Protective Effect Of Vaccine Research Articles

The number of COVID-19 clusters in healthcare and elderly care facilities averted by vaccination of healthcare workers in Japan, February-June 2021.

In Japan, a prioritized COVID-19 vaccination program using Pfizer/BioNTech messenger RNA (mRNA) vaccine among healthcare workers commenced on February 17, 2021. As vaccination coverage increases, clusters in healthcare and elderly care facilities including hospitals and nursing homes are expected to be reduced. The present study aimed to explicitly estimate the protective effect of vaccination in reducing cluster incidence in those facilities. A mathematical model was formulated using three pieces of information: (1) the incidence of clusters in facilities from October 26, 2020 to June 27, 2021; (2) the incidence of confirmed COVID-19 cases during the same period; and (3) vaccine doses among healthcare workers from February 17 to June 27, 2021, extracted from the national Vaccination System database. We found that the estimated proportion at risk in healthcare and elderly care facilities declined substantially as the vaccination coverage among healthcare workers increased; the greater risk reduction was observed in healthcare facilities, at 0.10 (95% confidence interval (CI): 0.04-0.16) times that in the pre-vaccination period, while that in elderly care facilities was 0.34 (95% CI: 0.24-0.43) times that in the earlier period. The averted numbers of clusters in healthcare facilities and elderly care facilities were estimated to be 247 (95% CI: 210-301) and 279 (95% CI: 218-354), respectively. Prioritized vaccination among healthcare workers had a marked impact on preventing the incidence of clusters in facilities.

Dynamics of specific antibodies in COVID-19 patients after recovery.

Abstract The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented global public health crisis. The objectives of this study were to analyse the dynamic trend in specific antibodies in the serum of patients infected with SARS-CoV-2 within 12 months after recovery and to make a preliminary assessment of the protective effect of vaccination. Eighty-seven patients with confirmed COVID-19 who were admitted to our hospital from January to February 2020 were followed after recovery. Three-millilitre blood samples were collected for specific antibody detection at four time points: 1, 6 and 12 months after recovery and 1 month after vaccination. The changes in specific immunoglobulin G (IgG) antibody and total antibody levels over 12 months were analysed. Moreover, an independent comparison of the neutralising antibody levels of patients after vaccination with those of healthy medical staff after vaccination was performed to compare the inhibition rates of the neutralising antibody to the virus. No statistically significant difference in the sex distribution between groups was observed (P > 0.05). Older patients had a greater risk of developing severe and critical COVID-19 (P < 0.05). The percentages of subjects positive for IgG antibodies at 1, 6 and 12 months after recovery were 88.5%, 75.9% and 50.6%, respectively. The rate of IgG antibody conversion from positive to negative was not uniform across time points: the change was slow in the first 6 months but increased significantly in the last 6 months (P < 0.05). The positive rate of critically ill patients in the first 6 months was 100.0%. The trend over time in total antibody levels was similar to that of IgG antibody levels. Over 12 months, the sample/cut off value of total antibodies continued to decrease, while that of different disease severities was significantly different (P < 0.05). After vaccine administration, the total antibody level exceeded the detection level in the first month, which was independent of disease severity (P > 0.05). Significant differences were observed in the inhibition rate of the neutralising antibody against the virus in the disease group and the control group (P < 0.05). IgG antibody produced by patients naturally infected with SARS-CoV-2 has a duration of no less than 1 year, and the change trend graph of total antibody levels was the same as that of IgG antibody levels. Under vaccine stimulation, the positive rate of IgG antibody was as high as 100%, and the total antibody concentration reached the highest level, which was independent of disease severity. Neutralising antibodies following vaccination in patients who recovered from COVID-19 had a higher inhibition rate against SARS-CoV-2 than those of vaccinated healthy controls, indicating that these COVID-19 patients had a lower risk of reinfection and were better protected.

β-Glucans Could Be Adjuvants for SARS-CoV-2 Virus Vaccines (COVID-19).

Waiting for an effective treatment against the SARS-CoV-2 virus (the cause of COVID-19), the current alternatives include prevention and the use of vaccines. At the moment, vaccination is the most effective strategy in the fight against pandemic. Vaccines can be administered with different natural biological products (adjuvants) with immunomodulating properties. Adjuvants can be taken orally, complementing vaccine action. Adjuvant compounds could play a key role in alleviating the symptoms of the disease, as well as in enhancing vaccine action. Adjuvants also contribute to an effective immune response and can enhance the protective effect of vaccines in immunocompromised individuals such as the elderly. Adjuvants must not produce adverse effects, toxicity, or any other symptoms that could alter immune system function. Vaccine adjuvants are substances of wide varying chemical structure that are used to boost the immune response against a simultaneously administered antigen. Glucans could work as adjuvants due to their immunomodulatory biological activity. In this respect, β-(1,3)-(1,6) glucans are considered the most effective and safe according to the list issued by the European Commission. Only glucans with a β-(1,3) bond linked to a β-(1,6) are considered modulators of certain biological responses. The aim of this review is to present the possible effects of β-glucans as adjuvants in the efficacy of vaccines against SARS-CoV-2 virus.

Progress in research of epidemiologic feature and control of SARS-CoV-2 Delta variant

SARS-CoV-2 Delta variant has the characteristics of stronger infectivity, higher viral load, and shorter incubation period, posing new challenges to the prevention and control of COVID-19 pandemic. SARS-CoV-2 Delta variant was first discovered in India, then quickly spread in many countries and has gradually become one of the main epidemic strains worldwide. Local epidemics caused by SARS-CoV-2 Delta variant also occurred in several provinces in China. This article summarizes the progress in research of etiological characteristics, transmission characteristics or possible mechanism and epidemiological characteristics of SARS-CoV-2 Delta variant, and the protective effects of vaccines and control measures against SARS-CoV-2 Delta variant in order to provide references for the effective prevention and control of COVID-19 epidemic caused by SARS-CoV-2 Delta variant.

A Systematic Review of the Protective Effect of Prior SARS-CoV-2 Infection on Repeat Infection.

We systematically reviewed studies to estimate the risk of SARS-CoV-2 reinfection among those previously infected with SARS-CoV-2. For this systematic review, we searched scientific publications on PubMed and MedRxiv, a pre-print server, through August 18, 2021. Eligible studies were retrieved on August 18, 2021. The following search term was used on PubMed: (((“Cohort Studies”[Majr]) AND (“COVID-19”[Mesh] OR “SARS-CoV-2”[Mesh])) OR “Reinfection”[Majr]) OR “Reinfection”[Mesh]. The following search term was used on MedRxiv: “Cohort Studies” AND “COVID-19” OR “SARS-CoV-2” AND “Reinfection”. The search terms were broad to encompass all applicable studies. There were no restrictions on the date of publication. Studies that did not describe cohorts with estimates of the risk of SARS-CoV-2 reinfection among those with previous infection were excluded. Studies that included vaccinated participants were either excluded or limited to sub-groups of non-vaccinated individuals. To identify relevant studies with appropriate control groups, we developed the following criteria for studies to be included in the systematic analysis: (1) baseline polymerase chain reaction (PCR) testing, (2) a uninfected comparison group, (3) longitudinal follow-up, (4) a cohort of human participants, i.e. not a case report or case series, and (5) outcome determined by PCR. The review was conducted following PRISMA guidelines. We assessed for selection, information, and analysis bias, per PRISMA guidelines. We identified 1,392 reports. Of those, 10 studies were eligible for our systematic review. The weighted average risk reduction against reinfection was 90.4% with a standard deviation of 7.7% (p-value: <0.01). Protection against SARS-CoV-2 reinfection was observed for up to 10 months. Studies had potential information, selection, and analysis biases. The protective effect of prior SARS-CoV-2 infection on re-infection is high and similar to the protective effect of vaccination. More research is needed to characterize the duration of protection and the impact of different SARS-CoV-2 variants.

Vaccination for Respiratory Infections in Patients with Heart Failure.

Bronchopulmonary infections are a major trigger of cardiac decompensation and are frequently associated with hospitalizations in patients with heart failure (HF). Adverse cardiac effects associated with respiratory infections, more specifically Streptococcus pneumoniae and influenza infections, are the consequence of inflammatory processes and thrombotic events. For both influenza and pneumococcal vaccinations, large multicenter randomized clinical trials are needed to evaluate their efficacy in preventing cardiovascular events, especially in HF patients. No study to date has evaluated the protective effect of the COVID-19 vaccine in patients with HF. Different guidelines recommend annual influenza vaccination for patients with established cardiovascular disease and also recommend pneumococcal vaccination in patients with HF. The Heart Failure group of the French Society of Cardiology recently strongly recommended vaccination against COVID-19 in HF patients. Nevertheless, the implementation of vaccination recommendations against respiratory infections in HF patients remains suboptimal. This suggests that a national health policy is needed to improve vaccination coverage, involving not only the general practitioner, but also other health providers, such as cardiologists, nurses, and pharmacists. This review first summarizes the pathophysiology of the interrelationships between inflammation, infection, and HF. Then, we describe the current clinical knowledge concerning the protective effect of vaccines against respiratory diseases (influenza, pneumococcal infection, and COVID-19) in patients with HF and finally we propose how vaccination coverage could be improved in these patients.

COVID-19: epidemiology and mutations : An update

Mutationen von SARS-CoV‑2 können die Ausbreitungsfähigkeit und Infektiosität erhöhen sowie die Schutzwirkung von Antikörpern vermindern, die nach einer Infektion, einer Impfung oder einer Antikörpertherapie vorhanden sind. Die Alpha-Variante (B.1.1.7), die zuerst in Kent/Großbritannien beobachtet wurde, hat zu einer Erhöhung des R‑Werts und damit der Infektiosität um 75 % geführt. Die Wirksamkeit der in Deutschland verfügbaren Impfungen gegen SARS-CoV‑2 scheint durch diese Mutationen jedoch nur geringfügig beeinträchtigt zu sein. Bei der Beta-Variante (B.1.351), die zuerst in Südafrika beschrieben wurde, ist die Fähigkeit von Antikörpern, SARS-CoV‑2 zu neutralisieren, vermindert. Die therapeutisch verwendeten monoklonalen Antikörper Bamlanivimab und Etesivimab sind unwirksam. Der Impfstoff von AstraZeneca hat gegenüber leichten und mittelschweren Erkrankungen durch die Beta-Variante fast keine Schutzwirkung. Die Gamma-Variante (P.1 oder B.1.1.28.1), die zuerst in Brasilien gefunden wurde, ist wahrscheinlich um den Faktor 1,7 bis 2,6 stärker übertragbar als zuvor in Brasilien zirkulierende Virusstämme. Neben der Infektiosität scheint auch das Sterberisiko bei der Gamma-Variante um den Faktor 1,2 bis 1,9 bei Erwachsenen und bei jüngeren Patienten um den Faktor 5 bis 8 erhöht zu sein. Die Delta-Variante (B.1.617), die zuerst in Indien beschrieben wurde, ist inzwischen in den meisten Ländern dominierend. Ihre Infektiosität ist gegenüber der zuvor dominierenden Alpha-Variante um etwa 50 % erhöht, die Schutzwirkung der verfügbaren Impfungen vor symptomatischen Erkrankungen kann vermindert sein (BioNTech: Delta-Variante 88 %, Alpha-Variante 93,7 %; AstraZeneca: Delta-Variante 67 %, Alpha-Variante 74,5 %). Ferner ist der Krankheitsverlauf bei der Delta-Variante oft schwerer als beim Wildtyp. Erkrankungen durch die Delta-Variante verlaufen bei Geimpften leichter als bei Ungeimpften, und tödliche Verläufe sind wesentlich seltener. Eine hohe Impfquote ist unerlässlich, um einer Herdenimmunität möglichst nahezukommen und die Pandemie unter Kontrolle zu bringen. Selbst bei verminderter Schutzwirkung gegenüber leichten und mittelschweren Erkrankungen bieten Impfungen in der Regel einen ausgezeichneten Schutz gegenüber lebensbedrohlichen und tödlichen Krankheitsverläufen.

PEG-modified subunit vaccine encoding dominant epitope to enhance immune response against spring viraemia of carp virus.

Spring viraemia of carp (SVC) caused by spring viraemia of carp virus (SVCV) can infect almost all fish of cyprinids, which bring huge economic losses to aquaculture. Glycoprotein (G), as the most important antigenic determinant protein of SVCV, is widely considered as an effective method against SVCV. In our previous study, we found that G3 (131 aa) is the potential dominant antigen epitope that induces strong immune responses similar to G protein (510 aa). Here, in order to further improve the immune effect, we reported a subunit vaccine (PEG-G3) constructed by PEG-modified dominant epitope protein (G3). The results of serum antibody production, enzyme activities and immune-related genes expression showed that PEG-G3 induces significantly stronger immune protective responses against SVCV than G3. PEG modification significantly increased the serum antibody level of the vaccine, which increased significantly after immunization and reached the peak at 21day post-vaccination. T-AOC and AKP activities in the lowest concentration group (5μg) of PEG-G3 were significantly higher than those in the highest concentration group (20μg) of G3. In PEG-G3 group, the expression of almost all genes increased at least 4 times compared with the control group. After 14-day challenge, the RPS (relative percentage survival) of the highest concentration of PEG-G3 group was 53.6%, while that of G3 group is 38.9%. Therefore, this work shows that PEG modification and dominant epitope screening may be effective methods to improve the immune protective effect of vaccines and to resist the infection of aquatic animal viral diseases.

Factors associated with behavioral intention of free and self-paid severe acute respiratory coronavirus virus 2 (SARS-CoV-2) vaccination based on the social cognitive theory among nurses and doctors in China.

To examine the associations between factors based on the social cognitive theory (SCT) and behavioral intention among doctors and nurses in China toward free and self-paid (600 RMB or US$91) severe acute respiratory coronavirus virus 2 (SARS-CoV-2) vaccination given 80% effectiveness and rare mild side effects. Cross-sectional study. Public hospitals. The study included 362 doctors and 1,702 nurses in major departments of 5 hospitals of 3 Chinese provinces. An anonymous online survey was conducted from October to November 2020, facilitated by hospital administrators through online WeChat/QQ working groups. Data on outcome expectations, self-efficacy, norms, and COVID-19-related work experiences were collected. Multivariate logistic regression models were used for data analyses. The logistic regression analysis showed that physical (eg, protective effect of vaccination) and self-evaluative outcome expectations (eg, anticipated regret), self-efficacy, norms (eg, descriptive norm, subjective norm, professional norm, and moral norm), and job satisfaction were significantly and positively associated with the free and self-paid SARS-CoV-2 vaccination intention outcomes among doctors and nurses, adjusted for background variables. Doctors who had engaged in COVID-19-related work reported higher self-paid vaccination intention. Health promotion is needed to improve the uptake of SARS-CoV-2 vaccination among healthcare workers. Such interventions may consider modifying the identified factors of vaccination intention, including strengthening perceived efficacy, positive feelings about vaccination, the need to avoid future regret, self-efficacy, and social norms. Future studies should examine the actual behavior patterns of SARS-CoV-2 vaccination, and the efficacy of promotion intervention should be tested in randomized controlled studies.

Nonhuman primate to human immunobridging to infer the protective effect of an Ebola virus vaccine candidate

It has been proven challenging to conduct traditional efficacy trials for Ebola virus (EBOV) vaccines. In the absence of efficacy data, immunobridging is an approach to infer the likelihood of a vaccine protective effect, by translating vaccine immunogenicity in humans to a protective effect, using the relationship between vaccine immunogenicity and the desired outcome in a suitable animal model. We here propose to infer the protective effect of the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen with an 8-week interval in humans by immunobridging. Immunogenicity and protective efficacy data were obtained for Ad26.ZEBOV and MVA-BN-Filo vaccine regimens using a fully lethal EBOV Kikwit challenge model in cynomolgus monkeys (nonhuman primates [NHP]). The association between EBOV neutralizing antibodies, glycoprotein (GP)-binding antibodies, and GP-reactive T cells and survival in NHP was assessed by logistic regression analysis. Binding antibodies against the EBOV surface GP were identified as the immune parameter with the strongest correlation to survival post EBOV challenge, and used to infer the predicted protective effect of the vaccine in humans using published data from phase I studies. The human vaccine-elicited EBOV GP-binding antibody levels are in a range associated with significant protection against mortality in NHP. Based on this immunobridging analysis, the EBOV GP-specific-binding antibody levels elicited by the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in humans will likely provide protection against EBOV disease.

Lack of protection against feline immunodeficiency virus infection among domestic cats in New Zealand vaccinated with the Fel-O-Vax® FIV vaccine

Infections with feline immunodeficiency virus (FIV) are common in New Zealand, although the impact of those infections on the health status of the cats remains unclear. Although many cats are vaccinated yearly with a commercial FIV vaccine containing FIV subtypes A and D, the effectiveness of this vaccine in protection against infection with field FIVs is unclear, as a high proportion of New Zealand viruses belong to subtype C. The objective of the study was to compare the frequency of FIV infection among adult FIV-vaccinated and FIV-unvaccinated domestic cats with access to outdoors. Buccal swabs were collected by the participating veterinarians and tested for the presence of FIV provirus by quantitative PCR. Overall, 26/185 (14.0 %) samples were positive for FIV, including 7/82 (8.5 %) samples from FIV-unvaccinated and 19/103 (18.4 %) from FIV-vaccinated cats. There was no protective effect of vaccination on FIV infection among sampled cats (p = 0.05). Partial sequences of the FIV envelope gene from five New Zealand viruses were analysed by the maximum likelihood method. All clustered with other New Zealand FIV sequences from subtypes A (n = 2), C (n = 2) or putative recombinant viruses (n = 1). While the FIV vaccination did not prevent FIV infection among sampled cats, it may have had an impact on transmissibility of the virus or on disease progression. As neither was addressed in the current study, further research is needed to fully assess the potential benefits of FIV vaccination. Considering the frequency of FIV infection in FIV-vaccinated cats, FIV infection status should be monitored not only before the first vaccination, but before each yearly booster.

Single-walled carbon nanotubes enhance the immune protective effect of a bath subunit vaccine for pearl gentian grouper against Iridovirus of Taiwan

Iridovirus of Taiwan (TGIV) has been threatening the grouper farming since 1997, effective prophylaxis method is urgently needed. Subunit vaccine was proved to be useful to against the virus. Bath is the simplest method of vaccination and easy to be administrated without any stress to fish. In this research, we constructed a prokaryotic expression vector of TGIV's major capsid protein (MCP) to acquire the vaccine. Single-walled carbon nanotubes (SWCNTs) were used as the carrier to enhance the protective effect of bath vaccination for juvenile pearl gentian grouper (bath with concentrations of 5, 10, 20 mg/L for 6 h). Virus challenge was done after 28 days. Survival rates were calculated after 14 days. The level of antibody, activities of related enzymes in serums and expression of immune-related genes in kidneys and spleens were test. The results showed that vaccine with SWCNTs as carrier induced a higher level of antibody than that without. In addition, the activities of related enzymes (acid phosphatase, alkaline phosphatase, superoxide dismutase) and the expression of immune-related genes (Mx1, IgM, TNFαF, Lysozyme, CC chemokine 1, IL1-β, IL-8) had a significantly increase. What's more, higher survival rates (42.10%, 77.77%, 89.47%) were provided by vaccine with SWCNTs than vaccine without SWCNTs (29.41%, 38.09%, 43.75%). This study suggests that the protective effect of vaccine that against TGIV with the method of bath vaccination could be enhanced by SWCNTs and SWCNTs could be a potential carrier for other subunit vaccines.

Integrating fish models in tuberculosis vaccine development.

ABSTRACTTuberculosis is a chronic infection by Mycobacterium tuberculosis that results in over 1.5 million deaths worldwide each year. Currently, there is only one vaccine against tuberculosis, the Bacillus Calmette–Guérin (BCG) vaccine. Despite widespread vaccination programmes, over 10 million new M. tuberculosis infections are diagnosed yearly, with almost half a million cases caused by antibiotic-resistant strains. Novel vaccination strategies concentrate mainly on replacing BCG or boosting its efficacy and depend on animal models that accurately recapitulate the human disease. However, efforts to produce new vaccines against an M. tuberculosis infection have encountered several challenges, including the complexity of M. tuberculosis pathogenesis and limited knowledge of the protective immune responses. The preclinical evaluation of novel tuberculosis vaccine candidates is also hampered by the lack of an appropriate animal model that could accurately predict the protective effect of vaccines in humans. Here, we review the role of zebrafish (Danio rerio) and other fish models in the development of novel vaccines against tuberculosis and discuss how these models complement the more traditional mammalian models of tuberculosis.

Blackleg in inadequately immunized calves and their recovery following antibiotic therapy.

There is consensus regarding the importance of blackleg vaccination as a preventive measure, and proper immunization protocols are available. However, few studies have evaluated the effectiveness of vaccine protection against Clostridium chauvoei and the treatment of the disease in calves exhibiting early or advanced clinical courses. This study describes twelve blackleg cases in unvaccinated calves and in calves that received a single dose of the vaccine. It also reports the recovery of some calves after antibiotic therapy. Two necropsies of cattle dead from blackleg were performed. Fragments of skeletal muscle from these two cattle were immersed in paraffin for multiplex polymerase chain reaction (PCR) analysis. Twelve calves up to nine months of age developed signs of blackleg and eight died. Ten of those 9-month-old calves had received only the first dose of a blackleg vaccine at 4 months of age, but no booster. The last two affected calves belonged to a herd that had never been vaccinated. Four out of five calves treated with penicillin for 6-7 days recovered from the disease. The diagnosis of blackleg was based on necropsy, histopathological findings and detection of C. chauvoei in skeletal muscle samples of two necropsied calves using PCR. The occurrence of cases only in calves that did not receive a booster dose or were not vaccinated indicated that the vaccine used was effective when performed as recommended by the manufacturer. However, neglecting the booster resulted in casualties due to blackleg.

Epidemiology of Bronchiolitis: Multicentric Study Policlinico-Garibaldi-Bronte-Caltagirone-Siracusa

Bronchiolitis is the most common infection of the lower airways of the 1st year. Infants with severe respiratory distress (2-3%) require hospital care. The aim of the study is to evaluate the frequency of Respiratory Virus (VRS) infection, the usefulness of the diagnostic score, the ventilatory support and the protective effect of vaccinations. 173 patients <2years admitted to 5 hospitals divided into two groups on the basis of gestational age (EG) and weight (P) were enrolled: the first (1G) of 106 (EG 38.9≤1 w, P 3253≤385,7 g) and the second (2G) of 67 (EG 35.6≤2.44 w, P 2549.8≤467.7 g). A severity score (SG) was used based on the presence of risk factors, of SaO2 <92%, respiratory distress. Age of onset, respiratory support, vaccinations, and prophylaxis with Palivizumab was evaluated.

Mechanistic Modeling of Mycobacterium tuberculosis Infection in Murine Models for Drug and Vaccine Efficacy Studies.

Tuberculosis (TB) drug, regimen, and vaccine development rely heavily on preclinical animal experiments, and quantification of bacterial and immune response dynamics is essential for understanding drug and vaccine efficacy. A mechanism-based model was built to describe Mycobacterium tuberculosis H37Rv infection over time in BALB/c and athymic nude mice, which consisted of bacterial replication, bacterial death, and adaptive immune effects. The adaptive immune effect was best described by a sigmoidal function on both bacterial load and incubation time. Applications to demonstrate the utility of this baseline model showed (i) the important influence of the adaptive immune response on pyrazinamide (PZA) drug efficacy, (ii) a persistent adaptive immune effect in mice relapsing after chemotherapy cessation, and (iii) the protective effect of vaccines after M. tuberculosis challenge. These findings demonstrate the utility of our model for describing M. tuberculosis infection and corresponding adaptive immune dynamics for evaluating the efficacy of TB drugs, regimens, and vaccines.

Venezuelan equine encephalitis vaccine with rearranged genome resists reversion and protects non-human primates from viremia after aerosol challenge

Live-attenuated V4020 vaccine for Venezuelan equine encephalitis virus (VEEV) containing attenuating rearrangement of the virus structural genes was evaluated in a non-human primate model for immunogenicity and protective efficacy against aerosol challenge with wild-type VEEV. The genomic RNA of V4020 vaccine virus was encoded in the pMG4020 plasmid under control of the CMV promoter and contained the capsid gene downstream from the glycoprotein genes. It also included attenuating mutations from the VEE TC83 vaccine, with E2-120Arg substitution genetically engineered to prevent reversion mutations. The population of V4020 vaccine virus derived from pMG4020-transfected Vero cells was characterized by next generation sequencing (NGS) and indicated no detectable genetic reversions. Cynomolgus macaques were vaccinated with V4020 vaccine virus. After one or two vaccinations including by intramuscular route, high levels of virus-neutralizing antibodies were confirmed with no viremia or apparent adverse reactions to vaccinations. The protective effect of vaccination was evaluated using an aerosol challenge with VEEV. After challenge, macaques had no detectable viremia, demonstrating a protective effect of vaccination with live V4020 VEEV vaccine.

Effect of vaccination on severity and infectiousness of measles during an outbreak in the Netherlands, 2013-2014.

An outbreak of measles in the Netherlands in 2013-2014 provided an opportunity to assess the effect of MMR vaccination on severity and infectiousness of measles.Measles is notifiable in the Netherlands. We used information on vaccination, hospitalisation, complications, and most likely source(s) of infection from cases notified during the outbreak. When a case was indicated as a likely source for at least one other notified case, we defined it as infectious. We estimated the age-adjusted effect of vaccination on severity and infectiousness with logistic regression.Of 2676 notified cases, 2539 (94.9%) were unvaccinated, 121 (4.5%) were once-vaccinated and 16 (0.6%) were at least twice-vaccinated; 328 (12.3%) cases were reported to have complications and 172 (6.4%) cases were hospitalised. Measles in twice-vaccinated cases led less often to complications and/or hospitalisation than measles in unvaccinated cases (0% and 14.5%, respectively, aOR 0.1 (95% CI 0-0.89), P = 0.03). Of unvaccinated, once-vaccinated and twice-vaccinated cases, respectively, 194 (7.6%), seven (5.1%) and 0 (0%) were infectious. These differences were not statistically significant (P > 0.05).Our findings suggest a protective effect of vaccination on the occurrence of complications and/or hospitalisation as a result of measles and support the WHO recommendation of a two-dose MMR vaccination schedule.

Influence of interferon-based drugs on immunological indices in specific prevention.

Aim:The research aimed to study the effect of interferon (IFN)-based drugs on the behavior of immunological parameters in calves during the specific prevention of associative infections.Materials and Methods:The object of research was 45 black motley cows and their calves from birth to 2 months of life. Serum and colostrum samples were screened for antibodies against Rotavirus, diarrhea, and coronavirus using serological methods. The testing was performed before vaccination, 40 days before calving, 20 days before calving, and before calving. Colostrum samples were taken during the first milk yield. Serum samples from calves were drawn before colostrum feeding as well as at 7, 14, and 21 days, and 1 and 2 months of age. To measure the level of immunoglobulins A, M, and G, additional serum samples were collected from calves at 25, 35, 65, and 75 days after birth.Results:Giving pregnant cows, an IFN-based drug at a dose of 1 ml/kg 48 h before vaccination results in the development and accumulation of antibodies to Rotavirus, coronavirus, and viral diarrhea (VD) in the colostrum, with a titer of 7.6±0.3 log2, 5.8±0.34 log2, and 4.4±0.18 log2, respectively. It indicates an increase in the antigenic activity of the multivalent vaccine.Conclusion:IFN-based drugs enhance the protective effect of vaccination against associative infections in the newborn calves. They stimulate a rise in the titer of antibodies to Rotavirus, coronavirus, VD, and mucosal disease complex as well as an increase in immunoglobulins A, M, and G.

Clinical effectiveness of 13-valent and 23-valent pneumococcal vaccination in middle-aged and older adults: The EPIVAC cohort study, 2015–2016

BackgroundClinical benefits using the 23-valent pneumococcal polysaccharide vaccine (PPsV23) or the 13-valent pneumococcal conjugate vaccine (PCV13) in adults are controversial. This study investigated clinical effectiveness for both PPsV23 and PCV13 in preventing pneumonia among middle-aged and older adults. MethodsPopulation-based cohort study involving 2,025,730 persons ≥50 years in Catalonia, Spain, who were prospectively followed between 01/01/2015 and 31/12/2016. Primary outcomes were hospitalisation from pneumococcal or all-cause pneumonia and main explanatory variable was PCV13/PPsV23 vaccination status. Multivariable Cox regression models were used to estimate vaccination effectiveness adjusted for age and baseline-risk conditions. ResultsCohort members were followed for 3,897,151 person-years (17,496 PCV13 vaccinated and 1,551,502 PPsV23 vaccinated), observing 3259 pneumococcal pneumonias (63 in PCV13 vaccinated, 2243 in PPsV23 vaccinated) and 24,079 all-cause pneumonias (566 in PCV13 vaccinated, 17,508 in PPsV23 vaccinated). Global incidence rates (per 100,000 person-years) were 83.6 for pneumococcal pneumonia (360.1 in PCV13 vaccinated, 144.6 in PPsV23 vaccinated) and 617.9 for all-cause pneumonia (3235.0 in PCV13 vaccinated, 1128.5 in PPsV23 vaccinated). In the multivariable analyses, the PCV13 appeared significantly associated with an increased risk of pneumococcal pneumonia (hazard ratio [HR]: 1.52; 95% confidence interval [CI]: 1.17–1.97; p = 0.002) and all-cause pneumonia (HR: 1.76; 95% CI: 1.61–1.92; p < 0.001) whereas the PPsV23 did not alter the risk of pneumococcal pneumonia (HR: 1.08; 95% CI: 0.98–1.19; p = 0.132) and slightly increased the risk of all-cause pneumonia (HR: 1.17; 95% CI: 1.13–1.21; p < 0.001). In stratified analyses focused on specific target population subgroups (i.e., elderly people, at-risk and high-risk individuals), protective effects of vaccination did not emerge either. ConclusionData does not support clinical benefits from pneumococcal vaccination (nor PCV13 neither PPsV23) against pneumonia among Catalonian adults in the current era of universal PCV’s childhood immunisation.