Mucocutaneous Manifestations of Recreational Drug Use

Recreational drug use is increasingly common in the dermatology patient population and is often associated with both general and specific mucocutaneous manifestations. Signs of substance use disorder may include changes to general appearance, skin, and mucosal findings associated with particular routes of drug administration (injection, insufflation, or inhalation) or findings specific to a particular drug. In this review article, we provide an overview of the mucocutaneous manifestations of illicit drug use including cocaine, methamphetamine, heroin, hallucinogens, marijuana, and common adulterants to facilitate the identification and improved care of these patients with the goal being to connect this patient population with appropriate resources for treatment.

One Health Assessment of Bacillus anthracis Incidence and Detection in Anthrax-Endemic Areas of Pakistan

Anthrax, a severe zoonotic disease, is infrequently reported in anthrax-endemic regions of Pakistan. Despite clinical reports indicating its presence, particularly cutaneous anthrax, there is insufficient laboratory evidence regarding disease occurrence and environmental persistence. The present study aimed to confirm Bacillus anthracis presence, accountable for animal mortality and human infection, while exploring environmental transmission factors. Between March 2019 and July 2021, a total of 19 outbreaks were documented. Of these, 11 affected sheep/goats in Zhob district and 8 affected cattle/sheep in Bajour Agency. Clinical signs suggestive of Bacillus anthracis outbreak were observed in 11 animals. Blood and swab samples were collected for confirmation. The study followed a One Health approach, analyzing animal, environmental (soil/plant), and human samples. Of the 19 outbreaks, 11 were confirmed positive for anthrax based on growth characteristics, colony morphology, and PCR. Soil and plant root samples from the outbreak areas were collected and analyzed microscopically and molecularly. Cutaneous anthrax was observed in six humans, and swab samples were taken from the lesions. Human serum samples (n = 156) were tested for IgG antibodies against PA toxin and quantitative analysis of anthrax toxin receptor 1 (ANTXR1). Bacillus anthracis was detected in 65 out of 570 (11.40%) soil samples and 19 out of 190 (10%) plant root samples from the outbreak areas. Four out of six human samples from cutaneous anthrax lesions tested positive for Bacillus anthracis. Human anthrax seroprevalence was found to be 11% and 9% in two districts, with the highest rates among butchers and meat consumers. The highest ANTXR1 levels were observed in butchers, followed by meat consumers, farm employees, meat vendors, veterinarians, and farm owners. These findings highlight the persistence of anthrax in the region and emphasize the potential public health risks.

Whole genome sequencing of Bacillus anthracis isolated from animal in the 1960s, Brazil, belonging to the South America subclade

Bacillus anthracis causes anthrax disease and can affect humans and other animals. This zoonotic disease has an impact on the economic and health aspects. B. anthracis population is divided into three major clades: A (with worldwide distribution), B, and C (restricted to specific regions). Anthrax is most common in agricultural regions of central and southwestern Asia, sub-Saharan Africa, Southern and Eastern Europe, the Caribbean, and Central and South America. Here, we sequenced by short and long reads technologies to generate a hybrid assembly of a lineage of B. anthracis recovered from animal source in the 1960s in Brazil. Isolate identification was confirmed by phenotypic/biochemical tests and MALDI-TOF MS. Antimicrobial susceptibility was performed by in-house broth microdilution. B. anthracis IAL52 was susceptible to penicillin, amoxicillin, doxycycline, levofloxacin, and tetracycline but non-susceptible to ciprofloxacin. IAL52 was classified as sequence type ST2, clade A.Br.069 (V770 group). Sequencing lineages of B. anthracis, especially from underrepresented regions, can help determine the evolution of this critical zoonotic and virulent pathogen.

An Outbreak of Human Systemic Anthrax, including One Case of Anthrax Meningitis, Occurred in Calabria Region (Italy): A Description of a Successful One Health Approach

In this report, three cases of human cutaneous anthrax are described, one complicated by meningitis, and all were linked to a single infected bullock. A 41-year-old male truck driver, along with two male slaughterhouse workers, 45 and 42, were hospitalized for necrotic lesions of the arm associated with edema of the limb and high fever. All three patients were involved in transporting a bullock to the slaughterhouse. Microbiological examination on the prescapular lymph node and a piece of muscle from the bullock carcass showed the presence of Bacillus anthracis. The three patients underwent a biopsy of the affected tissues, and all samples tested positive for B. anthracis DNA using PCR. Furthermore, the truck driver also complained of an intense headache, and a CSF sampling was performed, showing him positive for B. anthracis by PCR, confirming the presumptive diagnosis of meningitis. Fast diagnosis and appropriate treatment are crucial for the management of human anthrax. Cooperation between human and veterinary medicine proved successful in diagnosing and resolving three human anthrax cases, confirming the reliability of the One Health approach for the surveillance of zoonoses.

Ten years of weekly epidemiological teleconference (EpiLag) - an effective and time-efficient tool for infectious disease event information, Germany, 2009-2018

In 2009, the Robert Koch Institute (RKI) and the 16 German federal state public health authorities (PHAs) established a weekly epidemiological teleconference (EpiLag) to discuss infectious disease (ID) events and foster horizontal and vertical information exchange. We present the procedure, discussed ID topics and evaluation results of EpiLag after 10 years. We analysed attendance, duration of EpiLag and the frequency of reported events. Participants (RKI and state PHA) were surveyed regarding their satisfaction with logistics, contents and usefulness of EpiLag (Likert scales). Between 2009 and 2018, RKI hosted 484 EpiLag conferences with a mean duration of 25 min (range: 4–60) and high participation (range: 9–16; mean: 15 PHAs). Overall, 2975 ID events (39% international, 9% national and 52% subnational) were presented (mean: 6.1 per EpiLag), most frequently on measles (18%), salmonellosis (8%) and influenza (5%). All responding participants (14/16 PHAs and 9/9 at RKI) were satisfied with the EpiLag's organization and minutes and deemed EpiLag useful for an overview and information distribution on ID events relevant to Germany. EpiLag is time efficient, easily applicable and useful for a low-threshold event communication. It supports PHAs in crises and strengthens the network of surveillance stakeholders. We recommend its implementation to other countries or sectors.

Approach to the Patient with a Skin and Soft Tissue Infection

The diagnosis of a skin and soft tissue infection (SSTI) requires careful attention to a patient's history, physical examination, and diagnostic test results. We review for many bacterial, viral, fungal, and parasitic pathogens that cause SSTIs the clues for reaching a diagnosis, including reported past medical history, hobbies and behaviors, travel, insect bites, exposure to other people and to animals, environmental exposures to water, soil, or sand, as well as the anatomic site of skin lesions, their morphology on examination, and their evolution over time. Laboratory and radiographic tests are discussed that may be used to confirm a specific diagnosis.

Case Report of an Injectional Anthrax in France, 2012

(1) Background: Bacillus anthracis is a spore-forming, Gram-positive bacterium causing anthrax, a zoonosis affecting mainly livestock. When occasionally infecting humans, B. anthracis provokes three different clinical forms: cutaneous, digestive and inhalational anthrax. More recently, an injectional anthrax form has been described in intravenous drug users. (2) Case presentation: We report here the clinical and microbiological features, as well as the strain phylogenetic analysis, of the only injectional anthrax case observed in France so far. A 27-year-old patient presented a massive dermohypodermatitis with an extensive edema of the right arm, and the development of drug-resistant shocks. After three weeks in an intensive care unit, the patient recovered, but the microbiological identification of B. anthracis was achieved after a long delay. (3) Conclusions: Anthrax diagnostic may be difficult clinically and microbiologically. The phylogenetic analysis of the Bacillus anthracis strain PF1 confirmed its relatedness to the injectional anthrax European outbreak group-II.

Review: The risk of contracting anthrax from spore-contaminated soil - A military medical perspective

Anthrax is an infectious disease of relevance for military forces. Although spores of Bacillus anthracis obiquitously occur in soil, reports on soil-borne transmission to humans are scarce. In this narrative review, the potential of soil-borne transmission of anthrax to humans is discussed based on pathogen-specific characteristics and reports on anthrax in the course of several centuries of warfare. In theory, anthrax foci can pose a potential risk of infection to animals and humans if sufficient amounts of virulent spores are present in the soil even after an extended period of time. In praxis, however, transmissions are usually due to contacts with animal products and reported events of soil-based transmissions are scarce. In the history of warfare, even in the trenches of World War I, reported anthrax cases due to soil-contaminated wounds are virtually absent. Both the perspectives and the experience of the Western hemisphere and of former Soviet Republics are presented. Based on the accessible data as provided in the review, the transmission risk of anthrax by infections of wounds due to spore-contaminated soil is considered as very low under the most circumstance. Active historic anthrax foci may, however, still pose a risk to the health of deployed soldiers.

Toxin-neutralizing antibodies elicited by naturally acquired cutaneous anthrax are elevated following severe disease and appear to target conformational epitopes

Understanding immune responses to native antigens in response to natural infections can lead to improved approaches to vaccination. This study sought to characterize the humoral immune response to anthrax toxin components, capsule and spore antigens in individuals (n = 46) from the Kayseri and Malatya regions of Turkey who had recovered from mild or severe forms of cutaneous anthrax infection, compared to regional healthy controls (n = 20). IgG antibodies to each toxin component, the poly-γ-D-glutamic acid capsule, the Bacillus collagen-like protein of anthracis (BclA) spore antigen, and the spore carbohydrate anthrose, were detected in the cases, with anthrax toxin neutralization and responses to Protective Antigen (PA) and Lethal Factor (LF) being higher following severe forms of the disease. Significant correlative relationships among responses to PA, LF, Edema Factor (EF) and capsule were observed among the cases. Though some regional control sera exhibited binding to a subset of the tested antigens, these samples did not neutralize anthrax toxins and lacked correlative relationships among antigen binding specificities observed in the cases. Comparison of serum binding to overlapping decapeptides covering the entire length of PA, LF and EF proteins in 26 cases compared to 8 regional controls revealed that anthrax toxin-neutralizing antibody responses elicited following natural cutaneous anthrax infection are directed to conformational epitopes. These studies support the concept of vaccination approaches that preserve conformational epitopes.

BA3338, a surface layer homology domain possessing protein augments immune response and protection efficacy of protective antigen against Bacillus anthracis in mouse model

AIM

Category A classified Bacillus anthracis is highly fatal pathogen that causes anthrax and creates challenges for global security and public health. In this study, development of a safe and ideal next-generation subunit anthrax vaccine has been evaluated in mouse model.

METHOD AND RESULTS

Protective antigen (PA) and BA3338, a surface layer homology (SLH) domain possessing protein were cloned, expressed in heterologous system and purified by IMAC. Recombinant PA and BA3338 with alum were administered in mouse alone or in combination. The humoral and cell-mediated immune response was measured by ELISA and vaccinated animals were challenged with B. anthracis spores via intraperitoneal route. The circulating IgG antibody titre of anti-PA and anti-BA3338 was found significantly high in the first and second booster sera. A significant enhanced level of IL-4, IFN-γ and IL-12 was observed in antigens stimulated supernatant of splenocytes of PA + BA3338 vaccinated animals. A combination of PA and BA3338 provided 80% protection against 20 LD₅₀ lethal dose of B. anthracis spores.

CONCLUSION

Both antigens induced admirable humoral and cellular immune response as well as protective efficacy against B. anthracis spores.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has been evaluated for the first time using BA3338 as a vaccine candidate alone or in combination with well-known anthrax vaccine candidate PA. The findings of this study demonstrated that BA3338 could be a co-vaccine candidate for development of dual subunit vaccine against anthrax.

Accurate and selective quantification of anthrax protective antigen in plasma by immunocapture and isotope dilution mass spectrometry

Anthrax protective antigen (83 kDa, PA83) is an essential component of two major binary toxins produced by Bacillus anthracis, lethal toxin (LTx) and edema toxin (ETx). During infection, LTx and ETx contribute to immune collapse, endothelial dysfunction, hemorrhage and high mortality. Following protease cleavage on cell receptors or in circulation, the 20 kDa (PA20) N-terminus is released, activating the 63 kDa (PA63) form which binds lethal factor (LF) and edema factor (EF), facilitating their entry into their cellular targets. Several ELISA-based PA methods previously developed are primarily qualitative or semi-quantitative. Here, we combined protein immunocapture, tryptic digestion and isotope dilution liquid chromatography-mass spectrometry (LC-MS/MS), to develop a highly selective and sensitive method for detection and accurate quantification of total-PA (PA83 + PA63) and PA83. Two tryptic peptides in the 63 kDa region measure total-PA and three in the 20 kDa region measure PA83 alone. Detection limits range from 1.3-2.9 ng mL-1 PA in 100 μL of plasma. Spiked recovery experiments with combinations of PA83, PA63, LF and EF in plasma showed that PA63 and PA83 were quantified accurately against the PA83 standard and that LF and EF did not interfere with accuracy. Applied to a study of inhalation anthrax in rhesus macaques, total-PA suggested triphasic kinetics, similar to that previously observed for LF and EF. This study is the first to report circulating PA83 in inhalation anthrax, typically at less than 4% of the levels of PA63, providing the first evidence that activated PA63 is the primary form of PA throughout infection.

Evaluation of in vitro antimicrobial susceptibility of Bacillus anthracis strains isolated during anthrax outbreaks in Italy from 1984 to 2017

Anthrax, caused by Bacillus anthracis, is a non-contagious infectious disease that affects a wide range of animal species (primarily ruminants) including humans. Due to the often-fatal outcome in humans, quick administration of definitely effective antimicrobials is crucial either as prophylaxis or as a clinical case therapy. In this study, 110 B. anthracis strains, temporally, geographically, and genetically different, isolated during anthrax outbreaks in Italy from 1984 to 2017, were screened using a broth microdilution method to determine their susceptibility to 16 clinically relevant antimicrobial agents. The strains were isolated from various matrices (human, animal, and environmental samples) and were representative of thirty distinct genotypes previously identified by 15-loci multiple-locus variable-number of tandem repeats analysis. The antimicrobials tested were gentamicin, ceftriaxone, streptomycin, penicillin G, clindamycin, chloramphenicol, vancomycin, linezolid, cefotaxime, tetracycline, erythromycin, rifampin, amoxicillin, ciprofloxacin, doxycycline, and trimethoprim. All isolates were susceptible to most of the tested antimicrobials, with the exception of trimethoprim for which all of them showed high minimal inhibitory concentration values. An intermediate level of susceptibility was recorded for ceftriaxone and cefotaxime. Although the Centers for Disease Control and Prevention recommend the use of doxycycline, ciprofloxacin, penicillin G, and amoxicillin for treatment of human cases and for post-exposure prophylaxis to anthrax spores, this study shows a high degree of in vitro susceptibility of B. anthracis to many other antimicrobials, suggesting the possibility of an alternative choice for prophylaxis and therapy.

Genetic characteristics of Bacillus anthracis isolated from northwestern China from 1990 to 2016

Anthrax is a global re-emerging zoonotic disease and is an endemic disease in China, especially in rural regions. In this study, the general characteristics of human anthrax outbreaks that occurred in areas of northwestern China over the past decade have been described. Meanwhile, the genetic characteristics of Bacillus anthracis isolated from these areas from 1990 to 2016 were analyzed by means of canonical single-nucleotide polymorphism (canSNP) analysis and multilocus variable-number tandem repeat analysis (MLVA) with 15 markers. Five sublineages/subgroups, namely, A.Br.001/002, A.Br.Vollum, A.Br.Aust94, A.Br.Ames and A.Br.008/009, were detected by using 13 canSNP sites. All of the sublineages were found in Xinjiang province, while one sublineage was found in Shaanxi, two in Gansu, three in Qinghai and four in Inner Mongolia. However, the geographical distribution of the B. anthracis populations exhibited different canSNP characteristics from those of the strains isolated before 1990 in China. In contrast to previous data, the A.Br.Ames subgroup was also observed to be scattered from Inner Mongolia to other provinces. All 106 strains were assigned to 36 MLVA15 genotypes, and 21 of these types were first observed in this study. The strains collected from anthrax outbreaks in recent decade were classified as subgroups A.Br.001/002 and A.Br.Ames and identified as genotypes MLVA15-28, MLVA15-30, MLVA15-31, MLVA15-38, MLVA15-CHN3, and MLVA15-CHN18. By canSNP analysis and MLVA, we found that the diversification of MLVA genotypes and the geographical distribution of B. anthracis populations is gradually becoming balanced across northwestern China. This study also provides preliminary survey results regarding the population diversity of B. anthracis in China, which will help promote the prevention and control of this important disease.

In this study, the general characteristics of human anthrax outbreaks that occurred in northwestern China over the past decade were described. Meanwhile, the genetic characteristics of Bacillus anthracis isolated from these areas from 1990 to 2016 were analyzed with the canSNP and MLVA15 methods. Our results showed a diversity of MLVA genotypes. We also observed gradual balancing of the geographical distribution of B. anthracis population in northwestern China according to the canSNP analysis. In particular, the A.Br.Ames subgroup now seems to be scattered from Inner Mongolia to other provinces, in contrast to the data before 1990. This study also provides preliminary survey results on the population diversity of B. anthracis in China, which will help to promote the prevention and control of this important disease.

Drumming-associated anthrax incidents: exposures to low levels of indoor environmental contamination

Two fatal drumming-related inhalational anthrax incidents occurred in 2006 and 2008 in the UK. One individual was a drum maker and drummer from the Scottish Borders, most likely infected whilst playing a goat-skin drum contaminated with Bacillus anthracis spores; the second, a drummer and drum maker from East London, likely became infected whilst working with contaminated animal hides.

We have collated epidemiological and environmental data from these incidents and reviewed them alongside three similar contemporaneous incidents in the USA. Sampling operations recovered the causative agent from drums and drum skins and from residences and communal buildings at low levels. From these data, we have considered the nature of the exposures and the number of other individuals likely to have been exposed, either to the primary infection events or to subsequent prolonged environmental contamination (or both).

Despite many individual exposures to widespread low-level spore contamination in private residences and in work spaces for extended periods of time (at least 1 year in one instance), only one other individual acquired an infection (cutaneous). Whilst recognising the difficulty in making definitive inferences from these incidents to specific residual contamination levels, and by extending the risk to public health, we believe it may be useful to reflect on these findings when considering future incident management risk assessments and decisions in similar incidents that result in low-level indoor contamination.

Treating Anthrax-Induced Meningitis in Rabbits

Treatment of anthrax is challenging, especially during the advanced stages of the disease. Recently, the Centers for Disease Control and Prevention (CDC) updated its recommendations for postexposure prophylaxis and treatment of exposed populations (before and after symptom onset). These recommendations distinguished, for the first time, between systemic disease with and without meningitis, a common and serious complication of anthrax. The CDC considers all systemic cases meningeal unless positively proven otherwise. The treatment of patients suffering from systemic anthrax with suspected or confirmed meningitis includes the combination of three antibiotics, i.e., a fluoroquinolone (levofloxacin or ciprofloxacin), a β-lactam (meropenem or imipenem), and a protein synthesis inhibitor (linezolid or clindamycin). In addition, treatment with an antitoxin (anti-protective antigen antibodies) and dexamethasone should be applied. Since the efficacy of most of these treatments has not been demonstrated, especially in animal meningitis models, we developed an anthrax meningitis model in rabbits and tested several of these recommendations. We demonstrated that, in this model, ciprofloxacin, linezolid, and meropenem were ineffective as single treatments, while clindamycin was highly effective. Furthermore, combined treatments of ciprofloxacin and linezolid or ciprofloxacin and dexamethasone failed in treating rabbits with meningitis. We demonstrated that dexamethasone actually hindered blood-brain barrier penetration by antibiotics, reducing the effectiveness of antibiotic treatment of anthrax meningitis in this rabbit model.

Nodular Lymphangitis (Sporotrichoid Lymphocutaneous Infections). Clues to Differential Diagnosis

Nodular lymphangitis, also known as sporotrichoid lymphocutaneous infections, is characterized by suppurative inflammatory nodules along the lymphatic vessels. This manifestation is classic of sporotrichosis, however, other infections such as nocardiosis, atypical mycobacteriosis, leishmaniasis, among others, can also express this clinical pattern. Sporotrichosis, which often occurs in gardeners, remains the most recognized cause of nodular lymphangitis. The histopathological studies, as well as the culture are diagnostic standards of lesions that do not respond to empirical treatment. In this article, we will review the main causes of nodular lymphangitis or lymphocutaneous sporotrichoid infections.

Airborne bioaerosols and their impact on human health

Bioaerosols consist of aerosols originated biologically such as metabolites, toxins, or fragments of microorganisms that are present ubiquitously in the environment. International interests in bioaerosols have increased rapidly to broaden the pool of knowledge on their identification, quantification, distribution, and health impacts (e.g., infectious and respiratory diseases, allergies, and cancer). However, risk assessment of bioaerosols based on conventional culture methods has been hampered further by several factors such as: (1) the complexity of microorganisms or derivatives to be investigated; (2) the purpose, techniques, and locations of sampling; and (3) the lack of valid quantitative criteria (e.g., exposure standards and dose/effect relationships). Although exposure to some microbes is considered to be beneficial for health, more research is needed to properly assess their potential health hazards including inter-individual susceptibility, interactions with non-biological agents, and many proven/unproven health effects (e.g., atopy and atopic diseases).

Shock and lethality with anthrax edema toxin in rats are associated with reduced arterial responsiveness to phenylephrine and are reversed with adefovir

Although edema toxin (ETx) and lethal toxin (LTx) contribute to Bacillus anthracis shock and lethality, the mechanisms underlying their cardiovascular effects are unclear. We have previously shown that ETx but not LTx inhibited phenylephrine-stimulated contraction of aortic rings prepared from healthy rats and that adefovir, a selective inhibitor of ETx cAMP production, blocked this effect. Here, we examined arterial function in rats that received 24-h ETx or LTx infusions. Compared with control rats, ETx reduced mean arterial pressure (MAP) and survival over 48 h (P ≤ 0.0003) and increased plasma cAMP at 4, 24, and 48 h (P < 0.0001) and nitric oxide (NO) at 24 and 48 h (P ≤ 0.01). Compared with control animals, at 24- and 48-h phenylephrine stimulation of aortic rings from ETx animals produced decreased maximal contractile force (MCF; P = 0.05 and 0.006) and in vivo phenylephrine infusion in ETx animals produced decreased proportional increases in MAP (P < 0.0001 and P = 0.05). In ETx-treated animals, compared with placebo-treated animals, adefovir treatment prevented all lethality (P = 0.01), increased MAP (P ≤ 0.0001), decreased plasma and aortic tissue cAMP at 24 and 48 h, respectively (P ≤ 0.03), and plasma NO at both times (P ≤ 0.004), and increased phenylephrine-stimulated increases in MCF in aortic rings and MAP in vivo at 48 h (P = 0.02). LTx decreased MAP and survival also, but it did not alter the response to phenylephrine of MCF in aortic rings prepared from LTx animals or of MAP in vivo. In conclusion, in rats, hypotension and lethality are associated with reduced arterial contractile function with ETx but not LTx and adefovir improves ETx-induced hypotension and lethality.NEW & NOTEWORTHY The most important aspects of the present study are the findings that 1) in vivo challenge with anthrax edema but not lethal toxin depresses arterial contractile function measured both ex vivo and in vivo and 2) adefovir inhibits the effects of edema toxin on arterial hypotension and improves survival with lethal dose of edema toxin challenge.

Development of antibacterial conjugates using sulfamethoxazole with monocyclic terpenes: A systematic medicinal chemistry based computational approach

BACKGROUND AND OBJECTIVE

To develop 6 conjugate agents of the moribund antibiotic sulfamethoxazole (SMZ) joined to 6 individual monoterpenes, followed by protocols of medicinal chemistry as potent antibacterials, against multidrug resistant (MDR) human gruesome pathogenic bacteria.

METHODS

Antibacterial activities of the proposed conjugates were ascertained by the 'prediction of activity spectra of substances' (PASS) program. Drug-likeness parameters and toxicity profiles of conjugates were standardized with the Lipinski rule of five, using cheminformatic tools, Molsoft, molinspiration, OSIRIS and ProTox. Antibacterial activities of individual chemicals and conjugates were examined by targeting the bacterial folic acid biosynthesis enzyme, dihydropteroate synthases (DHPSs) of bacteria, Bacillus anthracis, Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae and Mycobacterium tuberculosis, with 3D structures of DHPSs from protein data bank.

RESULTS

According to the PASS program, biological spectral values of conjugate-2, conjugate-5 and conjugate-6 were ascertained effective with 'probably active' or 'Pa' value > 0.5, for anti-infective and antituberculosic activities. Using molecular docking against 5 cited bacterial DHPSs, effective docking scores of 6 monoterpenes in the specified decreasing order (kcal/mol): -9.72 (eugenol against B. anthracis), -9.61 (eugenol against S. pneumoniae), -9. 42 (safrol, against B. anthracis), -9.39 (thymol, against M. tuberculosis), -9.34 (myristicin, against S. pneumoniae) and -9.29 (thymol, against B. anthracis); whereas the lowest docking score of SMZ was -8.46kcal/mol against S. aureus DHPS. Similarly, effective docking scores of conjugates were as specified (kcal/mol.): -10.80 (conjugate-4 consisting SMZ+safrol, against M. tuberculosis), -10.78 (conjugate-5 consisting SMZ+thymol, against M. tuberculosis), -10.60 (conjugate-5 against B. anthracis), -10.26 (conjugate-2 consisting SMZ+ eugenol, against M. tuberculosis), -10.25 (conjugate-5, against S. aureus) and -10.19 (conjugate-2 against S. pneumoniae. Conjugates-2 and -5 were the most effective antibacterials based on Lipinski rule of five with lethal doses 3471 and 3500mg/kg, respectively and toxicity class levels.

CONCLUSIONS

Conjugate-2 and conjugate-5 were more effective than individual monoterpenes and SMZ, against pathogenic bacteria. Synthesis, characterization and in vitro antibacterial study with acute toxicity testing for Wister rat model of the conjugate-5 could land at success in the recorded computational trial and it could be promoted for synthesis in the control of MDR bacteria.

Microbial Diversity of Source and Point-of-Use Water in Rural Haiti - A Pyrosequencing-Based Metagenomic Survey

Haiti endures the poorest water and sanitation infrastructure in the Western Hemisphere, where waterborne diseases cause significant morbidity and mortality. Most of these diseases are reported to be caused by waterborne pathogens. In this study, we examined the overall bacterial diversity of selected source and point-of-use water from rural areas in Central Plateau, Haiti using pyrosequencing of 16s rRNA genes. Taxonomic composition of water samples revealed an abundance of Firmicutes phyla, followed by Proteobacteria and Bacteroidetes. A total of 38 bacterial families and 60 genera were identified. The presence of several Klebsiella spp. (tentatively, K. pneumoniae, K. variicola and other Klebsiella spp.) was detected in most water samples. Several other human pathogens such as Aeromonas, Bacillus, Clostridium, and Yersinia constituted significantly higher proportion of bacterial communities in the point-of-use water samples compared to source water. Bacterial genera traditionally associated with biofilm formation, such as Chryseobacterium, Fusobacterium, Prevotella, Pseudomonas were found in the point-of-use waters obtained from water filters or domestic water storage containers. Although the pyrosequencing method utilized in this study did not reveal the viability status of these pathogens, the abundance of genetic footprints of the pathogens in water samples indicate the probable risk of bacterial transmission to humans. Therefore, the importance of appropriate handling, purification, and treatment of the source water needed to be clearly communicated to the communities in rural Haiti to ensure the water is safe for their daily use and intake.

Ca-asp bound X-ray structure and inhibition of Bacillus anthracis dihydroorotase (DHOase)

Dihydroorotase (DHOase) is the third enzyme in the de novo pyrimidine synthesis pathway and is responsible for the reversible cyclization of carbamyl-aspartate (Ca-asp) to dihydroorotate (DHO). DHOase is further divided into two classes based on several structural characteristics, one of which is the length of the flexible catalytic loop that interacts with the substrate, Ca-asp, regulating the enzyme activity. Here, we present the crystal structure of Class I Bacillus anthracis DHOase with Ca-asp in the active site, which shows the peptide backbone of glycine in the shorter loop forming the necessary hydrogen bonds with the substrate, in place of the two threonines found in Class II DHOases. Despite the differences in the catalytic loop, the structure confirms that the key interactions between the substrate and active site residues are similar between Class I and Class II DHOase enzymes, which we further validated by mutagenesis studies. B. anthracis DHOase is also a potential antibacterial drug target. In order to identify prospective inhibitors, we performed high-throughput screening against several libraries using a colorimetric enzymatic assay and an orthogonal fluorescence thermal binding assay. Surface plasmon resonance was used for determining binding affinity (KD) and competition analysis with Ca-asp. Our results highlight that the primary difference between Class I and Class II DHOase is the catalytic loop. We also identify several compounds that can potentially be further optimized as potential B. anthracis inhibitors.

Mapping the Distribution of Anthrax in Mainland China, 2005-2013

Background

Anthrax, a global re-emerging zoonotic disease in recent years is enzootic in mainland China. Despite its significance to the public health, spatiotemporal distributions of the disease in human and livestock and its potential driving factors remain poorly understood.

Methodology/Principal Findings

Using the national surveillance data of human and livestock anthrax from 2005 to 2013, we conducted a retrospective epidemiological study and risk assessment of anthrax in mainland China. The potential determinants for the temporal and spatial distributions of human anthrax were also explored. We found that the majority of human anthrax cases were located in six provinces in western and northeastern China, and five clustering areas with higher incidences were identified. The disease mostly peaked in July or August, and males aged 30–49 years had higher incidence than other subgroups. Monthly incidence of human anthrax was positively correlated with monthly average temperature, relative humidity and monthly accumulative rainfall with lags of 0–2 months. A boosted regression trees (BRT) model at the county level reveals that densities of cattle, sheep and human, coverage of meadow, coverage of typical grassland, elevation, coverage of topsoil with pH > 6.1, concentration of organic carbon in topsoil, and the meteorological factors have contributed substantially to the spatial distribution of the disease. The model-predicted probability of occurrence of human cases in mainland China was mapped at the county level.

Conclusions/Significance

Anthrax in China was characterized by significant seasonality and spatial clustering. The spatial distribution of human anthrax was largely driven by livestock husbandry, human density, land cover, elevation, topsoil features and climate. Enhanced surveillance and intervention for livestock and human anthrax in the high-risk regions, particularly on the Qinghai-Tibetan Plateau, is the key to the prevention of human infections.

Anthrax is a worldwide zoonosis affecting mostly grazing herbivores, with occasional spillover to humans who have contact with infected animals or contaminated animal products. We characterized the distributional patterns of both human and livestock anthrax in China from 2005 to 2013, and identified agro-ecological, environmental and meteorological factors contributing to the temporal and spatial distributions of the disease. We found that the spatial distribution of human anthrax in China was mainly driven by densities of cattle, sheep and humans, coverage of meadow, coverage of typical grassland, elevation, pH level of topsoil, concentration of organic carbon in topsoil, and meteorological factors. We also identified the regions with higher probabilities for the occurrence of human cases. Our findings provided a clear qualitative and quantitative understanding of the epidemiological characteristics and risk recognition of anthrax in China, and can be helpful for prioritizing surveillance and control programs in the future.

Identifying Meningitis During an Anthrax Mass Casualty Incident: Systematic Review of Systemic Anthrax Since 1880

BACKGROUND

Bacillus anthracis, the causative agent of anthrax, is a potential bioterrorism agent. Anthrax meningitis is a common manifestation of B. anthracis infection, has high mortality, and requires more aggressive treatment than anthrax without meningitis. Its rapid identification and treatment are essential for successful management of an anthrax mass casualty incident.

METHODS

Three hundred six published reports from 1880 through 2013 met predefined inclusion criteria. We calculated descriptive statistics for abstracted cases and conducted multivariable regression on separate derivation and validation cohorts to identify clinical diagnostic and prognostic factors for anthrax meningitis.

RESULTS

One hundred thirty-two of 363 (36%) cases with systemic anthrax met anthrax meningitis criteria. Severe headache, altered mental status, meningeal signs, and other neurological signs at presentation independently predicted meningitis in the derivation cohort and were tested as a 4-item assessment tool for use during anthrax mass casualty incidents. Presence of any 1 factor on admission had a sensitivity for finding anthrax meningitis of 89% (83%) in the adult (pediatric) validation cohorts. Anthrax meningitis was unlikely in the absence of any of these signs or symptoms (likelihood ratio [LR]- = 0.12 [0.19] for adult [pediatric] cohorts), while presence of 2 or more made meningitis very likely (LR+ = 26.5 [30.0]). Survival of anthrax meningitis was predicted by treatment with a bactericidal agent (P = .005) and use of multiple antimicrobials (P = .01).

CONCLUSIONS

We developed an evidence-based assessment tool for screening patients for meningitis during an anthrax mass casualty incident. Its use could improve both patient outcomes and resource allocation in such an event.

A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines

Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens.

CD4+ T Cells Targeting Dominant and Cryptic Epitopes from Bacillus anthracis Lethal Factor

Anthrax is an endemic infection in many countries, particularly in the developing world. The causative agent, Bacillus anthracis, mediates disease through the secretion of binary exotoxins. Until recently, research into adaptive immunity targeting this bacterial pathogen has largely focused on the humoral response to these toxins. There is, however, growing recognition that cellular immune responses involving IFNγ producing CD4+ T cells also contribute significantly to a protective memory response. An established concept in adaptive immunity to infection is that during infection of host cells, new microbial epitopes may be revealed, leading to immune recognition of so called ‘cryptic’ or ‘subdominant’ epitopes. We analyzed the response to both cryptic and immunodominant T cell epitopes derived from the toxin component lethal factor and presented by a range of HLA-DR alleles. Using IFNγ-ELISpot assays we characterized epitopes that elicited a response following immunization with synthetic peptide and the whole protein and tested their capacities to bind purified HLA-DR molecules in vitro. We found that DR1 transgenics demonstrated T cell responses to a greater number of domain III cryptic epitopes than other HLA-DR transgenics, and that this pattern was repeated with the immunodominant epitopes, as a greater proportion of these epitopes induced a T cell response when presented within the context of the whole protein. Immunodominant epitopes LF_457-476 and LF_467-487 were found to induce a T cell response to the peptide, as well as to the whole native LF protein in DR1 and DR15, but not in DR4 transgenics. The analysis of Domain I revealed the presence of several unique cryptic epitopes all of which showed a strong to moderate relative binding affinity to HLA-DR4 molecules. However, none of the cryptic epitopes from either domain III or I displayed notably high binding affinities across all HLA-DR alleles assayed. These responses were influenced by the specific HLA alleles presenting the peptide, and imply that construction of future epitope string vaccines which are immunogenic across a wide range of HLA alleles could benefit from a combination of both cryptic and immunodominant anthrax epitopes.

Does Bacillus anthracis Lethal Toxin Directly Depress Myocardial Function? A Review of Clinical Cases and Preclinical Studies

The US outbreak of B.anthracis infection in 2001 and subsequent cases in the US and Europe demonstrate that anthrax is a continuing risk for the developed world. While several bacterial components contribute to the pathogenesis of B. anthracis, production of lethal toxin (LT) is strongly associated with the development of hypotension and lethality. However, the mechanisms underlying the cardiovascular instability LT produces are unclear. Some evidence suggests that LT causes shock by impairing the peripheral vasculature, effects consistent with the substantial extravasation of fluid in patients dying with B. anthracis. Other data suggests that LT directly depresses myocardial function. However a clinical correlate for this latter possibility is less evident since functional studies and post-mortem examination in patients demonstrate absent or minimal cardiac changes. The purposes of this review were to first present clinical studies of cardiac functional and histologic pathology with B. anthracis infection and to then examine in vivo, in vitro, and ex vivo preclinical studies of LT’s myocardial effects. Together, these data suggest that it is unclear whether that LT directly depresses cardiac function. This question is important for the clinical management and development of new therapies for anthrax and efforts should continue to be made to answer it.

Historical evolution of human anthrax from occupational disease to potentially global threat as bioweapon

PURPOSE

Anthrax is caused by Bacillus anthracis, which can naturally infect livestock, wildlife and occupationally exposed humans. However, for its resistance due to spore formation, ease of dissemination, persistence in the environment and high virulence, B. anthracis has been considered the most serious bioterrorism agent for a long time. During the last century anthrax evolved from limited natural disease to potentially global threat if used as bioweapon. Several factors may mitigate the consequences of an anthrax attack, including 1. the capability to promptly recognize and manage the illness and its public health consequences; 2. the limitation of secondary contamination risk through an appropriate decontamination; and 3. the evolution of genotyping methods (for microbes characterization at high resolution level) that can influence the course and/or focus of investigations, impacting the response of the government to an attack.

METHODS

A PubMed search has been done using the key words “bioterrorism anthrax”.

RESULTS

Over one thousand papers have been screened and the most significant examined to present a comprehensive literature review in order to discuss the current knowledge and strategies in preparedness for a possible deliberate release of B. anthracis spores and to indicate the most current and complete documents in which to deepen.

CONCLUSIONS

The comprehensive analysis of the two most relevant unnatural anthrax release events, Sverdlovsk in the former Soviet Union (1979) and the contaminated letters in the USA (2001), shows that inhalational anthrax may easily and cheaply be spread resulting in serious consequences. The damage caused by an anthrax attack can be limited if public health organization, first responders, researchers and investigators will be able to promptly manage anthrax cases and use new technologies for decontamination methods and in forensic microbiology.

An Aggregate of Four Anthrax Cases during the Dry Summer of 2011 in Epirus, Greece

BACKGROUND

Human anthrax is currently a sporadic disease in Europe, without significant regional clustering.

OBJECTIVE

To report an unexpected aggregate of anthrax cases and correlate local climatic factors with yearly anthrax admissions.

METHODS

Clinical description of a geographical-temporal anthrax aggregate, correlation of disease admissions with local weather data in the period 2001-2014 and literature reports of anthrax clusters from Europe in the last 20 years.

RESULTS

We identified 5 cases, all cutaneous: an unexpected aggregate of 4 cases in mid-summer 2011 (including a probable human-to-human transmission) and a sporadic case in August 2005, all in relatively dry periods (p < 0.05). Remarkably, 3/6 reports of human anthrax aggregates from Europe were observed in Balkan Peninsula countries in the year 2011.

CONCLUSION

In the light of the predicted climatic change, unexpected anthrax aggregates during dry periods in southern Europe underscore the risk of future anthrax re-emergence on this continent.

Whole Genome Analysis of Injectional Anthrax Identifies Two Disease Clusters Spanning More Than 13 Years

Background

Anthrax is a rare disease in humans but elicits great public fear because of its past use as an agent of bioterrorism. Injectional anthrax has been occurring sporadically for more than ten years in heroin consumers across multiple European countries and this outbreak has been difficult to trace back to a source.

Methods

We took a molecular epidemiological approach in understanding this disease outbreak, including whole genome sequencing of Bacillus anthracis isolates from the anthrax victims. We also screened two large strain repositories for closely related strains to provide context to the outbreak.

Findings

Analyzing 60 Bacillus anthracis isolates associated with injectional anthrax cases and closely related reference strains, we identified 1071 Single Nucleotide Polymorphisms (SNPs). The synapomorphic SNPs (350) were used to reconstruct phylogenetic relationships, infer likely epidemiological sources and explore the dynamics of evolving pathogen populations. Injectional anthrax genomes separated into two tight clusters: one group was exclusively associated with the 2009–10 outbreak and located primarily in Scotland, whereas the second comprised more recent (2012–13) cases but also a single Norwegian case from 2000.

Interpretation

Genome-based differentiation of injectional anthrax isolates argues for at least two separate disease events spanning > 12 years. The genomic similarity of the two clusters makes it likely that they are caused by separate contamination events originating from the same geographic region and perhaps the same site of drug manufacturing or processing. Pathogen diversity within single patients challenges assumptions concerning population dynamics of infecting B. anthracis and host defensive barriers for injectional anthrax.

Funding

This work was supported by the United States Department of Homeland Security grant no. HSHQDC-10-C-00,139 and via a binational cooperative agreement between the United States Government and the Government of Germany. This work was supported by funds from the German Ministry of Defense (Sonderforschungsprojekt 25Z1-S-431,214). Support for sequencing was also obtained from Illumina, Inc. These sources had no role in the data generation or interpretation, and had not role in the manuscript preparation.

Panel 1: Research in Context Systematic Review

We searched PubMed for any article published before Jun. 17, 2015, with the terms “Bacillus anthracis” and “heroin”, or “injectional anthrax”. Other than our previously published work (Price et al., 2012), we found no other relevant studies on elucidating the global phylogenetic relationships of B. anthracis strains associated with injectional anthrax caused by recreational heroin consumption of spore-contaminated drug. There were, however, publically available genome sequences of two strains involved (Price et al., 2012, Grunow et al., 2013) and the draft genome sequence of Bacillus anthracis UR-1, isolated from a German heroin user (Ruckert et al., 2012) with only limited information on the genotyping of closely related strains (Price et al., 2012, Grunow et al., 2013).

Lay Person Interpretation

Injectional anthrax has been plaguing heroin drug users across Europe for more than 10 years. In order to better understand this outbreak, we assessed genomic relationships of all available injectional anthrax strains from four countries spanning a > 12 year period. Very few differences were identified using genome-based analysis, but these differentiated the isolates into two distinct clusters. This strongly supports a hypothesis of at least two separate anthrax spore contamination events perhaps during the drug production processes. Identification of two events would not have been possible from standard epidemiological analysis. These comprehensive data will be invaluable for classifying future injectional anthrax isolates and for future geographic attribution.

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Whole genome sequences of injectional anthrax B. anthracis isolates fall in two tight but distinct genomic clusters.

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The distinct genomic clusters are consistent with two or more disease events that overlap in time and space.

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Defining pathogen clusters will lead to better public health responses to difficult to track disease outbreaks.

Human Anthrax Transmission at the Urban-Rural Interface, Georgia

Human anthrax has increased dramatically in Georgia and was recently linked to the sale of meat in an urban market. We assessed epidemiological trends and risk factors for human anthrax at the urban–rural interface. We reviewed epidemiologic records (2000–2012) that included the place of residence (classified as urban, peri-urban, or rural), age, gender, and self-reported source of infection (handling or processing animal by-products and slaughtering or butchering livestock). To estimate risk, we used a negative binomial regression. The average incidence per 1 million population in peri-urban areas (24.5 cases) was > 2-fold higher compared with rural areas and > 3-fold higher compared with urban area. Risk from handling or purchasing meat was nearly 2-fold higher in urban areas and > 4-fold higher in peri-urban areas compared with rural area. Our findings suggest a high risk of anthrax in urban and peri-urban areas likely as a result of spillover from contaminated meat and animal by-products. Consumers should be warned to purchase meat only from licensed merchants.

Anthrax prophylaxis: recent advances and future directions

Anthrax is a serious, potentially fatal disease that can present in four distinct clinical patterns depending on the route of infection (cutaneous, gastrointestinal, pneumonic, or injectional); effective strategies for prophylaxis and therapy are therefore required. This review addresses the complex mechanisms of pathogenesis employed by the bacterium and describes how, as understanding of these has developed over many years, so too have current strategies for vaccination and therapy. It covers the clinical and veterinary use of live attenuated strains of anthrax and the subsequent identification of protein sub-units for incorporation into vaccines, as well as combinations of protein sub-units with spore or other components. It also addresses the application of these vaccines for conventional prophylactic use, as well as post-exposure use in conjunction with antibiotics. It describes the licensed acellular vaccines AVA and AVP and discusses the prospects for a next generation of recombinant sub-unit vaccines for anthrax, balancing the regulatory requirement and current drive for highly defined vaccines, against the risk of losing the “danger” signals required to induce protective immunity in the vaccinee. It considers novel approaches to reduce time to immunity by means of combining, for example, dendritic cell vaccination with conventional approaches and considers current opportunities for the immunotherapy of anthrax.

First Autochthonous Coinfected Anthrax in an Immunocompetent Patient

Cutaneous anthrax has a mortality rate of 20% if no antibacterial treatment is applied. The clinical manifestations of cutaneous anthrax are obviously striking, but coinfection may produce atypical lesions and mask the clinical manifestations and proper laboratory diagnosis. Anthrax is known to be more common in the Middle East and Iran is one of the countries in which the zoonotic form of anthrax may still be encountered. We report a case of a 19-years-old male who used to apply Venetian ceruse on his skin. Venetian ceruse (also known as Spirits of Saturn) is an old cosmetic product used for skin whitening traditionally made from sheep's spinal cord. The patient referred to the Referral Laboratory, Mazandaran University of Medical Sciences, Sari, Iran, with atypical dermatosis, pronounced pain, and oedema of the affected tissue. It was confirmed by both conventional and molecular analysis that culture was a mixture of Bacillus anthracis and Trichophyton interdigitale. The patient was initially treated with ceftriaxone (1000 mg/day for two weeks), gentamicin (1.5–2 mg/kg/day), terbinafine (200 mg/week for one month), and 1% clotrimazole cream (5 weeks) two times per day which resulted in gradual improvement. No relapse could be detected after one-year follow-up. Anthrax infection might present a broader spectrum of symptoms than expected by clinicians. These unfamiliar characteristics may lead to delayed diagnosis, inadequate treatment, and higher mortality rate. Clinicians need to be aware of this issue in order to have successful management over this infection.

Whole Genome-Sequencing and Phylogenetic Analysis of a Historical Collection of Bacillus anthracis Strains from Danish Cattle

Bacillus anthracis, the causative agent of anthrax, is known as one of the most genetically monomorphic species. Canonical single-nucleotide polymorphism (SNP) typing and whole-genome sequencing were used to investigate the molecular diversity of eleven B. anthracis strains isolated from cattle in Denmark between 1935 and 1988. Danish strains were assigned into five canSNP groups or lineages, i.e. A.Br.001/002 (n = 4), A.Br.Ames (n = 2), A.Br.008/011 (n = 2), A.Br.005/006 (n = 2) and A.Br.Aust94 (n = 1). The match with the A.Br.Ames lineage is of particular interest as the occurrence of such lineage in Europe is demonstrated for the first time, filling an historical gap within the phylogeography of the lineage. Comparative genome analyses of these strains with 41 isolates from other parts of the world revealed that the two Danish A.Br.008/011 strains were related to the heroin-associated strains responsible for outbreaks of injection anthrax in drug users in Europe. Eight novel diagnostic SNPs that specifically discriminate the different sub-groups of Danish strains were identified and developed into PCR-based genotyping assays.

Whole genome protein microarrays for serum profiling of immunodominant antigens of Bacillus anthracis

A commercial Bacillus anthracis (Anthrax) whole genome protein microarray has been used to identify immunogenic Anthrax proteins (IAP) using sera from groups of donors with (a) confirmed B. anthracis naturally acquired cutaneous infection, (b) confirmed B. anthracis intravenous drug use-acquired infection, (c) occupational exposure in a wool-sorters factory, (d) humans and rabbits vaccinated with the UK Anthrax protein vaccine and compared to naïve unexposed controls. Anti-IAP responses were observed for both IgG and IgA in the challenged groups; however the anti-IAP IgG response was more evident in the vaccinated group and the anti-IAP IgA response more evident in the B. anthracis-infected groups. Infected individuals appeared somewhat suppressed for their general IgG response, compared with other challenged groups. Immunogenic protein antigens were identified in all groups, some of which were shared between groups whilst others were specific for individual groups. The toxin proteins were immunodominant in all vaccinated, infected or other challenged groups. However, a number of other chromosomally-located and plasmid encoded open reading frame proteins were also recognized by infected or exposed groups in comparison to controls. Some of these antigens e.g., BA4182 are not recognized by vaccinated individuals, suggesting that there are proteins more specifically expressed by live Anthrax spores in vivo that are not currently found in the UK licensed Anthrax Vaccine (AVP). These may perhaps be preferentially expressed during infection and represent expression of alternative pathways in the B. anthracis “infectome.” These may make highly attractive candidates for diagnostic and vaccine biomarker development as they may be more specifically associated with the infectious phase of the pathogen. A number of B. anthracis small hypothetical protein targets have been synthesized, tested in mouse immunogenicity studies and validated in parallel using human sera from the same study.

Emerging and Underrecognized Complications of Illicit Drug Use

Illicit drug use can result in a wide range of medical complications. As the availability, synthesis, and popularity of illicit drugs evolve over time, new syndromes associated with their use may mimic infections. Some of these symptoms are anticipated drug effects, and others are complications of adulterants mixed with drugs or complications from the method of using drugs. Some illicit drugs are associated with rare infections, which are difficult to diagnosis with standard microbiological techniques. The goal of this review is to orient a wide range of clinicians-including general practitioners, emergency medicine providers, and infectious diseases specialists-to complications of illicit drug use that may be underrecognized. Improving awareness of infectious and noninfectious complications of illicit drug can expedite diagnosis and medical treatment of persons who use drugs and facilitate targeted harm reduction counseling to prevent future complications.

Molecular characterization of the circulating Bacillus anthracis in Jordan

To understand the biomolecular charcteristics of Bacillus anthracis in Jordan, 20 blood smear slides from dead animals with suspected anthrax were analyzed using conventional and molecular approaches. All slides were positive for B. anthracis by conventional staining but no growth of the organism on selective media was detected. However, of the 20 samples, 16 were B. anthracis DNA-positive using polymerase chain reaction (PCR). Seven samples provided enough quantity and quality of DNA, and their multilocus variable tandem repeat analysis (MLVA)-15 loci analysis revealed two different genotypes. All genotypes were belonging to A.B..r. 008/009 which is very common in Asia and Europe. Single nucleotide repeat (SNR) analysis revealed that there were no sub genotypes. Molecular diagnosis of animal anthrax in Jordan is not used routinely; henceforth, official diagnosis of anthrax is based on the observation of the slides by optical microscope and this can often cause reading errors. Therefore, the prevalence of the disease in Jordan might be slightly lower than that reported by the official bodies.

An overview of investigational toxin-directed therapies for the adjunctive management of Bacillus anthracis infection and sepsis

INTRODUCTION

Sepsis with Bacillus anthracis infection has a very high mortality rate despite appropriate antibiotic and supportive therapies. Over the past 15 years, recent outbreaks in the US and in Europe, coupled with anthrax's bioterrorism weapon potential, have stimulated efforts to develop adjunctive therapies to improve clinical outcomes. Since lethal toxin and edema toxin (LT and ET) make central contributions to the pathogenesis of B. anthracis, these have been major targets in this effort.

AREAS COVERED

Here, the authors review different investigative biopharmaceuticals that have been recently identified for their therapeutic potential as inhibitors of LT or ET. Among these inhibitors are two antibody preparations that have been included in the Strategic National Stockpile (SNS) and several more that have reached Phase I testing. Presently, however, many of these candidate agents have only been studied in vitro and very few tested in bacteria-challenged models.

EXPERT OPINION

Although a large number of drugs have been identified as potential therapeutic inhibitors of LT and ET, in most cases their testing has been limited. The use of the two SNS antibody therapies during a large-scale exposure to B. anthracis will be difficult. Further testing and development of agents with oral bioavailability and relatively long shelf lives should be a focus for future research.