Dengue virus (DENV) has become a global health threat with about half of the world’s population at risk of infection. Although the disease caused by DENV is self-limiting in the first infection, the antibody-dependent enhancement (ADE) effect increases the mortality in the second infection with a heterotypic virus. Since there is no specific efficient medicine in treatment, it is urgent to develop vaccines to prevent infection and disease progression. Currently, only a live attenuated vaccine, chimeric yellow fever 17D—tetravalent dengue vaccine (CYD-TDV), has been licensed for clinical use in some countries, and many candidate vaccines are still under research and development. This review discusses the progress, strengths, and weaknesses of the five types of vaccines including live attenuated vaccine, inactivated virus vaccine, recombinant subunit vaccine, viral vectored vaccine, and DNA vaccine.

Background: Aedes (Stegomyia) albopictus (Skuse, 1894) is the main vector of dengue virus in China. The resistance to insecticides is a huge obstacle for the control of this species, and determining its resistance status and mechanisms in China is essential for the implementation of vector management strategies. Methods: We have investigated the larval and adult resistance status of Ae. albopictus to deltamethrin in eight field populations in China. Mutations at the voltage-gated sodium channel gene, related to the knockdown resistance (kdr) effect, were detected by sequencing of PCR products. The eight field populations were examined for pyrethroid resistance using the World Health Organization standard bioassays, and the association between the mutations and phenotypic resistance was tested. Results: The eight field populations of larvae of Ae. albopictus in China exhibited high resistance to deltamethrin; the RR₅₀ values ranged from 12 (ZJ) to 44 (GZ). Adult bioassay revealed that Ae. albopictus populations were resistant to deltamethrin (mortality rate < 90%), except ZJ population (probably resistant, mortality rate = 93.5%). Long knockdown time in the field populations was consistent with low mortality rates in adult bioassay. F1534S mutation showed increased protection against deltamethrin in all populations except BJ and SJZ populations, whereas I1532T mutation showed increased protection against deltamethrin in only BJ population. Conclusion: There were different degrees of resistance to deltamethrin in field Ae. albopictus populations in China. The longest knockdown time and lowest mortality rate observed in Ae. albopictus population in Guangzhou indicate the severity of high resistance to deltamethrin. The patchy distribution of deltamethrin resistance and kdr mutations in Ae. albopictus mosquitoes suggests the necessity for resistance management and developing counter measures to mitigate the spread of resistance. Graphical

Background: The city of Guangzhou has been the epicenter of dengue fever in China since the 1990s, with Aedesalbopictus being the primary vector. The main method used to control vectors and prevent dengue fever has been the application of chemical insecticides; however, this control strategy has resulted in the development of resistance to these insecticides in mosquitoes. Here we report our investigation of the patterns of knockdown resistance (kdr) mutations in 15 field populations of Ae.albopictus collected from 11 districts in Guangzhou. Results: Four mutant alleles (V1016G, F1534S, F1534C, F1534L) were detected in domain II and III of the voltage-gated sodium channel (VGSC) gene. Various allele frequencies of kdr mutations were observed (3.1–25.9% for V1016G, 22.6–85.5% for F1534S, 0–29.0% for F1534L, 0.6–54.2% for F1534C). Seven kdr haplotypes (VF, VS, VL, VC, GF, GC, GS) were identified; the highest frequency of haplotypes was found for the single mutant haplotype VS (50.8%), followed by the wild-type VF haplotype (21.7%) and the single mutant haplotype VC (11.9%). Of the three double mutant haplotypes, GF was the most frequent (8.8%), followed by GC (1.2%) and GS (0.8%). Aedesalbopictus showed spatial heterogeneity in deltamethrin resistance in populations collected in Guangzhou. We also observed significant differences in haplotype frequency. The frequency of the VC haplotype was significantly higher in high-risk dengue areas than in low-risk ones. Conclusions: The kdr allele V1016G was discovered for the first time in Guangzhou. Genetic isolation in mosquito populations and long-term insecticide selection seem to be responsible for the persistent, patchy distribution of kdr mutant alleles. The small-scale spatial heterogeneity in the distribution and frequency of kdr mutations may have important implications for vector control operations and insecticide resistance management strategies. Graphical

Introduction: Acinetobacter baumannii (AB) is rising as a human pathogen of critical priority worldwide as it is the leading cause of opportunistic infections in healthcare settings and carbapenem-resistant AB is listed as a “super bacterium” or “priority pathogen for drug resistance” by the World Health Organization.Methods: Clinical isolates of A. baumannii were collected and tested for antimicrobial susceptibility. Among them, carbapenem-resistant and carbapenem-sensitive A. baumannii were subjected to prokaryotic transcriptome sequencing. The change of sRNA and mRNA expression was analyzed by bioinformatics and validated by quantitative reverse transcription-PCR.Results: A total of 687 clinical isolates were collected, of which 336 strains of A. baumannii were resistant to carbapenem. Five hundred and six differentially expressed genes and nineteen differentially expressed sRNA candidates were discovered through transcriptomic profile analysis between carbapenem-resistant isolates and carbapenem-sensitive isolates. Possible binding sites were predicted through software for sRNA21 and adeK, sRNA27 and pgaC, sRNA29 and adeB, sRNA36 and katG, indicating a possible targeting relationship. A negative correlation was shown between sRNA21 and adeK (r = -0.581, P = 0.007), sRNA27 and pgaC (r = -0.612, P = 0.004), sRNA29 and adeB (r = -0.516, P = 0.020).Discussion: This study preliminarily screened differentially expressed mRNA and sRNA in carbapenem-resistant A. baumannii, and explored possible targeting relationships, which will help further reveal the resistance mechanism and provide a theoretical basis for the development of drugs targeting sRNA for the prevention and treatment of carbapenem-resistant A. baumannii infection.

Background: The escalating global threat of carbapenem-resistant Acinetobacter baumannii (CRAB), classified by the WHO as a critical priority pathogen, underscores the urgent need for innovative therapeutic strategies. Traditional antibiotics face diminishing efficacy due to rapid resistance evolution, necessitating exploration of adjuvant therapies. Baicalein (BCL), a flavonoid from Scutellaria baicalensis, exhibits broad antimicrobial and resistance-modulating properties. This study aims to evaluate the synergistic effects and mechanisms of BCL combined with ceftazidime-avibactam (CAZ/AVI, CZA) against CRAB to address therapeutic gaps in managing these infections. Methods: Twenty CRAB clinical strains from a tertiary hospital were characterized using multi-locus sequence typing (MLST). Synergy between CZA and BCL was assessed via checkerboard assays (fractional inhibitory concentration index, FICI), time-kill kinetics, and biofilm inhibition assays. Transcriptomic profiling (RNA-seq) was performed to identify differentially expressed genes associated with synergistic effect. The change of sRNA and mRNA expression was validated by quantitative reverse transcription-PCR. Results: MLST revealed two dominant sequence types: ST208 and ST195. Checkerboard assays demonstrated significant synergism between CZA (8/4 µg/mL) and BCL (16 µg/mL), with a FICI of 0.5. Biofilm formation was significantly inhibited by the combination ( P < 0.05). Transcriptomic analysis identified 100 common DEGs across treatment groups, enriched in sulfur metabolism, butanoate metabolism, and amino acid degradation pathways. Notably, iron metabolism genes and major facilitator superfamily (MFS) transporters were differentially regulated by changing the concentration of BCL in drug combination. A negative correlation was observed between AbsR25 and MFS-transporter ( r = -0.689, P < 0.001). Conclusion: The combination of CZA and BCL exerts potent synergistic antibacterial and anti-biofilm activities against CRAB, with putative mechanisms involving the modulation of efflux pumps, iron homeostasis, and key metabolic pathways. The study not only establishes BCL as a promising adjuvant in the fight against CRAB infections, but also provides a molecular basis for optimizing combinatorial therapeutic regimens.

Mosquitoes are major vectors of pathogens causing diseases such as dengue, malaria, and Japanese encephalitis, imposing significant global public health and economic burdens. Traditional morphological approaches for mosquito research are limited by the reliance on specialized taxonomic expertise, the inability to distinguish cryptic species or immature life stages, and the susceptibility to environmental factors. DNA markers have emerged as indispensable tools to address these limitations. This review systematically summarizes the characteristics and applications of important DNA markers in mosquito population genetics research, covering core areas such as species identification, evolutionary and phylogenetic studies, invasion history and population genetic structure analysis, genetic mapping and quantitative trait locus (QTL) analysis, and genome-wide association studies (GWAS). This review highlights the pivotal role of DNA markers in advancing the understanding of mosquito biology and supporting the development of effective strategies for mitigating mosquito-borne diseases.