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Gustavo Kourí

Publications and source records attributed to Gustavo Kourí.

14 recordsLinked to original sources
PubMed2006

Ethnicity and difference in dengue virus-specific memory T cell responses in Cuban individuals.

The different risk factors associated with dengue hemorrhagic fever pathogenesis needs yet additional clarification. The exceptional epidemiological circumstances in Cuba allow their evaluation in a well-defined situation. In the present study the memory T cell response of 80 Cuban donors previously infected with dengue-1 and dengue-2 during the 1977 and 1981 epidemics, and belonging to different ethnic groups, was examined. White people showed, in contrast to black people, stronger and remarkably cross-reactive dengue virus-specific memory CD4(+) T lymphocyte proliferation and interferon-gamma release. The observed variation in T cell response according to ethnicity could be related to the immunopathogenesis of dengue hemorrhagic fever, and may partially explain the epidemiological evidence that black individuals are at lower risk for the most severe dengue clinical course compared with white individuals.

Adult↗
PubMed2006

[Dengue and dengue hemorrhagic fever: research priorities].

Dengue is one of the most important infectious diseases in tropical and subtropical countries. At present, the only strategy available to reduce the incidence of dengue is vector control. The World Health Organization and the Pan American Health Organization have called on all nations to take the needed steps to help diminish the burden of this disease and its medical and socioeconomic impact. It is hoped that it will be possible to reverse the increase in dengue and help control its spread through a coordinated, effective international response, along with epidemiological, clinical, and virological research that brings together the most advanced methods and techniques. This piece summarizes the most up-to-date information on dengue, analyzes current epidemiologic trends in the Region of the Americas, discusses the main global and Western Hemisphere initiatives to control the disease, and presents the main areas of research that should be developed in the immediate future.

Adult↗
PubMed2006

West Nile Virus infection in humans and horses, Cuba.

A surveillance system to detect West Nile virus (WNV) was established in Cuba in 2002. WNV infection was confirmed by serologic assays in 4 asymptomatic horses and 3 humans with encephalitis in 2003 and 2004. These results are the first reported evidence of WNV activity in Cuba.

Animals↗
PubMed2005

Classical dengue hemorrhagic fever resulting from two dengue infections spaced 20 years or more apart: Havana, Dengue 3 epidemic, 2001-2002.

OBJECTIVE: To report the clinical, laboratory and sonographic findings in 76 adult cases of dengue hemorrhagic fever (DHF). PATIENTS AND METHODS: A dengue 3 epidemic occurred in Havana City from June 2001 to March 2002. 12,889 cases were reported, with 81 DHF cases. From this, 76 serologically confirmed cases were studied descriptively. RESULTS: Bronchial asthma and white race were important risk factors for the severe form of the disease. Fever (100%), headache (92.1%), myalgia (76.3%), arthralgia (73.7%) and retro-orbital pain (57.7%) were the most frequent general symptoms. Vomiting and abdominal pain were observed in 59.2% and 48.6% of cases, respectively. The most common bleeding site was the vagina (64%), followed by the skin (55.2%). Eighteen patients (23.6%) had shock syndrome. Laboratory findings included thrombocytopenia (100%), hemoconcentration (93.4%), an increase in liver enzymes (82.8%), and leukopenia (71%). Ultrasound detected thickening of the gallbladder wall in 35.1%, pleural effusion in 20.3%, and splenomegaly in 12.9% of cases. CONCLUSION: These findings contribute to a better understanding of the clinical aspects of DHF in adult patients due to the dengue 3 virus.

Abdominal Pain↗
PubMed2004

Dengue diagnosis, advances and challenges.

Dengue diagnosis was one of the topics discussed at the symposium 'The Global Threat of Dengue - Desperately Seeking Solutions' organized during the 10th International Congress of Infectious Diseases held in Singapore in 2002. In this paper, a review is presented focusing on the main advances, problems and challenges of dengue diagnosis.IgM capture ELISA, virus isolation in mosquito cell lines and live mosquitoes, dengue specific monoclonal antibodies and PCR have all represented major advances in dengue diagnosis. However, an appropriate rapid, early and accessible diagnostic method useful both for epidemiological surveillance and clinical diagnosis is still needed. Also, tools that suggest a prognosis allowing for better management are also needed. Finally, laboratory infrastructure, technical expertise and research capacity must be improved in endemic countries in order to positively influence dengue surveillance, clinical case management and the development of new approaches to dengue control.

Animals↗
PubMed2004

Dengue vaccine: priorities and progress.

Dengue transmission has increased considerably in the past 20 years. Currently, it can only be reduced by mosquito control; however, the application of vector-control methods are labor intensive, require discipline and diligence, and are hard to sustain. In this context, a safe dengue vaccine that confers long-lasting protection against infection with the four dengue viruses is urgently required. This review will discuss the requirements of a dengue vaccine, problems, and advances that have been made. Finally, new targets for research will be presented.

Animals↗
PubMed2004

Dengue 3 epidemic, Havana, 2001.

In June 2001, dengue transmission was detected in Havana, Cuba; 12,889 cases were reported. Dengue 3, the etiologic agent of the epidemic, caused the dengue hemorrhagic fever only in adults, with 78 cases and 3 deaths. After intensive vector control efforts, no new cases have been detected.

Adolescent↗
PubMed2004

Oxidative stress in adult dengue patients.

An association between viral diseases and increased oxidative stress has been suggested. The time course of serum levels of total antioxidant status (TAS), peroxidation potential (PP), glutathione (GSH), lipid peroxidation measured as hydroperoxides, and malondyaldehyde and 4-hydroxyalkenals (MDA + 4-HDA), as well as antioxidant enzymatic activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx), were measured in 22 serologically confirmed dengue patients. Most of the patients had dengue fever and three of them had dengue hemorrhagic fever. The redox parameters were compared with those of age- and sex- matched controls. No significant difference was observed for levels of GSH and TAS between patients and controls. Levels of PP, MDA + 4-HDA, and SOD were significantly higher. Levels of GPx and total hydroperoxides were significantly lower in patients in comparison with controls. These findings suggest that the alteration in redox status could result of increased oxidative stress and it may play a role in the pathogenesis of the disease.

Adult↗
PubMed2003

[Quality control of the serological diagnosis of dengue in laboratories throughout the Americas, 1996-2001].

OBJECTIVE: To report the results from participating laboratories for four external quality control proficiency tests of dengue serological diagnosis that were carried out in the Region of the Americas in the period of 1996-2001. METHODS: External quality control proficiency tests of dengue serological diagnosis were carried out in 1996-1997, 1998-1999, 1999-2000, and 2000-2001. Panels made up of 20 serum samples (12 of them positive for dengue IgM antibodies) were sent to participating laboratories in the Region. The sera were negative for HIV antibodies, hepatitis C virus antibodies, and hepatitis B surface antigen. The sera were stored at -20 degrees C until they were sent in refrigerated shipments to the participating laboratories. The presence of IgM antibodies was determined through IgM-capture enzyme-linked immunosorbent assay (ELISA), while the IgG antibody titer was determined by hemagglutination inhibition or by IgG ELISA. The results of the IgM antibody testing that differed from those of the reference center were considered discordant. The IgG antibody titer was considered discordant when the results differed by two dilutions or more with respect to the reference center's results. RESULTS: A total of 27 laboratories received a total of 59 serum panels over the 1996-2001 period, and the results from testing 54 of those panels (91.5%) were sent back in. Of the total of 1 080 sera samples from those 54 panels, the results from 95.6% of the IgM antibody tests were concordant with the results from the reference center. With 47 of the 54 panels (87.0%) the participating laboratories' agreement with the reference center's results for the IgM antibody testing was 90.0% or higher. The laboratories sent back results from a total of 27 IgG antibody titer tests, and 22 of them (81.5%) coincided with those from the reference center. Considering the IgM antibody testing results from the four periods, the findings from 22 of the participating laboratories coincided with those from the reference center for at least 90% of the samples, and 13 of the laboratories were in complete concordance with the reference center. CONCLUSIONS: The majority of the participating laboratories showed an excellent level of performance in detecting dengue IgG and IgM antibodies. However, the deficiencies found in some instances confirm the need for continuing to improve laboratory diagnosis of dengue in the Region of the Americas.

Americas↗
PubMed2002

Dengue: an update.

This review is an update of dengue and dengue haemorrhagic fever (DHF) based on international and Cuban experience. We describe the virus characteristics and risk factors for dengue and DHF, and compare incidence and the case fatality rates in endemic regions (southeast Asia, western Pacific, and the Americas). The clinical picture and the pathogenesis of the severe disease are explained. We also discuss the viral, individual, and environmental factors that determine severe disease. Much more research is necessary to clarify these mechanisms. Also reviewed are methods for viral isolation and the serological, immunohistochemical, and molecular methods applied in the diagnosis of the disease. We describe the status of vaccine development and emphasise that the only alternative that we have today to control the disease is through control of its vector Aedes aegypti.

Adolescent↗
PubMed2002

Enhanced severity of secondary dengue-2 infections: death rates in 1981 and 1997 Cuban outbreaks.

OBJECTIVE: To understand the possible effect that length of time has on disease severity with sequential dengue infections. METHODS: Death and hospitalization rates for dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) per 10,000 secondary dengue-2 infections were compared in the same age group for two dengue-2 (DEN-2) epidemics in Cuba. The first DEN-2 epidemic affected all of Cuba in 1981; the second one, in 1997, impacted only the city of Santiago de Cuba. The sensitizing infection for DHF/DSS for each of the DEN-2 epidemics was dengue-1 (DEN-1) serotype virus, which was transmitted in 1977-1979, that is, 4 years and 20 years before the two DEN-2 epidemics. Using published seroepidemiological data from the cities of Havana and Santiago de Cuba, we estimated the rates at which persons aged 15-39 years old and those 40 years and older were hospitalized or died of DHF/DSS in Havana and in all of Cuba in 1981 and in just Santiago de Cuba in 1997. RESULTS: Among adults 15-39 years old the death rate per 10,000 secondary DEN-2 infections was 38.5 times as high in Santiago de Cuba in 1997 as in Havana in 1981. As a further indication of the increased severity coming with a longer period between the initial DEN-1 infection and the secondary DEN-2 infection, the case fatality rate for that same age group was 4.7 times as high in Santiago in 1997 as it was in Havana in 1981. CONCLUSION: We found a marked increase in severity with the longer of the two intervals (20 years) between an initial DEN-1 infection and a secondary DEN-2 infection. Such a difference may be due to subtle shifts in causative dengue strains or to changes with the passage of time in the circulating population of human dengue antibodies. These observations have important implications for dengue control, pathogenic mechanisms, and vaccine development.

Adolescent↗