1.Drug resistance and the genotypic characteristics of rpoB and katG in rifampicin- and/or isoniazid-resistant Mycobacterium tuberculosis isolates in central Vietnam
Thi Binh Nguyen NGUYEN ; Thi Kieu Diem NGUYEN ; Van Hue TRƯƠNG ; Thi Tuyet Ngoc TRAN ; Van Bao Thang PHAN ; Thi Tuyen NGUYEN ; Hoang Bach NGUYEN ; Viet Quynh Tram NGO ; Van Tuan MAI ; Paola MOLICOTTI
Osong Public Health and Research Perspectives 2023;14(5):347-355
Objectives:
Tuberculosis (TB) and drug-resistant TB (DR-TB) are national health burdens in Vietnam. In this study, we investigated the prevalence of rifampicin (RIF) and/or isoniazid (isonicotinic acid hydrazide, INH) resistance in patients with suspected TB, and applied appropriate techniques to help rapidly target DR-TB.
Methods:
In total, 1,547 clinical specimens were collected and cultured using the BACTEC MGIT system (Becton Dickinson and Co.). A resazurin microtiter assay (REMA) was used to determine the proportions of RIF and/or INH resistance. A real-time polymerase chain reaction panel with TaqMan probes was employed to identify the mutations of rpoB and katG associated with DR-TB in clinical isolates. Genotyping of the identified mutations was also performed.
Results:
A total of 468 Mycobacterium tuberculosis isolates were identified using the REMA. Of these isolates, 106 (22.6%) were found to be resistant to 1 or both antibiotics. Of the resistant isolates, 74 isolates (69.8%) were resistant to isoniazid (INH) only, while 1 isolate (0.94%) was resistant to RIF only. Notably, 31 isolates (29.24%) were resistant to both antibiotics. Of the 41 phenotypically INH-resistant isolates, 19 (46.3%) had the Ser315Thr mutation. There were 8 different rpoB mutations in 22 (68.8%) of the RIF-resistant isolates. The most frequently detected mutations were at codons 531 (37.5%), 526 (18.8%), and 516 (6.3%).
Conclusion
To help prevent new cases of DR-TB in Vietnam, it is crucial to gain a comprehensive understanding of the genotypic DR-TB isolates.
2.Field and laboratory investigation of highly pathogenic avian influenza H5N6 and H5N8 in Quang Ninh province, Vietnam, 2020 to 2021
Trong Duc TRAN ; Suwicha KASEMSUWAN ; Manakorn SUKMAK ; Waraphon PHIMPRAPHAI ; Tippawon PRARAKAMAWONGSA ; Long Thanh PHAM ; Tuyet Bach HOANG ; Phuong Thi NGUYEN ; Thang Minh NGUYEN ; Minh Van TRUONG ; Tuan Pham DAO ; Pawin PADUNGTOD
Journal of Veterinary Science 2024;25(2):e20-
Background:
Avian influenza (AI) is a contagious disease that causes illness and death in poultry and humans. High pathogenicity AI (HPAI) H5N6 outbreaks commonly occur in Quang Ninh province bordering China. In June 2021, the first HPAI H5N8 outbreak occurred at a Quang Ninh chicken farm.
Objectives:
This study examined the risk factors associated with HPAI H5N6 and H5N8 outbreaks in Quang Ninh.
Methods:
A retrospective case-control study was conducted in Quang Ninh from Nov 2021 to Jan 2022. The cases were households with susceptible poultry with two or more clinical signs and tested positive by real-time reverse transcription polymerase chain reaction. The controls were households in the same village as the cases but did not show clinical symptoms of the disease. Logistic regression models were constructed to assess the risk factors associated with HPAI outbreaks at the household level.
Results:
There were 38 cases with H5N6 clade 2.3.4.4h viruses (n = 35) and H5N8 clade 2.3.4.4b viruses (n = 3). Compared to the 112 controls, raising poultry in uncovered or partially covered ponds (odds ratio [OR], 7.52; 95% confidence interval [CI], 1.44–39.27), poultry traders visiting the farm (OR, 8.66; 95% CI, 2.7–27.69), farms with 50–2,000 birds (OR, 3.00; 95% CI, 1.06–8-51), and farms with ≥ 2,000 birds (OR, 11.35; 95% CI, 3.07–41.94) were significantly associated with HPAI outbreaks.
Conclusions
Combining biosecurity measures, such as restricting visitor entry and vaccination in farms with more than 50 birds, can enhance the control and prevention of HPAI in Quang Ninh and its spread across borders.
3.Update on antibiotic resistance of common pathogenical bacteria isolated in Hue University of Medicine and Pharmacy Hospital
Dinh Binh TRAN ; Viet Quynh Tram NGO ; Thi Bao Chi LE ; Thi Chau Anh NGUYEN ; Hoang Bach NGUYEN ; Van Bao Thang PHAN ; Thi Khanh Linh NGUYEN ; Nu Xuan Thanh LE ; Thi Dang Khoa NGUYEN ; Thi Tuyen NGUYEN ; Thi Thuy UNG ; Thi Hai DINH ; Thi Ngoc Mai DUONG ; Minh Ngoc HOANG ; Viet Tu NGUYEN ; Le Bich Ngoc HOANG ; Tuan Khoi TRAN ; Doan Hieu TRAN ; Thi Tuyet Ngoc TRAN ; Van An LE
Hue Journal of Medicine and Pharmacy 2023;13(7):66-74
Backgroud: The aim of this study is to update on antibiotic resistance of common pathogenical bacteria isolated in Hue University of Medicine and Pharmacy Hospital (Hue UMP Hospital). Methodology: Use of the agar disk diffusion method to test the susceptibility to antimicrobial agents of 3709 bacterial strains from infected patients hospitalized in Hue UMP Hospital in 2020 - 2022. Results: Among 3709 strains of pathogenical bacteria isolated, S.aureus was found with the rate of 29.9%, followed by E. coli (24.5%), Pseudomonas aeruginasa (17.8%), Enterococcus spp. (11.8%), Klebsiella spp (9.7%) and Acinetobacter spp (4.1%). The proportion of bacterial isolates has changed, but Staphylococcus aureus is still highest rate. S.aureus is resistant to many antibiotics, but MRSA strains have decreased significantly, from 73.3% in 2020 to 62.5% in 2022. Pseudomonas aeruginosa was resistant to some of the group A recommended antibiotics such as ceftazidime, piperacillin-tazobactam with the rate of 56.6% and 48.7%. The percentage of E. coli with ESBL strains (+) was at 28.2% - 30.3%. Enterococus spp strains are still sensitive to vancomycin (83.1% - 91.9%). The rate of Klebsiella ESBL (+) is only 6.9% to 8.2%. The strains of Acinetobacter spp were highly resistant to Piperacillin (100%) and Ceftriaxone (96.5%) but they are still sensitive to imipenems 70 - 71%, highly sensitive to Doxycillin (95.2%) and Cefotaxime (88.4%). Conclusion: Many bacterial strains are resistant to many commonly antibiotics. Providing timely, regular, and effective management of antibiotic resistance patterns for common pathogenic bacteria in hospitals, will help reduce the risk of bacterial resistance.