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Hemorrhagic Fever (hemorrhagic + fever)
Kinds of Hemorrhagic Fever Selected AbstractsImplications of previous subclinical dengue infection but not virus load in dengue hemorrhagic feverFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2006Wen-Ting Yeh Abstract In a study comparing the virus load and immune reaction between patients with primary and secondary dengue-2 (DEN-2) infections in a hospital-based analysis, we found that 40.7% (55/135) of the 135 patients had secondary DEN-2 infection following a DEN-2 outbreak in southern Taiwan. Most of the secondary infections had subclinical primary dengue infections (78.2%; 43/55). Patients with secondary DEN-2 infections had lower platelet counts, and blood interferon-, and virus load, but significantly higher interleukin-10 (P=0.030) and anti-DEN-1 neutralization titers (P=0.013) than those with primary infection. Patients with secondary DEN-2 infection also had a higher rate of dengue hemorrhagic fever (DHF) (61.7% vs. 36.3%). A previous subclinical dengue infection is involved in the secondary DEN-2 infection associated with altered immune reaction and higher DHF rate, but lower blood virus load. [source] Cytokine cascade in dengue hemorrhagic fever: implications for pathogenesisFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2000U.C. Chaturvedi Abstract Dengue virus produces a mild acute febrile illness, dengue fever (DF) and a severe illness, dengue hemorrhagic fever (DHF). The characteristic feature of DHF is increased capillary permeability leading to extensive plasma leakage in serous cavities resulting in shock. The pathogenesis of DHF is not fully understood. This paper presents a cascade of cytokines, that in our view, may lead to DHF. The main feature is the early generation of a unique cytokine, human cytotoxic factor (hCF) that initiates a series of events leading to a shift from Th1-type response in mild illness to a Th2-type response resulting in severe DHF. The shift from Th1 to Th2 is regulated by the relative levels of interferon-gamma and interleukin (IL)-10 and between IL-12 and transforming growth factor-,, which showed an inverse relationship in patients with DF. [source] Cutaneous manifestations of dengue viral infection in Punjab (north India)INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2007Emy Aby Thomas MBBS Background, Dengue infection is emerging as a public health problem in India. Despite numerous studies, there is a paucity of literature regarding the cutaneous manifestations of dengue. This study was performed to investigate the prevalence and type of cutaneous manifestations in dengue viral infection. Methods, Two hundred and fifty-six patients with febrile illness, admitted to the Christian Medical College and Hospital, Ludhiana, India, were studied. On the basis of the clinical criteria and laboratory tests, 124 patients were diagnosed with dengue viral infection, and these patients were investigated in detail. Serologic tests were attempted in only 84 patients, and all of these samples tested positive for anti-dengue immunoglobulin M (IgM) antibodies. Results, Of the 124 patients with dengue infection, 41 (23.1%) were classified with dengue fever (DF) and 83 (66.9%) with dengue hemorrhagic fever (DHF), four (3.2%) of whom had dengue shock syndrome (DSS). Cutaneous involvement was seen in 46.8% of patients, the most common symptom being maculopapular/morbilliform eruption (48.3%), followed by ecchymotic (27.6%), petechial (13.8%), and macular/scarlatiniform (10.3%) eruption. Maculopapular eruption was observed more in DF, whereas petechiae, ecchymosis, and mucosal involvement were seen more in DHF; 72.4% of patients with cutaneous manifestations were asymptomatic, and 27.6% had pruritus. Involvement was generalized in 48.3% of patients, with the limbs and trunk involved in 32.8% and 18.9% of patients, respectively. Mucosal involvement was seen in 29.8% of patients, with conjunctival involvement being the most common (20.9%), followed by the lips (4.8%), palate (2.4%), and tongue (1.6%). Conclusions, This study describes the variety of cutaneous features associated with dengue viral infection which may evolve during the course of the disease. As a significant proportion of patients showed cutaneous features, these manifestations, together with simple laboratory tests, will be helpful in the early diagnosis of dengue viral infection. [source] Early abdominal sonographic findings in patients with dengue feverJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2004Keng-Liang Wu MD Abstract Purpose This study was conducted to evaluate the early sonographic findings in dengue hemorrhagic fever. Methods From July 2002 to September 2002, 86 patients were referred to our center with suspected dengue fever during an outbreak of the disease in Taiwan. All the patients underwent immediate abdominal sonography when they arrived at our emergency room. The diagnosis of dengue fever was subsequently confirmed by serology in 65 patients. Results All our patients had type 2 dengue fever, as confirmed by serologic tests. The sonographic features included a thickened gallbladder wall in 38 patients (59%), ascites in 24 patients (37%), splenomegaly in 22 patients (34%), and pleural effusion in 21 patients (32%); pleural effusion was either right-sided or bilateral. Conclusions Abdominal sonography can be used as a first-line imaging modality in patients with suspected dengue fever to detect early signs suggestive of the disease prior to obtaining serologic confirmation test results, especially in a dengue fever epidemic area. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:386,388, 2004 [source] HFRS causing hantaviruses do not induce apoptosis in confluent Vero E6 and A-549 cells,JOURNAL OF MEDICAL VIROLOGY, Issue 2 2005Jonas Hardestam Abstract Hantaviruses are known to cause little or no cytopathic effect in vitro, but have been suggested to cause apoptosis. To determine whether different hantaviruses would induce apoptosis to varying degrees, confluent Vero E6 cells were infected with the hemorrhagic fever with renal syndrome (HFRS) causing viruses Hantaan, Dobrava, Saaremaa, and Puumala. However, no difference was found in the percentage of adherent cells, or of cells with condensed nuclei, between non-infected and virus-infected cells at 3, 6, 9, or 12 days after infection. Furthermore, no differences in the percentage of cells with inter-nucleosomal cleavage of DNA between uninfected and Hantaan infected cells could be detected using the TUNEL assay. Possibly, slightly more apoptotic cells, but never more than 5%, were detected after Hantaan infection of non-confluent cells as compared to the negative control. Earlier reported results that Tula hantavirus induces significant apoptosis on Vero E6 cells were also verified, suggesting that non-pathogenic hantaviruses might differ from HFRS-causing strains regarding induction of apoptosis. In conclusion, the results indicated that the HFRS-causing hantaviruses might induce a very low level of apoptosis in dividing cells, but not at all in confluent cells. J. Med. Virol. 76:234,240, 2005. © 2005 Wiley-Liss, Inc. [source] Genetic characterization of the M RNA segment of a Balkan Crimean-Congo hemorrhagic fever virus strain,JOURNAL OF MEDICAL VIROLOGY, Issue 3 2005Anna Papa Abstract Crimean-Congo hemorrhagic fever (CCHF) virus causes one of the most severe diseases in humans, with a mortality rate of up to 30%. It is transmitted to humans by the bite of hard ticks or by contact with blood or tissues from human patients or infected livestock. Balkan Peninsula is an endemic region of the disease, and sporadic cases or even outbreaks are observed every year. The M RNA segment encodes for the glycoprotein precursor of two surface glycoproteins Gn and Gc. Up to now complete M RNA CCHF virus sequences have been published from strains isolated in Nigeria, China, Pakistan, Tajikistan, and Russia. In the present study, the genetic characterization of the complete nucleotide sequence of the M RNA segment of a Balkan CCHF virus strain, Kosovo/9553/2001, isolated in summer of 2001 from a human fatal case in Kosovo is reported. This is the first published complete M nucleotide sequence of a CCHF virus strain isolated in Balkans. It was found that the Balkan strain is similar to the Russian strain, both strains differing from all other completely sequenced CCHF virus strains by approximately 22% at the nucleotide level forming an independent clade in the phylogenetic tree. J. Med. Virol. 75:466,469, 2005. © 2005 Wiley-Liss, Inc. [source] Characteristics of puumala and Dobrava infections in Croatia,JOURNAL OF MEDICAL VIROLOGY, Issue 4 2002A. Markoti Abstract In this study, two different hantaviruses, Puumala virus (PUUV) and Dobrava virus (DOBV), were demonstrated for the first time to coexist and cause hemorrhagic fever with renal syndrome (HFRS) in Croatia. Phylogenetic analysis showed some differences among the nucleotide sequences of PUUV originating from Dinara mountain, which was more closely related to Austrian PUUV than other Croatian PUUV from Mala Kapela mountain. More consistency was found among the Croatian DOBV. HFRS was verified in 85 of 201 suspected cases recorded in 1995 during the largest HFRS outbreak in Croatia. Most of these cases were soldiers. With the exception of the coastal region and islands, all of Croatia was found to be an area endemic for HFRS. A statistically significantly higher proportion of DOBV-infected patients had acute renal failure, visual disturbance, severe thrombocytopenia, and elevated levels of nonsegmented leukocytes, creatine, and total bilirubin. The prevalence of gastrointestinal and electrocardiography disorders also was greater in DOBV-infected patients. Interestingly, significantly more PUUV-infected patients had elevated systolic blood pressure on admission to the hospital. Further prospective studies are necessary to shed more light on differences in HFRS severity associated with PUU and DOB viruses. J. Med. Virol. 66:542,551, 2002. © 2002 Wiley-Liss, Inc. [source] Characterization of tick-borne encephalitis virus from latvia: Evidence for co-circulation of three distinct subtypesJOURNAL OF MEDICAL VIROLOGY, Issue 4 2001Åke Lundkvist Abstract Viruses of the tick-borne encephalitis (TBE) antigenic complex within the family Flaviviridae cause a variety of diseases, including uncomplicated febrile illness, meningoencephalitis, and hemorrhagic fever. Different domesticated animals or wildlife species often act as reservoir hosts and ixodid ticks serve as vectors. Although TBE is a serious problem in Latvia, the knowledge concerning TBE virus (TBEV) strains circulating in the country is most limited. Only two strains (Latvia-1-96 isolated from a TBE patient, and RK1424 originating from an Ixodes persulcatus tick), which belonged to the Siberian and the Far Eastern subtypes of TBEV, respectively, have previously been characterized. In the present study, we concentrated on the western and central regions of Latvia, with predominantly Ixodes ricinus ticks. Five virus strains were isolated from serum samples of patients with clinical symptoms of an acute TBE infection. Nucleotide sequences encoding the envelope (E) protein of TBEV, which were recovered from the five TBEV isolates, showed the highest level of identity to the corresponding sequences of the prototype strain Neudoerfl and other European strains of the Western TBEV subtype characterized previously. Accordingly, phylogenetic analysis placed the new Latvian isolates within the Western genetic lineage of TBEV. Taken together with earlier observations, the results proved that all three TBEV subtypes are co-circulating in Latvia and indicated that the genetic diversity of TBEV within certain geographical areas is much more complex than previously believed. J. Med. Virol. 65:730,735, 2001. © 2001 Wiley-Liss, Inc. [source] Larvicidal and oviposition-altering activity of monoterpenoids, trans -anithole and rosemary oil to the yellow fever mosquito Aedes aegypti (Diptera: Culicidae),PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2009Ranil Waliwitiya Abstract BACKGROUND:Aedes aegypti L. is the major vector of dengue fever and dengue hemorrhagic fever. In an effort to find effective tools for control programs to reduce mosquito populations, the authors assessed the acute toxicities of 14 monoterpenoids, trans -anithole and the essential oil of rosemary against different larval stages of Ae. aegypti. The potential for piperonyl butoxide (PBO) to act as a synergist for these compounds to increase larvicidal activity was also examined, and the oviposition response of gravid Ae. aegypti females to substrates containing these compounds was evaluated in behavioral bioassays. RESULTS: Pulegone, thymol, eugenol, trans -anithole, rosemary oil and citronellal showed high larvicidal activity against all larval stages of Ae. aegypti (LC50 values 10.3,40.8 mg L,1). The addition of PBO significantly increased the larvicidal activity of all test compounds (3,250-fold). Eugenol, citronellal, thymol, pulegone, rosemary oil and cymene showed oviposition deterrent and/or repellent activities, while the presence of borneol, camphor and ,-pinene increased the number of eggs laid in test containers. CONCLUSIONS: This study quantified the lethal and sublethal effects of several phytochemical compounds against all larval stages of Aedes aegypti, providing information that ultimately may have potential in mosquito control programs through acute toxicity and/or the ability to alter reproductive behaviors. Copyright © 2008 Society of Chemical Industry [source] | ||||||||||