Introduction: Antiviral resistance has been reported in seasonal influenza A viruses and avian influenza A(H5N1) viruses in Viet Nam, raising concerns about the efficacy of treatment. Methods: We analysed specimens from two sources during the period 2009–2012: influenza-positive samples from influenza-like illness patients at sentinel clinics in northern Viet Nam and isolates from patients with confirmed A(H5N1) infections. Pyrosequencing was used to detect mutations: H275Y [for A(H1N1) and A(H5N1)], E119V [for A(H3N2)] and I117V [for A(H5N1)]. A neuraminidase inhibition assay was used to determine the Inhibitory Concentration 50 (IC50) values for all influenza A and B isolates. Results: There were 341 influenza A positive samples identified; influenza A(H1N1)pdm09 was identified most frequently (n = 215). In 2009, oseltamivir resistance was observed in 100% (19 of 19) of seasonal A(H1N1) isolates and 1.4% (3/215) of A(H1N1)pdm09 isolates. This H275Y mutation was not found in influenza subtypes A(H5N1) or A(H3N2) isolates. Discussion: In Viet Nam, seasonal and A(H5N1) influenza vaccines are not currently available; thus, effective treatment is required. The presence of oseltamivir-resistant viruses is therefore a concern. Active surveillance for oseltamivir resistance among influenza viruses circulating in Viet Nam should be continued.

Curcuma zedoaria (Christm.) Rosc. is a popular traditional herb to treat digestive disorders in Asian tropical countries. Previous studies indicated the presence of sesquiterpenoids, diterpenoids, and curcuminoids with various bioactivities. To enrich the phytocomposition data of this plant, this investigation was conducted.The dried rhizomes of C. zedoaria were collected in Hai Phong City (Vietnam), extracted with methanol and fractionated with n-hexane, CH2Cl2 , and EtOAc. Compounds were isolated from n-hexane soluble fraction by open column chromatography combined with thin layer chromatography from fraction n-hexane. Their chemical structures were elucidated by 1D, and 2D NMR spectra and comparison with reported data. As a result, a phytochemical investigation was conducted to isolate six sesquiterpenes from C. zedoaria. Their chemical structures were elucidated to be curcumenol (1), procurcumenol (2), neoprocurcumenol (3), 13-hydroxygermacrone (4), zederone (5), and curcumalactone (6). Among isolated compounds, compounds 1, 2, 4, and 5 were reported from C. zedoaria. Meanwhile, neoprocurcumenol (3) and curcumalactone (6) are isolated from this species for the first time. Compound 5 exhibited a mild inhibitory effect on α-glucosidase with an IC50 of 99.45 ± 0.50 μg/mL.

Curcuma zedoaria (Christm.) Rosc. is a popular traditional herb to treat digestive disorders in Asian tropical countries. Previous studies indicated the presence of sesquiterpenoids, diterpenoids, and curcuminoids with various bioactivities. To enrich the phytocomposition data of this plant, this investigation was conducted.The dried rhizomes of C. zedoaria were collected in Hai Phong City (Vietnam), extracted with methanol and fractionated with n-hexane, CH2Cl2 , and EtOAc. Compounds were isolated from n-hexane soluble fraction by open column chromatography combined with thin layer chromatography from fraction n-hexane. Their chemical structures were elucidated by 1D, and 2D NMR spectra and comparison with reported data. As a result, a phytochemical investigation was conducted to isolate six sesquiterpenes from C. zedoaria. Their chemical structures were elucidated to be curcumenol (1), procurcumenol (2), neoprocurcumenol (3), 13-hydroxygermacrone (4), zederone (5), and curcumalactone (6). Among isolated compounds, compounds 1, 2, 4, and 5 were reported from C. zedoaria. Meanwhile, neoprocurcumenol (3) and curcumalactone (6) are isolated from this species for the first time. Compound 5 exhibited a mild inhibitory effect on α-glucosidase with an IC50 of 99.45 ± 0.50 μg/mL.

Curcuma zedoaria (Christm.) Rosc. is a popular traditional herb to treat digestive disorders in Asian tropical countries. Previous studies indicated the presence of sesquiterpenoids, diterpenoids, and curcuminoids with various bioactivities. To enrich the phytocomposition data of this plant, this investigation was conducted.The dried rhizomes of C. zedoaria were collected in Hai Phong City (Vietnam), extracted with methanol and fractionated with n-hexane, CH2Cl2 , and EtOAc. Compounds were isolated from n-hexane soluble fraction by open column chromatography combined with thin layer chromatography from fraction n-hexane. Their chemical structures were elucidated by 1D, and 2D NMR spectra and comparison with reported data. As a result, a phytochemical investigation was conducted to isolate six sesquiterpenes from C. zedoaria. Their chemical structures were elucidated to be curcumenol (1), procurcumenol (2), neoprocurcumenol (3), 13-hydroxygermacrone (4), zederone (5), and curcumalactone (6). Among isolated compounds, compounds 1, 2, 4, and 5 were reported from C. zedoaria. Meanwhile, neoprocurcumenol (3) and curcumalactone (6) are isolated from this species for the first time. Compound 5 exhibited a mild inhibitory effect on α-glucosidase with an IC50 of 99.45 ± 0.50 μg/mL.

Curcuma zedoaria (Christm.) Rosc. is a popular traditional herb to treat digestive disorders in Asian tropical countries. Previous studies indicated the presence of sesquiterpenoids, diterpenoids, and curcuminoids with various bioactivities. To enrich the phytocomposition data of this plant, this investigation was conducted.The dried rhizomes of C. zedoaria were collected in Hai Phong City (Vietnam), extracted with methanol and fractionated with n-hexane, CH2Cl2 , and EtOAc. Compounds were isolated from n-hexane soluble fraction by open column chromatography combined with thin layer chromatography from fraction n-hexane. Their chemical structures were elucidated by 1D, and 2D NMR spectra and comparison with reported data. As a result, a phytochemical investigation was conducted to isolate six sesquiterpenes from C. zedoaria. Their chemical structures were elucidated to be curcumenol (1), procurcumenol (2), neoprocurcumenol (3), 13-hydroxygermacrone (4), zederone (5), and curcumalactone (6). Among isolated compounds, compounds 1, 2, 4, and 5 were reported from C. zedoaria. Meanwhile, neoprocurcumenol (3) and curcumalactone (6) are isolated from this species for the first time. Compound 5 exhibited a mild inhibitory effect on α-glucosidase with an IC50 of 99.45 ± 0.50 μg/mL.

Curcuma zedoaria (Christm.) Rosc. is a popular traditional herb to treat digestive disorders in Asian tropical countries. Previous studies indicated the presence of sesquiterpenoids, diterpenoids, and curcuminoids with various bioactivities. To enrich the phytocomposition data of this plant, this investigation was conducted.The dried rhizomes of C. zedoaria were collected in Hai Phong City (Vietnam), extracted with methanol and fractionated with n-hexane, CH2Cl2 , and EtOAc. Compounds were isolated from n-hexane soluble fraction by open column chromatography combined with thin layer chromatography from fraction n-hexane. Their chemical structures were elucidated by 1D, and 2D NMR spectra and comparison with reported data. As a result, a phytochemical investigation was conducted to isolate six sesquiterpenes from C. zedoaria. Their chemical structures were elucidated to be curcumenol (1), procurcumenol (2), neoprocurcumenol (3), 13-hydroxygermacrone (4), zederone (5), and curcumalactone (6). Among isolated compounds, compounds 1, 2, 4, and 5 were reported from C. zedoaria. Meanwhile, neoprocurcumenol (3) and curcumalactone (6) are isolated from this species for the first time. Compound 5 exhibited a mild inhibitory effect on α-glucosidase with an IC50 of 99.45 ± 0.50 μg/mL.

Objective:Highly pathogenic avian influenza A(H5N1) is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1) in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1) specific antibodies in 4% of poultry market workers (PMWs). We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1) among PMWs in Hanoi, Thaibinh and Thanhhoa provinces.Methods:We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1) viruses that have circulated in Viet Nam since 2004.Results:The overall seroprevalence was 6.1% (95% confidence interval: 4.6–8.3). The highest proportion (7.2%) was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3%) were slaughterers or sellers of poultry.Discussion:The continued circulation and evolution of influenza A(H5N1) requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian–human transmission of influenza A(H5N1) in Viet Nam.

BACKGROUND: The diagnosis of influenza based on clinical grounds alone may be inaccurate, because the presenting symptoms of influenza are similar to those caused by other infectious agents. We evaluate two influenza rapid tests, SD BIOLINE Influenza Ag (Standard Diagnostic inc., Yongin, Korea) and QuickVueTM Influenza Test (Quidel corporation, San Diego, USA) with influenza virus culture and RT-PCR. METHODS: The two commercially available rapid test kits, SD BIOLINE Influenza Ag and QuickVueTM Influenza Test, for influenza virus detection were evaluated with 189 respiratory specimens collected during Dec. 2004 to Nov. 2005 in Vietnam and compared with viral culture and RT-PCR. RESULTS: Overall, the SD BIOLINE Influenza Ag and QuickVueTM Influenza Test showed high sensitivities (88.4% and 82.6%, respectively) and high specificities (99.0% and 99.0%, respectively), high positive predictive value (PPV) (98.7% and 98.6%, respectively) and high negative predictive value (NPV) (91.1% and 87.2%, respectively). CONCLUSION: Both SD BIOLINE Influenza Ag and QuickVueTM Influenza Test were easy to perform and showed high sensitivity and can be used as an additional tool for rapid diagnosis of influenza virus.
Diagnosis ; Gyeonggi-do ; Immunoassay* ; Influenza, Human* ; Membranes* ; Orthomyxoviridae* ; Sensitivity and Specificity ; Vietnam