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Introduction@#There are two methods of reverse transcription polymerase chain reaction (RT–PCR) that have been the common methods to detect influenza infections: conventional and real-time RT–PCR. From December 2017 to March 2018, several missed diagnoses of influenza A(H1)pdm09 using real-time RT–PCR were reported in northern Viet Nam. This study investigated how these missed detections occurred to determine their effect on the surveillance of influenza.@*Methods@#The haemagglutinin (HA) segments of A(H1N1)pdm09 from both real-time RT-PCR positive and negative samples were isolated and sequenced. The primer and probe sets in the HA gene were checked for mismatches, and phylogenetic analyses were performed to determine the molecular epidemiology of these viruses.@*Results@#There were 86 positive influenza A samples; 32 were A(H1)pdm09 positive by conventional RT–PCR but were negative by real-time RT–PCR. Sequencing was conducted on 23 influenza (H1N1)pdm09 isolates that were recovered from positive samples. Eight of these were negative for A(H1)pdm09 by real-time RT–PCR. There were two different mismatches in the probe target sites of the HA gene sequences of all isolates (n = 23) with additional mismatches only at position 7 (template binding site) identified for all eight negative real-time RT–PCR isolates. The prime target sites had no mismatches. Phylogenetic analysis of the HA gene showed that both the positive and negative real-time RT–PCR isolates were grouped in clade 6B.1; however, the real-time RT–PCR negative viruses were located in a subgroup that referred to substitution I295V.@*Conclusion@#Constant monitoring of genetic changes in the circulating influenza A(H1N1)pdm09 viruses is important for maintaining the sensitivity of molecular detection assays.
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To look for risk factors for dengue and community participation in dengue control in Binh Thuan Province, Vietnam, three communes with a low incidence of dengue and three with a high incidence, in Binh Thuan Province, were compared. Knowledge, perception and preventive practice of dengue were measured by means of a structured questionnaire. A check list of environmental observations was used to evaluate environmental factors. Focus group discussion was conducted to evaluate perceptions of key factors for dengue vector control and community participation. One hundred ninety households in 6 communes were included in the study. Several statistically significant differences between low and high incidence communities were identified. The factors associated with a higher risk of dengue fever on the logistic regression were occupation (farmer) (RR 7.94; 95% CI 2.29-27.55), number of children less than 15 years old in the household (RR 1.54; 95% CI 1.06-2.23), no experience with dengue fever in the household (RR 2.334; 95% CI 1.12- 4.88), a garden near the house (RR 2.22; 95% CI 1.18-4.17) and water containers having mosquito larvae (RR 1.64; 95% CI 1.02-2.62). Television was the most important source of information. There were differences in risk factors for dengue among communes with low and high incidences. Communication regarding dengue prevention should be improved in high incidence communes. Community participation in dengue vector control should be promoted to make the dengue control programs more efficient with greater coordination of resources.
Subject(s)
Demography , Dengue/etiology , Focus Groups , Health Knowledge, Attitudes, Practice , Health Surveys , Humans , Logistic Models , Risk Factors , VietnamABSTRACT
Background: Prostatic Specific Antigen (PSA), a helpful tumor maker in the diagnosis of prostate cancer, may rise due to many causes such as Digital Rectal Examination (DRE), Acute Urinary Retention (AUR), ect. Objective: To evaluate on the influences of some factors on the serum PSA level in Benign Prostatic Hyperplasia (BPH). Subjects and method: This study included 122 men who were diagnosed BPH with a mean age of 71.18 +/- 7.19 years (ranged 54-92). The patients were divided into 3 groups: DRE group included 60 patients, their blood samples were obtained before and after 24 hours; catheterization group included 35 patients who presented with AUR, their PSA values were determined before 48 hours and 2 weeks after elevation; the inflammation group consisted of 27 patients with symptoms of acute urinary tract infections, the PSA levels were evaluated before 48 hours and 4 weeks after anti-inflammatory therapy. Results: The PSA levels increased significantly in patients with larger prostate sizes (p<0.01, r = 0.492). PSA level tended to increase with age (p<0.05, r = 0.29). The PSA values changed 14.72 +/- 10.85% after DRE (p<0.05). After relief of urethral catheterization, PSA levels decreased 50.77 +/- 20.42% (p<0.05). After anti-inflammatory therapy, 51.59 +/- 21.87% (p<0.05). Conclusions: These results suggested that it may be the best way to perform DRE after obtaining serum PSA for analysis. Serum PSA concentration should not be determined when AUR and acute urinary tract infection.