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Do vaccinated cases transmit measles? A systematic review and meta-analysis.

INTRODUCTION: We reviewed evidence on whether vaccinated individuals can transmit measles and conducted a meta-analysis to understand transmission characteristics. METHODS: We searched and extracted data from peer-reviewed and gray literature and included studies reporting measles transmission events from vaccinated individuals. We meta-analyzed the data to calculate the median number of transmissions from vaccinated cases by measles burden, number of doses, and time since first and last dose. RESULTS: We identified 11,911 peer-reviewed and 22 gray literature records and included 33 articles in our review. Seventy individuals who had received 1 or more doses of measles-containing vaccine transmitted measles virus, resulting in 237 secondary cases. Vaccinated transmitters in eliminated areas were older (median age of 19 years (IQR: 3, 21)) than those in non-eliminated areas (median age 16 years; IQR 13, 18) (p = 0.12). Additionally, 91% (30/33) of studies provided data on subsequent transmission generations, leading to 812 measles cases traced back to vaccinated individuals, with a median of 4 (IQR: 1, 10) cases per vaccinated transmitter. CONCLUSION: Measles transmissions from vaccinated cases, although relatively uncommon, must be considered in public health investigations, as such transmissions can contribute to outbreaks.

Adolescent

Ethiopia missed opportunities for vaccination study: Cluster-randomized evaluation of 5-dose measles vaccine vials and a flexible open-vial policy, 2021-2022.

INTRODUCTION: In 2024, an estimated 95,000 people died from measles globally, largely from suboptimal coverage with the measles-containing vaccine (MCV). Health workers may defer vaccinating eligible children to avoid wasting doses from 10-dose MCV vials, which must be discarded six hours after opening. These missed opportunities for vaccination (MOV) reduce coverage and timeliness. Ethiopia, which provides MCV at 9 and 15 months, considered switching to 5-dose vials. METHODS: We conducted a 15-month, randomized controlled trial with a nested cross-sectional design in Ethiopia. Sixty woredas were randomized to: (1) policy-only, instructing health workers to open 10-dose vials for any number of eligible children, with additional stock for increased wastage; (2) 5-dose switch, combining this policy with replacement of 10-dose by 5-dose vials; or (3) control (routine 10-dose practice). Household and health-facility surveys at baseline and endline assessed effects on first-dose (MCV1) and second-dose (MCV2) coverage, MCV1 timeliness, and wastage. Generalized estimating equation models estimated net intervention effects versus control. We also estimated the government cost of a nationwide 5-dose switch. RESULTS: MCV1 coverage was similar between policy-only and control (adjusted risk difference [ARD] = -1%, 95%CI: -17%, 15%), with no significant differences in MCV1 timeliness or MCV2 coverage. In the 5-dose switch group, MCV1 coverage changed little (ARD = 1%, 95%CI: -17%, 18%), but timely MCV1 at 9 months (ARD = 18%, 95%CI: 7%, 28%) and MCV2 coverage (ARD = 17%, 95%CI: 1%, 34%) rose significantly, and wastage fell (ARD = -7%, 95%CI: -14%, -1%). By endline, 29% of 5-dose health workers opened vials ≥10 times monthly (none in control); caregivers in both intervention groups reported 11% fewer measles-related MOVs. A nationwide 5-dose switch was estimated to save 17% in procurement cost per fully vaccinated (two-dose) child. CONCLUSIONS: The combined 5-dose intervention improved MCV1 timeliness and MCV2 coverage and reduced wastage, addressing a key operational barrier and potentially supporting measles elimination in Ethiopia.

Humans

Emerging hantavirus risks in mass gatherings: epidemiology, diagnostic challenges, and outbreak preparedness.

Hantaviruses are emerging rodent borne zoonotic pathogens of increasing global public health concern because of their high mortality, expanding ecological distribution, and potential for international dissemination. Although traditionally associated with sporadic rural outbreaks, recent ecological disruption, climate variability, urbanization, and increased global mobility have heightened concerns regarding hantavirus risks in mass gathering settings. This review critically examines the epidemiology, transmission uncertainty, diagnostic and surveillance challenges, and preparedness strategies related to hantavirus infections in the context of mass gatherings, including religious events, refugee settlements, cruise tourism, sporting events, and temporary accommodations. Particular emphasis is placed on the 2026 multinational cruise ship associated outbreak linked to the MV Hondius, which highlighted vulnerabilities related to delayed diagnosis, international passenger dispersal, and uncertainties surrounding possible human to human transmission of Andes virus. Current evidence indicates that hantavirus transmission occurs primarily through inhalation of aerosolized rodent excreta; however, controversies regarding limited interpersonal transmission, environmental persistence, and asymptomatic infections continue to complicate risk assessment and outbreak preparedness. Diagnostic limitations, underreporting, insufficient environmental surveillance, and lack of mass gathering specific preparedness frameworks remain major public health challenges, especially in resource limited settings. Strengthening proactive preparedness through integrated One Health approaches, ecological surveillance, genomic monitoring, AI driven epidemic intelligence, and coordinated international response systems is essential for mitigating future risks. The review emphasizes the urgent need for multidisciplinary research and evidence based policy development to improve global preparedness against emerging hantavirus associated threats in increasingly interconnected mass gathering environments.

Humans

Pathways of onward HIV disclosure in relationships among young people living with vertically acquired HIV receiving antiretroviral therapy: A qualitative analysis from the BREATHER Plus trial, South Africa.

For young people living with HIV (YPLHIV) navigating their status since birth, managing onward disclosure of a potentially stigmatising condition in relationships is challenging, and may or may not lead to social support, with implications for wellbeing. In a clinical trial setting in KwaZulu-Natal, South Africa, we investigate how young people living with vertically acquired HIV navigate onward disclosure. Data were from the qualitative component of the BREATHER Plus randomised controlled trial evaluating the efficacy, safety and acceptability of short-cycle dolutegravir/tenofovir-based triple antiretroviral therapy (ART) in young people aged 12-19 years. We analyse data on 35 participants receiving ART engaged in clinical trials at the research site: 29 in longitudinal in-depth interviews (IDIs) and 12 across three focus group discussions (FGDs), including 6 in IDIs and FGDs. The Disclosure Processes Model was applied in the thematic analysis. Pre-disclosure was characterised by social assessments of potential confidants. During disclosure, reciprocal vulnerability and partial information-sharing were employed. Post-disclosure processes entailed linear and non-linear feedback trajectories, impacting future disclosures. The findings show that the study cohort of young people receiving ART navigated many bidirectional disclosure pathways to maintain social connections in relationships, and counselling guidelines need to be responsive to this.

Humans

First identification and molecular subtyping of Blastocystis spp. in donkeys in Aksaray province, Türkiye.

Blastocystis is a common intestinal protist worldwide that can infect humans and animals. Although its molecular epidemiology in Türkiye is mostly focused primarily on humans and livestock, equids have received limited attention despite their traditional roles and frequent contact with humans and other animals in rural environments. This study aimed to determine the molecular prevalence and subtype (ST) distribution of Blastocystis spp. in donkeys in Aksaray Province, providing the first molecular data on donkeys in Türkiye. A total of 182 fresh fecal samples were collected from donkeys in nine villages within Aksaray province. Genomic DNA was extracted, and the small subunit ribosomal RNA (SSU rRNA) gene fragment of Blastocystis spp. was amplified via PCR analysis. Positive isolates were sequenced bidirectionally for identification and subsequent phylogenetic analysis of Blastocystis in donkeys. The overall molecular prevalence of Blastocystis spp. in donkeys was 4.4% (8/182). The infection rate was higher in young donkeys (under 3 years old; 8.33%) than in adults (3 years or older; 2.46%). However, this difference was not statistically significant. Sequence analysis of the positive PCR products revealed the presence of one known livestock-specific subtype, ST10. Phylogenetic analysis showed that the ST10 isolates characterized in this study clustered with isolates identified from different hosts. This study provides the first molecular data on Blastocystis presence in donkeys in Türkiye. The exclusive detection of ST10 suggests potential cross-species transmission, likely facilitated by the traditional practice of co-housing donkeys with other animals in confined barns. These findings indicate that donkeys may contribute to Blastocystis transmission, underscoring the importance of a "One Health" approach in future epidemiological surveillance.

Animals

Transcriptomic insights into the coordinated regulation of signaling, apoptosis, immunity, and metabolism during Sinonovacula constricta larval metamorphosis.

Metamorphosis is a critical ontogenetic transition for marine bivalves, marking the shift from planktonic to benthic lifestyles, where successful transformation dictates survival. The razor clam Sinonovacula constricta is economically important; however, low larval metamorphosis rates remain a major bottleneck in seedling production. To elucidate the mechanisms governing this process, we performed a comparative transcriptome analysis of S. constricta larvae at pre- and post-metamorphosis stages using Illumina sequencing. A total of 3701 differentially expressed genes (DEGs) were identified, including 3254 up-regulated and 447 down-regulated genes. Functional annotation of the respective top 20 significantly up-regulated and down-regulated DEGs indicated their potential pivotal roles in signal transduction (e.g., up-regulated: CAV1, CHRNA2; down-regulated: APP, NOTCH1), cellular proliferation and differentiation (e.g., up-regulated: TUBA, EGF1; down-regulated: KIF23, TTC25), transcriptional and epigenetic regulation (e.g., up-regulated: NFIL3; down-regulated: OVO, HMX1), substance transport (e.g., up-regulated: LRP2, LRP1B; down-regulated: SLC51A, Slc33a1), substance metabolism (e.g., up-regulated: CPK3, CYP26A1; down-regulated: RDMT1, ADAC), immunomodulation (e.g., up-regulated: CPN2, CRISP2), and protein homeostasis (e.g., up-regulated: HSP27, NAS-27). Functional enrichment analysis further revealed that DEGs were significantly enriched in pathways related to signal transduction and developmental regulation (e.g., Ras, TNF), cell death and homeostasis (e.g., apoptosis), immune responses (e.g., Toll-like receptor), energy metabolism (e.g., lipid), cardiovascular related (e.g., Fluid shear stress), cell junction and architecture (e.g., Tight junction), and infectious disease (e.g., measles). These results suggest a synergistic interplay between signaling, apoptosis, immunity, and metabolism during S. constricta metamorphosis. This study advances our understanding of marine bivalve metamorphosis and offers candidate genes for further mechanistic studies.

Animals

Construction of an infectious clone of Spodoptera frugiperda densovirus and its biological characteristics.

Densoviruses are highly pathogenic to their insect hosts and have great potential for biocontrol. Spodoptera frugiperda densovirus (SfDV) was isolated from diseased larvae of Spodoptera frugiperda, while its biological functions remain unclear. Herein, we successfully constructed an infectious clone of SfDV. The S. frugiperda larvae transfected with the infectious clone exhibited anorexia, stunted growth, and reduced activity. Histopathological analysis further showed that the epidermis, fat body and trachea were infected instead of muscle and midgut tissues. Transmission electron microscopy (TEM) revealed that numerous virions of about 22 nm were distributed within both the nucleoplasm and cytoplasm of epidermal cells. Moreover, many virions were also found contained within vesicles in the cytoplasm. The replication kinetics of the rescued SfDV (rSfDV) was similar to that of the parental SfDV. The median lethal dose (LD50) and median lethal time (LT50) values of rSfDV were 6.63 × 107 viral genome copies (vgc), 5.23 d, respectively, which were also comparable to those of the parental SfDV. Taken together, the infectious clone of SfDV provides an important tool for further exploring the genome function, pathogenesis, and interactions with its hosts.

Animals

Glucocorticoids and placental 11βHSD2 - A systematic review of human studies and animal models.

CONTEXT: Elevated prenatal glucocorticoid (GC) exposure is linked to adverse offspring outcomes. The placental enzyme 11β-hydroxysteroid-dehydrogenase-type-2 (11βHSD2) protects the fetus by converting maternal derived cortisol to inactive cortisone. Although in vitro studies suggest GC mediated upregulation of 11βHSD2, in vivo evidence remains inconclusive. METHODS: PubMed, Embase, and PsycInfo were searched in October 2024 for human and mammalian animal studies on endogenous or exogenous GCs during pregnancy and associations with placental 11βHSD2 (mRNA, protein, activity, gene methylation). Narrative synthesis was conducted due to heterogeneity precluding meta-analysis. RESULTS: Eighteen studies (eight human, ten animal populations) met inclusion criteria. Exogenous GC exposure was associated with modifications in placental 11βHSD2 expression in animal models, with effects varying by substance, timing, and species. Dexamethasone trended towards increased expression in rodents, whereas betamethasone increased expression in non-human primates but not rodents. Human studies on endogenous GCs showed inconsistent associations with 11βHSD2 changes. In asthmatic pregnancies, moderate inhaled GC-use maintained enzyme activity compared to untreated patients. No convincing sex-specific trend emerged. CONCLUSIONS: GC exposure alters placental 11βHSD2 in a substance- and species-specific way; translational relevance remains limited based on current literature. Future studies should employ technological advances and include GC-sensitive biomarkers to clarify mechanisms of maternal-fetal stress transmission.

Female

Marine air promotes structural compaction and coating growth of soot aerosols after long-range transport from East Asia.

Soot aerosol, a key global warming contributor, undergoes morphological and chemical transformations during atmospheric transport, particularly in humidified marine environments. This study investigates morphology, mixing state, and aging mechanisms of soot particles collected in the Bohai Sea and Yellow Sea. Transmission electron microscopy analyses reveal that coated soot particles dominate the marine atmosphere, accounting for over 98 % of soot-containing particles, with a mean mixing state index (χ) of 0.83. The fractal dimension (Df) of soot particles is 1.84 ± 0.05 in the Northern Yellow Sea, 1.90 ± 0.08 in the Bohai Sea, and 1.96 ± 0.07 in the Southern Yellow Sea, indicating structural compaction during long-range transport. Correspondingly, the average Dp/Dcore ratios (particle to core size ratio) are 5.3 in the Bohai Sea, 4.2 in the Northern Yellow Sea, and 3.9 in the Southern Yellow Sea. Notably, those ratios are higher in marine environments compared to those observed during continental regional transport from northern to southern China (3.54), suggesting enhanced coating growth in humid marine air. The results highlight the important role of marine atmospheres in accelerating soot aging, which in turn leads to significantly stronger light absorption compared to soot in continental air. Our results highlight the necessity of incorporating compact morphologies, uniform mixing states, and thick coatings into optical models for accurate radiative forcing simulations.

Aerosols

How do women with a history of childhood sexual abuse experience the preconception and perinatal period? A qualitative systematic review.

CONTEXT: Child sexual abuse (CSA) is a public health issue that predominantly affects women and has both short- and long-term consequences. The perinatal period can represent a challenge, but also an opportunity to identify a history of CSA and to provide sensitive care that may help prevent the intergenerational transmission of trauma. AIM: To describe and understand the experiences and coping strategies of women who are survivors of child sexual abuse and are transitioning to motherhood. METHOD: We conducted a systematic review of qualitative studies according to a protocol registered in PROSPERO, following methodological standards and reporting the results according to the ENTREQ guideline. A search was conducted on five databases up to July 2025. Two authors independently selected the articles and assessed their methodological quality. Data were analysed using thematic synthesis and the confidence in the findings was evaluated according to GRADE-CERQual. RESULTS: We included 21 qualitative studies that resulted in six themes. The findings reveal how women who experienced child sexual abuse and are transitioning to motherhood may experience this stage with ambivalence-ranging from revictimisation to identity reconstruction-where perinatal care emerges as a potential healing vehicle throughout this process. CONCLUSIONS: The perinatal period becomes a window of opportunity to heal deep wounds, with perinatal care playing a key role. The findings support trauma-informed perinatal care, underpinned by reflective practice and a holistic approach. Further work is needed to improve the identification of child sexual abuse, enhance professional training and review current practices to ensure sensitive care.

Humans

Comparative genomic epidemiology of food- and patient-derived diarrheagenic Escherichia coli from sentinel surveillance in Southeast China.

Diarrheagenic Escherichia coli (DEC) remains an important foodborne pathogen, yet long-term comparative genomic surveillance data jointly characterizing food-derived and patient-derived isolates remain limited. This surveillance-based comparative study integrated antimicrobial susceptibility testing and whole-genome sequencing to characterize diarrheagenic Escherichia coli isolates recovered from food and patient sources in Lishui, Southeast China, during 2018-2025, with emphasis on occurrence, resistance profiles, genomic backgrounds, and plasmid replicon-associated features. Antimicrobial susceptibility testing was performed for 258 selected isolates, and whole-genome sequencing was conducted for a curated analytical subset of 204 isolates. The sequenced subset was used for diversity-oriented comparative genomic analysis rather than for unbiased prevalence estimation of the entire DEC collection. EAEC predominated in both sources, although food-associated occurrence was heterogeneous across categories, with the highest recovery rate observed in raw meat. Patient-derived isolates showed a broader overall resistance burden, whereas food-derived isolates retained substantial resistance to tetracycline, chloramphenicol, and florfenicol. Phylogenetic analysis showed partial overlap in genomic backgrounds between food-derived and patient-derived isolates, while representative resistance determinants displayed both broadly distributed and lineage-enriched patterns. Replicon-based plasmid profiling identified 42 plasmid types, including 12 detected in both sources, with IncF-related replicons predominating among these shared profiles. Several food-derived isolates carried multiple plasmid replicon types that were also observed in patient-derived isolates. Overall, food-derived and patient-derived DEC showed partial overlap in genomic backgrounds, resistance determinants, and replicon-defined plasmid profiles within this surveillance setting, while retaining source-associated heterogeneity. These findings should be interpreted as surveillance-based comparative evidence rather than as evidence of direct source attribution or transmission.

Humans

From buffalo to human: Klebsiella pneumoniae in high-somatic cell count milk as an overlooked link in the one health chain.

High somatic cell count (SCC) is a critical indicator of udder health and milk quality in buffalo milk production. However, in many low-income regions, SCC monitoring is often underemphasized, allowing a proportion of high-SCC buffalo milk to enter the food chain and potentially compromising food safety and public health. Klebsiella pneumoniae (K. pneumoniae) is a common zoonotic pathogen found in high-SCC milk, yet systematic investigations into the prevalence and characteristics in high-SCC buffalo milk remain limited. In this study, 23 K. pneumoniae strains were screened out from 460 bacterial isolates obtained from high-SCC buffalo milk samples from Guangxi, China, with an isolation rate of 5.0%. These isolates were comprehensively characterized using whole-genome sequencing and comparative genomic analyses. The results revealed that 78.26% (18/23) of the isolates shared high genomic similarity with the human reference strain ATCC 13883, and the ST37 clone exhibited a pronounced potential of cross-species transmission. All isolates harbored core adhesion factors and intrinsic resistance genes. Notably, several strains displayed high-risk features: strain 419 carried the K1 capsular serotype, strain 326 possessed a complete yersiniabactin synthesis gene cluster, and strain 320 exhibited a multidrug-resistant phenotype. Phenotypic assays further demonstrated a positive correlation between biofilm formation capacity and virulence in Galleria mellonella. Metabolic pathway enrichment analyses suggested that K. pneumoniae has undergone substantial adaptation to the nutrient-rich buffalo milk environment. Collectively, these findings confirm that raw high-SCC buffalo milk serves as a significant reservoir for high-risk zoonotic K. pneumoniae. While industrial thermal processing effectively eliminates viable pathogens, the resilient antimicrobial resistance determinants within these isolates pose a persistent risk of horizontal gene dissemination along the food chain, providing critical evidence for enhancing pre-processing milk quality regulations within a One Health framework.

Animals

Characterization and application potential of two newly isolated phages targeting the prevalent multidrug resistant Salmonella serovars in China.

The escalating global threat of multidrug resistant (MDR) Salmonella, a foodborne pathogen with animal-derived foods serving as the primary transmission vehicle, underscores the urgent need for effective lytic phages for biocontrol. From 142 environmental and farm samples in Shandong Province, we isolated 103 phages active against MDR S. Enteritidis and S. Typhimurium, which were the most prevalent Salmonella serovars in China. Two Siphoviridae phages vB-SenS-S1 and vB-SenS-SEC2 were selected for further study. With optimal multiplicities of infection (MOIs) of 10-2 (vB-SenS-S1) and 10-5 (vB-SenS-SEC2), both phages exhibited a 20 min latent period, yielding burst sizes of 52 and 37 PFU/cell, respectively. They also demonstrated stability across a range of temperatures (50-60 °C), pH levels (5-11), and after 1 h of UV exposure. Genomic analysis identified vB-SenS-S1 (43,002 bp, 47.04% GC) and vB-SenS-SEC2 (42,948 bp, 47.65% GC) as novel double-stranded DNA phages. Functional annotation confirmed the presence of genes essential for structural assembly, host lysis, and DNA replication/metabolism, and also verified the absence of resistance, virulence, and lysogeny-associated genes. Both phages vB-SenS-S1 and vB-SenS-SEC2 exhibited synergy with colistin and tetracycline. The synergy with colistin was particularly potent, leading to complete bacterial eradication in vitro. The in vivo therapeutic efficacy was further validated in both Galleria mellonella larvae and murine models of MDR Salmonella infection. Combination therapy with vB-SenS-SEC2 and colistin not only dramatically increased survival but also achieved a significant reduction in bacterial burden across multiple visceral organs of infected mice. Moreover, vB-SenS-S1 (108 PFU/mL) completely inhibited MDR Salmonella on chicken meat at 4 °C and -20 °C when initial contamination was ≤103 CFU/mL. This study not only expands the diversity of Salmonella phages but also highlights their potential as biocontrol agents in both clinical veterinary use and food decontamination, thereby enhancing food quality and safety at both the meat production source and the terminal product.

Animals