Seroprevalence of anti-diphtheria toxoid antibody and implications for vaccination policy in Vietnam's South-central coast: a cross-sectional study.

BACKGROUND: Diphtheria is a re-emerging infectious disease and public health concern worldwide and in Vietnam with increasing cases in recent years. This study aimed to assess the anti-diphtheria toxoid antibodies status in Khanh Hoa Province and identify factors contributing to the vaccination policy in the south-central coast of Vietnam. METHODS: This was a cross-sectional study to evaluate the seroprevalence of anti-diphtheria toxoid antibodies among 1,195 participants, aged 5 - 40 years in Khanh Hoa Province, Vietnam. Immunoglobulin G antibody levels against diphtheria were detected using a commercial anti-diphtheria toxoid enzyme-linked immunosorbent assay (SERION ELISA classic Diphtheria Immunoglobulin G) and were categorized following the World Health Organization guidelines. RESULTS: The mean anti-diphtheria toxoid antibody levels were 0.07 IU/ml (95% Confidence Interval: 0.07-0.08). Anti-diphtheria toxoid antibody levels were found to be associated with age and history of diphtheria vaccination. The 5-15 years age group had the highest levels (0.09 IU/ml), while the older age group had the lowest antibody level (p < 0.001). Individuals who received three doses (adjusted Odds ratio: 2.34, 95%CI: 1.35 - 4.07) or 4+ doses (adjusted Odds ratio: 2.45, 95%CI: 1.29 - 4.64) had a higher antibody level compared to those who received only one dose regardless of age. CONCLUSION: It is crucial to promote routine vaccination coverage to over 95% for children under one year of age with three primary doses of the diphtheria-containing vaccine, including additional doses at 18 months and 7 years of age. Booster doses should be promoted and administered to adolescents and adults every 10 years.

Spatiotemporal Evolution of SARS-CoV-2 Alpha and Delta Variants during Large Nationwide Outbreak of COVID-19, Vietnam, 2021.

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions.

Outcomes of Patients With Thyroid Eye Disease Partially Treated With Teprotumumab.

PURPOSE: In response to the coronavirus (COVID-19) pandemic, teprotumumab production was temporarily halted with resources diverted toward vaccine production. Many patients who initiated treatment with teprotumumab for thyroid eye disease were forced to deviate from the standard protocol. This study investigates the response of teprotumumab when patients receive fewer than the standard 8-dose regimen. METHODS: This observational cross-sectional cohort study included patients from 15 institutions with active or minimal to no clinical activity thyroid eye disease treated with the standard teprotumumab infusion protocol. Patients were included if they had completed at least 1 teprotumumab infusion and had not yet completed all 8 planned infusions. Data were collected before teprotumumab initiation, within 3 weeks of last dose before interruption, and at the visit before teprotumumab reinitiation. The primary outcome measure was reduction in proptosis more than 2 mm. Secondary outcome measures included change in clinical activity score (CAS), extraocular motility restriction, margin reflex distance-1 (MRD1), and reported adverse events. RESULTS: The study included 74 patients. Mean age was 57.8 years, and 77% were female. There were 62 active and 12 minimal to no clinical activity patients. Patients completed an average of 4.2 teprotumumab infusions before interruption. A significant mean reduction in proptosis (-2.9 mm in active and -2.8 mm in minimal to no clinical activity patients, P < 0.01) was noted and maintained during interruption. For active patients, a 3.4-point reduction in CAS ( P < 0.01) and reduction in ocular motility restriction ( P < 0.01) were maintained during interruption. CONCLUSIONS: Patients partially treated with teprotumumab achieve significant reduction in proptosis, CAS, and extraocular muscle restriction and maintain these improvements through the period of interruption.

Thinning of the Skull Base and Calvarial Thickness in Patients With Idiopathic Intracranial Hypertension.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a disorder characterized by elevated intracranial pressure without secondary causes on neuroimaging. IIH typically occurs in young, obese female patients and, when severe, can cause permanent and irreversible vision loss. The association between skull base thinning in patients with intracranial hypertension and obesity has been previously reported; however, no study has reported these findings in IIH. The goal of our study is to determine whether IIH is independently associated with skull base and calvarial thinning. METHODS: A retrospective, matched case-control study was performed. Each patient diagnosed with IIH (case) was matched with a patient diagnosed with headache (control) by age, gender, and race. Patients were included if they underwent computed tomographic imaging of the head, maxillofacial, or orbits within 3 months of their diagnosis. Exclusion criteria were history of skull base or frontal bone pathology because of surgery or skull trauma, central nervous system infections, or incomplete radiologic data. Patient demographics, medical history, clinical examination, and skull base, calvarial, and zygoma thickness were recorded. Skull base thickness was measured by the height of the auditory canal in the coronal plane. Calvarial thickness was measured just anterior to the foramen rotundum in the coronal plane. Extracranial zygoma thickness was measured and used as an internal imaging control because the zygoma is not subject to intracranial forces. RESULTS: One hundred twenty-six patients were included in the study, 63 cases and 63 controls. Each group comprised 61 female patients (97%), 24 (38%) Caucasian, 23 (37%) black, 1 (2%) Asian, and 15 (24%) others. The average age was 31.5 ± 8.7 years. Patients with IIH were more likely to be obese (n = 60, 95%) compared with the control patients (n = 23, 37%, P < 0.001). All patients with IIH underwent lumbar puncture (LP) with an average opening pressure (OP) of 40.5 ± 15.6 cm H2O, whereas only 13 (20%) controls underwent an LP with a mean OP of 19.5 ± 8.5 cm H2O. There was no statistical difference in mean visual acuity between the IIH and control groups (logMar 0.22 [20/30] ± 0.45 vs logMar 0.09 [20/25] ± 0.30, P = 0.093, respectively). Compared with the controls, patients with IIH were more likely to have headache (97% vs 74%, P = 0.001), pulsatile tinnitus (48% vs 7%, P < 0.001), horizontal binocular diplopia (24% vs 4%, P = 0.006), confrontational visual field deficit (23% vs 2%, P = 0.003), and papilledema (74% vs 0%, P < 0.001). Patients with IIH had thinner skull base and calvarium width compared with the controls (mean skull base thickness 4.17 ± 0.94 mm vs 5.05 ± 1.12 mm, P < 0.001 and mean calvarial width 1.50 ± 0.50 mm vs 1.71 ± 0.61 mm, P = 0.024). Zygoma thickness was similar in both groups (mean zygoma thickness 1.18 ± 0.30 mm in the IIH group vs 1.26 ± 0.35 mm in the control group, P = 0.105). In a subgroup analysis controlling for obesity (body mass index >30 kg/m2), there was no statistically significant difference in skull base, calvarial, or zygoma thickness between obese and nonobese patients. CONCLUSIONS: Patients with IIH have thinner mean skull base and calvarial thickness compared with the controls. There was no difference in the mean extracranial zygoma thickness, which was the internal imaging control. Contrary to previous reports, we did not find an association between obesity and skull base or calvarial thinning. These findings suggest that IIH is associated with skull base and calvarial thinning.

Periocular non-tuberculous mycobacterial infection after autologous fat transfer with micro-needling and fractional radiofrequency skin resurfacing.

A 59-year-old woman with prior bilateral lower eyelid autologous fat transfer, subdermal micro-needling and fractional radiofrequency skin resurfacing presented with delayed left-sided preseptal cellulitis with small multinodular abscesses unresponsive to oral outpatient antibiotic regimens and inpatient intravenous antibiotics. Wound culture revealed Mycobacterium chelonae infection treated successfully with a 4-month regimen of clarithromycin and tedizolid without recurrence. This case highlights (1) the need for vigilance and a broad differential in delayed post-operative wound infections including non-tuberculous mycobacterial infections, (2) resolution of infection without recurrence on clarithromycin and novel tedizolid oral antibiotic therapy, and (3) that caution should be exercised when performing combination autologous fat transfers with subdermal micro-needling procedures as the breakdown in skin integrity may potentiate infection.

Long-Term Humoral Immune Response in Persons with Asymptomatic or Mild SARS-CoV-2 Infection, Vietnam.

Antibody response against nucleocapsid and spike proteins of SARS-CoV-2 in 11 persons with mild or asymptomatic infection rapidly increased after infection. At weeks 18-30 after diagnosis, all remained seropositive but spike protein-targeting antibody titers declined. These data may be useful for vaccine development.

A Unique Radiologic Case of Optic Nerve Infarction in a Patient With Mucormycosis.

ABSTRACT: This is a rare presentation of a unilateral optic nerve infarction of the left eye caused by mucormycosis in a 51-year-old man with poorly controlled Type 2 diabetes. Diffusion-weighted MRI of the orbit demonstrated extensive infarction of the left optic nerve with ipsilateral cavernous sinus thrombosis and periorbital adnexal inflammation. Left orbital exenteration and sinus debridement were performed, and mucormycosis involving the optic nerve sheath was confirmed on histopathology.

Multidisciplinary Management of Orbital Metastasis and Survival Outcomes.

PURPOSE: To study the multidisciplinary management and survival outcomes of orbital metastasis (OM). METHODS: All patients with a diagnosis of OM treated during 1999-2019 were included. Clinical data were retrospectively collected and analyzed. RESULTS: The study included 118 patients, 71 females and 47 males, with a median age of 61 years. The most common primary tumor types were breast carcinoma (43 patients), melanoma (17), and lung (13), thyroid (7), renal cell (6), and neuroendocrine carcinoma (6). Ninety-six patients had a known history of cancer at OM diagnosis. The median time from diagnosis of primary cancer to OM was 31 months (range, 0-304). In 22 patients, OM was the first sign of cancer. In 47 patients, the orbit was the only site of metastasis. The most common presenting features were restricted by extraocular motility (77 patients) and proptosis (61). Eight patients had enophthalmos. OM was diagnosed based on clinical history and imaging studies in 81 patients and orbital biopsy in 37. One hundred nine patients were treated with chemotherapy and immunotherapy, 75 with radiation, and 21 with palliative surgical resection. Eighty-two patients died during follow up. The median overall survival (OS) time after diagnosis of OM was 17 months (95% CI: 12-28). OM from renal cell carcinoma was associated with the best and OM from thyroid cancer with the worst OS. Patients with breast cancer had longer median survival (28 months; 95% CI: 15-60) than patients with lung, melanoma, neuroendocrine, or thyroid cancer. CONCLUSION: In this large series, breast cancer and melanoma were the most common causes of OM. Most patients had a known history of cancer at OM diagnosis and did not require orbital biopsy to confirm the diagnosis. Patients with renal cell carcinoma and breast carcinoma had the best prognosis after diagnosis of OM.

A serological framework to investigate acute primary and post-primary dengue cases reporting across the Philippines.

BACKGROUND: In dengue-endemic countries, targeting limited control interventions to populations at risk of severe disease could enable increased efficiency. Individuals who have had their first (primary) dengue infection are at risk of developing more severe secondary disease, thus could be targeted for disease prevention. Currently, there is no reliable algorithm for determining primary and post-primary (infection with more than one flavivirus) status from a single serum sample. In this study, we developed and validated an immune status algorithm using single acute serum samples from reporting patients and investigated dengue immuno-epidemiological patterns across the Philippines. METHODS: During 2015/2016, a cross-sectional sample of 10,137 dengue case reports provided serum for molecular (anti-DENV PCR) and serological (anti-DENV IgM/G capture ELISA) assay. Using mixture modelling, we re-assessed IgM/G seroprevalence and estimated functional, disease day-specific, IgG:IgM ratios that categorised the reporting population as negative, historical, primary and post-primary for dengue. We validated our algorithm against WHO gold standard criteria and investigated cross-reactivity with Zika by assaying a random subset for anti-ZIKV IgM and IgG. Lastly, using our algorithm, we explored immuno-epidemiological patterns of dengue across the Philippines. RESULTS: Our modelled IgM and IgG seroprevalence thresholds were lower than kit-provided thresholds. Individuals anti-DENV PCR+ or IgM+ were classified as active dengue infections (83.1%, 6998/8425). IgG- and IgG+ active dengue infections on disease days 1 and 2 were categorised as primary and post-primary, respectively, while those on disease days 3 to 5 with IgG:IgM ratios below and above 0.45 were classified as primary and post-primary, respectively. A significant proportion of post-primary dengue infections had elevated anti-ZIKV IgG inferring previous Zika exposure. Our algorithm achieved 90.5% serological agreement with WHO standard practice. Post-primary dengue infections were more likely to be older and present with severe symptoms. Finally, we identified a spatio-temporal cluster of primary dengue case reporting in northern Luzon during 2016. CONCLUSIONS: Our dengue immune status algorithm can equip surveillance operations with the means to target dengue control efforts. The algorithm accurately identified primary dengue infections who are at risk of future severe disease.

A Unique Presentation of Levamisole-Induced Antineutrophil- Cytoplasmic-Antibody-Positive Vasculitis Presenting as Inflammatory Orbitopathy.

A 35-year-old woman with a history of cocaine abuse presented with progressively worsening OS pain. Neuroimaging revealed a 3-cm ill-defined left orbital lesion involving the intraconal and extraconal spaces. The orbital mass was biopsied via an anterior orbitotomy approach. Pathology demonstrated prominent angiocentric granulomatous and lymphoplasmacytic inflammation consistent with vasculitis. Laboratory tests were significant for neutropenia, positive perinuclear antineutrophil cytoplasmic antibodies with high titer, and positive myeloperoxidase antibodies, consistent with levamisole-induced vasculitis. To the authors' knowledge, this is the first reported case of cocaine-levamisole-induced vasculitis presenting as orbitopathy.

Screening Criteria for Detecting Severe Ocular Injuries in the Setting of Orbital Fractures.

PURPOSE: Define incidence of severe ocular trauma in orbital fracture patients and determine if ocular signs and symptoms are useful predictors of severe ocular injuries. METHODS: Retrospective chart review was performed on all patients with orbital fractures between April 1, 2013, and December 31, 2014. Patients were included if they had radiographic evidence of acute fracture of at least one orbital wall and were evaluated by the Ophthalmology service. Demographics, concurrent injury data, and symptoms and signs of ocular trauma were collected. Concurrent ocular injuries were grouped by severity. Predictive signs or symptoms for severe ocular trauma were identified by stepwise logistic regression analysis. The threshold point for predictive signs and symptoms was detected by a receiver operating characteristic (ROC). RESULTS: Five-hundred-twelve patients were included. The most common mechanisms of injury were assault (39%), fall (25%), and motor vehicle accident (21%). The incidence of any concurrent ocular trauma was 75% (383/512), with 14% (70/512) being severe. Four signs and symptoms were predictors of severity: blurred vision (P < 0.0001), pain with eye movements (P < 0.0001), visual acuity worse than 20/40 in the ipsilateral eye (P < 0.001), and restricted motility (P < 0.001). The presence of 2 or more of these signs or symptoms was predictive of severe ocular trauma with high sensitivity (91%) and specificity (86%). CONCLUSIONS: In cooperative patients with acute orbital wall fractures, the presence of 2 or more signs or symptoms is predictive of severe ocular trauma and necessitates the need for urgent ophthalmic consultation.Severe ocular injury associated with orbital wall fracture is more likely in patients with 2 or more ophthalmic signs or symptoms.

Lutein Complex Supplementation Increases Ocular Blood Flow Biomarkers in Healthy Subjects.

Introduction: To investigate the effects of a lutein complex supplementation on ocular blood flow in healthy subjects. Materials and Methods: Sixteen healthy female patients (mean age 36.8 ± 12.1 years) were enrolled in this randomized, placebo-controlled, double-blinded, two-period crossover study. Subjects received daily an oral dose of the lutein with synergistic phytochemicals complex (lutein (10 mg), ascorbic acid (500 mg), tocopherols (364 mg), carnosic acid (2.5 mg), zeaxanthin (2 mg), copper (2 mg), with synergistic effects in reducing pro-inflammatory mediators and cytokines when administered together in combination) and placebo during administration periods. Measurements were taken before and after three-week supplementation periods, with crossover visits separated by a three-week washout period. Data analysis included blood pressure, heart rate, intraocular pressure, visual acuity, contrast sensitivity detection, ocular perfusion pressure, confocal scanning laser Doppler imaging of retinal capillary blood flow, and Doppler imaging of the retrobulbar blood vessels. Results: Lutein complex supplementation produced a statistically significant increase in mean superior retinal capillary blood flow, measured in arbitrary units (60, p = 0.0466) and a decrease in the percentage of avascular area in the superior (-0.029, p = 0.0491) and inferior (-0.023, p = 0.0477) retina, as well as reduced systolic (-4.06, p = 0.0295) and diastolic (-3.69, p = 0.0441) blood pressure measured in mmHg from baseline. Data comparison between the two supplement groups revealed a significant decrease in systemic diastolic blood pressure (change from pre- to post-treatment with lutein supplement (mean (SE)): -3.69 (1.68); change from pre- to post-treatment with placebo: 0.31 (2.57); p = 0.0357) and a significant increase in the peak systolic velocity (measured in cm/sec) in the central retinal artery (change from pre- to post-treatment with lutein supplement: 0.36 (0.19); change from pre- to post-treatment with placebo: -0.33 (0.21); p = 0.0384) with lutein complex supplement; data analyses from the placebo group were all non-significant. Discussion: In healthy participants, oral administration of a lutein phytochemicals complex for three weeks produced increased ocular blood flow biomarkers within retinal vascular beds and reduced diastolic blood pressure compared to placebo.

Characteristics of Extended-Spectrum ß-Lactamase-Producing Escherichia coli in Retail Meats and Shrimp at a Local Market in Vietnam.

BACKGROUND: Contamination of food with multiantibiotic-resistant bacteria, particularly extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae, is considered a potential source for the wide dissemination of ESBL-producing bacteria in communities. However, little is known about the extent of contamination of food with ESBL-producing bacteria in Vietnam. OBJECTIVE: This study was conducted to assess the characteristics of ESBL-producing Escherichia coli isolated from retail meats and shrimp in Nha Trang, Vietnam. MATERIALS AND METHODS: A total of 350 food samples (poultry [n=143], pork [n=147], and shrimp [n=60]) were purchased in July and November 2013 from a local market. ESBL-producing E. coli were isolated, and ESBL genotypes, phylogenetic groups, and antibiotic resistance profiles were determined. RESULTS: The prevalence of ESBL-producing E. coli in retail foods was 40.6%. ß-Lactamase-encoding genes of the CTX-M-1 (50.7%), CTX-M-9 (41.5%), TEM (59.9%), and SHV (2.8%) groups were detected singly or in combination. The percentages of single ESBL isolates harboring CTX-M-1 or -9 plus TEM groups were 35.2% and 16.2%, respectively. B1 was the most prevalent phylogroup in ESBL isolates from pork (44.7%), poultry (55.9%), and shrimp (72.7%). B2 was the least prevalent (4.2% and 4.8% for pork and poultry isolates, respectively). The prevalence of multidrug resistance (MDR; resistance to ≥ 3 antimicrobial groups) in ESBL-producing E. coli isolated from food was 85.9%. DISCUSSION AND CONCLUSIONS: This is the first report of the characteristics of ESBL-producing E. coli in retail foods in a local city in Vietnam. Our findings indicate that retail foods are contaminated with ESBL-producing E. coli, of which many were MDR. Further monitoring and public health efforts targeting food administration are needed to control the spread of ESBL-producing bacteria in communities.

Group 11 complexes of a bulky triazene ligand.

A new triazene ligand was prepared by the reaction of the bulky aryl azide, TerMesN3, (2,6-bis(2,4,6-trimethylphenyl)phenyl azide), with the bulky N-heterocyclic carbene (NHC), SIPr (N,N'-2,6-bis(diisopropylphenyl)-3,4-dihydroimidazol-2-ylidene). The steric bulk of these two groups leads to perpendicular bonding of the NHC-N3 plane and the aryl group which provides immense steric crowding around the triazene core. The corresponding π-conjugated triazene ligand was utilized as a neutral, monodentate ligand which results in monomeric Cu(I)Cl, Ag(I)OTf, and Au(I)Cl complexes. Instability of the π-conjugated triazene Au(I)Cl complex was observed, even under inert conditions. When dissolved and photolyzed in THF with workup in isopropanol, the compound decomposes forming [(SIPrNH)2Au(I)][Au(I)Cl2] a relatively stable compound to light, moisture, and water - alongside the formation of gold nanoparticles which were characterized using scanning electron microscopy with energy dispersive spectroscopy.

A SARS-CoV-2 recombinant spike protein vaccine (S-268019-b) for COVID-19 prevention during the Omicron-dominant period: A phase 3, randomised, placebo-controlled clinical trial.

Clinical trials of new vaccines based on existing variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are often impacted by the emergence of new virus variants. We evaluated the efficacy, immunogenicity, and safety of S-268019-b, a recombinant spike protein subunit vaccine based on the ancestral strain, for preventing symptomatic coronavirus disease 2019 (COVID-19) during the Omicron (BA.2)-dominant period in Vietnam. In this multicentre, phase 3, randomised (2:1), observer-blind, placebo-controlled crossover study, participants received 2 intramuscular doses (28 days apart) of either 10 µg of S-268019-b (Recombinant S-protein vaccine) or placebo. The primary endpoint was incidence of laboratory-confirmed symptomatic COVID-19 before crossover, with onset within 14 days following the second dose, in participants who were seronegative and reverse transcription polymerase chain reaction (RT-PCR)-negative at baseline. The secondary endpoints included immunogenicity and safety. In total, 8,594 participants were randomised (S-268019-b [n = 5,727]; placebo [n = 2,867]). Vaccine efficacy versus placebo was 39·1 % (95 % confidence interval [CI]:26·6-49·5; one-sided P = 0·0723). The incidence rate (95 % CI) of symptomatic COVID-19 was 776·41/1,000 person-years (682·04-880·19) in the S-268019-b group and 1272·87/1,000 person-years (1101·32-1463·57) in the placebo group. The geometric mean titres (95 % CI) of the SARS-CoV-2 neutralising antibody increased on Day 57 versus baseline with S-268019-b (34·66 [27·04-44·41] versus 2·50 (non-estimable) but not with placebo. There were no safety concerns regarding S-268019-b. S-268019-b did not demonstrate the targeted efficacy threshold against symptomatic COVID-19; however, findings were comparable with other prophylactic vaccines based on ancestor strain during the Omicron-dominant period. S-268019-b demonstrated immunogenicity and was well-tolerated. ClinicalTrials.gov identifier: NCT05212948.

Could prophylactic antivirals reduce dengue incidence in a high-prevalence endemic area?

Prophylactic drugs against dengue are currently under development. In this study, we explored how such prophylactic approaches might affect dengue cases in four communes of Nha Trang City, Vietnam. A community level dengue transmission survey indicated high levels of previous exposure to dengue (89.7%; 95% CI: 87.2,92.0). We fitted a spatially explicit model to an observed outbreak and simulated likely effectiveness of Case-Area Targeted Interventions (CATI) and One-Time Mass Distribution (OTMD) of drug and vector control strategies. Increasing radius and effectiveness and decreasing delay of CATI was most effective, with drugs being more effective in averting dengue cases than vector control. Using an OTMD approach early in the outbreak required the least number of treatments to avert a case, suggesting that OTMD strategies should be considered as pre-emptive rather than reactive strategies. These findings show that pre-emptive interventions can substantially reduce the burden of dengue outbreaks in endemic settings.

Pathogen genomic surveillance status among lower resource settings in Asia.

Asia remains vulnerable to new and emerging infectious diseases. Understanding how to improve next generation sequencing (NGS) use in pathogen surveillance is an urgent priority for regional health security. Here we developed a pathogen genomic surveillance assessment framework to assess capacity in low-resource settings in South and Southeast Asia. Data collected between June 2022 and March 2023 from 42 institutions in 13 countries showed pathogen genomics capacity exists, but use is limited and under-resourced. All countries had NGS capacity and seven countries had strategic plans integrating pathogen genomics into wider surveillance efforts. Several pathogens were prioritized for human surveillance, but NGS application to environmental and human-animal interface surveillance was limited. Barriers to NGS implementation include reliance on external funding, supply chain challenges, trained personnel shortages and limited quality assurance mechanisms. Coordinated efforts are required to support national planning, address capacity gaps, enhance quality assurance and facilitate data sharing for decision making.

Enhancing nicotine vaccine immunogenicity with liposomes.

A major liability of existing nicotine vaccine candidates is the wide variation in anti-nicotine immune responses among clinical trial participants. In order to address this liability, significant emphasis has been directed at evaluating adjuvants and delivery systems that confer more robust potentiation of the anti-nicotine immune response. Toward that end, we have initiated work that seeks to exploit the adjuvant effect of liposomes, with or without Toll-like receptor agonist(s). The results of the murine immunization study described herein support the hypothesis that a liposomal nicotine vaccine formulation may provide a means for addressing the immunogenicity challenge.

Safety and efficacy of the intranasal spray SARS-CoV-2 vaccine dNS1-RBD: a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: The live-attenuated influenza virus vector-based intranasal SARS-CoV-2 vaccine (dNS1-RBD, Pneucolin; Beijing Wantai Biological Pharmacy Enterprise, Beijing, China) confers long-lasting and broad protection in animal models and is, to our knowledge, the first COVID-19 mucosal vaccine to enter into human trials, but its efficacy is still unknown. We aimed to assess the safety and efficacy (but not the immunogenicity) of dNS1-RBD against COVID-19. METHODS: We did a multicentre, randomised, double-blind, placebo-controlled, adaptive design, phase 3 trial at 33 centres (private or public hospitals, clinical research centres, or Centre for Disease Control and Prevention) in four countries (Colombia, Philippines, South Africa, and Viet Nam). Men and non-pregnant women (aged ≥18 years) were eligible if they had never been infected with SARS-CoV-2, and if they did not have a SARS-CoV-2 vaccination history at screening or if they had received at least one dose of other SARS-CoV-2 vaccines 6 months or longer before enrolment. Eligible adults were randomly assigned (1:1) to receive two intranasal doses of dNS1-RBD or placebo administered 14 days apart (0·2 mL per dose; 0·1 mL per nasal cavity), with block randomisation via an interactive web-response system, stratified by centre, age group (18-59 years or ≥60 years), and SARS-CoV-2 vaccination history. All participants, investigators, and laboratory staff were masked to treatment allocation. The primary outcomes were safety of dNS1-RBD in the safety population (ie, those who had received at least one dose of dNS1-RBD or placebo) and efficacy against symptomatic SARS-CoV-2 infection confirmed by RT-PCR occurring 15 days or longer after the second dose in the per-protocol population (ie, those who received two doses, were followed up for 15 days or longer after the second dose, and had no major protocol deviations). The success criterion was predefined as vaccine efficacy of more than 30%. This trial is registered with the Chinese Clinical Trial Registry (ChiCTR2100051391) and is completed. FINDINGS: Between Dec 16, 2021, and May 31, 2022, 41 620 participants were screened for eligibility and 31 038 participants were enrolled and randomly assigned (15 517 in the vaccine group and 15 521 in the placebo group). 30 990 participants who received at least one dose (15 496 vaccine and 15 494 placebo) were included in the safety analysis. The results showed a favourable safety profile, with the most common local adverse reaction being rhinorrhoea (578 [3·7%] of 15 500 vaccine recipients and 546 [3·5%] of 15 490 placebo recipients) and the most common systemic reaction being headache (829 [5·3%] vaccine recipients and 797 [5·1%] placebo recipients). We found no differences in the incidences of adverse reactions between participants in the vaccine and placebo groups. No vaccination-related serious adverse events or deaths were observed. Among 30 290 participants who received two doses, 25 742 were included in the per-protocol efficacy analysis (12 840 vaccine and 12 902 placebo). The incidence of confirmed symptomatic SARS-CoV-2 infection caused by omicron variants regardless of immunisation history was 1·6% in the vaccine group and 2·3% in the placebo group, resulting in an overall vaccine efficacy of 28·2% (95% CI 3·4-46·6), with a median follow-up duration of 161 days. INTERPRETATION: Although this trial did not meet the predefined efficacy criteria for success, dNS1-RBD was well tolerated and protective against omicron variants, both as a primary immunisation and as a heterologous booster. FUNDING: Beijing Wantai Biological Pharmacy Enterprise, National Science and Technology Major Project, National Natural Science Foundation of China, Fujian Provincial Science and Technology Plan Project, Natural Science Foundation of Fujian Province, Xiamen Science and Technology Plan Special Project, Bill & Melinda Gates Foundation, the Ministry of Education of China, Xiamen University, and Fieldwork Funds of Xiamen University.

Interactions between climate change, urban infrastructure and mobility are driving dengue emergence in Vietnam.

Dengue is expanding globally, but how dengue emergence is shaped locally by interactions between climatic and socio-environmental factors is not well understood. Here, we investigate the drivers of dengue incidence and emergence in Vietnam, through analysing 23 years of district-level case data spanning a period of significant socioeconomic change (1998-2020). We show that urban infrastructure factors (sanitation, water supply, long-term urban growth) predict local spatial patterns of dengue incidence, while human mobility is a more influential driver in subtropical northern regions than the endemic south. Temperature is the dominant factor shaping dengue's distribution and dynamics, and using long-term reanalysis temperature data we show that warming since 1950 has expanded transmission risk throughout Vietnam, and most strongly in current dengue emergence hotspots (e.g., southern central regions, Ha Noi). In contrast, effects of hydrometeorology are complex, multi-scalar and dependent on local context: risk increases under either short-term precipitation excess or long-term drought, but improvements in water supply mitigate drought-associated risks except under extreme conditions. Our findings challenge the assumption that dengue is an urban disease, instead suggesting that incidence peaks in transitional landscapes with intermediate infrastructure provision, and provide evidence that interactions between recent climate change and mobility are contributing to dengue's expansion throughout Vietnam.