Risk factors of dengue fever in an urban area in Vietnam: a case-control study.

BACKGROUND: Dengue is a mosquito-borne flavivirus present in many metropolitan cities of tropical countries. METHODS: During and after the dengue season (September 2018 to January 2019), we conducted a case-control study in order to determine the risk factors for dengue fever in Hanoi city, Vietnam. 98 dengue patients and 99 patients with other acute infections, such as Hepatitis B virus infection, were recruited at Department of Infectious Disease of Bach Mai national hospital in Hanoi. Patients were interviewed using a structured questionnaire covering demographic, housing, environmental factors and knowledge, attitude, and practice on dengue prevention and control. Univariate analysis and multivariable logistic regression were used to determine the risk factors of dengue status. RESULTS: The mean score of knowledge items and practice items was only 7.9 out of total 19 points and 3.9 out of total 17 points, respectively. While the mean score of attitude items was 4.8 out of total 6 points. Multivariable logistic regression indicated that older patients had lesser risk of getting dengue infection as compared to younger adults aged 16-30, and patients living in peri-urban districts were less likely to suffer of dengue fever than patients living in central urban districts (OR = 0.31; 95% CI 0.13-0.75). This study could not find any association with occupation, water storage habit, knowledge, attitude, or practice on dengue prevention. CONCLUSIONS: All patients had a relatively low level of knowledge and practice on dengue prevention and control. However, the attitude of the participants was good. We found that age group and living district were the risk factors correlated with the dengue status. Communication programs on raising dengue awareness should be repeated all year round and target particular groups of adolescents, younger adults, landlords and migrants from other provinces to improve their knowledge and encourage them to implement preventive measures against dengue fever.

Prevalence of Opportunistic Infections and Associated Factors in HIV-Infected Men Who Have Sex With Men on Antiretroviral Therapy in Bach Mai Hospital, Hanoi, Vietnam: A Case-Control Study.

OBJECTIVE: To investigate the distribution of opportunistic infections (OIs) and factors associated with acquiring OIs in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) in comparison to those of heterosexual patients. METHOD: A cross-sectional study was conducted on 82 HIV-infected MSM and 120 HIV-infected heterosexual men in Bach Mai Hospital, Hanoi, Vietnam. Demographical characteristics and clinical data were collected and analyzed using appropriate statistics (Mann-Whitney, Chi-square, Fisher's exact test, and logistic regression). RESULTS: The prevalence of OIs among MSM and heterosexual patients were 63.4% and 81.7%, respectively. The most frequent OI in the MSM group was human papilloma virus (HPV) (11%), followed by hepatitis B virus (8.5%), mycobacterium tuberculosis (7.3%), and Talaromycosis (2.4%). CONCLUSIONS: Multivariate logistic regression analysis showed that buying sex (odds ratio (OR) = 4, 95% confidence interval (CI): 1.13-14.25) and injecting drugs (OR = 13.05, 95% CI: 2.39-71.21) were associated with increased odds of having OIs in heterosexual patients while increasing age (OR = 1.1, 95% CI: 1.01-1.24) was correlated to increased odd of acquiring OIs in the MSM group. HIV-infected MSM accumulates OIs with increasing age, while heterosexual individuals increase opportunistic infections by buying sex or injecting drugs.

A clinic-based direct real-time fluorescent reverse transcription loop-mediated isothermal amplification assay for influenza virus.

Seasonal influenza virus causes acute respiratory tract infections, which can be severe in children and the elderly. At present, rapid influenza diagnostic tests (RIDTs) are popular at clinical sites because they enable early diagnosis and avoid unnecessary use of antibiotics; in addition, high risk patients with underlying disease can be given antiviral drugs. However, the sensitivity and specificity of some of those tests are relatively poor. To overcome these problems, nucleic acid-based molecular point-of-care tests have been developed; however, they are significantly more expensive than RIDTs. Previously, the authors developed real-time reverse transcription loop-mediated isothermal amplification (rRT-LAMP) assays using a quenching primer to detect influenza viruses. However, the assay is limited to laboratory use because it requires a nucleic acid purification step and preparation of reaction mixtures on ice. Therefore, the authors developed and validated direct rRT-LAMP assays that require no nucleic acid purification steps using commercial RNA isolation kits, and no storage and handling of reagents on ice. These assays can be performed within 10-30 min and require only mixing a clinical specimen with extraction reagent followed by addition of a lyophilized detection reagent. The established assay showed high sensitivity and specificity when validated using 310 clinical specimens. Thus, the assay is a powerful tool for molecular diagnosis of seasonal influenza virus infection in the clinic.

Survey of cellular immune status among HIV infected people living in community in Hanoi

From Aug 2001 to April 2002, a cross-sectional study was performed on 245 HIV infected patients living in community in Hanoi, by cytometric method using FACS-CALIBUR machine to count TCD4 and TCD8 lymphocytes. The control groups composes of 23 healthy persons. Results were as follows: Aged of patients: 16-50 among them the 21-30 age group accounts for 65.3%, male gender 90.6%. The absolute count of lympho cells in the patients group is lower than control, with the count of lymphocyte and the percentage of TCD4 lower significantly and 21.6% of patients having TCD4 lymphocyte count < 200/mm3. In the patient group, TCD8 lymphocytes count and its percentage is higher significantly than that of control group. 7.8% patients have occupational infection that the main is tuberculosis 59.7%, zona 15.8%, their 10.5% acquiring waisting syndrome.