Use Of Vaccines Research Articles

Economic and Clinical Benefits of Bivalent Respiratory Syncytial Virus Prefusion F (RSVpreF) Maternal Vaccine for Prevention of RSV in Infants: A Cost-Effectiveness Analysis for Mexico.

Respiratory syncytial virus (RSV) is a leading cause of respiratory infections in children. A novel RSVpreF vaccine for use among pregnant women for the prevention of RSV in infants is expected to be licensed in Mexico. Hence, the clinical and economic burden of RSV among infants in Mexico, with and without a year-round RSVpreF maternal vaccination program, was estimated. A cohort model was developed to project clinical and economic outcomes of RSV from birth to 1 year of age for maternal vaccination and no intervention. Incremental cost-effectiveness ratios were calculated from direct cost outcomes, life years, and quality-adjusted life years (QALYs). The value per dose of the RSVpreF for which the program would be cost-effective was explored. Analyses were conducted from the healthcare system perspective, with direct costs (2024 Mexican Pesos [MXN]) and outcomes discounted at 5% annually; scenario and sensitivity analyses tested the robustness of model settings and inputs. Compared to no intervention, a year-round RSVpreF vaccine administered to 1891 M pregnant women would prevent 15,768 hospitalizations, 5505 emergency department cases, and 5505 physician office visits annually, averting MXN 1754 M in direct medical costs with an increase of 3402 life years or 3666 QALYs. The RSVpreF vaccine would be cost-saving up to MXN 1301/dose and cost-effective up to MXN 2105-MXN 3715/dose under an assumed cost-effectiveness threshold range of 1-3× the gross domestic product (GDP) per capita (MXN 247,310) per QALY gained. Year-round RSVpreF maternal vaccination would substantially reduce RSV's clinical and economic burden among infants in Mexico and likely be a cost-effective program.

Long-Lasting Protection and Dose Optimization of MPXV Polyvalent Mpox mRNA Vaccines Against Lethal Vaccinia Virus Challenge in Mice.

The outbreak of clade II monkeypox virus (MPXV) and the additional outbreak in Central Africa of clade I virus from 2023 have attracted worldwide attention. The development of a scalable and effective vaccine against the ongoing epidemic of mpox is urgently needed. We previously constructed two bivalent MPXV mRNA vaccines, LBA (B6R-A29L) and LAM (A35R-M1R), and a quadrivalent mRNA vaccine, LBAAM (B6R-A35R-A29L-M1R). These vaccines at a 20 µg dose could induce potential MPXV antigen-specific immune responses and provide protection against lethal VACV challenge. Compared with the individual bivalent mRNA vaccines, the two quadrivalent vaccines LBAAM and LBA& LAM displayed superior protective effects. To characterize these vaccines further, we monitored long-term immunity and protection as long as 28 weeks after initial immunization and optimized the immunization dosages to decrease the cost of production for future clinical use. Our results demonstrated that both the bivalent MPXV mRNA vaccine LAM (A35R-M1R) and the two tetravalent vaccines LBAAM and LBA& LAM could elicit long-lasting antigen-specific IgG antibodies as well as neutralizing antibodies against VACV and MPXV. They all provided complete protection against VACV challenge until 28 weeks post prime immunization. Moreover, the immunogenicity and protective efficacy of the two tetravalent vaccines (LBAAM and LBA& LAM) are dose dependent, and even the low-dose (1 µg) vaccine could provide sufficient protection against lethal VACV challenge. These results provide valuable clues for the further production of MPXV mRNA vaccines for use in humans.

Genetic engineering of Salmonella spp. for novel vaccine strategies and therapeutics.

Salmonella enterica is a diverse species that infects both humans and animals. S. enterica subspecies enterica consists of more than 1,500 serovars. Unlike typhoidal Salmonella serovars which are human host-restricted, non-typhoidal Salmonella (NTS) serovars are associated with foodborne illnesses worldwide and are transmitted via the food chain. Additionally, NTS serovars can cause disease in livestock animals causing significant economic losses. Salmonella is a well-studied model organism that is easy to manipulate and evaluate in animal models of infection. Advances in genetic engineering approaches in recent years have led to the development of Salmonella vaccines for both humans and animals. In this review, we focus on current progress of recombinant live-attenuated Salmonella vaccines, their use as a source of antigens for parenteral vaccines, their use as live-vector vaccines to deliver foreign antigens, and their use as therapeutic cancer vaccines in humans. We also describe development of live-attenuated Salmonella vaccines and live-vector vaccines for use in animals.

Cost-Effectiveness of Bivalent Respiratory Syncytial Virus PrefusionF (RSVpreF) Vaccine During Pregnancy for Prevention of Respiratory Syncytial Virus Among Infants in Argentina.

Lower respiratory tract illness (LRTI) caused by respiratory syncytial virus (RSV) is common among young children in Argentina. Use of the currently available prophylactic agent is limited to children aged ≤ 2years with selected high-risk conditions, and thus the majority of infants remain unprotected. We estimated the value-based price (VBP) of a novel RSVpreF vaccine for use among pregnant people for prevention of RSV-LRTI among infants during the first year of life. Clinical outcomes and economic costs of RSV-LRTI during infancy and expected impact of RSVpreF vaccination during pregnancy were projected using a population-based Markov-type cohort model. Model results-estimated on the basis of gestational age at birth, disease/fatality rates, and mother's vaccination status-include total numbers of RSV-LRTI cases, RSV-LRTI-related deaths, and associated costs. Base case analyses (RSVpreF vs. no vaccine) were conducted from the healthcare system perspective. Probabilistic sensitivity analyses (PSA; 1000 replications) were also conducted. Willingness-to-pay (WTP) was $10,636 per quality-adjusted life-year (QALY; i.e., 1 × 2021 gross domestic product [GDP] per capita) in base case analyses and PSA. Costs are reported in USD, estimated on the basis of the June 22, 2023 exchange rate. Use of RSVpreF among 342,110 pregnant persons provided protection to 330,079 infants at birth. In total, RSVpreF prevented 3915 RSV hospitalizations, 6399 RSV cases requiring emergency department care, 6182 RSV cases requiring a physician office visit, and 67 disease-related deaths. Direct costs were projected to be reduced by $5.0million. With 2061 QALYs gained and vaccine administration cost of $1.4million, the VBP of RSVpreF was estimated to be $74.46 per dose. In PSA, mean VBP was $75.02 (95% confidence interval 54.24-97.30). RSVpreF among pregnant persons would significantly reduce the clinical and economic burden of RSV-LRTI among infants in Argentina and would be considered a cost-effective intervention up to a price of approximately $75.

An Evaluation of the Thermotolerance of Various Formulations of Freeze-Dried and Reconstituted Peste des Petits Ruminant Vaccines.

Peste des Petits Ruminants (PPR) disease is widely distributed in Africa. Live attenuated PPR vaccines are produced using approved Nigeria 75/1 and Sungri/96 strains by the World Organisation of Animal Health (WOAH) to control the disease. These PPR vaccines are very efficacious; however, the main challenge is the maintaining of the cold chain during vaccine distribution and delivery. This study evaluated the thermotolerance of freeze-dried and reconstituted PPR Nigeria 75/1 vaccines from vaccine manufacturers using eight stabilizer formulations (lactalbumin hydrolysate and sucrose, sucrose and peptone, Weybridge medium, trehalose, Lactose and N-Z Amine, lactalbumin hydrolysate, sucrose and L glutamine, skimmed milk, and lactalbumin hydrolysate, maltose and gelatine). Aliquots of the reconstituted PPR vaccine batches were titrated after 2, 4, and 6 h of storage at 4 °C and 40 °C. The PPR vaccines were also titrated after storage at 40 °C and 45 °C for 3 and 5 days. The results showed that reconstituted PPR vaccine stabilized with lactalbumin hydrolysate-sucrose promoted tolerance at 40 °C for 6 h. It was also noted that all reconstituted PPR vaccine formulations except the formulation stabilized with lactalbumin hydrolysate-maltose-gelatine maintained the titre above a 102.5 TCID50/dose after 4 h of storage at 4 °C. Furthermore, the results showed that the PPR vaccine formulation containing lactalbumin hydrolysate sucrose was as the only one that maintained the titres above 102.5 TCID50/dose after storage at 45 °C for 5 days, with a titre loss of 100.95 TCID50/dose. Therefore, vaccine manufacturers producing PPR vaccines for use in tropical field regions could preferably use lactalbumin hydrolysate-sucrose stabilizer in vaccine formulation.

Vaccines for Use in Special Populations: Immunocompromised Hosts.

Vaccines for Use in Special Populations: Immunocompromised Hosts.

Nurses’ Knowledge and Practices on Influenza Vaccination for Pregnant Women

Influenza poses significant health risks to pregnant women, leading to increased morbidity and mortality rates compared to the general population. Despite the proven efficacy of the influenza vaccine in mitigating these risks, vaccination rates among pregnant women remain suboptimal. This study examines nurses' knowledge and attitudes regarding influenza vaccination for pregnant women within the AL-Zubair primary health sector in Basrah, Iraq, addressing the gap in understanding healthcare providers' roles in promoting vaccination. Prior research has highlighted the need for enhanced education and communication strategies among healthcare workers to improve vaccination uptake, yet specific data on nurses' knowledge in this context are limited. The study aims to assess nurses' knowledge, attitudes, and practices regarding influenza vaccination for pregnant women. Among the 88 surveyed nurses, a majority demonstrated adequate knowledge and favorable attitudes towards vaccination, with significant gaps in awareness regarding the consequences of influenza for newborns. Notably, 51.1% acknowledged the vaccine's utility in protecting pregnant women. This research provides crucial insights into the educational needs of nurses, which are essential for fostering effective patient education strategies. The findings underscore the importance of targeted educational interventions to enhance nurses' understanding of influenza vaccination, ultimately aiming to improve vaccination rates among pregnant women and reduce associated health risks.

Development of novel multi-protein chimeric immunogens that protect against infection with the Lyme disease agent, Borreliella burgdorferi.

Lyme disease is the most common tick-borne disease in North America. A vaccine for use in humans is not available. Here, we detail the development of two chimeric vaccine antigens, BAF and Chv2M. BAF elicits Abs that target proteins and protein variants produced by Borreliella species in ticks (OspB and OspA) and mammals (FtlA/B). OspB serves as the backbone structure for the BAF chimeric. Two OspA221-240 epitope-containing domain (ECD) variants (#A1 and #A15) were inserted into a loop in OspB. The N-terminal region of the FtlA protein was joined to the C-terminus of the chimeric. The second chimeric, Chv2M, consists of L5 (loop 5) and H5 (helix 5) ECDs derived from diverse OspC proteins. Borreliella species produce OspC upon exposure to the bloodmeal and during early infection in mammals. Here, we demonstrate that BAF and Chv2M are potent immunogens that elicit Abs that bind to each component protein (FtlA, FtlB, OspB, and multiple OspA and OspC variants). Anti-BAF and anti-Chv2M Abs kill Borreliella burgdorferi strains through Ab-mediated complement-dependent and complement-independent mechanisms. Eighty percent (32/40) of mice that received a three-dose vaccine regimen were protected from infection with B. burgdorferi B31. Efficacy increased to 90% (18/20) when the amount of Chv2M was increased in the third vaccine dose. Readouts for infection were flaB PCR and seroconversion to VlsE. This study establishes proof of principle for a chimeric immunogen vaccine formulation that elicits Abs to multiple targets on the B. burgdorferi cell surface produced during tick and mammalian stages of the enzootic cycle.IMPORTANCELyme disease is a growing public health threat across parts of the Northern Hemisphere. Regions that can support sustained tick populations are expanding, and the incidence of tick-borne diseases is increasing. In light of the increasing risk of Lyme disease, effective preventive strategies are needed. Most vaccine development efforts have focused on outer surface protein A, a Borreliella burgdorferi protein produced only in ticks. Herein, we describe the development of a novel vaccine formulation consisting of two multivalent chimeric proteins that are immunogenic and elicit antibodies with bactericidal activity that target several cell surface proteins produced by the Lyme disease spirochetes in feeding ticks and mammals. In a broader sense, this study advances efforts to develop custom-designed vaccinogens comprised of epitope-containing domains from multiple proteins.

Strategies and Techniques for Enhancing Fish Health and Averting Disease Outbreaks in Aquaculture Settings through the Use of Vaccination: A Review

The fastest–growing animal food-producing agricultural sector in the world is aquaculture, which accounts for almost half of the world’s food fish production.However, the expansion of high-density fish populations also brings forth a challenge–the rapid transmission and spread of infectious agents including several viral, bacterial, and parasitic diseases. Expansion and successful development of sustainable aquaculture practice and increasing production largely depends upon the prevention and control of outbreaks of several emerging and re-emerging infectious diseases which can result in economic loss, food safety hazards, and environmental hazards. Vaccination strategies have become highly effective and economical in protecting the health of fish and other aquaculture organisms from various infectious diseases such as edwardsiellosis, motile aeromonas septicemia (MAS), Tilapia Lake Virus (TiLV) disease, infectious salmon anemia (ISA), vibriosis, and white spot disease etc. An ideal vaccine is expected to be safe, effective, economical, and easily administered. Most of the available fish vaccines are empirically designed vaccines based on inactivated or live attenuated bacterin vaccines. Novel advances in the fields of immunology, biotechnology, and molecular biology have led to the development in designing novel and effective fish vaccines and the improvement of the existing vaccines to provide sufficient immune protection against diseases. This review investigates the currently available fish vaccines for use in finfish aquaculture against different infectious diseases different mode of vaccine administration with addressing pros and cons in detail. The information was collected from different secondary sources, and then compiled systematically.

Economic Evaluation of Expanding HPV Vaccination Programs for Boys: A Systematic Review

Background: Human papillomavirus is responsible for almost all cases of cervical and non-cervical cancers. Various treatments have been carried out, but they have not been effective enough in reducing the burden. The U.S. Food and Drug Administration has approved three HPV vaccines for use. Since its recommendation in 2006, HPV infections have significantly decreased by 88% among teen girls and 81% among young adult women. Additionally, research has indicated that HPV vaccine is cost-effective in preventing both cervical and non-cervical cancers. The primary target group of HPV vaccination is girls aged 9-14, but some countries are starting to expand their programs according to the WHO recommendation for secondary targets: boys and adult women. This study gave updated information regarding the expansion of HPV vaccination programs for boys. Objective: To systematically review the health economic studies to evaluate the cost-effectiveness of expanding HPV vaccination program for including boys to prevent HPV-related cancer. Method: An electronic literature search was performed on two databases (Pubmed and ScienceDirect) to identify studies published from 2013 to 2023 in English and Indonesian. Three search strategies were used, including the terms «economic evaluation», «HPV», and «boys». The screening and selection of the literature was performed according to the PRISMA statement. Results: A total of 306 articles were identified. Only 26 of them were deemed relevant. This research compiled studies from countries with varying economic levels on the expansion of vaccination programs in boys to prevent or reduce cervical, anogenital, and HNC cancers. All the studies used a modeling approach to estimate the number of cases averted and the health care costs. Sixteen studies found that it was cost-effective to expand HPV vaccination programs to include boys. The ICER values were found to be sensitive to the vaccine price, duration of protection, and vaccination coverage. Conclusion: Expanding HPV vaccination to boys is considered a cost-effective solution for preventing HPV-related cancers, based on studies conducted in many countries. It is recommended to conduct an economic evaluation to estimate the cost-effectiveness of HPV vaccination as a prevention method for HPV-related cancers in low and middle-income countries like Indonesia. To begin the study, it is suggested to expand the HPV vaccination target to boys with a lower-priced vaccine and increased vaccination coverage.

Recommendations for Prevention and Control of Influenza in Children, 2024-2025: Policy Statement.

This statement updates the recommendations of the American Academy of Pediatrics for the routine use of influenza vaccines and antiviral medications in the prevention and treatment of influenza in children during the 2024-2025 influenza season. A detailed review of the evidence supporting these recommendations is published in the accompanying technical report (www.pediatrics.org/cgi/doi/10.1542/peds.2024-068508). The American Academy of Pediatrics recommends annual influenza vaccination of all children without medical contraindications starting at 6 months of age. Children are at risk for hospitalization and death from influenza. Influenza vaccination is an important strategy for protecting children and the broader community as well as reducing the overall burden of respiratory illnesses when other viruses are cocirculating. Any licensed influenza vaccine appropriate for age and health status can be administered, ideally as soon as possible in the season, without preference for one product or formulation over another. All licensed influenza vaccines for use in the United States are trivalent for the 2024-2025 influenza season. Antiviral treatment of influenza is recommended for children with suspected (eg, influenza-like illness [fever with either cough or sore throat]) or confirmed influenza who are hospitalized or have severe or progressive disease or have underlying conditions that increase their risk of complications of influenza, regardless of duration of illness. Antiviral treatment should be initiated as soon as possible. Antiviral treatment may be considered in the outpatient setting for symptomatic children who are not at high risk for influenza complications with suspected or confirmed influenza disease, if treatment can be initiated within 48 hours of illness onset. Antiviral treatment may also be considered for children with suspected or confirmed influenza disease whose siblings or household contacts either are younger than 6 months or have a high-risk condition that predisposes them to complications of influenza. Antiviral chemoprophylaxis is recommended for the prevention of influenza virus infection as an adjunct to vaccination in certain individuals, especially exposed children who are asymptomatic and are at high risk for influenza complications but have not yet been immunized or those who are not expected to mount an effective immune response.

The Rift Valley fever (RVF) vaccine candidate 40Fp8 shows an extreme attenuation in IFNARKO mice following intranasal inoculation.

Rift Valley fever (RVF) is an important zoonotic viral disease affecting several species of domestic and wild ruminants, causing major economic losses and dozens of human deaths in various geographical areas of Africa, where it is endemic. Although it is not present in Europe, there is a risk of its introduction and spread linked to globalisation and climate change. At present, the only measure that could help to prevent the disease is vaccination of flocks in areas at risk of RVF. Available live attenuated vaccines are an effective means of controlling the disease, but their use is often questioned due to residual virulence, particularly in susceptible hosts such as pregnant sheep. On the other hand, no vaccine is currently licensed for use in humans. The development of safe and effective vaccines is therefore a major area of research. In previous studies, we selected under selective mutagenic pressure a highly attenuated RVFV 56/74 virus variant called 40Fp8. This virus showed an extremely attenuated phenotype in both wild-type and immunodeficient A129 (IFNARKO) mice, yet was still able to induce protective immunity after a single inoculation, thus supporting its use as a safe, live attenuated vaccine. To further investigate its safety, in this work we have analysed the attenuation level of 40Fp8 in immunosuppressed mice (A129) when administered by the intranasal route, and compared it with other attenuated RVF viruses that are the basis of vaccines in use or in development. Our results show that 40Fp8 has a much higher attenuated level than these other viruses and confirm its potential as a candidate for safe RVF vaccine development.

Antibody-mediated immunological memory correlates with long-term Lyme veterinary vaccine protection in mice

Lyme disease, caused by the bacterium Borrelia burgdorferi, is the most common tick-borne illness in the United States. Despite the rise in Lyme disease incidence, there is no vaccine against B. burgdorferi approved for human use. Little is known about the immune correlates of protection needed to prevent Lyme disease. In this work, a mouse model was used to characterize the immune response and compare the protection provided by two USDA-approved vaccines for use in canines: Duramune (bacterin vaccine) and Vanguard crLyme (subunit vaccine composed of two outer surface proteins, OspA and OspC). C3H/HeNCrl mice were immunized with two doses of either Duramune or Vanguard, and immune responses and protection against B. burgdorferi were assessed in short (35 days) and long-term (120 days) studies. Flow cytometry, ELISPOT detection of antibody-producing cells, and antibody affinity studies were performed to identify correlates of vaccine-mediated protection. Both vaccines induced humoral responses, with high IgG titers against B. burgdorferi. However, the levels of anti-B. burgdorferi antibodies decayed over time in Vanguard-vaccinated mice. While both vaccines triggered the production of antibodies against both OspA and OspC, antibody levels against these proteins were also lower in Vanguard-vaccinated mice 120 days post-vaccination. Both vaccines only provided partial protection against B. burgdorferi at the dose used in this model. The protection provided by Duramune was superior to Vanguard 120 days post-vaccination, and was characterized by higher antibody titers, higher abundance of long-lived plasma cells, and higher avidity antibodies than Vanguard. Overall, these studies provide insights into the importance of the humoral memory response to veterinary vaccines against Lyme disease and will help inform the development of future human vaccines.

Simultaneous construction strategy using two types of fluorescent markers for HVT vector vaccine against infectious bursal disease and H9N2 avian influenza virus by NHEJ-CRISPR/Cas9.

Recently, herpesvirus of turkeys (HVT), which was initially employed as a vaccine against Marek's disease (MD), has been shown to be a highly effective viral vector for producing recombinant vaccines that can simultaneously express the protective antigens of multiple poultry diseases. Prior to the development of commercial HVT-vectored dual-insert vaccines, the majority of HVT-vectored vaccines in use only contained a single foreign gene and were often generated using time-consuming and inefficient traditional recombination methods. The development of multivalent HVT-vectored vaccines that induce simultaneous protection against several avian diseases is of great value. In particular, efficacy interference between individual recombinant HVT vaccines can be avoided. Herein, we demonstrated the use of CRISPR/Cas9 gene editing technology for the insertion of an IBDV (G2d) VP2 expression cassette into the UL45/46 region of the recombinant rHVT-HA viral genome to generate the dual insert rHVT-VP2-HA recombinant vaccine. The efficacy of this recombinant virus was also evaluated in specific pathogen-free (SPF) chickens. PCR and sequencing results showed that the recombinant virus rHVT-VP2-HA was successfully constructed. Vaccination with rHVT-VP2-HA produced high levels of specific antibodies against IBDV (G2d) and H9N2/Y280. rHVT-VP2-HA can provide 100% protection against challenges with IBDV (G2d) and H9N2/Y280. These results demonstrate that rHVT-VP2-HA is a safe and highly efficacious vaccine for the simultaneous control of IBDV (G2d) and H9N2/Y280.

Molecular Detection and Characterization of Newcastle Disease Virus from Chickens in Mid-Rift Valley and Central Part of Ethiopia.

Newcastle disease (ND) is a highly infectious poultry disease that causes major economic losses worldwide. The disease is caused by Newcastle Disease Virus (NDV) and early detection and identification of the viral strain is essential. Having knowledge of the NDV strain genotype that circulates in some regions would help in designing an effective vaccine to control the disease. In this regard, there is little information on NDV strain in chickens in mid Rift Valley and the central part of Ethiopia. Therefore, the purpose of this study was to detect and characterize NDV strain genotype from chickens in mid-Rift Valley and the central part of Ethiopia and test whether this NDV strain genotype matches the vaccine strain currently used in the study area. A total of 98 samples: 78 (tracheal and cloacal) swabs from chicken pools of five and 20 tissue samples were collected. To detect NDV strain, conserved region of the virus Matrix (M) gene was amplified by qRT-PCR. To characterize NDV strain genotypes, M-gene positive samples were specifically re-amplified by conventional PCR targeting the Fusion (F) gene region and sequenced by Sanger method. 13.26% of tested samples were positive for NDV strain in the study area with statistically significant difference (P<0.05) among the study sites. Further characterization of the F genes from NDV strain isolates by phylogenetic analysis indicated that one field isolate clustered with genotype VII whereas three of the isolates clustered to genotype I, II, and III. The isolate of the current NDV strain vaccine in use in the study area clustered with genotype II. The current study indicates the existence of different NDV strain genotype from that of the vaccine strain currently used. Even though large-scale characterization of several isolates is required at national level, the current study laid baseline information for the existence of variations between field NDV strain genotype and vaccine strain currently used against ND in the country.

Evaluation of the safety and efficacy of the novel Mycoplasma gallisepticum vaccine, Vaxsafe MG304, after spray-vaccination of 1-day-old specific pathogen-free chicks

Mycoplasma gallisepticum causes chronic respiratory disease in poultry. A novel vaccine, Vaxsafe MG304 (the ts-304 strain), has greater protective efficacy in chickens than the Vaxsafe MG (strain ts-11) vaccine when delivered by eye drop at 3 weeks of age. Applying this vaccine in the hatchery to 1-day-old birds, using mass administration methods, would improve animal welfare and reduce labour costs associated with handling individual birds. This study assessed the protection provided by vaccination with Vaxsafe MG304 after administration to 1-day-old chicks. Chicks were administered a single dose of the vaccine to assess the efficacy of either a high dose (107.0 colour changing units, CCU) or a low dose (105.7 CCU) after eye drop or spray (in water or gel) administration against experimental challenge with virulent M. gallisepticum strain Ap3AS at 7 weeks of age. The vaccine was able to colonise the palatine cleft of chicks after vaccination by eye drop (at both doses) or by spray (in water or gel) (at the high dose). The high dose of vaccine, when delivered by eye drop or spray, was shown to be safe and induced a serological response and protective immunity (as measured by tracheal mucosal thickness and air sac lesion scores) against challenge. Vaccination of 1-day-old chicks with Vaxsafe MG304 by eye drop induced protective immunity equivalent to vaccination at 3 weeks of age. Vaxsafe MG304 was also protective when applied by both coarse- and gel spray methods at the higher dose and is therefore a suitable live attenuated vaccine for use in 1-day-old chicks.

Protective efficacy and safety of radiation-attenuated and chemo-attenuated Plasmodium Falciparum sporozoite vaccines against controlled and natural malaria infection: a systematic review and meta-analysis of randomized controlled trials.

Despite the significant burden of Plasmodium falciparum (Pf) malaria and the licensure of two vaccines for use in infants and young children that are partially effective in preventing clinical malaria caused by Pf, a highly effective vaccine against Pf infection is still lacking. Live attenuated vaccines using Pf sporozoites as the immunogen (PfSPZ Vaccines) hold promise for addressing this gap. Here we review the safety and efficacy of two of the most promising PfSPZ approaches: PfSPZ Vaccine (radiation attenuated PfSPZ) and PfSPZ-CVac (chemo-attenuated PfSPZ). We conducted a systematic review and meta-analysis by searching PubMed, EMBASE, SCOPUS, CENTRAL, and WOS until 22nd December 2021. We included randomized controlled trials (RCTs) of these two vaccine approaches that measured protection against parasitaemia following controlled human malaria infection (CHMI) in malaria-naive and malaria-exposed adults or following exposure to naturally transmitted Pf malaria in African adults and children (primary outcome) and that also measured the incidence of solicited and unsolicited adverse events as indicators of safety and tolerability after vaccination (secondary outcome). We included randomized controlled trials (RCTs) that measured the detected parasitaemia after vaccination (primary outcome) and the incidence of various solicited and unsolicited adverse events (secondary outcome). The quality of the included RCTs using the Cochrane ROB 1 tool and the quality of evidence using the GRADE system were evaluated. We pooled dichotomous data using the risk ratio (RR) for development of parasitemia in vaccinees relative to controls as a measure of vaccine efficacy (VE), including the corresponding confidence interval (CI). This study was registered with PROSPERO (CRD42022308057). We included 19 RCTs. Pooled RR favoured PfSPZ Vaccine (RR: 0.65 with 95% CI [0.53, 0.79], P = 0.0001) and PfSPZ-table (RR: 0.42 with 95% CI [0.27, 0.67], P = 0.0002) for preventing parasitaemia, relative to normal saline placebo. Pooled RR showed no difference between PfSPZ Vaccine and the control in the occurrence of any solicited adverse event (RR: 1.00 with 95% CI [0.82, 1.23], P = 0.98), any local solicited adverse events (RR: 0.73 with 95% CI [0.49, 1.08], P = 0.11), any systemic solicited adverse events (RR: 0.94 with 95% CI [0.75, 1.17], P = 0.58), and any unsolicited adverse event (RR: 0.93 with 95% CI [0.78, 1.10], P = 0.37). PfSPZ and PfSPZ-CVacs showed comparable efficacy. Therefore, they can introduce a promising strategy for malaria prophylaxis, but more large-scale field trials are required to sustain efficacy and yield clinically applicable findings.

Pharmacovigilance in Brazil: The Government Monitoring of Adverse Events Reported from COVID-19 Vaccine—A Narrative Review

Background: Is pharmacovigilance at a moment of prominence for science, and in relation to governments’ responsibilities towards their nations, as the new coronavirus pandemic has surprised everyone in a negative and lethal way? Objective: Evaluate pharmacovigilance as a resource for controlling and understanding adverse events caused by vaccines in use. Methods: This is a narrative review of the literature. Scientific articles available in databases, government bulletins and similar bodies were used. The search was carried out using the descriptors: “Pharmacovigilance AND COVID-19 in Brazil”, “Vaccine Development AND COVID-19”, “Vaccination Hesitancy AND COVID-19”, “Public Health Surveillance AND COVID-19”. The period from May 2021 to June 2022 was covered. Results: The occurrence of some adverse events was observed, including cases of allergy, myocarditis and rheumatoid arthritis. It is important to highlight that these adverse events were identified as rare, occurring in a small percentage of the vaccinated population. Despite these adverse events, the benefits of vaccines proved to be essential for controlling the pandemic. Conclusions: The information presented highlights the importance of pharmacovigilance to continuously monitor and evaluate the safety of vaccines, identifying any potential adverse events early. This balance between risk and benefit emphasizes the need for a careful and informed approach when making decisions about vaccination policies, prioritizing public health and population safety.

Immunization in women's lives: present and future.

•The negative impact of infectious diseases and their immunoprevention during the different stages of a woman's life requires a broad approach including adolescence, adulthood, pregnancy and the postmenopausal phase. •Immunization of pregnant women should be a priority for the protection of the maternal-fetal dyad, especially in regions with high rates of infections preventable by immunization. •Brazil has one of the most comprehensive vaccination programs in the world - the National Immunization Program (Programa Nacional de Imunizações, PNI) - that serves all age groups: newborns, children, adolescents, adults, pregnant women and older adults, as well as groups with special needs, such as adolescents, pregnant and older adult women. •However, vaccination coverage remains below ideal for all available vaccines, especially among adolescents and pregnant women, and Febrasgo is committed to collaborating with the PNI to combat vaccine hesitancy. •The gynecologist/obstetrician is the reference physician for women, therefore the access to information and updates regarding all vaccines recommended for their patients is extremely important for this professional, aiming at the greatest possible protection. •The objective of this Febrasgo Position Statement is to bring an update to women's vaccination schedule, covering some vaccines that are available, including new approved vaccines and those in the commercialization phase. •This work is a compilation of the First Febrasgo Scientific Immunization Forum held in the city of São Paulo in October 2023 with the objective to update recommendations for vaccines in use and new innovative vaccines soon to be available.

Genetic characterization of group A rotavirus in children with acute gastroenteritis in Kericho County Referral Hospital, Kenya.

approximately over 80% of mortalities due to rotavirus occur in countries that have limited resources, especially in sub-Saharan Africa and South Asia. The study was intended to determine the genetic characteristics of rotavirus A in children exhibiting gastroenteritis at Kericho County Referral Hospital. the study design was cross-sectional. Consecutive sampling was engaged obtaining a sample size of 200 stool samples. Genetic characterization of group A rotavirus strains was done using Enzyme-Linked Immunosorbent Assay. Positive samples underwent Sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Afterwards viewing of the RNA double strands of the rotavirus genome in gels was done using Silver Nitrate. The positive samples underwent RT-PCR amplification followed by sequencing on the pieces of the VP7 or VP4 gene obtained. one hundred and six (53%) samples from males and 94 (47%) from females. Twenty-three samples were positive hence a prevalence of 11.5%. The most affected demographics were children of guardians with secondary school education (51%). The most affected social economic status was housewives (46.5%). The most affected age was 21-30 months at 26.5%. Long electropherotypes were in 22 samples (96%). The G3 genotype of rotavirus A was prevalent 16/23 (69.57%). rotavirus prevalence was 11.5%. The G3 genotype was the most prevalent in circulation. The occurrence of non-typable strains indicated that the strains may be diversified emphasizing the need to include emerging strains within the vaccines in use. Hence the need to continuously monitor the effects in older children.