Non-vaccinated Ones Research Articles

Excess mortality in individuals with and without COVID-19 vaccination in the Netherlands in 2021

Abstract Background The COVID-19 pandemic greatly affected public health, evident in higher mortality rates in 2020-2022. COVID-19 vaccinations reduced global mortality, though this may vary across subpopulations. We aimed to study the role of COVID-19 vaccination in excess mortality by examining individuals with and without COVID-19 vaccine while accounting for characteristics such as income and frailty. Methods In this observational study, electronic health record data from general practitioners participating in the Nivel Primary Care Database were linked to demographic data and COVID-19 vaccination data. Patients were categorized in age groups, based on vaccination invitation dates, with the index date set as vaccination date for vaccinated individuals and the expected vaccination date for nonvaccinated ones. Expected mortality rates were calculated using 2015-2018 data, accounting for season, sex, income, migration background, palliative care, and frailty. We compared expected mortality to observed mortality in 2021 to determine excess mortality. Results Preliminary results show that nonvaccinated individuals (n = 160.253) were younger, and less frail, but more often received palliative care than vaccinated individuals (n = 819.363). In nonvaccinated individuals, excess mortality in the three months after expected vaccination ranged from 22-61% for 36-60 year olds to 209-233% for the 81+ year olds. In vaccinated individuals, excess mortality ranged from -64- -61% in 36-60 year olds to 2-4% in 81+ year olds. When not correcting for palliative care, excess mortality estimations increased significantly in nonvaccinated individuals (e.g. for 81+ year olds: 504%-514%). Conclusions Excess mortality was hardly present in vaccinated subgroups, while it was high in all nonvaccinated subgroups. Our study shed light on characteristics of nonvaccinated individuals, who require special attention during future vaccination programs to prevent excess mortality. Key messages • Excess mortality in the three months after (expected) COVID-19 vaccination was high among nonvaccinated individuals and hardly observed amongst vaccinated individuals. • Routine care data could help identify terminally ill individuals, who are overrepresented amongst nonvaccinated individuals, and mitigate the so called healthy vaccinee bias in vaccination research.

Covid-19 vaccination acceptance among visitors of Erbil primary health care centers

Background: Vaccination is probably the most effective approach to prevent and control COVID-19. Studies assessing acceptance towards vaccination showed huge regional variations. Objective: To find out the rate of acceptance of Covid 19 vaccine and its associated factors as well as to explore out both the most frequent reasons behind acceptance or refusal of this vaccine and the most received and preferred type. Patients and Methods: In this cross-sectional study, a convenience sample of 1000 visitors to primary health care centers (PHCCs) in Erbil/Iraq, aged 18 years and older, were collected from December 2021 to December 2022. A structured questionnaire was used for data collection through a direct interview. Results: The study showed that 43.9% of the participants accepted the vaccine. The main reason behind refusal (53.8%) was not trusting its development, while the main reasons for receiving were to protect themselves (44.2%), majority of those vaccinated (76.5%) received Pfizer, which was the most preferred type (67.4%), 10.3% of them were not completing the recommended dose and the most common reasons behind this were neglect and shortage of time (31%), and afraid from side effects (31%). A significant association found between vaccination practice with gender, education, occupation, family income and socioeconomic status. Vaccinated persons were less likely to be infected with COVID19 (20.7%) than nonvaccinated ones (62.7%). Conclusion: Less than half of the participants were accepted the vaccine and the acceptance rate significantly associated with male gender, education, occupation, family income, and socioeconomic status. Keywords: COVID-19 vaccination acceptance, vaccine, primary health care centers .

Covid-19 vaccination acceptance among visitors of Erbil primary health care centers

Background: Vaccination is probably the most effective approach to prevent and control COVID-19. Studies assessing acceptance towards vaccination showed huge regional variations. Objective: To find out the rate of acceptance of Covid 19 vaccine and its associated factors as well as to explore out both the most frequent reasons behind acceptance or refusal of this vaccine and the most received and preferred type Patients and Methods: In this cross-sectional study, a convenience sample of 1000 visitors to primary health care centers (PHCCs) in Erbil/Iraq, aged 18 years and older, were collected from December 2021 to December 2022. A structured questionnaire was used for data collection through a direct interview. Results: The study showed that 43.9% of the participants accepted the vaccine. The main reason behind refusal (53.8%) was not trusting its development, while the main reasons for receiving were to protect themselves (44.2%), majority of those vaccinated (76.5%) received Pfizer, which was the most preferred type (67.4%), 10.3% of them were not completing the recommended dose and the most common reasons behind this were neglect and shortage of time (31%), and afraid from side effects (31%). A significant association found between vaccination practice with gender, education, occupation, family income and socioeconomic status. Vaccinated persons were less likely to be infected with COVID19 (20.7%) than nonvaccinated ones (62.7%). Conclusion: Less than half of the participants were accepted the vaccine and the acceptance rate significantly associated with male gender, education, occupation, family income, and socioeconomic status.

Understanding the gap between guidelines and influenza vaccination coverage in people with diabetes: a scoping review.

Diabetes affects millions of people worldwide, making them more vulnerable to infections, including seasonal influenza. It is therefore particularly important for those suffering from diabetes to be vaccinated against influenza each year. However, influenza vaccination coverage remains low in this population. This review primarily aims to identify the determinants of influenza vaccination in people with diabetes (T1D or T2D). Secondly, it aims to assess main recommendations for influenza vaccination, vaccine effectiveness, vaccination coverage, and how education and pharmacists can encourage uptake of the vaccine in the diabetic population. A scoping review was conducted in January 2022 to systematically review evidence on influenza vaccination in people with diabetes using data from PubMed, Science Direct, and EM Premium with terms such as "Diabetes mellitus," "Immunization Programs," "Vaccination," and "Influenza Vaccines." Quality assessment and data extraction were independently conducted by two authors. Disagreements between the authors were resolved through discussion and consensus, and if necessary, by consulting a third author. Of the 333 records identified, 55 studies met the eligibility criteria for inclusion in this review. Influenza vaccination was recommended for people ≥6 months. Despite effectiveness evidence showing a reduction in mortality and hospitalizations in people with diabetes vaccinated vs. non-vaccinated ones, very few studies reported a coverage rate ≥ 75%, which is WHO's target objective. Determinants such as advanced age, presence of comorbidities and healthcare givers' advice were associated with increased vaccination uptake. On the contrary, fear of adverse reactions and concerns about vaccine effectiveness were significant barriers. Finally, education and pharmacists' intervention played a key role in promoting vaccination and increasing vaccination uptake. Influenza vaccination coverage in people with diabetes remains low despite recommendations and evidence on vaccine effectiveness. Motivators and barriers as well as several socio-demographic and clinical factors have been identified to explain this trend. Efforts are now needed to increase the number of diabetics vaccinated against influenza, mainly through education and the involvement of healthcare givers.

COVID-19 Vaccine Acceptance/Hesitancy and Influence on Infection in Patients with Multiple Myeloma: A National-Wide Multicenter Survey in China

Background Patients with multiple myeloma (MM) are immunocompromised due to impaired humoral and cellular immunity in addition to immunosuppressive therapy. The situation and protective effects of severe coronavirus disease 2019 (COVID-19) vaccination in MM patients are not clarified. The study aimed to explore the reasons of COVID-19 vaccine hesitancy and its influence on severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection in MM patients during COVID-19 Omicron BA.4/5 subvariant outbreak in China. Methods An anonymous online questionnaire designed by our team was distributed to MM patients national-wide from December 26, 2022, to April 20, 2023. Then content of questionnaire included the contents of disease status, vaccination and SARS-COV-2 infection. Results A total of 508 valid questionnaires from 30 provinces were collected all over China. The vaccination rate of COVID-19 in MM patients was only 34.1% (n=173). The overall infection rate was 57.2%. Multivariate analysis showed that demographic characteristics were not factors affecting vaccination, while those accomplishing autologous stem cell transplantation (ASCT) presented a lower vaccination rate (20.2% vs. 48.4%, P<0.001). In the survey of vaccine acceptance/hesitancy, voluntary choice (49%), concerns to COVID-19 infection (35.1%), and trust of vaccine efficacy (26.5%) were the three main reasons for receiving vaccines. Physicians' suggestion (52.0%), conflicts of MM treatment (37.8%) and concerns about MM progression (31.3%) were the top three reasons for vaccine hesitancy. Adverse events (AEs) after vaccination were mainly myalgia or joint pain, fatigue and erythema or swelling at the site of injection. No MM disease-related adverse effects were reported. Among 104 vaccinated MM patients with SARS-COV-2 infection, the median time since last vaccines to infections was 304 days (range 4-593). The infection rates between the vaccinated population (n=173) versus non-vaccinated ones (n=335) were 60.1% vs. 55.8% respectively (P=0.35). In subgroup analyses, the infection rates in vaccinated patients were lower than those in unvaccinated ones including the elderly (49.3% vs. 55.2%), obese patients (BMI≥28) (50% vs. 63.3%), and R/RMM population (42.2% vs. 66.7%, P=0.005). The proportion of hospitalized patients due to SARS-COV-2 infection in vaccinated group was significantly lower than that in unvaccinated group (4.8% vs.12.3%, P=0.038). Conclusions Vaccine hesitation is common in Chinese MM patients although inactivated COVID-19 vaccine only causes mild AEs. Lower infection rate in MM patients is probably due to strict self-quarantine. COVID-19 vaccination is not translated into less SARS-COV-2 infections, but does protect the elderly, obese or R/RMM patients from severe infections. Clinicians are suggested to encourage MM patients to receive COVID-19 vaccines for the sake of reducing severe infections and related mortality. Keywords Questionnaire; Multiple Myeloma; vaccination; SARS-COV-2; outbreak infection

Gastrointestinal symptoms among COVID-19 patients presenting to a primary health care center of Nepal: A cross-sectional study.

Coronavirus disease 2019 (COVID-19) is a major public health problem causing significant morbidity and mortality worldwide. Apart from respiratory symptoms, gastrointestinal symptoms like nausea, vomiting, diarrhea, and abdominal discomfort are quite common among COVID-19 patients. The gastrointestinal tract can be a potential site for virus replication and feces a source of transmission. Thus, ignorance of enteric symptoms can hinder effective disease control. The objective of this study is to see the gastrointestinal manifestation of the disease and its effect on morbidity and mortality. This observational cross-sectional retrospective study was carried out among 165 laboratory-confirmed COVID-19 patients in primary health care of Gorkha, Nepal from March 1, 2021 to March 1, 2022. A systematic random sampling method was adopted while data were entered and analyzed by Statistical Package for Social Sciences version 21. Of 165 patients, 97 patients (58.78%) had enteric involvement. Among gastrointestinal symptoms, diarrhea in 67 patients (40.6%) and nausea and/or vomiting in 66 patients (40%) were the most common symptoms, followed by abdominal pain in 27 patients (16.4%) and anorexia in 19 patients (11.5%). Of the majority of cases with gastrointestinal involvement, 63 (63%) were below 50 years of age. Many of the patients who received vaccination had gastrointestinal symptoms (79%). Complications like acute respiratory distress syndrome, shock, and arrhythmia developed in 9.7% of patients, with the death of eight patients. COVID-19 vaccination was associated with 4.32 times higher odds of having gastrointestinal involvement in subsequent COVID-19 infection. Diarrhea followed by nausea/vomiting was among the most common gastrointestinal symptoms affecting younger age groups in our study. Enteric symptoms were more common among vaccinated people rather than among nonvaccinated ones.

Effects of the Severe Acute Respiratory Syndrome Coronavirus 2 Inactivated Vaccine on the Outcome of Frozen Embryo Transfers: A Large Scale Clinical Study.

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a life-threatening infectious disease that has become a global pandemic. This study aimed to explore the effects of SARS-CoV-2 inactivated vaccine on the outcome of frozen embryo transfer (FET). We grouped patients who underwent FET between August 2021 and March 2022 based on their vaccination status, number of doses, and the interval between the last dose and the FET, and then compared the differences in pregnancy outcomes among the groups. There were 1084 vaccinated patients and 1228 non-vaccinated ones. There were significant differences in the live birth rate between the vaccination and non-vaccination groups (16.61% vs 28.26%), among the one-dose, two-dose, and three-dose groups (22.28% vs 19.51% vs 7.27%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (38.38% vs 27.27% vs 12.03%). There were significant differences in the persistent pregnancy rate between the vaccination and non-vaccination groups (22.88% vs 14.09%), among the one-dose, two-dose, and three-dose groups (14.51% vs 23.80% vs 38.18%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (1.01% vs 8.44% vs 28.16%). There were significant differences in the neonatal weight between the vaccination and non-vaccination groups [3805.50 (3746.00-3863.50) vs 2970.00 (2500.00-3400.00)]. There were significant differences in the premature birth rate among the one-dose, two-dose, and three-dose groups (23.26% vs 34.59% vs 100.00%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (15.79% vs 21.43% vs 37.00%). Pregnancy outcomes were not affected by taking the SARS-CoV-2 inactivated vaccine before FET, the number of doses, and the interval between doses. These findings provide evidence supporting the safety of administering the SARS-CoV-2 inactivated vaccine during pregnancy, which can be used as a guide for vaccinating patients undergoing ART.

Evaluation of IL-6, IL-25 & IL-35 in the COVID 19 Patients and their Correlation to Demography Data in the Symptomatic Patients.

The severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, was first discovered in Wuhan, Hubei province, China. Cytokines play a critical role in COVID-19 infections through their inflammatory or anti-inflammatory activities. This study aimed to detect the diagnostic value of and the relationship between the interleukins under study, in addition to their relationship with demographic data in COVID-19 patients. Patients with a confirmed diagnosis of COVID-19 based on laboratory (PCR) results and the healthy control group were given their section of this investigation. The patient group had 120 COVID-19 patients, including 62 males and 58 females, while the control group consisted of 32 individuals (22 males and 10 females). The subdivision was then performed according to their vaccination status, chronic diseases, gender, and residence. Cytokine levels were detected using the ELISA technique. The immunological status of COVID-19 patients was determined by measuring interleukin (IL)-6, IL-25, and IL-35. During the research, it was found that IL-6 was highly significant in COVID-19 patients (0.001). However, its level was not significantly different (0.376) in patients regarding the type of chronic diseases, residence (0.353), and gender (0.574), but it was significantly different in vaccinated patients (0.029). It was also found that IL-6 is significantly correlated with IL-25 and IL-35. IL-25 was highly significant in COVID-19 patients (0.007), and there was a significant difference in its level in patients regarding the type of chronic disease (0.049). While there was no difference in terms of residence (0.421) and gender (0.681), corona vaccination showed a significant difference (0.047). IL-25 also had a significant correlation with IL-6 and IL-35. As for IL-35, it was significant in patients with COVID-19 (0.013) but not significantly different regarding chronic diseases (0.344), residence (0.877), or gender (0.800). However, it was significantly different in vaccinated patients, compared to the non-vaccinated ones. IL-35 was found to be significantly correlated with IL-25 and IL-6 (0.000). The examined interleukins increased in COVID-19 individuals. IL-6 remains an excellent marker for determining the immune state of patients with COVID-19. There were also strong correlations between the interleukins under study in COVID-19 patients. However, there was no relationship between age, residence, gender, and the concentration of studied cytokines. IL-25 increases significantly in COVID-19 patients suffering from chronic diseases. Therefore, it is more efficient in the follow-up of patients.

Efficacy Studies against PCV-2 of a New Trivalent Vaccine including PCV-2a and PCV-2b Genotypes and Mycoplasma hyopneumoniae When Administered at 3 Weeks of Age.

This study aimed to evaluate the efficacy of a new trivalent vaccine containing inactivated Porcine Circovirus 1-2a and 1-2b chimeras and a Mycoplasma hyopneumoniae bacterin administered to pigs around 3 weeks of age. This trivalent vaccine has already been proved as efficacious in a split-dose regimen but has not been tested in a single-dose scenario. For this purpose, a total of four studies including two pre-clinical and two clinical studies were performed. Globally, a significant reduction in PCV-2 viraemia and faecal excretion was detected in vaccinated pigs compared to non-vaccinated animals, as well as lower histopathological lymphoid lesion plus PCV-2 immunohistochemistry scorings, and incidence of PCV-2-subclinical infection. Moreover, in field trial B, a significant increase in body weight and in average daily weight gain were detected in vaccinated animals compared to the non-vaccinated ones. Circulation of PCV-2b in field trial A and PCV-2a plus PCV-2d in field trial B was confirmed by virus sequencing. Hence, the efficacy of this new trivalent vaccine against a natural PCV-2a, PCV-2b or PCV-2d challenge was demonstrated in terms of reduction of histopathological lymphoid lesions and PCV-2 detection in tissues, serum and faeces, as well as improvement of production parameters.

Carboxyl-Terminal Decoy Epitopes in the Capsid Protein of Porcine Circovirus Type 2 Are Immunogenicity-Enhancers That Elicit Predominantly Specific Antibodies in Non-Vaccinated Pigs.

In the context of the carboxyl-terminus (C-terminus) of the capsid protein of porcine circovirus type 2a (PCV2a) and PCV2a vaccines, this study aimed to explore its unrevealing cryptic epitope and its relation to PCV2-infected herd immunity. To discover the C-terminus of the capsid protein of PCV2a, monoclonal antibodies (mAbs) were generated in this work. Two mAbs bound the two minimal linear epitopes (229PPLKP233 and 228DPPLNP233 (or 229PPLNP233)), which were located at the C-terminus of the capsid proteins of PCV2a and PCV2b, respectively. One mAb bound to the minimal linear epitope (220QFREFNLK227, peptide P82), but it neither bound the virus-like particle (VLP) of PCV2a nor produced positive staining in PCV2a-infected cells by immunofluorescence assay. Further, the residues 220-227 were not accessible on the surface of the VLP on the three-dimensional model, but the residues 228-231 extend toward the VLP exterior. Immunoassays were conducted in this study to screen anti-viral peptide-specific IgGs, which could differentiate vaccinated pigs from non-vaccinated ones. The data show two 220QFREFNLKDPPLKP233-containing peptides had a significantly higher binding reactivity with sera from PCV2-infected pigs in the control group than with sera from the VLP-vaccine group, particularly seen in sera from swine aged 15 weeks to 24 weeks. However, the peptide P82 had not this phenomenon in that test. This study confirmed that C-terminal epitopes play an important role in PCV2-induced decoy of swine humoral immunity.

Efficacy Studies of a Trivalent Vaccine Containing PCV-2a, PCV-2b Genotypes and Mycoplasma hyopneumoniae When Administered at 3 Days of Age and 3 Weeks Later against Porcine Circovirus 2 (PCV-2) Infection.

Four studies under preclinical and clinical conditions were performed to evaluate the efficacy of a new trivalent vaccine against Porcine circovirus 2 (PCV-2) infection. The product contained inactivated PCV-1/PCV-2a (cPCV-2a) and PCV-1/PCV-2b (cPCV-2b) chimeras, plus M. hyopneumoniae inactivated cell-free antigens, which was administered to piglets in a two-dose regime at 3 days of age and 3 weeks later. The overall results of preclinical and clinical studies show a significant reduction in PCV-2 viraemia and faecal excretion, and lower histopathological lymphoid lesions and PCV-2 immunohistochemistry scores in vaccinated pigs when compared to non-vaccinated ones. Furthermore, in field trial A, a statistically significant reduction in the incidence of PCV-2-subclinical infection, an increase in body weight from 16 weeks of age to slaughterhouse and an average daily weight gain over the whole period (from 3 days of age to slaughterhouse) was detected in the vaccinated group when compared to the non-vaccinated one. Circulation of PCV-2a in field trial A, and PCV-2b plus PCV-2d in field trial B was confirmed by virus sequencing. In conclusion, a double immunization with a cPCV-2a/cPCV-2b/M. hyopneumoniae vaccine was efficacious against PCV-2 infection by reducing the number of histopathological lymphoid lesions and PCV-2 detection in tissues, serum, and faeces, as well as reducing losses in productive parameters.

Comparison of the COVID-19 Pandemic Waves in 2020 and 2021

The daily number of new COVID-19 cases and deaths per capita are important characteristics of the pandemic dynamics indicating the appearance of new coronavirus strains, the effectiveness of quarantine, testing and vaccination. The second year of the pandemic allowed us to compare the averaged daily number of cases and deaths in the period from September to December 2020 with the same period in 2021 in some northern countries and regions: Ukraine, EU, the UK, USA, some countries located in tropical zone and south hemisphere: India, Brazil, South Africa and Argentina and in the whole world in order to find some correlations with seasonal factors, the percentage of the fully vaccinated people and boosters. The results showed that existing vaccines cannot prevent new infections and vaccinated people can spread the infection as intensively as non-vaccinated ones, but vaccinations can diminish the numbers of death per capita

COVID-19 Vaccination Limits Systemic Danger Signals in SARS-CoV-2 Infected Patients.

Vaccination with an mRNA COVID-19 vaccine determines not only a consistent reduction in the risk of SARS-CoV-2 infection but also contributes to disease attenuation in infected people. Of note, hyperinflammation and damage-associated molecular patterns (DAMPs) have been clearly associated with severe illness and poor prognosis in COVID-19 patients. In this report, we revealed a significant reduction in the levels of IL-1ß and DAMPs molecules, as S100A8 and High Mobility Group Protein B1 (HMGB1), in vaccinated patients as compared to non-vaccinated ones. COVID-19 vaccination indeed prevents severe clinical manifestations in patients and limits the release of systemic danger signals in SARS-CoV-2 infected people.

A Novel Potential Therapeutic Tool to Increase Efficiency of Available COV-19 Vaccines

A side from the activation of the immune cells and the noticed increase of cytokine levels in COVID-19 patients who have cytokine storm, it has been proved that they have multiple clinical and laboratory irregularities as renal dysfunction and CRP, in addition hyper-inflammation and tissue damage that found to predict worse effects of COVID-19. Over production of cytokines during SARS-CoV-2 can result in damage of lung tissues, ARDS and death. Many studies recently reported that severity of the disease was significantly lower in the vaccinated individuals who get infected with COVID-19 compared to nonvaccinated ones. There are contradictory data with regard to the immunological effect of COVID-19 vaccines. No evidence of raised cytokines levels was shown in vaccinated people with Moderna and Pfizer-BioNTech. On the other hand, Covaxin increases plasma levels of some cytokines like IFNγ, IL-2, TNFα, IL-4, IL-5, IL-10, IL-13 and others but reduced levels of other cytokines as IL-25, IL-33 and GM-CSF. Pfizer reduced the production of the pro-inflammatory cytokines, TNF-α and IL-1β. The current review highlights updates on the immunological aspects of COVID-19 and its vaccines. After elaborating advanced research studies, cytokine inhibitors and JAK inhibitors could be used in adjunct with available vaccines or as promising therapeutic target for severe cases of COVID-19.

Scaling the changes in lifestyle, attitude, and behavioral patterns among COVID-19 vaccinated people: insights from Bangladesh

ABSTRACT With the advent of COVID-19 vaccines, countries around the globe are anticipating a way out from the pandemic. Despite being an initiative to contain the COVID-19 virus spreading, the mass vaccination program also raised concerns about its consequences on the lifestyle, attitude, and behavioral pattern of vaccinated people in the post-vaccination period. With this in mind, this study investigated changes in lifestyle, attitude, and behavior among vaccinated people in Bangladesh. A cross-sectional survey was conducted incorporating 1227 COVID-19 vaccinated respondents from eight divisions of Bangladesh. The relative importance index (RII) was used to assess the most compelling lifestyle, attitude, and behavior changes, while binary logistic regression was used to identify factors driving the changes. Findings disclosed that respondents increased the physical contact with non-vaccinated ones and amplified consuming nutritious food after vaccination. The inclination of avoiding distance, handshaking, abandoning sanitizer and mask, visiting crowded places, traveling, and staying outside longer was found to be increased among vaccinated individuals. Surprisingly, about seven out of ten surveyed respondents exhibited a sedentary lifestyle, while 67.37% of respondents showed negative behavioral changes following the vaccination period. A positive attitude was observed in encouraging others to be vaccinated against COVID-19. However, 92% of the respondents positively changed their attitude toward the COVID-19 vaccine after vaccination. Furthermore, the participants’ age, residence, economic status, and educational level influenced lifestyle, attitude, and behavioral changes positively. The study recommends informing citizens about the opacity of vaccinations’ ability to contain infections and encouraging them to continue following COVID-19 protective guidelines.

Salmonella Typhimurium lacking phoBR as a live vaccine candidate against poultry infection

Salmonella enterica serovar Typhimurium, with a broad-host range, is a predominant cause of non-typhoidal Salmonella infection in humans, and the infectious source is highly associated with food animals, especially poultry. Considering the horizontal transmission of S. Typhimurium from farm animals to humans, vaccination has been strongly recommended in industrial animals. In an effort to eradicate S. Typhimurium in poultry farms, a live candidate vaccine strain lacking the phoBR genes, which encode the PhoB/PhoR two-component regulatory system responsible for cellular phosphate signaling, was evaluated in mice and chickens. Lack of the phoBR genes promoted overgrowth of intracellular Salmonella. However, notably, in BALB/c mouse models, the ΔphoBR mutant showed attenuated virulence and instead, provided protection against infection with virulent Salmonella, thereby clearing out Salmonella in the spleen and liver. Accordingly, immunization with the ΔphoBR mutant increased immunoglobulin (Ig)G and IgM antibody responses and also tended to increase the IgG2a/IgG1 ratio, which is indicative of T helper (Th)1-mediated cellular immunity. In chicken challenge models, immunization with the ΔphoBR mutant significantly boosted the production of IgG and IgM antibodies after the second vaccination. The vaccinated chickens ceased fecal shedding of challenged Salmonella earlier than the non-vaccinated ones and showed no Salmonella in their caecum and ileum. These results demonstrate the potential of the S. Typhimurium ΔphoBR mutant as a vaccine in chickens.

New COVID-19 Pandemic Waves Caused by Omicron and Efficiency of Vaccinations

The sharp increase in the number of new COVID-19 cases in late 2021 and early 2022, which is associated with the spread of a new strain of coronavirus - omicron - is of great concern and makes it necessary to make at least approximate forecasts for the pandemic dynamics of the epidemic. As this rapid growth occurs even in countries with high levels of vaccinations, the question arises as to their effectiveness. The smoothed daily number of new cases and deaths per capita and the ratio of these characteristics were used to reveal the appearance of new coronavirus strains and to estimate the effectiveness of quarantine, testing and vaccination. The third year of the pandemic allowed us to compare the pandemic dynamics in the period from September 2020 to January 2021 with the same period one year later for Ukraine, EU, the UK, USA, India, Brazil, South Africa, Argentina, Australia, and in the whole world. Record numbers of new cases registered in late 2021 and early 2022 once again proved that existing vaccines cannot prevent new infections, and vaccinated people can spread the infection as intensively as non-vaccinated ones. Fortunately, the daily number of new cases already diminishes in EU, the UK, USA, South Africa, and Australia. In late January - early February 2022, the maximum averaged numbers of new cases are expected in Brazil, India, EU, and worldwide. Omicron waves can increase the numbers of deaths per capita, but in highly vaccinated countries, the deaths per case ratio significantly decreases. Highlights: Vaccinated persons can get and pass the new coronavirus variants. The probability of death is much lower for vaccinated persons.

Exploratory field study on the effects of porcine circovirus 2 (PCV-2) sow vaccination at different physiological stages mimicking blanket vaccination

BackgroundThe objective of the present study was to explore the benefits of Porcine circovirus 2 (PCV-2) blanket vaccination in a sow herd on productive parameters, PCV-2 infection and immune status in sows and their progeny. For this purpose, 288 sows were distributed among four balanced experimental groups. One group remained as negative control group and the other three received 1 mL of PCV-2 Ingelvac Circoflex® intramuscularly at different productive cycle moments: before mating, mid gestation (42–49 days post-insemination) or late gestation (86–93 days post-insemination); phosphate buffered saline (PBS) was used as negative control item. Reproductive parameters from sows during gestation and body weight of their progeny from birth to weaning were recorded. Additionally, blood was collected from sows at each vaccination time and piglets at 3 weeks of age. Moreover, up to 4 placental umbilical cords (PUC) per sow were taken at peri-partum. Sera from sows and piglets were analysed for PCV-2 antibody detection using an enzyme-linked immunosorbent assay (ELISA). Sera from sows and PUC were tested to quantify viraemia using a real time quantitative polymerase chain reaction (qPCR) assay.ResultsGlobally, results indicated that vaccinated sows showed heavier piglets at birth and at weaning, less cross-fostered piglets, lower viral load at farrowing as well as in PUC, and higher antibody levels at farrowing, compared to non-vaccinated ones. When all groups were compared among them, sows vaccinated at mid or late gestation had heavier piglets at birth than non-vaccinated sows, and lower proportion of PCV-2 positive PUC. Also, cross-fostering was less frequently practiced in sows vaccinated at pre-mating or mid gestation compared to non-vaccinated ones.ConclusionsIn conclusion, the present study points out that PCV-2 sow vaccination at different time points of their physiological status (mimicking blanket vaccination) offers benefits at production and serological and virological levels.

Adaptive Immune Response to <i>Mycobacterium abscessus</i> Complex and Cross-Reactivity of BCG Vaccination

Background: Mycobacterium abscessus complex (MABSC) is a major pathogenic group among nontuberculous mycobacteria (NTM). Here we characterized the adaptive immune response to MABSC and its cross reactivity with Mycobacterium bovis (Bacille Calmette-Guerin, BCG) using cystic fibrosis (CF) lung infection as a model. Methods: This was a cross-sectional study enrolling CF patients with and without history of NTM infection (CF/NTM+ and CF/NTM-), non-CF controls vaccinated and not vaccinated with BCG (C/BCG+ and C/BCG-). The anti-MABSC response was assessed in terms of lymphocyte activity and cytokine production after challenge with MABSC, and measurement of specific IgG. Results: The CF/NTM+ and C/BCG+ groups had cellular and cytokine responses with similar intensity, characterized by a Th1-dominated phenotype – high CD4 T-cell proliferation, increased IFN-γ and TNF-α production. The B-cell response and its associated cytokines CD40L and IL-4 were less pronounced, although IgG levels were higher in the CF/NTM+ group than in controls. Proliferating lymphocytes, increased IFN-γ and TNF-α production were also observed in part of the individuals of the CF/NTM- and C/BCG- groups, indicating environmental exposure, undetected or past infection. IL-2 increased only in the CF groups and may be specifically linked to the anti-MABSC response. Altogether, BCG-vaccinated individuals (CF and non-CF) had higher lymphocyte proliferation intensity than the non-vaccinated ones. Conclusion: The anti-MABSC response follows a pattern seen in other mycobacterial infections. BCG vaccination provides a cross-reactive response against MABSC and can have potential to mitigate the pathology of NTM infections. The potential of cytokine measurement for diagnosing MABSC infection is under investigation. Funding Information: RMM was granted a fellowship by the Sao Paulo Research Foundation (FAPESP, grant reference #2019/14134-5) and the study received funds from the Cystisk Fibrose Foreningen (Danish Cystic Fibrosis Association). Declaration of Interests: The authors have no conflicts of interests to declare. Ethics Approval Statement: The study was approved by the Regional Scientific Ethical Committees, Denmark (VEK, RH-19022288) and was in accordance with the Declaration of Helsinki and guidelines from the Danish Data Protection Agency. All participants signed a written informed consent, confirming their voluntary participations.

Admission to Educational Organizations in Case of Refusal to Vaccinate

The aspects of the refusal to perform preventive vaccination and its outcomes in the frame of admission to educational organizations, as well as aspects of separation of vaccinated children from non-vaccinated ones are considered in this article according to the current legal regulation for this topic and to the litigation practice materials. Recommendations on Russian legislation improvement in the area of interest have been developed. The possibility of children (without performed tuberculin sensitivity test) admission to educational organizations is analyzed. The admissibility of the requirements for medical data provision on the child's health state at his admission to school is being considered. The current change initiatives on the legislation in the field of preventive immunization are discussed.