Adaptation to Land Degradation in Southeast Vietnam

A framework was developed to elucidate (1) the drivers of land degradation, (2) pressures, (3) local impacts and vulnerabilities and (4) adaptation strategies. The combination of participatory approaches, statistical data analysis, time series Landsat imagery and spatial data mining was tested in southeast Vietnam where the impacts of land degradation on the environment and economy are considerable. The major drivers of land degradation are climate, notably drought, and population density. The pressures include natural resource management and land use/cover change. A Landsat archive analysis showed an increase in agricultural land use from 31% to 50%, mostly at the expense of forests, from 1990 to 2019. Farmers adapted by investing in the irrigation of rice and dragon fruit, and by selecting their rainfed crops in line with the changing environment. The most vulnerable were the rural poor and farmers without access to land and water resources. The best protection against land degradation was prosperity, which is enhanced by the region’s location along Vietnam’s major national route, connecting major cities along a north–south axis. Our analysis shows that southeast Vietnam emerged as a region with an important human ecological resilience strengthened by increased prosperity. The current adaptation options and limitations warrant further research.status: publishe

Measuring serum beta2-microglobulin to predict long-term mortality in hemodialysis patients using low-flux dialyzer reuse

Nguyen Huu Dung,1 Nguyen Trung Kien,2 Nguyen Thi Thu Hai,1 Phan The Cuong,1 Nguyen Thi Thu Huong,3 Dao Bui Quy Quyen,4 Nguyen Minh Tuan,4 Do Manh Ha,2 Truong Quy Kien,2 Nguyen Thi Thuy Dung,2 Pham Quoc Toan,2 Hoang Trung Vinh,2 Tomoko Usui,5 Le Viet Thang21Bach Mai Hospital, Ha Noi, Vietnam; 2Military Hospital 103, Ha Noi, Vietnam; 3Ha Noi Kidney Hospital, Ha Noi, Vietnam; 4Cho Ray Hospital, Ho Chi Minh, Vietnam; 5University of Tokyo Hospital, Tokyo, JapanPurpose: Beta2-microglobulin (β2-M) is recognized as a surrogate marker relating to the mechanisms of dialysis-associated amyloidosis. Few studies have evaluated the association of serum β2-M with clinical outcome in hemodialysis patients using high-flux type. However, study on patients using low-flux dialyzer reuse has not been done yet.Patients and methods: Using serum β2-M level on predicting long-term mortality of hemodialysis patients was examined in 326 prevalent hemodialysis patients (45.59±14.46 years, hemodialysis duration of 47.5 (26–79) months, 186 males and 140 females). The patients were divided into 3 groups with equal number of patients, according to their serum β2-M levels: group A (n=109, serum β2-M concentration ≤55.7 mg/L), group B (n=109, serum β2-M level from 55.8 mg/L to 75.4 mg/L) and group C (n=108, serum β2-M concentration >75.4 mg/L).Results: During the follow-up period of 5 years, there were 75 all-cause deaths (23.0%). Kaplan–Meier analysis revealed that all-cause mortality in the higher β2-M group was significantly higher compared to that in the lower β2-M groups (p<0.001). Serum β2-M level was a significant predictor for all-cause mortality (AUC =0.898; p<0.001; Cut-off value: 74.9 mg/L, Se=93.3%, Sp=92.9%).Conclusion: Serum β2-M levels were a significant predictor of long-term mortality in hemodialysis patients, who use only low-flux dialyzers and reuse 6 times.Keywords: Beta2-microglobulin, mortality, hemodialysi

Antimicrobial Resistance Patterns of Staphylococcus Aureus Isolated at a General Hospital in Vietnam Between 2014 and 2021

Nguyen Van An,1,* Le Ha long Hai,2,3,* Vu Huy Luong,4,5 Nguyen Thi Ha Vinh,5,6 Pham Quynh Hoa,7 Le Van Hung,5,7 Nguyen Thai Son,1 Le Thu Hong,1 Dinh Viet Hung,8 Hoang Trung Kien,9 Minh Nhat Le,10,11 Nguyen Hoang Viet,12 Duc Hoang Nguyen,13 Ngai Van Pham,14 Ta Ba Thang,15 Tran Viet Tien,16 Le Huy Hoang17 1Department of Microbiology, Military Hospital 103, Vietnam Military Medical University, Hanoi, Vietnam; 2Department of Clinical Microbiology and Parasitology, Faculty of Medical Technology, Hanoi Medical University, Hanoi, Vietnam; 3Department of Biochemistry, Hematology and Immunology, National Hospital of Dermatology and Venereology, Hanoi, Vietnam; 4Department of Laser and Skin Care, National hospital of Dermatology and Venereology, Hanoi, Vietnam; 5Department of Dermatology and Venereology, Hanoi Medical University, Hanoi, Vietnam; 6Department of General Planning, National hospital of Dermatology and Venereology, Hanoi, Vietnam; 7Department of Microbiology, Mycology and Parasitology, National hospital of Dermatology and Venereology, Hanoi, Vietnam; 8Department of Psychiatry, Military Medical 103, Vietnam Military Medical University, Hanoi, Vietnam; 9Department of Immunology, Vietnam Military Medical University, Hanoi, Vietnam; 10Tay Nguyen Institute of Science Research, Vietnam Academy of Science and Technology, VAST, Hanoi, Vietnam; 11Antimicrobial Resistance Research Center, National Institute of Infectious Disease, Tokyo, Japan; 12Molecular Pathology Department, Faculty of Medical Technology, Hanoi Medical University, Hanoi, Vietnam; 13Cardiovascular Laboratories, Methodist Hospital, Merrillville, Indiana, USA; 14Medical Testing Center, Medlatec Group, Hanoi, Vietnam; 15Respiratory Center, Military Hospital 103, Vietnam Military Medical University, Hanoi, Vietnam; 16Department of Infectious diseases, Military Hospital 103, Vietnam Medical Military University, Hanoi, Vietnam; 17Department of Bacteriology, National of Hygiene and Epidemiology, Hanoi, Vietnam*These authors contributed equally to this workCorrespondence: Le Huy Hoang, Department of Bacteriology, National of Hygiene and Epidemiology, Hanoi, 100000, Vietnam, Tel + 84 977 803 986, Email [email protected]: Staphylococcus aureus is a commensal bacteria species that can cause various illnesses, from mild skin infections to severe diseases, such as bacteremia. The distribution and antimicrobial resistance (AMR) pattern of S. aureus varies by population, time, geographic location, and hospital wards. In this study, we elucidated the epidemiology and AMR patterns of S. aureus isolated from a general hospital in Vietnam.Methods: This was a cross-sectional study. Data on all S. aureus infections from 2014 to 2021 were collected from the Microbiology department of Military Hospital 103, Vietnam. Only the first isolation from each kind of specimen from a particular patient was analyzed using the Cochran–Armitage and chi-square tests.Results: A total of 1130 individuals were diagnosed as S. aureus infection. Among them, 1087 strains were tested for AMR features. Most patients with S. aureus infection were in the age group of 41– 65 years (39.82%). S. aureus isolates were predominant in the surgery wards, and pus specimens were the most common source of isolates (50.62%). S. aureus was most resistant to azithromycin (82.28%), erythromycin (82.82%), and clindamycin (82.32%) and least resistant to teicoplanin (0.0%), tigecycline (0.16%), quinupristin-dalfopristin (0.43%), linezolid (0.62%), and vancomycin (2.92%). Methicillin-resistant S. aureus (MRSA) and multidrug-resistant (MDR) S. aureus were prevalent, accounting for 73.02% and 60.90% of the total strains respectively, and the strains isolated from the intensive care unit (ICU) had the highest percentage of multidrug resistance (77.78%) among the wards.Conclusion: These findings highlight the urgent need for continuous AMR surveillance and updated treatment guidelines, particularly considering high resistance in MRSA, MDR strains, and ICU isolates. Future research focusing on specific resistant populations and potential intervention strategies is crucial to combat this rising threat.Keywords: Staphylococcus aureus, antimicrobial resistance, methicillin-resistant S. aureus, multidrug resistance, Hanoi, Vietna

Concomitant bacteremia in adults with severe falciparum malaria

Background Approximately 6% of children hospitalized with severe falciparum malaria in Africa are also bacteremic. It is therefore recommended that all children with severe malaria should receive broad-spectrum antibiotics in addition to parenteral artesunate. Empirical antibiotics are not recommended currently for adults with severe malaria. Methods Blood cultures were performed on sequential prospectively studied adult patients with strictly defined severe falciparum malaria admitted to a single referral center in Vietnam between 1991 and 2003. Results In 845 Vietnamese adults with severe falciparum malaria admission blood cultures were positive in 9 (1.07%: 95% confidence interval [CI], .37–1.76%); Staphylococcus aureus in 2, Streptococcus pyogenes in 1, Salmonella Typhi in 3, Non-typhoid Salmonella in 1, Klebsiella pneumoniae in 1, and Haemophilus influenzae type b in 1. Bacteremic patients presented usually with a combination of jaundice, acute renal failure, and high malaria parasitemia. Four bacteremic patients died compared with 108 (12.9%) of 836 nonbacteremic severe malaria patients (risk ratio, 3.44; 95% CI, 1.62–7.29). In patients with >20% parasitemia the prevalence of concomitant bacteremia was 5.2% (4/76; 95% CI, .2–10.3%) compared with 0.65% (5/769; 0.08–1.2%) in patients with  Conclusions In contrast to children, the prevalence of concomitant bacteremia in adults with severe malaria is low. Administration of empirical antibiotics, in addition to artesunate, is warranted in the small subgroup of patients with very high parasitemias, emphasizing the importance of quantitative blood smear microscopy assessment, but it is not indicated in most adults with severe falciparum malaria.</p

Age-seroprevalence curves for the multi-strain structure of influenza A virus

The relationship between age and seroprevalence can be used to estimate the annual attack rate of an infectious disease. For pathogens with multiple serologically distinct strains, there is a need to describe composite exposure to an antigenically variable group of pathogens. In this study, we assay 24,402 general-population serum samples, collected in Vietnam between 2009 to 2015, for antibodies to eleven human influenza A strains. We report that a principal components decomposition of antibody titer data gives the first principal component as an appropriate surrogate for seroprevalence; this results in annual attack rate estimates of 25.6% (95% CI: 24.1% - 27.1%) for subtype H3 and 16.0% (95% CI: 14.7% - 17.3%) for subtype H1. The remaining principal components separate the strains by serological similarity and associate birth cohorts with their particular influenza histories. Our work shows that dimensionality reduction can be used on human antibody profiles to construct an age-seroprevalence relationship for antigenically variable pathogens

Antimicrobial drug resistance of Salmonella enterica serovar typhi in Asia and molecular mechanism of reduced susceptibility to the fluoroquinolonesv

This study describes the pattern and extent of drug resistance in 1,774 strains of Salmonella enterica serovar Typhi isolated across Asia between 1993 and 2005 and characterizes the molecular mechanisms underlying the reduced susceptibilities to fluoroquinolones of these strains. For 1,393 serovar Typhi strains collected in southern Vietnam, the proportion of multidrug resistance has remained high since 1993 (50% in 2004) and there was a dramatic increase in nalidixic acid resistance between 1993 (4%) and 2005 (97%). In a cross-sectional sample of 381 serovar Typhi strains from 8 Asian countries, Bangladesh, China, India, Indonesia, Laos, Nepal, Pakistan, and central Vietnam, collected in 2002 to 2004, various rates of multidrug resistance (16 to 37%) and nalidixic acid resistance (5 to 51%) were found. The eight Asian countries involved in this study are home to approximately 80% of the world's typhoid fever cases. These results document the scale of drug resistance across Asia. The Ser83 -> Phe substitution in GyrA was the predominant alteration in serovar Typhi strains from Vietnam (117/127 isolates; 92.1%). No mutations in gyrB, parC, or parE were detected in 55 of these strains. In vitro time-kill experiments showed a reduction in the efficacy of ofloxacin against strains harboring a single-amino-acid substitution at codon 83 or 87 of GyrA; this effect was more marked against a strain with a double substitution. The 8-methoxy fluoroquinolone gatifloxacin showed rapid killing of serovar Typhi harboring both the single- and double-amino-acid substitutions