Botulism mortality in the USA, 1975-2009

Underreporting or Failed Notification? Global Botulism Reporting, 2000-2022

Botulism is a rare, potentially fatal illness caused by botulinum toxins produced by Clostridium bacteria. There are no coordinated worldwide reporting mechanisms for botulism cases and therefore few reliable case frequency estimates. This study aimed to establish an international benchmark for case frequency to determine estimated global rates of underreporting of botulism cases. To this end, a comprehensive, multilingual search of major global and national databases, including gray data and government sources, was performed. Data from case series were pooled, standardized against United Nations midyear population estimates, and analyzed using Kolmogorov-Smirnov tests to identify normally distributed data series. National incidence rates of normally distributed series were compared with that of the United States, which was considered the gold standard due to its extensive data reported for 2004-2018. A total of 6,932 botulism cases from 59 nations were identified in the literature, with a global case fatality rate of 1.37%. The national mean incidence rate ranged from 0.00 to 8.04 cases per million people, with an international mean incidence rate of 0.62 cases per million people. At the continent level, incidence rates tended toward normal distributions, although few countries outside of North America and Europe exhibited normal distributions. Based on comparisons with the US standard, an estimated 88.71% of botulism cases worldwide were unreported in 2016. Better awareness of botulism among healthcare professionals, coordinated global reporting mechanisms, and research on additional contributing factors to underreporting would enable better understanding of global case frequency, thereby potentially reducing the global incidence of botulism and improving outcomes.

Foodborne Botulism, Canada, 2006-20211

During 2006-2021, Canada had 55 laboratory-confirmed outbreaks of foodborne botulism, involving 67 cases. The mean annual incidence was 0.01 case/100,000 population. Foodborne botulism in Indigenous communities accounted for 46% of all cases, which is down from 85% of all cases during 1990-2005. Among all cases, 52% were caused by botulinum neurotoxin type E, but types A (24%), B (16%), F (3%), and AB (1%) also occurred; 3% were caused by undetermined serotypes. Four outbreaks resulted from commercial products, including a 2006 international outbreak caused by carrot juice. Hospital data indicated that 78% of patients were transferred to special care units and 70% required mechanical ventilation; 7 deaths were reported. Botulinum neurotoxin type A was associated with much longer hospital stays and more time spent in special care than types B or E. Foodborne botulism often is misdiagnosed. Increased clinician awareness can improve diagnosis, which can aid epidemiologic investigations and patient treatment.

Infant Botulism, Israel, 2007-2021

Infant botulism (IB) is an intestinal toxemia that manifests as descending paralysis, constipation, and, in some cases, respiratory failure. Laboratory-confirmed IB cases are rare, and recent data in Israel are lacking. We conducted a national multicenter retrospective study of laboratory-confirmed IB cases reported in Israel during 2007-2021. A total of 8 cases were reported during the study period. During 2019-2021, incidence may have increased because of a cluster of 5 cases. Infant median age for diagnosis was 6.5 months, older than previously reported (3 months). Most cases occurred during March-July. Honey consumption was reported in 1 case, and possible environmental risk factors (living nearby rural or construction areas, dust exposure, and having a father who works as a farmer) were reported in 6 cases. Although IB is rare, its incidence in Israel may have increased over recent years, and its epidemiology and risk factors differ from cases reported previously in Israel.

Lambert-Eaton Myasthenic Syndrome and Botulism

PURPOSE OF REVIEW

This article reviews the pathophysiology, epidemiology, clinical features, diagnosis, and treatment of Lambert-Eaton myasthenic syndrome (LEMS) and botulism, presynaptic disorders of neuromuscular transmission in which rapid diagnosis improves long-term outcomes.

RECENT FINDINGS

Therapy for LEMS has seen significant advances in recent years due to the approval of amifampridine-based compounds. LEMS is likely still underdiagnosed, particularly when no underlying malignancy is identified. Clinicians must have a strong suspicion for LEMS in any patient presenting with proximal weakness and autonomic dysfunction. Botulism is another rare disorder of presynaptic neuromuscular transmission that is most commonly associated with improper storage or preservation of food products. Over the past 2 decades, wound botulism has been increasingly reported among users of black tar heroin. A high degree of clinical suspicion and electrodiagnostic studies can be beneficial in distinguishing botulism from other acute neurologic disorders, and early involvement of state and federal health authorities may assist in confirming the diagnosis and obtaining treatment. When botulism is suspected, electrodiagnostic studies can provide clinical evidence of disordered neuromuscular transmission in advance of serologic confirmation, and providers should not wait for confirmation of the diagnosis to initiate treatment.

SUMMARY

A targeted clinical history and a thorough neurologic examination with support from serologic and electrodiagnostic studies are key to early diagnosis of LEMS and botulism. Early diagnosis of both conditions creates opportunities for therapy and improves outcomes.

The key role of the ophthalmologist in diagnosing botulism: two case reports

Introduction

Botulinum toxin, the strongest known neurotoxin, is the cause of a rare fatal neuroparalytic disease characterized by the so-called "four Ds": diplopia, dysarthria, dysphagia, dry mouth. If left untreated, botulism may cause paralysis of the respiratory muscles, impairing the respiratory function which can ultimately lead to death.

Case report

We describe the cases of two patients who presented, two years apart, with similar ocular symptoms such as blurred vision due to accommodation palsy, diplopia, accompanied by xerostomia and swallowing disorders, which were further confirmed as botulism. Both cases had a similar clinical presentation of the intoxication and a positive response to treatment with botulinum antitoxin, while only the first case had a laboratory confirmation of the disease.

Conclusions

The key to diagnose botulism correctly is based on high clinical suspicion and requires a medical multidisciplinary approach and urgent specific treatment. Ophthalmology specialists must be aware of the disease, especially in cases in which ophthalmic manifestation appear at the onset.

Epidemiology and risk factors for notifiable Clostridium botulinum infections in Taiwan from 2003 to 2020

Botulinum toxin is produced by Clostridium botulinum, a gram-positive anaerobic bacterium. This study aimed to examine the epidemiological characteristics, including sex, age, season in which infection occurred, place of residence, and epidemiological trends, of confirmed botulism cases in Taiwan from 2003 to 2020. This study examined the annual summary data on reported botulism in Taiwan' s Center for Disease Control from 2003 to 2020 available to the public on the internet. We found that there were 50 confirmed domestic cases of botulism. The incidence of botulism ranged from 0 to 0.48 per 1000,000 from 2003 to 2020 and peaked in 2008 and 2010. During the 18-year investigation period in which 6-year intervals were used, the study results showed a decreasing trend (2003-2008, 2009-14, and 2015-2020, had 22, 19, 9 cases each). In terms of patients' gender, age, and place of residence, most of the patients were females (56%), were aged ≥ 50 years (48%), and resided in Taipei and northern Taiwan (44%). The number of botulism cases in Taiwan from 2012 to 2020 compared with other years (from 2003 to 2011) found that there were significant differences among patients within an age group of <20 years (P = .003, odds ratio = 18.500, and 95% confidence interval = 3.287-104.111), and there were significant differences among patients whose place of residence was Taipei metropolitan area (P = .025, odds ratio = 5.667, and 95% confidence interval = 1.248-25.734). During 2003 to 2009, there was no case of botulism among those aged <20 years. Over the last 10 years, botulism in children showed an increasing trend. A total of 9 children were found to have botulism during 2010 to 2020; most of these children were male (66.7%) and were infected during spring and summer (66.7%). This study is the first to report the number of confirmed domestic cases with botulism from surveillance data from Taiwan's Center for Disease Control during 2003 to 2020. This study also found that the place of residence and age were associated with an increased risk of botulism in Taiwan. This information may be useful for policymakers and clinical experts to direct prevention- and control-based activities regarding botulism that result in the most severe illness and the greatest burden on Taiwanese.

Foodborne botulism: A brief review of cases transmitted by cheese products (Review)

Food safety constitutes a basic priority for public health. Foodborne botulism occurs worldwide; it is an acute paralytic disease caused by the consumption of food containing the botulinum toxin. Growing consumer demand for cheese products could result in increased exposure of the population to this toxin, and thus the risk of foodborne botulism. The majority of cases of botulism caused by dairy products are related to cheese products specifically. Epidemic outbreaks and isolated cases have been reported over time. Domestically canned foods are still among the primary causes of the disease. Cheese products are not regularly involved in botulism incidents; it is however, necessary to take control measures for manufacturing and domestic preparation due to the high risk of occurrence of this particular disease. The aim of this review is to discuss foodborne botulism caused by cheese products, providing a brief epidemiological history, and to examine certain control measures that should be taken throughout the production process to better protect public health.

Use of Crystallography and Molecular Modeling for the Inhibition of the Botulinum Neurotoxin A Protease

Botulinum neurotoxins (BoNTs) are extremely toxic and have been deemed a Tier 1 potential bioterrorism agent. The most potent and persistent of the BoNTs is the "A" serotype, with strategies to counter its etiology focused on designing small-molecule inhibitors of its light chain (LC), a zinc-dependent metalloprotease. The successful structure-based drug design of inhibitors has been confounded as the LC is highly flexible with significant morphological changes occurring upon inhibitor binding. To achieve greater success, previous and new cocrystal structures were evaluated from the standpoint of inhibitor enantioselectivity and their effect on active-site morphology. Based upon these structural insights, we designed inhibitors that were predicted to take advantage of π-π stacking interactions present in a cryptic hydrophobic subpocket. Structure-activity relationships were defined, and X-ray crystal structures and docking models were examined to rationalize the observed potency differences between inhibitors.

A summary of surveillance, morbidity and microbiology of laboratory-confirmed cases of infant botulism in Canada, 1979-2019

Background

Infant botulism is a rare toxicoinfectious disease caused by colonization of the infant's intestine with botulinum neurotoxin-producing clostridia (i.e. Clostridium botulinum or neurotoxigenic strains of C. butyricum or C. baratii). Our goal was to examine data from laboratory-confirmed cases of infant botulism reported in Canada to summarize incidence over time, over geographic distribution by province or territory, and by sex, and to compare these parameters with data from the Canadian Notifiable Disease Surveillance System (CNDSS). The average age of onset, serotype of botulinum neurotoxin (BoNT), case outcomes, length of hospitalization and suitability of clinical specimens for laboratory confirmation were also determined.

Methods

We examined laboratory records from the Health Canada Botulism Reference Service and the British Columbia Centre for Disease Control (BCCDC) Public Health Laboratory. The Discharge Abstract Database (DAD) and the Hospital Morbidity Database (HMDB) of the Canadian Institute of Health Information (CIHI) were queried for data on hospitalization of infant botulism cases. The CNDSS was queried for data on reported cases of infant botulism.

Results

From 1979 to 2019, 63 laboratory-confirmed cases of infant botulism were confirmed by the Health Canada Botulism Reference Service and the BCCDC Public Health Laboratory for an annual rate of 4.30 cases per million live births. From 1983 to 2018, 57 cases of infant botulism were reported to the CNDSS. Of the 63 cases confirmed by the reference laboratories, the median age of onset was 16 weeks with a range of 2 to 52 weeks. The majority of cases were type A (76%) and B (21%), with single cases of type F and type AB. Of the 23 laboratory-confirmed cases with matched hospital records, 13 were transferred to special care and eight needed ventilator support; no deaths were reported.

Conclusion

Spores of C. botulinum are present naturally in the environment, thus diagnosis of infant botulism does not require a history of exposure to high-risk foods such as honey. Stool samples are the most useful diagnostic specimen.

Irreversible inhibition of BoNT/A protease: proximity-driven reactivity contingent upon a bifunctional approach

Botulinum neurotoxin A (BoNT/A) is categorized as a Tier 1 bioterrorism agent and persists within muscle neurons for months, causing paralysis. A readily available treatment that abrogates BoNT/A's toxicity and longevity is a necessity in the event of a widespread BoNT/A attack and for clinical treatment of botulism, yet remains an unmet need. Herein, we describe a comprehensive warhead screening campaign of bifunctional hydroxamate-based inhibitors for the irreversible inhibition of the BoNT/A light chain (LC). Using the 2,4-dichlorocinnamic hydroxamic acid (DCHA) metal-binding pharmacophore modified with a pendent warhead, a total of 37 compounds, possessing 13 distinct warhead types, were synthesized and evaluated for time-dependent inhibition against the BoNT/A LC. Iodoacetamides, maleimides, and an epoxide were found to exhibit time-dependent inhibition and their k GSH measured as a description of reactivity. The epoxide exhibited superior time-dependent inhibition over the iodoacetamides, despite reacting with glutathione (GSH) 51-fold slower. The proximity-driven covalent bond achieved with the epoxide inhibitor was contingent upon the vital hydroxamate-Zn2+ anchor in placing the warhead in an optimal position for reaction with Cys165. Monofunctional control compounds exemplified the necessity of the bifunctional approach, and Cys165 modification was confirmed through high-resolution mass spectrometry (HRMS) and ablation of time-dependent inhibitory activity against a C165A variant. Compounds were also evaluated against BoNT/A-intoxicated motor neuron cells, and their cell toxicity, serum stability, and selectivity against matrix metalloproteinases (MMPs) were characterized. The bifunctional approach allows the use of less intrinsically reactive electrophiles to intercept Cys165, thus expanding the toolbox of potential warheads for selective irreversible BoNT/A LC inhibition. We envision that this dual-targeted strategy is amenable to other metalloproteases that also possess non-catalytic cysteines proximal to the active-site metal center.

Safety, Tolerability, and Pharmacokinetics of NTM-1632, a Novel Mixture of Three Monoclonal Antibodies against Botulinum Toxin B

Botulism is a rare, life-threatening paralytic disease caused by Clostridium botulinum neurotoxin (BoNT). Available treatments, including an equine antitoxin and human immune globulin, are given postexposure and challenging to produce and administer. NTM-1632 is an equimolar mixture of 3 human IgG monoclonal antibodies, B1, B2, and B3, targeting BoNT serotype B (BoNT/B). This first-in-human study assessed the safety, tolerability, pharmacokinetics (PK), and immunogenicity of NTM-1632. This double-blind, single-center, placebo-controlled dose escalation study randomized 3 cohorts of healthy volunteers to receive a single intravenous dose of NTM-1632 (0.033, 0.165, or 0.330 mg/kg) or saline placebo. Safety monitoring included physical examinations, clinical laboratory studies, and vital signs. Blood sampling was performed at prespecified time points for PK and immunogenicity analyses. Twenty-four subjects received study product (18 NTM-1632; 6 placebo), and no deaths or serious adverse events were reported. Adverse events in the NTM-1632 groups were generally mild and similar in frequency and severity to the placebo group, and no safety signal was identified. NTM-1632 has a favorable PK profile with a half-life of >20 days for the 0.330-mg/kg dose and an approximately linear relationship with respect to maximum concentration and area under the concentration-time curve (AUC_0→t). NTM-1632 demonstrated low immunogenicity with only a few treatment-emergent antidrug antibody responses in the low and middle dosing groups and none at the highest dose. NTM-1632 is well tolerated at the administered doses. The favorable safety, PK, and immunogenicity profile of NTM-1632 supports further clinical development as a treatment for BoNT/B intoxication and postexposure prophylaxis. (This study has been registered at ClinicalTrials.gov under identifier NCT02779140.).

A Case Report of Wound Botulism - Rare Disease on the Rise with the Opioid Crisis

Wound botulism is a rare, underrecognized life-threatening illness caused by a toxin produced by Clostridium botulinum, a spore-forming anaerobic bacterium. Approximately 20 cases are reported in the United States each year, mostly from California. Most wound botulism cases occur in drug injectors, particularly among those using black tar heroin. The initial presentation of botulism may overlap with other diagnoses, including opioid intoxication and pre-existing neurological disease, making accurate diagnosis difficult. A healthy 40-year-old patient with a history of injecting black tar heroin presented to an emergency department complaining of generalized weakness and throat discomfort. He was given antibiotics and was sent home. The next day, the patient presented to another emergency department with additional complaints of slurred speech and blurring of vision. He was admitted for a possible cerebrovascular injury. In the absence of positive findings from laboratory or imaging studies, botulism was considered. The patient decompensated and was intubated. Botulism antitoxin was given, and the patient eventually recovered. Prompt decision-making based on clinical suspicion and an informed presumptive diagnosis, administration of botulism antitoxin, and aggressive provision of supportive care can arrest the progression of paralysis and be life-saving. With the rise of opioid use in the United States, leading to a reversion to heroin as a cheaper form of opioids, cases of wound botulism may be on the rise. Clinician attentiveness to obtaining substance history and being aware of botulism presentation may lead to life-saving treatments for these patients.

Early recovery of botulism: one decade of experience

BACKGROUND

Botulism is a rare but serious disease, which appears in different forms. In this study, we reviewed the clinical features, laboratory data, and outcomes of patients who referred to our tertiary center.

MATERIALS AND METHODS

All confirmed cases of botulism referred to an academic referral center and a teaching hospital during 2009-2019, were retrospectively reviewed.

RESULTS

Fifty-three cases of clinical or laboratory-confirmed botulism were examined in this study. Nineteen patients were confirmed by laboratory data (serotype A (89.5%) and serotype E (10.5%)). In seven cases, the cause of botulism was unclear. In two patients, systemic symptoms emerged after the therapeutic injection of botulinum neurotoxin. The majority of cases (83%) were caused by an obvious food source. In 66% of cases, the initial symptoms emerged within less than 36 h, while in 20.8% of cases, the symptoms developed within or after 36 h; however, in seven patients that their botulism sources were unclear, the onset could not be estimated. All patients showed cranial involvement and generalized manifestation, and 49.1% had gastrointestinal symptoms. Except for two patients who were not treated due to immediate drug reactions who manifested severe hemodynamic instability, the rest of the patients were treated with trivalent antitoxin (A, B, and E). The complete resolution of the symptoms during hospitalization was documented in 50.9% of the patients. About 17% of the patients were intubated. Two patients died due to massive bilateral pulmonary thromboembolism and cardiac asystole following respiratory failure.

CONCLUSIONS

Although the complete resolution of the symptoms usually takes several weeks, in our experience, most patients showed at least partial resolution upon discharge. Early treatment results in better outcomes.

Dysphagia Alone as a Unique Presentation of Wound Botulism in the Emergency Department: A Case Report

INTRODUCTION

Wound botulism is a rare and potentially fatal infectious disease, often seen in patients who abuse injection drugs. It classically presents with dysfunction of bilateral cranial nerves followed by proximal and distal motor weakness, which can progress to respiratory failure.

CASE REPORT

We report a case of a 31-year-old female who presented to the emergency department for the fifth time with an eight-day history of isolated dysphagia without any other neurologic symptoms. She reported a history of injection drug abuse via "skin popping," was admitted to the hospital, and ultimately diagnosed with wound botulism.

CONCLUSION

This case exemplifies the diagnostic pitfalls of rare diseases such as wound botulism and provides insight regarding the diagnosis and treatment of this entity. This case also highlights the unique medical and social challenges emergency physicians face while trying to reliably evaluate patients who abuse controlled substances.

Vaccine Production to Protect Animals Against Pathogenic Clostridia

Clostridium is a broad genus of anaerobic, spore-forming, rod-shaped, Gram-positive bacteria that can be found in different environments all around the world. The genus includes human and animal pathogens that produce potent exotoxins that cause rapid and potentially fatal diseases responsible for countless human casualties and billion-dollar annual loss to the agricultural sector. Diseases include botulism, tetanus, enterotoxemia, gas gangrene, necrotic enteritis, pseudomembranous colitis, blackleg, and black disease, which are caused by pathogenic Clostridium. Due to their ability to sporulate, they cannot be eradicated from the environment. As such, immunization with toxoid or bacterin-toxoid vaccines is the only protective method against infection. Toxins recovered from Clostridium cultures are inactivated to form toxoids, which are then formulated into multivalent vaccines. This review discusses the toxins, diseases, and toxoid production processes of the most common pathogenic Clostridium species, including Clostridiumbotulinum, Clostridiumtetani, Clostridiumperfringens, Clostridiumchauvoei, Clostridiumsepticum, Clostridiumnovyi and Clostridiumhemolyticum.

Safety and Improved Clinical Outcomes in Patients Treated With New Equine-Derived Heptavalent Botulinum Antitoxin

Background

Botulism is a rare, life-threatening paralytic illness. Equine-derived heptavalent botulinum antitoxin (HBAT), the only currently available treatment for noninfant botulism in the United States, was licensed in 2013. No reports have systematically examined safety and clinical benefit of HBAT among botulism patients.

Methods

From March 2010 through March 2013, we collected data prospectively and through medical record reviews of patients with confirmed or suspected botulism who were treated with HBAT under an expanded-access Investigational New Drug program.

Results

Among 249 HBAT-treated patients, 1 (<1%) child experienced an HBAT-related serious adverse event (hemodynamic instability characterized by bradycardia, tachycardia, and asystole); 22 (9%) patients experienced 38 nonserious adverse events reported by physicians to be HBAT related. Twelve (5%) deaths occurred; all were determined to be likely unrelated to HBAT. Among 104 (42%) patients with confirmed botulism, those treated early (≤2 days) spent fewer days in the hospital (median, 15 vs 25 days; P < .01) and intensive care (10 vs 17 days; P = .04) than those treated later. Improvements in any botulism sign/symptom were detected a median of 2.4 days and in muscle strength a median of 4.8 days after HBAT.

Conclusions

HBAT was safe and provided clinical benefit in treated patients. HBAT administration within 2 days of symptom onset was associated with shorter hospital and intensive care stays. These results highlight the importance of maintaining clinical suspicion for botulism among patients presenting with paralytic illness to facilitate early HBAT treatment before laboratory confirmation might be available. Clinical consultation and, if indicated, HBAT release, are available to clinicians 24/7 through their state health department in conjunction with CDC.

Botulinum Neurotoxin Detection Methods for Public Health Response and Surveillance

Botulism outbreak due to consumption of food contaminated with botulinum neurotoxins (BoNTs) is a public health emergency. The threat of bioterrorism through deliberate distribution in food sources and/or aerosolization of BoNTs raises global public health and security concerns due to the potential for high mortality and morbidity. Rapid and reliable detection methods are necessary to support clinical diagnosis and surveillance for identifying the source of contamination, performing epidemiological analysis of the outbreak, preventing and responding to botulism outbreaks. This review considers the applicability of various BoNT detection methods and examines their fitness-for-purpose in safeguarding the public health and security goals.

Substrate cleavage and duration of action of botulinum neurotoxin type FA ("H, HA")

Botulinum neurotoxin (BoNT) type FA is the only known naturally occurring chimeric BoNT of domains of BoNT/A and BoNT/F. BoNT/FA consists of an F5-like light chain (LC), a unique heavy chain (HC) translocation domain, and a HC receptor binding domain similar to BoNT/A1. Previous analyses of purified BoNT/FA have indicated a 5-10-fold greater potency in cultured human or rat neurons as compared to BoNT/A1 and a 400-500-fold greater potency compared to BoNT/B1. However, in vivo potency in mice was about 5-fold lower than BoNT/A1 or/B1. In this report, species specificity was examined by cell-based assays using primary neurons from mice and examining VAMP1 and 2 cleavage. The data indicated similar potency of BoNT/FA in primary mouse spinal cord neurons as previously observed in primary rat and human induced pluripotent stem cell (hiPSC) derived neuronal cell models, and equal enzymatic cleavage of mouse VAMP1 and 2 isoforms. Since the duration of action of BoNTs is due to continuous enzymatic activity of the LC in the neuronal cytosol, BoNT/FA was expected to have a short duration of action due to its F-type LC. In this report the duration of action of BoNT/FA was compared to that of BoNT/F1,/F5, and/B1 in both hiPSC derived neurons and in the in vivo mouse model. The data indicate a duration of action of BoNT/FA similar to BoNT/B1, while BoNT/F5 had a short duration of action similar to BoNT/F1.