Regulation of Clostridium tetani Neurotoxin Expression by Culture Conditions

Background: Ensuring consistency of tetanus neurotoxin (TeNT) production by Clostridium tetani could help to ensure consistent product quality in tetanus vaccine manufacturing, ultimately contributing to reduced animal testing. The aim of this study was to identify RNA signatures related to consistent TeNT production using standard and non-standard culture conditions. Methods: We applied RNA sequencing (RNA-Seq) to study C. tetani gene expression in small-scale batches under several culture conditions. Results: We identified 1381 time-dependent differentially expressed genes (DEGs) reflecting, among others, changes in growth rate and metabolism. Comparing non-standard versus standard culture conditions identified 82 condition-dependent DEGs, most of which were specific for one condition. The tetanus neurotoxin gene (tetX) was highly expressed but showed expression changes over time and between culture conditions. The tetX gene showed significant down-regulation at higher pH levels (pH 7.8), which was confirmed by the quantification data obtained with the recently validated targeted LC-MS/MS approach. Conclusions: Non-standard culture conditions lead to different gene expression responses. The tetX gene appears to be the best transcriptional biomarker for monitoring TeNT production as part of batch-to-batch consistency testing during tetanus vaccine manufacturing.

Clostridium Tetani and Tetanus

Tetanus is acquired through exposure to the environmental spore-forming Gram-positive bacillus Clostridium tetani, which may infect human wounds and cause disease by production of an exotoxin (tetanospasmin). There is no human-to-human transmission. The disease occurs worldwide and it is sporadic in high-income countries with universal access to well-accepted immunization programs. It is more common in agricultural regions and in low-income countries where contact with animal excreta is more likely and immunization programs are inadequate. Neonatal tetanus (NNT) following unclean deliveries and poor postnatal hygiene is still responsible for the majority of tetanus cases and deaths; the majority of NNT occurs in poor Asian and African countries, whereas in high-income countries the disease is extremely rare. Three forms of clinical disease can be distinguished: the most common form is generalized tetanus, whereas local tetanus and cephalic tetanus are rare. Neonatal tetanus (NNT) is a form of generalized tetanus in newborns. The case fatality rate of tetanus is high, 3%–95% depending on age, immune- and immunization-status, form of disease, and availability of proper medical care. The efficacy of tetanus toxoid vaccines was never formally studied, but cases in adequately vaccinated subjects are extremely rare and impact data (e.g. for NNT) convincingly show high vaccine effectiveness. WHO estimates that in 2018, 25,000 newborns died from NNT, an 88% reduction from the situation in 2000.

Disposal habits and microbial load of solid medical waste in sub-district healthcare facilities and households in Yilo-Krobo municipality, Ghana

The study aimed to assess disposal practices and quantify the microbial load present in SMW from ten sub-district level healthcare facilities and 385 households in Yilo Krobo municipality, Ghana. Disposal of solid medical waste (SMW) was assessed by questionnaire-based surveys, unstructured interviews and field observations. Microbiological analysis identified species and counts of bacteria present in SMW from both sources. Sociodemographic factors influencing the method of SMW disposal in households were evaluated using logistic regression analysis, with statistical significance set at p<0.05. Open burning (29%), burying (25%) and disposal at a dumpsite (49%) were common methods used by households to discard SMW. SMW disposal at a dumpsite was associated with age of respondents in households. Older people (50+ years) were three times more likely to place SMW in household waste later discarded at a dumpsite, compared to younger persons (20–30 years) [a0R, 95%CI = 3.37, 1.41–8.02]. In sub-district level healthcare facilities, open burning and burying were the most common methods used. Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa, Clostridium tetani, Enterococcus faecalis, Acinetobacter spp. Escherichia coli, Bacillus cereus and Enterococcus faecium) were bacteria identified in SMW recovered from both the healthcare facilities and the households. Klebsiella pneumoniae, Acinetobacter spp. and Clostridium tetani were found exclusively in untreated SMW generated in the healthcare facilities. Bacillus spp. and Pseudomonas spp. were found in one sample of treated SMW. The microbial load in SMW from healthcare facilities and households ranged from 0.036 x 103cfc/mg to 0.167 x 103 cfc/mg and from 0.118 x 103cfc/mg to 0.125 x 103cfc/mg respectively. This highlights the need for institutionalizing appropriate treatment methods in sub-district level facilities or strengthening the linkages with higher level facilities to ensure regular and adequate treatment of SMW. Public guidance on management of SMW generated in households which is context specific should also be provided.

Tétano: Ainda uma Ameaça: Relato de Caso Clínico

O tétano é uma doença potencialmente fatal, prevenível através da vacinação, causada por neurotoxinas produzidas pelo Clostridium tetani, que cessam a neurotransmissão inibitória. Apresenta uma tríade sintomática: rigidez, espasmos musculares e disfunção autonómica. A abordagem terapêutica é essencialmente sintomática, englobando: limpeza da ferida, sedação, bloqueio neuromuscular, suporte ventilatório e antibioterapia. Apresentamos o caso clínico de uma mulher de 79 anos, com vacina antitetânica desatualizada, admitida em contexto de ferida da face anterior do punho esquerdo, sem profilaxia com imunoglobulina antitetânica. Reavaliada na urgência 5 dias após o evento, com trismo, opistótono, falência respiratória e disautonomia. Procedeu-se a limpeza da ferida, administração de imunoglobulina e antibioterapia, sedação, ventilação mecânica e transferência para uma unidade de cuidados intensivos. Trata-se de um caso sem profilaxia, provavelmente evitável, mostrando a ameaça que o tétano representa, o que deve alertar os profissionais de saúde para a situação imunológica e cumprimento do plano nacional de vacinação.

Optimalisasi Waktu Inkubasi dan Konsentrasi Pepsin pada Aktivitas Produksi Serum Anti Tetanus

Tetanus merupakan penyakit yang disebabkan oleh kuman Clostridium tetani. Penyakit ini termasuk mematikan di negara berkembang. Melihat masih tingginya kasus tetanus di negara berkembang serta untuk memberikan pelayanan terbaik dan pengobatan efektif terhadap pasien yang terkena penyakit tetanus, maka diperlukan optimalisasi pada proses pembuatan serum anti tetanus, sehingga dapat meningkatkan kapasitas produksi dan kualitas serum yang dihasilkan. Berdasarkan latar belakang tersebut, penelitian ini bertujuan untuk mengetahui optimalisasi waktu inkubasi dan konsentrasi pepsin pada aktivitas produksi serum anti tetanus. Penelitian ini merupakan penelitian deskriptif kuantitatif dengan teknik pengumpulan data melalui observasi dan studi pustaka. Berdasarkan hasil analisis menggunakan software khusus densitometri Design of Experiment (DoE) dengan metode Sodium Dodecyl Sulphate Polyacrylamide Gel Elektroforesis (SDS PAGE) bahwa konsentrasi optimum didapatkan pada sampel anti tetanus ke-7 dengan konsentrasi pepsin sebesar 0,18 % dalam waktu inkubasi 5 jam.

Novel Small Molecule Inhibitors That Prevent the Neuroparalysis of Tetanus Neurotoxin

Tetanus neurotoxin (TeNT) is a protein exotoxin produced by Clostridium tetani that causes the deadly spastic neuroparalysis of tetanus. It consists of a metalloprotease light chain and of a heavy chain linked via a disulphide bond. TeNT binds to the neuromuscular junction (NMJ) and it is retro-axonally transported into vesicular compartments to the spinal cord, where it is released and taken up by inhibitory interneuron. Therein, the catalytic subunit is translocated into the cytoplasm where it cleaves its target protein VAMP-1/2 with consequent blockage of the release of inhibitory neurotransmitters. Vaccination with formaldehyde inactivated TeNT prevents the disease, but tetanus is still present in countries where vaccination coverage is partial. Here, we show that small molecule inhibitors interfering with TeNT trafficking or with the reduction of the interchain disulphide bond block the activity of the toxin in neuronal cultures and attenuate tetanus symptoms in vivo. These findings are relevant for the development of therapeutics against tetanus based on the inhibition of toxin molecules that are being retro-transported to or are already within the spinal cord and are, thus, not accessible to anti-TeNT immunoglobulins.

Autonomic instability in severe tetanus: a case report

Tetanus is an infectious disease of the nervous system caused by Clostridium tetani, and is characterized by tonic muscle contractions, painful spasms, and autonomic dysfunction. Severe autonomic dysfunction associated with tetanus can be life-threatening. We present a 62-year-old female who experienced lockjaw after an ankle fracture. The patient was diagnosed with tetanus and received tetanus immunoglobulin and a vaccination. The patient subsequently experienced labile hypertension. This case highlights the challenge and importance of managing cardiovascular instability.

The Reliability of Anamnestic Data in the Management of Clostridium Tetani Infection in Elderly

Background: Tetanus infection remains a significant complication of wounds. Because most tetanus treatment guidelines rely on anamnestic data collected directly from patients, the congruence between anamnesis and laboratory evidence must be verified, especially in the elderly population.Aim: Assess, in both the geriatric population (&gt;65) and the non-geriatric one, the reliability of anamnestic data for managing patients with tetanus-risk wounds, identified categories of populations most exposed to non-vaccination coverage, and assessed the agreement of the Tetanos Quick Stick (TQS) results with the therapy performed (administration of tetanus vaccine or immunoglobulin).Methods: In this retrospective single-center observational study, patients were asked their immunization status against tetanus vaccination. The decision to administer a vaccine or immunoglobulin was therefore clinical and based on anamnestic criteria. The TQS test was then given to patients who were unaware of their immunity status. Patients who thought they knew it but were not sure were given the TQS test to determine whether the anamnestic collection was supported by the test. The TQS test results were compared with the anamnestic data.Results: Most patients, geriatric and not geriatric, did not know their immune status. Among those who reported knowing their immune status, there was no agreement between the vaccine coverage declared by patients and the TQS test results (p &lt; 0.001), mainly in geriatric patients but also in the control group. Elderly and women had significantly lower positive TQS test results (p &lt; 0.001). There was a statistically significant discrepancy (p &lt; 0.001) between the therapy based on anamnestic data and the TQS test results.Conclusion: The reliability of anamnestic data for the management of patients with tetanus-risk wounds is low and decreases with age, becoming minimal in geriatric patients. Elderly and women are less likely to have an effective vaccination status against tetanus.

TÉTANO EM EQUINOS: UMA REVISÃO NARRATIVA

O tétano é uma doença grave que pode levar o animal a óbito, sendo provocada pela bactéria anaeróbica Clostridium tetani, que por sua vez libera toxinas que agem no sistema nervoso do animal, causando contração dos músculos, espasmos musculares contínuos, hiperexcitabilidade, entre outros problemas. O trabalho em questão objetiva elaborar uma revisão de literatura sobre o tétano em equinos, abrangendo aspectos relativos à epidemiologia, lesões, sintomas, tratamento e à profilaxia. A metodologia trata-se de um estudo descritivo revisional, verificando-se artigos científicos, teses, dissertações e livros publicados nos últimos 20 anos. Sendo assim, pode-se verificar que métodos de controle e medidas profiláticas podem reduzir significativamente o número de casos clínicos, bem como os prejuízos dos criadores em decorrência da possível morte do animal. Assim, recomendam-se cuidados especiais com os equinos, como, por exemplo, assistência veterinária, vacinação, higienização do local e dos instrumentos usados no manejo e em cirurgias.