?Dengue Fever with Complications,? An Intermediate Reporting Category Between Dengue Fever and Dengue Hemorrhagic Fever Used in the Brazilian National Dengue Surveillance System
Background:
More than 3 million cases of Dengue Fever (DF) have been reported in Brazil in the last 20 years. The Brazilian Dengue Suveillance System (BDSS) adopts the World Health Organization (WHO) case definitions for DF and Dengue Hemorrhagic Fever (DHF). However, several severe cases do not fulfill the DHF case definition and an intermediate category denominated ?DF with Complications? (DFC) is also currently adopted.
Methods:
We characterized reported cases of DFC using the surveillance system database from 2000 to 2006 and attempted to estimate the proportion of DFC cases that would fulfill DHF criteria. Analysis was performed using Epinfo 6.04d.
Results:
12,585 cases of DFC were reported between 2000 and 2006, with 3,075 (31%) hospitalizations and 179 (1.4%) deaths. The highest number of cases (4,591) was reported in 2002, during the largest recorded epidemic in Brazil. The most frequent symptoms of DFC were: fever (96%), headache (91%), myalgia (85%) and retro-orbital pain (69%). Among warning or alert signs, 28% had abdominal pain, 0.5% had cardiopulmonary dysfunction, myocarditis, 2%; neurologic manifestation, 5%, painful hepatomegaly, and 11% had hypotension. During this time the average mortality rate was 5.3% for DHF and 1.4% for DFC. Among DFC cases, 79 (0.6%) met the DHF case-definition and were therefore misclassified. Additionally, reporting form fields were left blank in a subset of cases, making it impossible to determine whether cases fulfilled the criteria for DHF: 95 cases (0.8%) would have met DHF criteria but lacked data on a confirmatory test for dengue (serology or isolation); 53 (0.4%) cases would have met DHF criteria but lacked data on hemorrhagic manifestations; 58 (0.5%) cases would have met are all DHF criteria but lacked data on thrombocytopenia; 539 (4.3%) cases would have met all DHF criteria but lacked data on presence of plasma leakage. Most (93.5%) cases had missing information for 2 criteria needed to meet the DHF case-definition.
Conclusions:
Important variables on the DF reporting for were left blank, making it impossible to determine if a subset of DFC cases were misclassified DHF cases. Strategies must be developed to assure that clinicians properly evaluate suspected DF, DFC and DHF patients and complete all fields on reporting forms.
Board 280. http://www.iceid.org/info-spc.asp
Background:
More than 3 million cases of Dengue Fever (DF) have been reported in Brazil in the last 20 years. The Brazilian Dengue Suveillance System (BDSS) adopts the World Health Organization (WHO) case definitions for DF and Dengue Hemorrhagic Fever (DHF). However, several severe cases do not fulfill the DHF case definition and an intermediate category denominated ?DF with Complications? (DFC) is also currently adopted.
Methods:
We characterized reported cases of DFC using the surveillance system database from 2000 to 2006 and attempted to estimate the proportion of DFC cases that would fulfill DHF criteria. Analysis was performed using Epinfo 6.04d.
Results:
12,585 cases of DFC were reported between 2000 and 2006, with 3,075 (31%) hospitalizations and 179 (1.4%) deaths. The highest number of cases (4,591) was reported in 2002, during the largest recorded epidemic in Brazil. The most frequent symptoms of DFC were: fever (96%), headache (91%), myalgia (85%) and retro-orbital pain (69%). Among warning or alert signs, 28% had abdominal pain, 0.5% had cardiopulmonary dysfunction, myocarditis, 2%; neurologic manifestation, 5%, painful hepatomegaly, and 11% had hypotension. During this time the average mortality rate was 5.3% for DHF and 1.4% for DFC. Among DFC cases, 79 (0.6%) met the DHF case-definition and were therefore misclassified. Additionally, reporting form fields were left blank in a subset of cases, making it impossible to determine whether cases fulfilled the criteria for DHF: 95 cases (0.8%) would have met DHF criteria but lacked data on a confirmatory test for dengue (serology or isolation); 53 (0.4%) cases would have met DHF criteria but lacked data on hemorrhagic manifestations; 58 (0.5%) cases would have met are all DHF criteria but lacked data on thrombocytopenia; 539 (4.3%) cases would have met all DHF criteria but lacked data on presence of plasma leakage. Most (93.5%) cases had missing information for 2 criteria needed to meet the DHF case-definition.
Conclusions:
Important variables on the DF reporting for were left blank, making it impossible to determine if a subset of DFC cases were misclassified DHF cases. Strategies must be developed to assure that clinicians properly evaluate suspected DF, DFC and DHF patients and complete all fields on reporting forms.
Board 280. http://www.iceid.org/info-spc.asp