Is dengue and malaria co-infection more severe than single infections? A retrospective matched-pair study in French Guiana.
ABSTRACT Dengue and malaria are two major arthropod-borne infections in tropical areas, but dual infections were only described for the first time in 2005. Reports of these concomitant infections are scarce and there is no evidence of more severe clinical and biological pictures than single infections.
To compare co-infections to dengue alone and malaria alone, a retrospective matched-pair study was conducted between 2004 and 2010 among patients admitted in the emergency department of Cayenne hospital, French Guiana.
104 dengue and malaria co-infection cases were identified during the study period and 208 individuals were matched in two comparison groups: dengue alone and malaria alone. In bivariate analysis, co-infection clinical picture was more severe than separated infections, in particular using the severe malaria WHO criteria. In multivariate analysis, independent factors associated with co-infection versus dengue were: masculine gender, CRP level > 50 mg/L, thrombocytopaenia < 50 109/L, and low haematocrit <36% and independent factors significantly associated with co-infections versus malaria were red cells transfusion, low haematocrit < 36%, thrombocytopaenia < 50 109/L and low Plasmodium parasitic load < 0.001%.
In the present study, dengue and malaria co-infection clinical picture seems to be more severe than single infections in French Guiana, with a greater risk of deep thrombocytopaenia and anaemia.
- [show abstract] [hide abstract]
ABSTRACT: The last study describing the epidemiology of malaria in French Guiana was published 20 years ago. Yet French Guiana in the Americas along with Mayotte in the Indian Ocean is the only French territory with persisting endemic malaria. The purpose of this study is to provide an update based on official malaria surveillance data as well as on information from hospital records and various field surveys that have been carried out in recent years. Due to recurrent problems in collecting thorough, continuous, and consistent data, exact determination of incidence by plasmodium species has always been difficult in French Guiana. These problems include not only the remote location of endemic areas and intense unpredictable migration patterns but also poor data collection methods that do not always ensure consistency and homogeneity. Another factor hindering thorough collection of conventional epidemiological data is the requirement for rapid effective treatment in remote regions. The overall incidence of malaria in French Guiana appears to have remained stable since the beginning of the decade with an average of 3,920 case reports per year for an incidence rate of 20 per thousand, noting that three fourths of the 206,000 inhabitants of French Guiana live outside of endemic areas. Overall involvement of P. falciparum and P. vivax appears to be equal with P. malariae accounting for only 2.6% of cases. Trends in recent years indicate an increase in the number of cases involving P. vivax especially in the eastern zones, i.e. in the Oyapock focus where annual incidences in children have reached up to 500 per thousand and in the whole region located between Saint Georges and Cayenne. Conversely a decrease in endemic levels has been observed in western areas, especially for P. falciparum in the upper and middle focuses of the Maroni. Most zones now causing problems are located near migration points, particularly in relation with clandestine gold panning activities. In the coastal strip where the three main cities with most of the population are located, most reported cases are imported but local cases may occur. In general local transmission in these areas has been promptly controlled but trends indicate that incidence of these events may be rising. Anopheles darlingi is still recognized as the main vector but its role in transmission is less obvious in eastern areas where increasing evidence suggests that other species may contribute to maintaining endemic levels. These findings indicate that the extensive resources deployed in this French territory (public financing, health care network, public awareness campaigns, and training of health care personnel in diagnosis and treatment of malaria) have helped reduce the number of severe cases in an unfavorable epidemiological setting.Médecine tropicale: revue du Corps de santé colonial 03/2009; 69(1):19-25.
- [show abstract] [hide abstract]
ABSTRACT: A dengue fever outbreak occurred in the interior of French Guiana from November 2005 onwards. An investigation, with epidemiological, entomological and public health inputs, was initiated. Its objectives were to confirm the outbreak, to describe the emergence of dengue fever in the High Maroni area and to initiate a specific public health response. The investigation was conducted in Maripasoula in February 2006, the biggest community in that part of the country. Definition criteria were used for suspected, probable and confirmed cases of dengue fever. An entomological evaluation for larvae and adult mosquitoes was carried out. Some personal and collective vector control measures were set up by the vector control team. This survey identified 127 suspected dengue fever cases, whereas the epidemiological surveillance system detected only six probable and confirmed cases from the same place and for the same period. The proportion of dengue fever was higher in those people who had not travelled (23.5%) than within the population that had travelled (15.3%) in the three previous months (P = 0.01). Larvae of Stegomyia aegypti were found throughout the town, and adults were captured in 90.9% of the houses. This is the first time that a dengue fever outbreak has been described beyond the coastal region of this French overseas Department.The European Journal of Public Health 03/2009; 19(2):183-8. · 2.52 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Increased vascular permeability without morphological damage to the capillary endothelium is the cardinal feature of dengue haemorrhagic fever (DHF)/dengue shock syndrome (DSS). Extensive plasma leakage in various tissue spaces and serous cavities of the body, including the pleural, pericardial and peritoneal cavities in patients with DHF, may result in profound shock. Among various mechanisms that have been considered include immune complex disease, T-cell-mediated, antibodies cross-reacting with vascular endothelium, enhancing antibodies, complement and its products, various soluble mediators including cytokines, selection of virulent strains and virus virulence, but the most favoured are enhancing antibodies and memory T cells in a secondary infection resulting in cytokine tsunami. Whatever the mechanism, it ultimately targets vascular endothelium (making it a battlefield) leading to severe dengue disease. Extensive recent work has been done in vitro on endothelial cell monolayer models to understand the pathophysiology of vascular endothelium during dengue virus (DV) infection that may be translated to help understand the pathogenesis of DHF/DSS. The present review provides a broad overview of the effects of DV infection and the associated host responses contributing towards alterations in vascular endothelial cell physiology and damage that may be responsible for the DHF/DSS.FEMS Immunology & Medical Microbiology 08/2008; 53(3):287-99. · 2.68 Impact Factor