A systematic literature review was conducted to describe the epidemiology of dengue disease in Colombia. Searches of published literature in epidemiological studies of dengue disease encompassing the terms “dengue”, “epidemiology,” and “Colombia” were conducted. Studies in English or Spanish published between 1 January 2000 and 23 February 2012 were included. The searches identified 225 relevant citations, 30 of which fulfilled the inclusion criteria defined in the review protocol. The epidemiology of dengue disease in Colombia was characterized by a stable “baseline” annual number of dengue fever cases, with major outbreaks in 2001–2003 and 2010. The geographical spread of dengue disease cases showed a steady increase, with most of the country affected by the 2010 outbreak. The majority of dengue disease recorded during the review period was among those <15 years of age. Gaps identified in epidemiological knowledge regarding dengue disease in Colombia may provide several avenues for future research, namely studies of asymptomatic dengue virus infection, primary versus secondary infections, and under-reporting of the disease. Improved understanding of the factors that determine disease expression and enable improvement in disease control and management is also important.

/pdf/epidemiological-trends-of-dengue-disease-in-colombia-2000-3hyfm810x6.pdf

Epidemiological Trends of Dengue Disease in Colombia (2000-2011): A Systematic Review

This study evaluated if the Aedes aegypti population in the city of Cali, Colombia was composed of genetically distinct local populations with different levels of insecticide resistance and dengue vector competence. Insecticide resistance was assayed biochemically and was associated with varying levels of mixed-function oxidases and non-specific esterases. The genes encoding those enzymes were under selective pressure from insecticides used to suppress Ae. aegypti populations. Vector competence showed heterogeneity among the vector populations ranging from 19% to 60%. Population genetic analysis of random amplified polymorphic DNApolymerase chain reaction products, expressed as genetic distance, Wright's Fst, and migration rate (Nm), demonstrated moderate genetic differentiation among Ae. aegypti from four sites (Fst 0.085). The results from all characteristics evaluated in the study demonstrated spatial and temporal variation between Ae. aegypti populations. At any specific time, the local populations of Ae. aegypti were genetically differentiated and unique with respect to insecticide resistance and vector competence. Both charac- teristics changed independently.

Population dynamics of Aedes aegypti from a dengue hyperendemic urban setting in Colombia.

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.

/pdf/el-dengue-y-el-dengue-hemorragico-prioridades-de-32z39jqm42.pdf

El dengue y el dengue hemorrágico: prioridades de investigación

We have investigated the temporal distribution of dengue (DEN) virus serotypes in the department (state) of Santander, Colombia, in relation to dengue incidence, infection pattern, and severity of disease. Viral isolation was attended on a total of 1452 acute serum samples collected each week from 1998 to 2004. The infection pattern was evaluated in 596 laboratory-positive dengue cases using an IgG ELISA, and PRNT test. The dengue incidence was documented by the local health authority. Predominance of DEN-1 in 1998 and DEN-3 re-introduction and predominance in 2001-2003 coincided with outbreaks. Predominance of DEN-2 in 2000-2001 coincided with more dengue hemorrhagic fever (DHF). DEN-4 was isolated in 2000-2001 and 2004 but was not predominant. There was an annual increase of primary dengue infections (from 13.7 to 81.4%) that correlated with frequency of DEN-3 (r = 0.83; P = 0.038). From the total number of primary dengue infections DEN-3 (81.3%) was the most frequent serotype. DHF was more frequent in DEN-2 infected patients than in DEN-3 infected patients: 27.5 vs 10.9% (P < 0.05). DEN-3 viruses belonged to subtype C (restriction site-specific-polymerase chain reaction) like viruses isolated in Sri-Lanka and other countries in the Americas. Our findings show the importance of continuous virological surveillance to identify the risk factors of dengue epidemics and severity.

/pdf/temporal-distribution-of-dengue-virus-serotypes-in-colombian-k36bdk1mkn.pdf

Temporal distribution of dengue virus serotypes in Colombian endemic area and dengue incidence: re-introduction of dengue-3 associated to mild febrile illness and primary infection

In Bucaramanga, Colombia, dengue haemorrhagic fever (DHF) has become endemo-epidemic since 1992 A cross-sectional study covering a period of 10 years (February, 1992 to February, 2002) was undertaken in children under 13 years of age hospitalized at the University Hospital Observations were recorded on the clinical features, laboratory tests and the natural development of the disease A total of 763 patients were examined, of whom 617 were classified as having DHF according to the WHO criteria (91% Grade I, 615% Grade II, 217% Grade III and 75% Grade IV) One hundred forty six patients could not be classified The highest incidence took place in 1997, 1998 and 2001 Seventy four per cent of patients came from the metropolitan area of Bucaramanga; 48% were males; 03%, newborns; 118%, infants; 23%, pre-school children, and 649%, school children The most important clinical features were fever and haemorrhagic manifestations (100%); vomiting (60%); abdominal pain (57%); headache (50%); osteomyalgia (408%); hepatomegaly (33%), and macular rash (29%) Among the haemorrhagic manifestations we found petechiae (56%); positive tourniquet test (35%); gastrointestinal bleeding (34%), and epistaxis (32%) Serous effusion was found in 177% of cases Alarm signs of shock were found in 29% Fifty two per cent had leucopenia and 373% atypic lymphocytes Among other unusual manifestations were hepatitis, encephalopathy, alithiasic cholecystitis, acute renal failure, haemophagocytic syndrome and coinfections Of the 617 cases, 12 died (15%)

/pdf/dengue-hemorragico-en-ninos-diez-anos-de-experiencia-clinica-3sks7gqihk.pdf

Dengue hemorrágico en niños: diez años de experiencia clínica.

In 1947 the Colombian goverment established a campain for the erradication of Aedes aegypti in the country, following the recomendations of the Pan American Sanitaq Bureau. This campaign caused the disappearance of endemic dengue for approximately 20 years until it reappeared in explosive form with the epidemic of dengue 2 on the Atlantic Coast (1971-1972), followed by two documented large epidemics of dengue 3 (1975-1977) and dengue 1 in 1978. A summary is given of the activities developed by the virus laboratory of the National Institute of Health to aid the diagnosis of this disease in the country, including the first isolation of dengue 4 virus in 1982, the activity of dengue 1 ,- 2 and 4 viruses to the present time, the clinical and virological findings of a hemorragic case associated to dengue virus infection and a short report of the epidemic of Tumaco on the Pacific Coast, in which the simultaneous activity of dengue 1 and dengue 2 viruses was demonstrated. Finally, information is given on the current status of Aedes aegypti infestation in the country and about the activity of yellow fever virus in sylvatic foci close to heavily infected cities, detected in the month of January, 1987 in Colombia.

Martha O. Gaitán

Papers

Dengue en Colombia