In 2 epidemics of Dengue haemorrhagic fever in Bien Hoa, the predominant serotypes of dengue virus in the year 2000 and 2003 were Dengue-4 and Dengue-1, respectively. The number of clinical cases of children under 15 years old diagnosed as viral infection and unknown fever (n=1653), were higher than those diagnosed as Dengue fever/Dengue haemorrhagic fever (DF/DHF) (n=1122). The number of Dengue virus isolated from patients with viral infection and unknown fever (n=102) was higher than those isolated from DF/DHF cases (n=85). The number of Dengue positive MAC-ELISA cases in 2 years was 870 corresponding to a positive rate of 30.27%
Dengue ; Epidemiology ; Dengue Hemorrhagic Fever

The study was conducted at five communes from regions (Hµ T©y, Thõa Thiªn HuÕ, §µ N½ng, Kh¸nh Hßa, and Kiªn Giang province). The results indicated that the key breeding places of Aedes aegypti is different from region to region. In the Northern field trial, key breeding sites of Aedes aegypti are concrete tanks (65.6%); aquarium tanks (10.0%); and flower vases (15%). In the Central region, key breeding sites of Aedes Aegypti are wells, drums, ant traps, aquariums, toilette tanks. In the South, Aedes aegypti larvae are concentrated in big-size jars (67%), small-breeding sites of dengue vectors was changed after applying the intervention methods. It is clearly that the identification of key breeding places of Aedes aegypti are useful to propose the appropriate, effective control methods, and to evaluate the success of intervention measures.
Dengue ; Aedes ; Dengue Hemorrhagic Fever

Source of Aedes larvae was investigated in 200 households in provinces of Hµ T©y, Thõa thiªn HuÕ, §µ N½ng, Kh¸nh Hßa, Kiªn giang between 1998 - 2000. Mesocyclops were released to water containers and the waste water containers were eliminated. the results showed that in Northern area, mosquito and larvae population reduced by 100% after 13 months of project and maintained for several following months. In Central area, larvae population reduced by 90,7% and mosquito by 39.2% to 71.8%. In southern area, larvae population reduced by 97.7%, mosquito by 92.0% and there was not patient with dengue fever
Copepoda ; Dengue ; Dengue Hemorrhagic Fever

A descriptive prospective study of hospitalized Dengue including Dengue Fever (OF) and Dengue Haemorrhagic Fever (DHF) was undertaken in An Giang General Hospital. An Giang Province from April 2002 to May 2003. A first blood sample (BS) will be taken on admission to detect dengue antibody by Elisa (IgM and IgG) and virus isolation. The second BS will be drawn on discharge with the same test. If the patient is discharged before day 10th after the onset of fever, a third BS will be planned, for IgM and IgG too. In the hospital, all patients will be follow-up adequate platelet count and haematocrit. - There is 1009 patient selected (less than 15 years old), 5 DHF deaths due to DHF and 4 deaths due to others. Classification of the Dengue hospitalized cases: DF (28. 5%), DHF (49%) and DSS (10%). - The highest positive IgM rate is belong to DSS patient group (89%) and then DHF, the lowest rate is DF (34%). The virus isolated rate of the DSS patient group is highest (16.8%), and then DF (14.6%). DEN2 is predominant (with 84% of all virus isolated), and then DEN4 (8.8%). - On the admission, there are the overload for Dengue diagnosis. 12% cases with DF/DHF on the admission but they are typhoid fever, measles and viral infection on the discharge. - Clinical and laboratory findings are the more severe (thrombocytopenia and haemoconcentration), the more positive IgM rate and virus isolated. - For the correspondences between DF, DHF diagnosis. Clinical and laboratory findings according to WHO criteria: there are only 22.2% of DHF satisfied 4/4 WHO criteria, 39.2% satisfied 3/4 criteria and ultrasound is the test supported for these DF, DHF cases. - 71% confirmed DHF cases and 26% confirmed DSS cases have not thrombocytopenia and haemoconcentration. - The haemorrhagic manifestation just appear in 46.6% of DHF cases, even if DSS cases, there are only 56.2% cases have got the haemorrhagic manifestations.
Dengue Hemorrhagic Fever ; Dengue ; Diagnosis

Subject 6928 persons in 1454 households, T©n Minh commune, Th­êng TÝn district, Hµ T©y province where the dengue hemorrhagic fever occurred during 1988 -1992. Methods: survey of focus of Aedes aegypti, training, and education for public perception, release of Mesocyclops in the field training and monitoring the vector. Results: the education for enhancement of the public perception, release of mesocyclops and removal of the wasted objects gave the long-term social and economic efficacy. These were easy to implement and can be enlarged to other areas to actively control the epidemic fever/ dengue hemorrhagic fever
Dengue Hemorrhagic Fever ; Copepoda

In the year 2001, the Arbo virus Laboratory had received Dengue hemorrhagic fever samples from 19 provincial center for Preventive Medicine to isolate virus. 83 dengue viruses of 4 type were detected. Among them, the two main germs were dengue 2 and dengue 4. Viruses were detected mainly in infected children with hemorrhagic fever of I-II degree. Dengue 2 was the causative agent of DHF of I-III degree with a higher number of cases than other serotypes. 4.046 sera samples was examined by Mac ELISA, among them 56.13% was (+). However in Ma-ELISA(+) regions, there is no effective methods for dengue control.
Dengue ; Dengue Hemorrhagic Fever ; Child ; epidemiology ; serum

Background: Vietnam is one of eight countries with dengue fever / dengue hemorrhagic fever circulating seriously in the region. Some recent studies showed Mesocyclops dropping is one of effectively dengue fever/dengue hemorrhagic fever preventive approaches.\r\n', u'Objectives: To survey the distribution and role of mesocyclops in preventing dengue fever/dengue hemorrhagic fever in three communes in Thanh Hoa province.\r\n', u'Subjects and methods: The study was conducted in Dong Hai, Thanh Hoa, Hai Chau communes of Tinh Gia district, Nga Lien commune of Nga Son district. Research subjects are Mesocyclops collected in the artificial water containers and Adesaegypti mosquito larvae in water containers.\r\n', u'Results: Two species found are M.woutersi mesocyclops and M.thermo. M.woutersi exits in all of three local studied Mesocyclops rate in the water containers is 8.2%. Mesocyclops rate in water containers in Nga Son district is highest (13.26%) and in city is lower (13.26%). Of the experimental five species dropped on field, there are four species survived after a long-term period. Among them, M. Woutersi is highest (65.51%), M.aspericornis (15:52%). They breed and grow very fast, easy to adapt to natural conditions in Thanh Hoa.\r\n', u'Conclusion: The results show that Mesocyclops can be cultured in Thanh Hoa province.\r\n', u'\r\n', u'\r\n', u'
Dengue ; Dengue Hemorrhagic Fever ; Copepoda ; Densovirinae ;

In all 83 cases of under 16 years old parents with DHF treated in Khanh Hoa provincial hospital in the year 2000, prognostic factors were investigated. The role of gender in mortality was not clear. The role of nutritional factors was not determined. The age of 5-10 years old is the most vulnerable. The high morbidity of infants under 1 year old of age with severe DHF was high, possibly because of the decrease of neutralizing antibody of passive immune transferred from mother to child. In addition the increase of capillary permeability can play a role
Dengue ; Dengue Hemorrhagic Fever ; Diseases ; Prognosis

In the period of 1999 - 2001, there were some outbreaks of dengue fever (DF) and dengue hemorrhagic fever (DHF) in North Vietnam. From 185 blood samples collected from clinically suspected patients at National Institute of Epidemiology, there were 47 positive. By indirect immunofluorescent assay with monoclone antibiotics, 18 samples (38.3%) were identified as dengue virus of type I, 9 samples (19.2%) dengue virus of type II, 20 samples (42.6%) dengue virus of type IV. There was not dengue virus of type III
Dengue ; Dengue Hemorrhagic Fever ; Disease ; epidemiology

The surveillance of Dengue fever/Dengue hemorrhagic fever was conducted in 3 provinces Khanh Hoa, Quang Ngai, Quang Nam (Central Vietnam) during 2000-2002 year period. In terms of serology, virology, an active surveillance network was established involving all health stations, the relating institute, the Department of preventive medicine and MOH, using the standard MAC-ELISA bio-kit of National Institute of Hygien and Epidemiology. No case of the disease was reported, while in surrounding areas, cases were detected. MAC-ELISA kit has had high fidelity, giving quick results
dengue ; Dengue Hemorrhagic Fever ; Diseases ; epidemiology