Tetanus vaccination, antibody persistence and decennial booster: a serosurvey of university students and at-risk workers

A Rare Case of Tetanus With Early Manifestation of Apnea But Without Trismus

BACKGROUND

Tetanus is a life-threatening disease caused by tetanus neurotoxin (TeNT) produced by Clostridium tetani. Early symptoms of tetanus are trismus and muscle stiffness, both caused by spasticity. TeNT mainly exerts its effect by impairment of inhibitory neurons in the spine and brainstem, resulting in the hyperactivity of motor neurons, which causes spasticity and muscle spasms. Apnea is not a symptom that is predicted to occur in the early stages.

CASE REPORT

We present a rare case of severe tetanus with an early manifestation of apnea but without trismus. We believe that apnea was caused by spasms of the intercostal muscles and its early manifestation was due to a high load of TeNT, considering that the speed of disease progression is related to disease severity. We hypothesize that the absence of trismus was also due to a high load of TeNT, exerting toxic effect at the neuromuscular junction and causing flaccid paralysis of the masseters. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Since there is no diagnostic laboratory test for tetanus, emergency physicians must be well aware of symptoms that may or may not appear in tetanus. Tetanus should be considered as a differential diagnosis for patients arriving at the emergency department with apnea as an early symptom. The absence of trismus should not rule out the possibility of tetanus.

Revitalizing tetanus vaccine literacy post road accidents: a comprehensive examination of knowledge and awareness initiative among non-medical university students in Lahore, Pakistan

Introduction

Tetanus, caused by Clostridium tetani, poses a life-threatening risk by affecting the nervous system and inducing muscle tightness. The objective of this study is to examine the knowledge, attitudes, and behaviors of non-medical university students regarding the tetanus vaccine in the context of post-road accidents.

Methods

A descriptive cross-sectional study was conducted in 2023, involving 378 students from non-medical disciplines, primarily from information technology, business administration, and engineering faculties, with a mean age of 20.7 years. The sample size was calculated using the Raosoft sample calculator, and participants were selected via consecutive random sampling. Data was collected through a structured, self-administered questionnaire and analyzed using SPSS 22.0.

Results

Gender distribution was 51.6% female and 48.4% male. Out of the 378 students, 53.4% (p=0.003) were unaware of tetanus contraction sources, 52.8% (p=0.004) lacked knowledge of its symptoms and 68.3% (p=0.004) were unfamiliar with the total number of doses. An appreciable 88.9% (p0.063) are willing to receive post-accident tetanus vaccination, reflecting positive attitudes and openness to preventive measures. Similarly, the p-values >0.05 show no gender disparity in willingness to receive tetanus vaccination (p=0.063) and recommending vaccination to others after a road accident (p=0.879).

Conclusions

Notwithstanding participants' positive attitudes, the results indicate poor knowledge of tetanus regarding its transmission, symptoms, and doses. Interventions should focus on refining practical aspects of education, including symptom recognition, vaccine efficacy, duration, and the importance of sustaining immunity.

Loss of humeral immunity in childhood cancer survivors not having undergone hematopoietic stem cell transplantation

BACKGROUND

Data are limited and conflicting regarding loss of immunity in childhood cancer survivors who did not undergo hematopoietic stem cell transplantation. The purpose of this retrospective, single center study is to provide further data to help build unifying revaccination guidelines post-chemotherapy in childhood cancer survivors not having undergone hematopoietic stem cell transplantation.

METHODS

This retrospective study included 28 childhood cancer survivors, 14 males and 14 females, whose treatment consisted of at least 3 months of chemotherapy and with confirmation of completing their primary vaccination series prior to therapy. The rate of vaccine titer seropositivity for cancer survivors was compared with the expected general population, based on long-term studies of anti-body persistence.

RESULTS

Decreased seropositivity for measles, mumps, rubella, varicella, tetanus, and hepatitis B was found in patients across all categories of malignancy compared with the general population. However, tetanus was not statistically significant. Results were more pronounced for those with hematological malignancies.

CONCLUSIONS

This study indicates that pediatric cancer survivors, especially those with hematological malignancies, may have greater loss of protective antibodies from primary vaccinations. Further studies are needed to provide guidelines for revaccination of both hematologic malignancies and solid tumor childhood cancer survivors who did not undergo hematopoietic stem cell transplantation.

HIV infection and the implication for COVID-19 vaccination

Abstract

Human immunodeficiency virus (HIV) is associated with altered cellular and humoral immune response, especially in patients with an untreated or chronic infection. This may be due to direct and/or indirect HIV viral activities resulting in T- and B-cells dysfunctions. Although still unclear, various studies have proposed that HIV infection may exacerbate the clinical outcomes of COVID-19. Indeed, COVID-19 vaccines were developed in record time and have been shown to reduce the severity of COVID-19 in the general population. These vaccines were also earmarked as a solution to global disruptions caused by the COVID-19 pandemic. HIV infection has been reported to reduce the efficacy of various other vaccines including those used against Streptococcus pneumoniae, Clostridium tetani, and influenza viruses. However, current guidelines for the administration of available COVID-19 vaccines do not account for the immune-compromised state of people living with HIV (PLWH). We discuss here the potentials, nature, and implications of this HIV-induced dampening of the humoral immune response on COVID-19 vaccines by first reviewing the literature about efficacy of previous vaccines in PLWH, and then assessing the proportion of PLWH included in phase III clinical trials of the COVID-19 vaccines currently available. The clinical and public health implications as well as suggestions for governments and non-governmental organizations are also proposed in the context of whether findings on the safety and efficacy of the vaccines could be extended to PLWH.

Impacts

The human immunodeficiency virus (HIV) is characterized by attenuated humoral immunity that may reduce the efficacy of vaccines in people living with HIV (PLWH). Vaccination against the SARS-CoV-2 infection remains the main public health answer to the COVID-19 pandemic.Although no significant safety concerns have been raised regarding the COVID-19 vaccines in PLWH, the efficacy of these vaccines in PLWH has not received due attention. Indeed, phase III clinical trials for the safety and efficacy of COVID-19 vaccines involved a significantly low number of PLWH.There are major gaps in knowledge on the efficacy of COVID-19 vaccines in PLWH and until further research is carried out, PLWH should be prioritized along with other at-risk groups for repeated vaccination and safeguard.

Advances in Irradiated Livestock Vaccine Research and Production Addressing the Unmet Needs for Farmers and Veterinary Services in FAO/IAEA Member States

The Animal Production and Health section (APH) of the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture at the International Atomic Energy Agency has over the last 58 years provided technical and scientific support to more than 100 countries through co-ordinated research activities and technical co-operation projects in peaceful uses of nuclear technologies. A key component of this support has been the development of irradiated vaccines targeting diseases that are endemic to participating countries. APH laboratories has over the last decade developed new techniques and has put in place a framework that allows researchers from participating member states to develop relevant vaccines targeting local diseases while using irradiation as a tool for improving livestock resources.

Durability of tetanus seroprotection in people living with HIV

OBJECTIVES

Estimate the durability of tetanus toxoid (TT) -specific seroprotection in a cohort of people living with HIV (PLWH).

DESIGN

Cross-sectional study.

METHODS

PLWH with a last date of TT booster available were identified. TT-specific IgG were detected using commercial ELISA kit. Durability of seroprotection was estimated using linear regression model and analyzed according to the country of birth. The impact of baseline parameters at the time of vaccination (CD4+ T cell count, viral load and ART) was also assessed.

RESULTS

One-hundred and three subjects were included. The median duration between last TT booster and sampling was 5.6 years (IQR 2.6-8.9). Using linear regression model, half-life of TT-specific antibody was estimated at 9.9 years (95% CI: 5.5-50) in the whole cohort. Half-life was reduced in subjects born outside Europe: 4.4 years (95% CI: 2.9-8.5). PLWH born outside Europe had lower CD4+ T cell count at the time of immunization and more frequently a CD4+ T cell count nadir<200 mm3 before vaccination.

CONCLUSIONS

PLWH born outside Europe have lower half-life of TT-specific antibody as compared to previous study performed in the general population. Possible causes include lower nadir or current CD4+ T cell count or under-immunization status in country of origin before migration. Longer interval of booster vaccination, as recommended in the general population, might not be appropriate in this subgroup of PLWH.

Investigation of the baseline tetanus antibody level and its persistence in a military unit

OBJECTIVES

To determine tetanus antibody levels in army recruits and evaluate the persistence of immunity following tetanus booster immunization in adults.

METHODS

A total of 680 recruits were selected for observation of their tetanus antibody levels. From 2005 to 2015, 691 peacekeepers with tetanus vaccination were included in the questionnaire-based and serological survey based on cluster stratification. The tetanus antibody-positive rate, geometric mean concentration (GMC), and their respective changes over time were analyzed in different age groups, regions, and years after tetanus booster immunization.

RESULTS

The positivity rates of tetanus antibodies in the recruits and peacekeepers were 74.85% and 99.86%, respectively (χ² = 193.00, P < 0.05) and the antibody GMCs were 0.05 and 0.70 IU/mL (t = 15.73, P < 0.05). The antibody positivity rates of recruits from 12 provinces ranged from 47.62% (Hubei) to 100% (Inner Mongolia) (χ² = 37.24, P < 0.05) and the antibody GMCs ranged from 0.02 (Hubei) to 0.09 IU/mL (Heilongjiang) (F = 5.19, P < 0.01). Among the 691 peacekeepers, no statistically significant difference in antibody positivity rate was detected between men and women. After administration of one booster dose of the tetanus vaccine, a protective antibody level was calculated to persist up to 22 years; a significant difference in antibody levels was observed within 10 years between one and two or more booster doses.

CONCLUSION

The rate at which recruits tested positive for tetanus antibodies was low. Thus, it is necessary to screen for tetanus antibodies during military recruitment and implement a precision-based booster immunization protocol for tetanus vaccine. Moreover, one dose of the tetanus vaccine booster has been calculated to maintain a protective antibody level up to 22 years, without the need for repeated reinforcements during this period.

Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to cobalt-60 gamma radiation

BACKGROUND

Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects. Therefore, the aim of this study was to characterize the tetanus toxin structure after different doses of ionizing radiation of 60Co.

METHODS

Irradiated and native tetanus toxin was characterized by SDS PAGE in reducing and non-reducing conditions and MALD-TOF. Enzymatic activity was measured by FRET substrate. Also, antigenic properties were assessed by ELISA and Western Blot data.

RESULTS

Characterization analysis revealed gradual modification on the tetanus toxin structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the identification up to the dose of 4 kGy. At subsequent doses, peptide identification was minimal. The analysis of the enzymatic activity by fluorescence showed 35 % attenuation in the activity even at higher doses. In the antigenic evaluation, anti-tetanus toxin antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels.

CONCLUSION

Ionizing radiation promoted structural changes in the tetanus toxin such as fragmentation and/or aggregation and attenuation of enzymatic activity as the dose increased, but antigenic recognition of the toxin remained at good levels indicating its possible use as an immunogen. However, studies of enzymatic activity of tetanus toxin irradiated with doses above 8 kGy should be further analyzed.

Inactivated tetanus as an immunological smokescreen: A major step towards harnessing tetanus-based therapeutics

BACKGROUND AND PURPOSE

Tetanus neurotoxin has many potential therapeutic applications, due to its ability to increase localised muscle tone when injected directly into a muscle. It is a closely related molecule to botulinum neurotoxin (most commonly known as Botox), which has been widely used to release muscle tension for therapeutic and cosmetic applications. However, tetanus toxin has been relegated to the "maybe pile" for protein therapeutics - as most of the population is vaccinated, leading to highly effective antibody-mediated protection against the toxin. The potential for tetanus-based therapeutics remains substantial if the problem of pre-existing immunity can be resolved.

EXPERIMENTAL APPROACH

A well-established murine model of localised muscular contraction was utilised. We administered functional tetanus toxin combined with an immunogenic, but functionally inactive, decoy molecule.

KEY RESULTS

Incorporation of the decoy molecule greatly reduces the dose of active toxin required to induce a localised increase in muscle tone in mice vaccinated with the human toxoid vaccine.

CONCLUSION AND IMPLICATIONS

Our results clearly demonstrate that the barriers to developing a tetanus toxin therapeutic are not insurmountable and the technology presented here is the first major step towards realising the therapeutic potential of this powerful neurotoxin. Opening the therapeutic potential of tetanus toxin will have huge implications for the wide range of diseases caused by low-tone muscle.

An Unusual Case of Evolving Localized Tetanus Despite Prior Immunization and Protective Antibody Titer

Centers for Disease Control and Prevention has reported that tetanus infection in a fully immunized person with the last dose within 10 years is extremely rare. The prevalence of localized tetanus in such a scenario is unknown. Only two case reports of localized tetanus in previously immunized patients have been reported so far, making this the third one. Also, this is the first case of its kind to demonstrate evolving localized tetanus. Our patient is a 19-year-old man who presented with shortness of breath, pain in right upper extremity, shoulder, and neck. His chest X-ray and creatine kinase were normal. The patient was sent home. He presented again to our hospital two days later with difficulty swallowing and speaking as well as chest tightness. Routine blood tests, electrocardiogram, CT angiography of the chest, and transthoracic echocardiogram were normal. He gave a history of a cut in the right middle finger while removing the carpet a week before his presentation. His immunization history was complete with documented last tetanus shot nine years and two months ago. He was treated with tetanus vaccine and penicillin. His tetanus antitoxoid titer came out protective.

Tetanus vaccination status in construction workers: results from an institutional surveillance campaign

Background:

Since 1963 Italian law (Law 292/1963, Legislative Decree n.81/2008), defines Tetanus Vaccination (TeV) as mandatory for defined occupational categories, including Construction Workers (CWs).

Materials and Methods:

An institutional survey on of CWs was performed in the Autonomous Province of Trento (Oct. 2016 - Apr. 2017). Vaccination booklets/certificate were retrieved recalling: TeV status (1), and TeV settings (2), i.e. basal schedule; year of last shot, healthcare providers who performed TeV, and TeV formulate(s).

Results:

Data about 205 CWs were collected (mean age 40.6±10.3 years; 78.0% <50 year-old, 71.7% born in Italy). Overall, 38.5% of CW had received last vaccination shot >10 years before the survey (mean: 8.8 ± 8.2 years). The majority of boosters had been administered by Vaccination Services of the Local Health Unit (47.3%), followed by Occupational Physicians (20.0%) and General Practitioners (11.2%). In 85.9% of CWs, a monovalent formulation was used. Combined TeV were mainly reported in CW who had received last vaccination shot in Vaccination Services (96.2%; p<0.001).

Conclusions:

TeV coverage rates in CWs are insufficient, and vaccination shots are frequently performed with inappropriate, monovalent formulates. As only professionals from Vaccination Services systematically employ combined vaccines and particularly Tdap, our results not only stress the opportunity for promoting TeV among CWs, but also the importance of improving reception of up to date official recommendations in Occupational Physicians, General Practitioner and professionals of Emergency Departments. (www.actabiomedica.it)

Predictors of the immune response to booster immunisation against tetanus in Czech healthy adults

An evaluation of the relationship between predictors and immune response was conducted using data obtained from a clinical trial in 200 Czech healthy adults aged 24-65 years receiving a booster dose of a monovalent tetanus vaccine in 2017. The response was determined from ELISA antibody concentrations of paired sera obtained before and 4 weeks after the immunisation. While all subjects with initial antibody levels 2.2 IU/ml. The immune response was not affected by sex, age, tetanus vaccine type, concomitant medication, related adverse events or post-vaccination period since there were no significant differences in geometric mean concentrations or seroconversion rates. The seroconversion rate of 56% in smokers was significantly lower than that of 73% achieved in non-smokers. Although the seroconversion rates did not differ between individuals with normal or higher body weight, the adjusted odds ratio (1.3; 95% Cl 1.08-1.60) revealed a positive correlation between seroconversion rate and body mass index (BMI). Although the vaccine-induced response was influenced by pre-vaccination antibody levels, smoking or BMI, the booster immunisation against tetanus produced a sufficient response regardless the predictors.

Tetanus - A Rare But Real Threat

Tetanus is a potentially fatal disease of the nervous system arising from toxins produced by Clostridium tetani, an anaerobic bacterium found in soil [1]. Characterized by muscular rigidity, spasms and autonomic dysregulation its identification and, importantly, its prevention remain critical to the welfare of at risk patients. We present the case of a twenty two year old woman who presented to hospital with trismus and generalized muscle spasms three days following a dog bite to the right hand. Here, we discuss the presentation of generalized tetanus and the use of neurophysiology to facilitate its diagnosis.