云南省登革热流行病学调查分析

本对以往云南省登革热病原学、血清学和蚊媒调查资料进行了整理分析。从采自河口市的２９批雌性白纹伊蚊（Ａｅｄｅｓ ａｌｂｏｐｉｃｔｕｓ）中分离到登革４型病毒１株。从采自西双版纳地区（景洪、勐腊、勐海）的７２批２７２６只雌性白纹伊蚊中分离到登革病毒４株,其中４株３株,３型１株。批阳性率５．６％,现场感染比为１：６８２。本省２４个省、市人血清中登革ＣＦ抗体阳性率为１０．９１％（１８５／１６９６）,１５个     

登革热的腹部超声表现

登革热（DF）是由登革热病毒引起，经伊蚊传播的急性传染病。广东省5月-11月是登革热发病的高峰期，近年有扩大流行的趋势。关于登革热的腹部超声表现目前国内较少有报道。本文对54例登革热患者进行常规的腹部超声检查，现报道如下。     

Evaluation of Platelets as Predictive Parameters in Dengue Fever

Dengue is an arboviral disease and occurs in tropical countries where over 2.5 billion people are at risk of infection. Each year an estimated 100 million cases of dengue fever (DF) occur and between 2.5 and 5 lakh cases of dengue hemorrhagic fever (DHF) are reported to WHO. Severe thrombocytopenia and increased vascular permeability are two major characteristics of DHF. A study was conducted to note the relationship between the platelet counts and severity of the disease in pediatric cases of dengue fever. Platelet counts were found to be predictive as well as recovery parameter of DF/DHF/DSS.     

Unfurling the Rationale Use of Platelet Transfusion in Dengue Fever

Dengue fever and dengue haemorrhagic fever have emerged as a global public health problem in recent decades. The practice of platelet transfusion has been adapted into the standard clinical practice in management of hospitalized dengue patients. The exact indications and situations in which platelet have to be transfused may vary greatly. Blood components especially platelet concentrates due to their short shelf life are frequently in limited supply. Hence, appropriate use of blood is required to ensure the availability of blood for patients in whom it is really indicated, as well as to avoid unnecessary exposure of the patients to the risk of transfusion reactions and transmission of blood borne infection. The present study was conducted to evaluate the appropriateness of platelet transfusion done in dengue patients with thrombocytopenia. The present study was conducted on 343 serologically confirmed dengue patients admitted at JSS University Hospital between 1st January and 30th August 2009. Clinical data, platelet count and platelet requirements were analyzed. Among the 343 serologically confirmed cases, the prevalence of thrombocytopenia (platelet count < 100,000/cumm) was 64.72% (222 patients) and bleeding manifestations were recorded in 6.12% (21 patients). 71 (20.7%) patients of dengue cases received platelet transfusion. Among them 34 (47.89%) patients had a platelet count <20,000/cumm, 28 patients (39.44%) had platelet counts in the range of 21–40,000/cumm while the remaining 9 (12.67%) patients had platelet count between 41–100,000/cumm. Out of 37 patients with a platelet count >20,000/cumm 11 patients had haemorrhagic manifestations such as petechiae, gum bleeding, epistaxis etc., which necessitates the use of platelet transfusion. However, the remaining 26 patients with platelet count >20,000/cumm and with no haemorrhagic manifestations received inappropriate platelet transfusion. Transfusion of 36.62% of platelet concentrate was inappropriate. The study emphasizes the need for development of specific guidelines for transfusion of blood components, constant interaction and co-ordination amongst clinicians and transfusion centre for implementation of these guidelines and a regular medical audit to review the optimal utilization of blood components.     

Severe Thrombotic Events Associated with Dengue Fever,Brazil

Dengue fever has been a major problem in hospital settings in Brazil for the past 15 years. The main concern has been the severe forms, i.e., dengue hemorrhagic fever and dengue shock syndrome. Hemorrhagic events of different degrees have also been a major concern. We report five cases of large vein thrombotic events associated with the acute phase of dengue fever, including a previously non-reported case of mesenteric vein thrombosis. Complications such as these could have been overlooked in the diagnosis of dengue fever, given that the major concern is the hemorrhagic event.Dengue fever frequently affects Brazil, where thousands of cases have been diagnosed annually and all four dengue virus serotypes (DENV-1 through DENV-4) have been reported, sometimes concurrently in the same region.^1,2 Hemorrhagic events of different degrees have often been described in dengue, but thrombotic events have not been extensively reported, despite the wide range of increased procoagulant activity during illness.^1,3–8 During a recent outbreak, several cases of thrombotic events affected large veins in dengue fever patients. We report cases of unusual and overlooked complication of dengue fever.From January 2011 through March 2011 during a local outbreak of dengue fever caused by DENV-1 and DENV-2 according to local health officials, five patients were given diagnoses by imaging techniques (pulmonary computed tomography angiography, cholangio-magnetic resonance imaging, and Doppler ultrasound of lower extremities) as having large vessel thrombosis. These patients were part of 92 serologically confirmed (by immunochromatographic strip test or IgM antigen-capture enzyme-linked immunosorbent assay) patients with dengue (60% women and 40% men, median age = 39 years, age range = 10–99 years) admitted to Monte Sinai Hospital (200 beds) in Juiz de Fora, (population = 500,000), Minas Gerais, Brazil. This study was approved by the Ethical Committee of Monte Sinai Hospital.Twenty-three patients (25%) were classified as having dengue shock syndrome or dengue hemorrhagic fever and 4 deaths were recorded (case-fatality rate = 4.3%). These thrombotic patients represented 5.4% of all dengue inpatients. All thrombotic events were identified within the first five days of illness, and all patients had symptoms compatible with the reported thrombotic event at hospital admission. No thrombotic events were identified among the remaining patients during hospitalization, and none of the patients them received drugs for thrombosis prophylaxis, which is contraindicated in dengue.The demographic and clinical characteristics of the five patients are summarized in Figure 1), which was associated with jaundice and severe sepsis by Escherichia coli demonstrated by blood culture. Known risk factors for thrombotic events such as smoking, use of oral contraceptives, and being overweight were absent in all patients and none had had any similar diagnosis or symptoms.Open in a separate windowFigure 1.T1-weighted cholangio-magnetic resonance image with contrast of dengue patient 5 showing the superior mesenteric vein (SMV) with a large thrombus (arrow) occupying the vein lumen. SMA = superior mesenteric artery; IVC = inferior vena cava; Ao = aorta.

Table 1

Demographic, clinical, and laboratory characteristics of five dengue fever patients with thrombotic events, Brazil^*

Hemoglobinopathies in China Mainland

Separation of the globin polypeptide chains of hemoglobin using electrophoresis on polyacrylamide gels in acid, urea, and Triton X-100 was initially described by Rovera et al (1). We have utilized this method for human (2) and murine systems (3), and have shown that the technique will separate embryonic, fetal, and adult globin chains from both species (4, 5).     

Dengue Hemorrhagic Fever: A State-of-the-Art Review Focused in Pulmonary Involvement

Dengue fever is an arboviral disease transmitted to humans through the bites of infected female Aedes mosquitoes. Dengue virus is a member of the Flaviviridae family, and human infection can be caused by any of the four antigenically distinct serotypes (DENV 1–4). The infection has become recognized as the most important and prevalent arboviral disease in humans, endemic in almost 100 countries worldwide. Nearly 3 billion people live in areas with transmission risk. Autochthonous transmission of the virus in previously disease-free areas, increased incidence in endemic areas, and epidemic resurgence in controlled regions could increase the risk of contracting more severe forms of the disease, such as dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS). Symptomatic dengue virus infection can present with a wide range of clinical manifestations, from mild fever to life-threatening DSS. Thoracic complications may manifest as pleural effusion, pneumonitis, non-cardiogenic pulmonary edema, and hemorrhage/hemoptysis. No vaccine is currently available and no specific treatment for dengue fever exists, but prevention and prompt management of complications in patients with DHF can help reduce mortality. This review describes the main clinical, pathological, and imaging findings of thoracic involvement in DHF.     

Prevalence and Clinical Differentiation of Dengue Fever in Children in Northern India

Study  Although an increasing trend in outbreaks of dengue infection is seen in the northern Indian plains, the importance of dengue infection as a cause of acute undifferentiated febrile illness (AUFI) round the year is not known and the validity of clinical signs and simple laboratory parameters in differentiating dengue from other causes of AUFI has been sparsely reported. Objectives  To study the prevalence of dengue infection as a cause of AUFI seen round the year and validity of clinical and simple laboratory features for its diagnosis. Methods  Consecutive children between 6 months and 12 years of age presenting to outpatients on 3 predecided weekdays with complaints of fever of 15 days or less duration and having no localizing signs of infection were enrolled over a 1-year period. Blood counts, liver function tests and ELISA test for dengue IgM were performed besides other investigations. Those testing positive for IgM were considered “probable dengue” (PD) while those with negative IgM tested after 5 days of illness were considered “nondengue” (ND). Clinico-laboratory features were compared between PD and ND. A randomly selected subsample of IgM +ves was tested for dengue genome by real time PCR assay. Results  Of 298 children enrolled over 1 year, 56 (18.8%) tested positive for dengue IgM and 132 were ND. Comparing PD and ND, age, duration of illness at presentation, rash, bleeding manifestations, vomiting, platelet count, liver transaminases, serum proteins, albumen and bilirubin were significant features on univariate analysis. On logistic regression younger age, rash and higher serum alanine transaminase (sALT) levels were the only significant independent predictors for PD. Taking cutoff of age as 60 months or less and sALT > 40 units, one or more of these features were seen in 50/56 PD cases (sensitivity 89.3%). All of these were present in only 1 of 132 ND cases (specificity 99.2%). Randomly selected 44 of the 56 IgM +ve patients were subjected to PCR assay, of which 15 were positive. Conclusions  Dengue transmission occurs round the year in this region. The cause of AUFI was definitely dengue in 15/298, i.e., 5% cases and likely to be dengue in another 13.8% cases. In children presenting to outpatients here with AUFI, young age, rash, and raised sALT are significant independent pointers to dengue. A combination of clinical and laboratory features including liver enzymes could be used to achieve high sensitivity and specificity. These results should be validated in a separate data set.     

Case Report: Fatal Staphylococcal Infection following Classic Dengue Fever

Dengue represents an important public health issue in many tropical areas, leading to high morbidity and the employment of substantial health resources. Even though the number of fatalities related to dengue is unknown, several reports warn about the potential occurrence of severe infections and even death. The clinical spectrum of dengue is highly variable, ranging from a mild flu-like syndrome to severe disease, with shock and hemorrhage. The occurrence of bacterial superinfection, or coinfection, in patients with dengue has been noted by some authors, but the available information comes from anecdotic reports. In this study, we show the clinical and anatomopathological data of a patient infected with dengue, who subsequently died of acute multi-organic failure related to Staphylococcus aureus infection. The autopsy revealed a severe disseminated staphylococcal disease and confirmed dengue infection.     

Occurrence and Correlates of Symptom Persistence Following Acute Dengue Fever in Peru

Dengue virus (DENV) infection causes an acute febrile illness generally considered to result in either complete recovery or death. Some reviews describe persistent symptoms after the febrile phase, although empirical data supporting this phenomenon is scarce. We evaluated symptom persistence in acute febrile DENV-infected and DENV-negative (controls) individuals from Peru. Self-reported solicited symptoms were evaluated at an acute and a follow-up visit, occurring 10–60 days after symptom onset. Rate of persistence of at least one symptom was 7.7% and 10.5% for DENV infected and control subjects, respectively (P < 0.01). The DENV-infected individuals had lower rates of persistent respiratory symptoms, gastrointestinal symptoms, headache, and fatigue, but higher rates of persistent rash compared with controls. Older age and female gender were positively associated with symptom persistence. As dengue cases continue to increase annually, even a relatively low frequency of persistent symptoms may represent a considerable worldwide morbidity burden.     

Discovery and Characterization of Potential Prognostic Biomarkers for Dengue Hemorrhagic Fever

Half a million patients are hospitalized with severe dengue every year, many of whom would die without timely, appropriate clinical intervention. The majority of dengue cases are uncomplicated; however, 2–5% progress to severe dengue. Severe dengue cases have been reported with increasing frequency over the last 30 years. To discover biomarkers for severe dengue, we used surface-enhanced laser desorption/ionization time-of-flight mass spectrometry to analyze dengue virus positive serum samples from the acute phase of infection. Using this method, 16 proteins were identified as candidate biomarkers for severe dengue. From these 16 biomarkers, three candidates were selected for confirmation by enzyme-linked immunosorbent assay and Western blot: vitronectin (Vtn, 55.1 kDa), hemopexin (Hx, 52.4 kDa), and serotransferrin (Tf, 79.2 kDa). Vitronectin, Hx, and Tf best differentiated between dengue and severe dengue.     

Dengue Hemorrhagic Fever in a Japanese Traveler with Pre-existing Japanese Encephalitis Virus Antibody

An adult Japanese man who had just returned from Thailand developed dengue hemorrhagic fever (DHF). A primary infection of dengue virus (DENV) was confirmed, specifically DENV serotype 2 (DENV-2), on the basis of the detection of the virus genome, a significant increase in the neutralizing antibody and the isolation of DENV-2. DHF is often observed following a secondary infection from another serotype of dengue virus, particularly in children, but this case was a primary infection of DENV. Japan is a non-endemic country for dengue disease. In fact, only Japanese encephalitis (JE) is known to be a member of the endemic flavivirus family. In this study, IgG antibody against Japanese encephalitis virus (JEV) was detected. JEV belongs to the family of dengue virus and prevails in Japan, particularly Kyushu. Among many risk factors for the occurrence of DHF, a plausible candidate could be a cross-reactive antibody-dependent enhancement (ADE) mechanism caused by JEV antibody. This indicates that most Japanese travelers who living in dengue non-endemic areas, particularly Kyushu, should be aware of the occurrence of DHF.     

Regional Differences in the Growing Incidence of Dengue Fever in Vietnam Explained by Weather Variability

Dengue fever is a major health problem in Vietnam, but its incidence differs from province to province. To understand this at the local level, we assessed the effect of four weather components (humidity, rainfall, temperature and sunshine) on the number of dengue cases in nine provinces of Vietnam. Monthly data from 1999 to 2009 were analysed by time-series regression using negative binomial models. A test for heterogeneity was applied to assess the weather-dengue association in the provinces. Those associations were significantly heterogeneous (for temperature, humidity, and sunshine: P < 0.001 heterogeneity test; for rainfall: P = 0.018 heterogeneity test). This confirms that weather components strongly affect dengue transmission at a lag time of 0 to 3 months, with considerable variation in their influence among different areas in Vietnam. This finding may promote the strategic prevention of dengue disease by suggesting specific plans at the local level, rather than a nationally unified approach.