Root-knot nematodes (RKNs) are among the most damaging pests of agricultural crops. Meloidogyne is an extremely polyphagous genus of nematodes that can infect thousands of plant species. A few genes for resistance (R-genes) to RKN suitable for use in crop breeding have been identified, but virulent strains and species of RKN have emerged that render these R-genes ineffective. Secretion of RKN effectors targeting plant functions mediates the reprogramming of root cells into specialized feeding cells, the giant cells, essential for RKN development and reproduction. Conserved targets among plant species define the more relevant strategies for controlling nematode infection. The EFFECTOR18 (EFF18) protein from M. incognita interacts with the spliceosomal small nuclear ribonucleoprotein D1 (SmD1) in Arabidopsis (Arabidopsis thaliana), disrupting its function in alternative splicing regulation and modulating the giant cell transcriptome. We show here that EFF18 is a conserved RKN-specific effector that targets this conserved spliceosomal SmD1 protein in Solanaceae. This interaction modulates alternative splicing events produced by tomato (Solanum lycopersicum) in response to M. incognita infection. The alteration of SmD1 expression by virus-induced gene silencing in Solanaceae affects giant cell formation and nematode development. Thus, our work defines a promising conserved SmD1 target gene to develop broad resistance for the control of Meloidogyne spp. in plants.

Occult hepatitis B infection (OBI) is characterized by the presence of low levels of hepatitis B virus (HBV) DNA and undetectable HBsAg in the blood. The prevalence of OBI in blood donors in Asia ranges from 0.013% (China) to 10.9% (Laos), with no data available from Vietnam so far. We aimed to investigate the prevalence of OBI among Vietnamese blood donors. A total of 623 (114 women and 509 men) HBsAg-negative blood donors were screened for anti-HBc and anti-HBs by ELISA assays. In addition, DNA from sera was isolated and nested PCR was performed for the HBV surface gene (S); a fragment of the S gene was then sequenced in positive samples. The results revealed that 39% (n = 242) of blood donors were positive for anti-HBc, and 70% (n = 434) were positive for anti-HBs, with 36% (n = 223) being positive for both anti-HBc and anti-HBs. In addition, 3% of blood donors (n = 19) were positive for anti-HBc only, and 34% (n = 211) had only anti-HBs as serological marker. A total of 27% (n = 170) were seronegative for any marker. Two of the blood donors (0.3%) were OBI-positive and sequencing revealed that HBV sequences belonged to HBV genotype B, which is the predominant genotype in Vietnam.

Background: Arboviruses, including Dengue (DENV), Zika, and chikungunya, cause recurrent outbreaks of varying intensity in tropical countries. This study aimed to investigate other arboviruses, including Zika and chikungunya, in patients clinically suspected of Dengue and to characterize the circulating Dengue serotypes and genotypes in Northern Vietnam from 2020 to 2022. To date, information on this topic in the region has been limited. Methods: Multiplex real-time polymerase chain reaction (PCR) was used to detect Dengue, Zika, and chikungunya RNA, and DENV serotypes were identified via real-time reverse transcriptase PCR from 426 clinically Dengue suspected patients. Patients were screened for NS1 antigen and anti-DENV immunoglobulin (Ig) G/IgM antibodies. Phylogenetic analysis of DENV Capsid-premembrane gene sequences was performed to investigate genotype distribution. Results: Dengue was confirmed in 95% of cases, with no Zika or chikungunya RNA detected. DENV-2 was the predominant serotype (61%), followed by DENV-1 (31%) and DENV-4 (7%). Coinfections were observed, with DENV-1 and DENV-2 being the most common. In 2022, a high incidence of Dengue cases with warning signs and severe Dengue was observed, accompanied by elevated liver enzyme levels and reduced platelet counts. Phylogenetic analysis revealed that the DENV-1 and DENV-4 serotypes clustered with previously reported regional virus, while DENV-2 showed a shift from genotype Asian I to Cosmopolitan over the study period. Conclusions: This study underscores a significant rise in Dengue severity and shifts in DENV genotypes in recent years in Northern Vietnam, emphasizing the importance of understanding genotype dynamics and clinical dynamics for improving outbreak preparedness and response strategies.

The prevalence of hepatitis E virus (HEV) in the Vietnamese population remains underestimated. The aim of the present study was to investigate the seroprevalence of HEV IgG/IgM antibodies and the presence of HEV RNA in blood donors as a part of epidemiological surveillance for transfusion-transmitted viruses. Serum samples from blood donors (n = 553) were analysed for markers of past (anti-HEV IgG) and recent/ongoing (anti-HEV IgM) HEV infections. In addition, all serum samples were subsequently tested for HEV RNA positivity. The overall prevalence of anti-HEV IgG was 26.8% (n = 148/553), while the seroprevalence of anti-HEV IgM was 0.5% (n = 3/553). Anti-HEV IgG seroprevalence in male and female donors was similar (27.1% and 25.5%, respectively). A higher risk of hepatitis E exposure was observed with increasing age. None of the blood donors were HEV RNA positive, and there was no evidence of HEV viraemia. Although the absence of HEV viraemia in blood donors from Northern Vietnam is encouraging, further epidemiological surveillance in other geographical regions is warranted to rule out transfusion-transmitted HEV.

We evaluated the in vitro activity of cefiderocol in combination with either taniborbactam or xeruborbactam against cefiderocol-resistant, bla _NDM -positive Pseudomonas aeruginosa clinical isolates from Vietnam and Nigeria. Taniborbactam restored cefiderocol susceptibility in most isolates (20/21, 95.2%), while xeruborbactam had no effect. Resistance was reversed by dipicolinic acid, which confirmed New-Delhi Metallo-β-Lactamase (NDM-mediated) resistance. One isolate that was unresponsive to taniborbactam carried multiple copies of bla _NDM-1 . These findings highlight the species-specific limitations of xeruborbactam in P. aeruginosa .