years, 5 were girls. 3 children had a rash at some stage in their illness and one had conjunctivitis. Altered mental state was reported in 7, and 6 had a GCS of less than 15 at admission. One had deafness, 3 had nausea and vomiting, and 3 had meningism. 7 had seizures, amongst whom 4 had an episode of status epilepticus (seizure lasting more than 30 minutes). 3 were aphasic during their illness and 4 had extensor plantar reflexes. There were no fatalities. At discharge, 2 patients had ongoing aphasia. The remaining 4 with a reduced GCS at admission had recovered to full coma score. Sequencing information obtained from the E1 envelope gene from plasma and CSF samples confirmed that the chikungunya genomes are of the East African lineage, which appears to have caused the more severe epidemic form of illness, compared to the Asian genotype which previously circulated in India. Conclusions: Chikungunya virus causes encephalitis in children and may be found in the CSF. It can cause severe neurological disease sequelae although the extent to which these sequelae will persist is uncertain. Given frequent travel between Asia and Europe and the potential for autochtonous transmission, as has occurred in Italy, we need to be increasingly aware of global disease outbreaks. A CASE OF HYPERCALCAEMIA IN THE RETURNING

Epidemiological study ofVibrio choleraeusing variable number of tandem repeats

By conventional genetic methods, including pulse-field gel electrophoresis and multilocus sequence typing, most pathogenic, cholera toxin-positive O1 and O139 isolates of Vibrio cholerae cannot be distinguished. We evaluated relationships among 173 V. cholerae isolates collected between 1992 and 2007 from different geographic areas in India by analyzing five variable number of tandem repeat (VNTR) loci. Each VNTR locus was highly variable, with between 5 and 19 alleles. eburst analysis revealed four large groups of genetically related isolates. Two groups contained genotypes of isolates with the O139 serogroup (which emerged for the first time in epidemic form in 1992), with the other two groups containing O1 strains. In subsequent analysis, it was possible to track the spread of specific genotypes across time and space. Our data highlight the utility of the methodology as an epidemiologic tool for assessing spread of isolates in both epidemic and endemic settings.

Elevated FDG Uptake in Kaposi Sarcoma Mimicking Hodgkin's Lymphoma Relapse

Abstract: Kaposi sarcoma (KS) is a tumor caused by human herpesvirus 8, also known as KS-associated herpesvirus. Epidemiological varieties are represented by an epidemic form, strongly associated with AIDS, classic form, endemic form, and transplant-related form in association with severely immunosuppressive drug regimens, pointing to a role for immunodeficiency in the development of KS. We report the case of a woman who had preexisting immune system damage because of recurrent Hodgkin's lymphoma and presented with KS of the pelvis with high FDG uptake on PET/CT mimicking nodal relapse. Clinicians and nuclear medicine physicians should be aware that KS can present as intense FDG uptake. Moreover, our case emphasizes the importance of obtaining a biopsy.

Romanian experience in post‐event environment surveillance for West Nile virus infections

In the summer of 1996 Romania experienced a large outbreak of West Nile virus (WNV) meningoencephalitis with more than 500 clinical cases and high rates of death (up to 10%). It was the first epidemic recorded in Europe associated with urban/suburban infrastructural conditions that favoured an increase in the distribution and abundance of mosquito vectors. Careful monitoring of acute neurological human cases reported in previously affected districts, during a 10‐year period following the epidemic, revealed a gradual decrease of viral transmission and the absence of recurrent outbreaks. An additional benefit of WNV surveillance system has been the ability to pick up summer meningoencephalitis outbreaks or other causes of neurologic morbidity, like heatstroke, occurring in epidemic form during heat waves. This article provides a critical analysis of the post‐epidemic surveillance system together with a review of the intermediate‐term changes in ecological factors favouring viral transmission, by increasing interaction between mosquito vectors, avian hosts and susceptible human population.

Ecological interaction of toxigenic Vibrio cholerae in aquatic environment

Toxigenic Vibrio cholerae is the etiological agent of cholera, an acute dehydrating diarrhoea that occurs in epidemic form in many developing countries. Aquatic ecosystem is the major habitat of toxigenic V. cholerae, where it interacts with various abiotic and biotic factors to survive. To acknowledge the seasonal appearance, endemic nature and genetic deviation of V. cholerae it is essential to understand the interaction of V. cholerae with biotic and abiotic factors in aquatic ecosystem. This article summarizes the ecological interaction of toxigenic V. cholerae with different abiotic and biotic factors in aquatic ecosystem during the interepidemic period and their effect in clonal shift due to change of population structure. Suitable salinity, pH, nutrient content, temperature and the presence of aquatic macrophytes, phytoplanktons, zooplanktons, fish, mollusks and crustaceans present in the aquatic ecosystem favors the survival of toxigenic V. cholerae. Diversity, relatedness and ecological interaction of toxigenic vibrio population in different habitats can bring changes in genetic make up due to natural stresses. In aquatic ecosystem V. cholerae interact with ecofactors for its survival and fluctuation in population structure may cause the dynamics of the diseases.

Phénomènes psychogéniques collectifs et lieux de travail: Le cas particulier de l’hôpital

Mass psychogenic phenomena can affect adults within their working community in a primitive way. It appears that people working in hospitals are exceptionally affected by these phenomena even if they are daily exposed to contagious risks. On the other hand, two French examples show that a hospital is a fertile breeding ground for the development of the sick building syndrome. This syndrome, in its epidemic form and beyond the environmental factors triggering it, appears as a variant of the same collective psychogenetic phenomenon and sick building syndrome is a politically correct way to designate it. The authors present social reasons playing a role in the diffusion of these phenomena.

A community-based study of asthenopia in computer operators

There is growing body of evidence that use of computers can adversely affect the visual health. Considering the rising number of computer users in India, computer-related asthenopia might take an epidemic form. In view of that, this study was undertaken to find out the magnitude of asthenopia in computer operators and its relationship with various personal and workplace factors. To study the prevalence of asthenopia among computer operators and its association with various epidemiological factors. Community-based cross-sectional study of 419 subjects who work on computer for varying period of time. Four hundred forty computer operators working in different institutes were selected randomly. Twenty-one did not participate in the study, making the nonresponse rate 4.8%. Rest of the subjects (n = 419) were asked to fill a pre-tested questionnaire, after obtaining their verbal consent. Other relevant information was obtained by personal interview and inspection of workstation. Simple proportions and Chi-square test. Among the 419 subjects studied, 194 (46.3%) suffered from asthenopia during or after work on computer. Marginally higher proportion of asthenopia was noted in females compared to males. Occurrence of asthenopia was significantly associated with age of starting use of computer, presence of refractive error, viewing distance, level of top of the computer screen with respect to eyes, use of antiglare screen and adjustment of contrast and brightness of monitor screen. Prevalence of asthenopia was noted to be quite high among computer operators, particularly in those who started its use at an early age. Individual as well as work-related factors were found to be predictive of asthenopia.

Idiopathic Brainstem Neuronal Chromatolysis (IBNC): a novel prion protein related disorder of cattle?

BackgroundThe epidemic form of Bovine Spongiform Encephalopathy (BSE) is generally considered to have been caused by a single prion strain but at least two strain variants of cattle prion disorders have recently been recognized. An additional neurodegenerative condition, idiopathic brainstem neuronal chromatolysis and hippocampal sclerosis (IBNC), a rare neurological disease of adult cattle, was also recognised in a sub-set of cattle submitted under the BSE Orders in which lesions of BSE were absent. Between the years of 1988 and 1991 IBNC occurred in Scotland with an incidence of 7 cases per 100,000 beef suckler cows over the age of 6 years.ResultsWhen the brains of 15 IBNC cases were each tested by immunohistochemistry, all showed abnormal labelling for prion protein (PrP). Immunohistological labelling for PrP was also present in the retina of a single case available for examination. The pattern of PrP labelling in brain is distinct from that seen in other ruminant prion diseases and is absent from brains with other inflammatory conditions and from normal control brains. Brains of IBNC cattle do not reveal abnormal PrP isoforms when tested by the commercial BioRad or Idexx test kits and do not reveal PrPres when tested by Western blotting using stringent proteinase digestion methods. However, some weakly protease resistant isoforms of PrP may be detected when tissues are examined using mild proteinase digestion techniques.ConclusionThe study shows that a distinctive neurological disorder of cattle, which has some clinical similarities to BSE, is associated with abnormal PrP labelling in brain but the pathology and biochemistry of IBNC are distinct from BSE. The study is important either because it raises the possibility of a significant increase in the scope of prion disease or because it demonstrates that widespread and consistent PrP alterations may not be confined to prion diseases. Further studies, including transmission experiments, are needed to establish whether IBNC is a condition in which prion protein is abnormally regulated or it is yet a further example of an infectious cattle prion disease.

Bioboard

AUSTRALIA — Australian Scientist Awarded $1M for Gene Therapy Research. AUSTRALIA — $900,000 Multiphoton Microscope Unveiled at Sydney's Centenary Institute. AUSTRALIA — Australian Stem Cell Scientist on Target to Prevent Age-related Loss of Brain Function. CHINA — Chinese Scientists Complete Successful Greenhouse Breeding of a Medicinal Herb. CHINA — China Aoxing Pharmaceutical Designated as Key Manufacturer of Cancer Pain Drug, Tilidine. CHINA — Chinese Neuropsychologist Makes Novel Progress in Studies of Schizophrenia. JAPAN — Vetter Receives Japanese Certificates of Accreditation of Foreign Manufacturer. INDIA — Heart Problems to Take Epidemic Form in India. INDIA — Scientists Discover the Most Important Candidate Genes for Pancreatic Stone Formation. INDIA — India and Canada to Collaborate on Pharma Opportunities. INDIA — Tata Drug Development Center Opens in Bangalore. NEW ZEALAND — A Squid Gel Commands Global Attention. SINGAPORE — Singapore's National Cancer Center Launches Its First Satellite Clinic. SINGAPORE — Lien Foundation to Develop Electronic Healthcare System. TAIWAN — STUT Study Reveals Mushroom Good for Ovarian Cysts.

Rapid Detection of Oculopathogenic Adenovirus in Conjunctivitis

Ocular adenovirus (Ad) infections occur throughout the world in both sporadic and epidemic forms. Accurate laboratory diagnosis of Ad in conjunctival samples is always valuable. The present study was carried out to explore the presence of Ad as a causative agent in clinically suspected viral conjunctivitis and to compare the performance of conventional virus isolation on cell cultures, direct detection of Ad antigens in conjunctival cells by a direct fluorescence assay, Ad DNA detection by polymerase chain reaction (PCR), and specific IgM measurement by ELISA. Samples included scrapes from conjunctiva. Scrapes were subjected to study by direct immunofluorescence stain, culture on the Hep-2 cell line, and PCR for Ad detection. Blood samples were also taken and subjected to study for specific anti-Ad IgM determination. The culture for Ad was positive in 77.8%, direct antigen detection by fluorescent stain was positive in 72.2%, PCR was positive in 83.3%, and serology was positive in 88.9% of patients. Both determination of antibody IgM and PCR correctly identified a larger group of patients compared to cell culture. The most sensitive and specific method for diagnosis of Ad compared to culture was PCR (100%), followed by IgM detection (92.9%) then direct antigen detection by fluorescent stain (85.8%). From this study, we conclude that Ad is a common pathogen in sporadic cases of conjunctivitis. Screening of adenoviral conjunctivitis is possible by using specific IgM due to its high sensitivity. A confirmatory test can be done by PCR for diagnosis of Ad, as it is a rapid, specific, and accurate method.

The Immune Response in Patients with SARS: differential gene expression profiling.

AbstractSevere acute respiratory syndrome (SARS) emerged in 2003, as a new epidemic form of life-threatening infection. As of 26th September 2003, there were 8422 cases of SARS from 29 countries with 908 deaths (WHO). However, the pathogenesis of SARS is poorly understood. To understand the host response to this pathogen, we profiled the gene expression patterns of peripheral blood mononuclear cells (PBMC) from SARS patients compared to healthy controls using one of the latest techniques, high density oligonucleotide expression probe array (HG-Focus array, Gene Chip, Affymetrix, Santa Clara, CA). High-density oligonucleotide microarray is a promising approach for high throughput analysis. It has been extensivelyused in many areas of biomedical research for different purposes. Thus we could compare the expression levels of thousands of genes which are differentially expressed in SARS patients over healthy controls. Among the most prominent findings, we observed 2 to 200-fold increased expression of transcripts of various genes. This enabled us to classify and cluster genes by functional families as well as to understand known genes in signalingpathways.

Echovirus 15 and autumn meningitis outbreak among children, Patras, Greece, 2005

Background Enteroviruses are the most common cause of aseptic meningitis, presenting in epidemic or endemic form. Objectives To determine the causative agent of an aseptic meningitis outbreak in autumn, 2005 in Patras, Greece. Study design Cerebrospinal fluid (CSF) samples taken during May 2005–February 2006 from children admitted to the Children Hospital of Patras with signs of aseptic meningitis were tested for the presence of enteroviral RNA. Typing was performed by nucleotide analysis. Results Enteroviruses were detected in 11 (57.9%) of 19 tested CSF samples. In a 12-day period (27 October–7 November 2005) five aseptic meningitis cases were observed. Echovirus 15 was detected in all five cases, and differed from the prototype strain by 27.6%. Enteroviruses before and after this cluster of cases were of different serotypes (Echovirus 9, Echovirus 6). All patients with Echovirus 15 infection were male with a mean age of 7.7 years (2 months–13 years), all recovered successfully. Conclusions This is the first report of a cluster of aseptic meningitis cases caused by Echovirus 15. The causative agent was a new variant of Echovirus 15.

Evidence of COX-1 and COX-2 expression in Kaposi’s sarcoma tissues

Cyclooxygenases (COXs) are enzymes catalysing prostaglandin synthesis and are implicated in the carcinogenesis of some cancer types. In addition, an important role of these enzymes in herpesvirus infections was demonstrated and it has recently been proposed that COX-2 may participate in herpesvirus-induced neoplasia such as Kaposi’s sarcoma (KS). To date no immunohistochemical study has been performed to determine the identification of COX-1 and COX-2 in KS. We have investigated 35 cases of classic KS and 27 cases of epidemic KS form in order to study the distribution and localisation of COXs. We have examined by immunohistochemistry the expression of COX-1 and COX-2 in classic and epidemic forms of KS also in relationship to the characteristic morphological phases (patch, plaque and nodular stage) of KS and cell localisation by double immunostaining. Moreover, we have obtained COX-1 and COX-2 expression by Western blot analysis. Our results establish that (a) COX-1 and COX-2 are overexpressed significantly in classic and epidemic KS compared with control skin tissues ( P < 0.01 and P > 0.03, respectively, for COX-1; P < 0.01 and P > 0.03, respectively, for COX-2); (b) the extent and intensity staining for both COXs were higher in classic than in epidemic form of KS. Our data support the hypothesis that both COXs may be involved in the pathogenesis of KS.

Epidemiological Investigation of the Prevalence and Features of Postweaning Multisystemic Wasting Syndrome in Japan

To investigate the prevalence and features of postweaning multisystemic wasting syndrome (PMWS) in Japan, an epidemiological study was conducted in 692 weaned pigs with various clinical signs, commonly including wasting or weight loss, collected from 129 swine farms between 2000 and 2003. The presence of PMWS was diagnosed by the detection of characteristic histological lesions and moderate to large amounts of porcine circovirus type 2 (PCV2) antigen within the lesions in multiple lymphoid tissues. Postweaning multisystemic wasting syndrome was positive in 23.4% of pigs (162/692) over the course of the study, and occurred in 50.4% of the farms (65/129). Mortality in 30-120-day-old pigs in the farms positive for PMWS varied from 0.1 to 32.0%. No significant difference in mortality was seen between PMWS-positive and -negative farms (P = 0.1). However, mortality was significantly higher in the PMWS-positive farms where PMWS was diagnosed in more than 50% of the pigs examined compared to farms negative for PMWS (P = 0.02). These findings indicate that PMWS has spread widely in Japan. Moreover it may exist in variable forms in swine farms, including an epidemic form or a subtle endemic or sporadic form. A case-control study suggested that risk factors for the occurrence of PMWS include porcine reproductive and respiratory syndrome (PRRS) pneumonias and Mycoplasma hyorhinis infection.