rabies vaccine

COVID-19 Vaccine Knowledge, Practice, and Attitudes Among Hemodialysis Patients in Egypt, Kenya, and Cameroon: A Multicenter Study.

Elsayed Enass E, Kotb Khaled M KM, Heiba Ahmed A, Elhussini Manal Shaker MS et al.

Patients receiving hemodialysis (HD) are at increased risk of severe coronavirus disease 2019 (COVID-19) and were prioritized for vaccination, yet vaccine hesitancy remains common. We assessed COVID-19 vaccine knowledge, acceptance, and attitudes among patients receiving HD in Egypt, Kenya, and Cameroon and identified factors associated with vaccine acceptance, prior infection, willingness to receive future doses, and postvaccination complications. Multicenter cross-sectional survey study. Between March 2021 and April 2022, 765 patients receiving maintenance HD and 196 non-dialysis controls were recruited from dialysis centers in Egypt, Kenya, and Cameroon. Sociodemographic characteristics, clinical comorbidities, prior COVID-19, sources of vaccine information, and exposure to vaccinated or infected relatives. COVID-19 vaccine acceptance, willingness to receive future doses, prior infection, and post-vaccination complications. Structured questionnaires assessed knowledge, practices, and attitudes toward COVID-19 vaccination. Multivariable logistic regression identified factors independently associated with study outcomes. Vaccine acceptance was lower among patients receiving HD than nondialysis controls (58.2% vs 96.2%). Fear of side effects was the most common reason for refusal (39.3%). Postvaccination complications were less frequent among patients receiving HD (22.3% vs 44.3%). Hesitancy was more common among women, younger participants, and those with comorbidities or no prior COVID-19. Having vaccinated or previously infected relatives was associated with a greater willingness to receive future doses. Cross-sectional design limits causal inference. Nonprobability sampling and unmatched controls may limit generalizability. COVID-19 cases may have been underreported because of limited testing. COVID-19 vaccine hesitancy among patients receiving HD is driven by fear, misinformation, and sociodemographic factors. Targeted education and improved access to reliable vaccine information may help increase uptake in this population.

A cavity-reduced prefusion RSV F bivalent vaccine elicits durable and protective immunity.

Liu Lijie L, Yan Mengrong M, Liang Ruoxu R, Wu Qingxin Q et al.

Respiratory syncytial virus (RSV) remains a major cause of severe respiratory disease, and stabilization of the prefusion (preF) conformation of the F glycoprotein is central for vaccine development. Here, we report a structure-guided engineering strategy that enhances preF stability by reducing the hydrophobic cavity within the trimeric F protein. Targeted modifications at metastability-associated sites generated RVF-88, a disulfide-free stabilized preF immunogen that preserves key neutralizing epitopes, including antigenic site Ø, while exhibiting improved structural integrity and long-term storage stability. Formulated as an unadjuvanted bivalent vaccine, RVF-88 elicited potent neutralizing antibody responses and durable immune protection lasting up to 5 months in mice. Vaccination also protected both mice and cotton rats against RSV challenge. Structural analyses confirmed the intended cavity-reduction design, revealing a reduced apical hydrophobic cavity volume and surface area while maintaining the prefusion architecture. Together, these findings establish hydrophobic cavity reduction as a rational strategy for stabilizing prefusion RSV F and provide a promising next-generation vaccine candidate with improved stability and immunogenicity for further clinical development.

Immunogenicity and Safety of the 9-valent Human Papillomavirus (HPV) Vaccine Administered as 2-Dose or 3-Dose Regimens in Japanese Boys and Girls Aged 9-15 Years.

Takeuchi Yuzuru Y, Yonekawa Motoharu M, Murata Shinya S, Nakagomi Mariko M et al.

A phase III open-label study evaluated the immunogenicity and safety of the 9-valent human papillomavirus (9vHPV) vaccine in Japanese boys and girls. Japanese boys aged 9-15 years (n = 105) received a 3-dose (Day 1, Month 2, and Month 6) regimen; Japanese boys (n = 104) and girls aged 9-14 years (n = 105) received a 2-dose (Day 1 and Month 6) regimen. Antibody responses to HPV6/11/16/18/31/33/45/52/58 were assessed at Month 7, 18, and 30 using a competitive Luminex immunoassay. Injection-site adverse events (AEs; Days 1 to 5 post-dose), systemic AEs (Days 1 to 15 post-dose), and serious AEs (duration of study) were assessed. At Month 7, for HPV types targeted by the 9vHPV vaccine, seroconversion rates were 100% in all three arms, and in cross-study comparisons with efficacy studies, anti-HPV geometric mean titers in boys were noninferior to those in Japanese men aged 16-26 years, and in girls were noninferior to those in Japanese women aged 16-26 years. Most injection-site AEs were mild to moderate in intensity. No deaths or vaccine-related serious AEs were observed. These results support immunobridging of efficacy findings in Japanese men and women to Japanese boys and girls. The 9vHPV vaccine was generally well tolerated.

Ethical considerations of incentive structures in vaccine acceptance research.

Musrati Mohamed Amer MA, Shenaisheh Salem S, Elemraid Mohamed A MA