Cutaneous anthrax in Lima, Peru: retrospective analysis of 71 cases, including four with a meningoencephalic complication

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.

Factors leading to dissemination of cutaneous anthrax: an international ID-IRI study

Background

Although anthrax is a rare zoonotic infection, it still causes significant mortality and morbidity. In this multicenter study, which is the largest anthrax case series ever reported, we aimed to describe the factors leading to dissemination of cutaneous anthrax.

Methods

Adult patients with cutaneous anthrax from 16 referral centers were pooled. The study had a retrospective design, and included patients treated between January 1, 1990 and December 1, 2019. Probable, and confirmed cases based upon CDC anthrax 2018 case definition were included in the study. A descriptive statistical analysis was performed for all variables.

Results

A total of 141 cutaneous anthrax patients were included. Of these, 105 (74%) patients had probable and 36 (26%) had confirmed diagnosis. Anthrax meningitis and bacteremia occurred in three and six patients, respectively. Sequelae were observed in three patients: cicatricial ectropion followed by ocular anthrax (n = 2) and movement restriction on the left hand after surgical intervention (n = 1). One patient had gastrointestinal anthrax. The parameters related to poor outcome (p < 0.05) were fever, anorexia, hypoxia, malaise/fatigue, cellulitis, fasciitis, lymphadenopathy, leukocytosis, high CRP and creatinine levels, longer duration of antimicrobial therapy, and combined therapy. The last two were seemingly the consequences of dissemination rather than being the reasons. The fatality rate was 1.4%.

Conclusions

Rapid identification of anthrax is crucial for prompt and effective treatment. Systemic symptoms, disseminated local infection, and high inflammatory markers should alert the treating physicians for the dissemination of the disease.

Anthrax outbreaks in Bangladesh, 2009-2010

During August 2009-October 2010, a multidisciplinary team investigated 14 outbreaks of animal and human anthrax in Bangladesh to identify the etiology, pathway of transmission, and social, behavioral, and cultural factors that led to these outbreaks. The team identified 140 animal cases of anthrax and 273 human cases of cutaneous anthrax. Ninety one percent of persons in whom cutaneous anthrax developed had history of butchering sick animals, handling raw meat, contact with animal skin, or were present at slaughtering sites. Each year, Bacillus anthracis of identical genotypes were isolated from animal and human cases. Inadequate livestock vaccination coverage, lack of awareness of the risk of anthrax transmission from animal to humans, social norms and poverty contributed to these outbreaks. Addressing these challenges and adopting a joint animal and human health approach could contribute to detecting and preventing such outbreaks in the future.

Clinical findings in children with cutaneous anthrax in eastern Turkey

Anthrax is a zoonosis produced by Bacillus anthracis. The aim of this study was to evaluate the clinical findings, therapy, and outcome in children with cutaneous anthrax (CA). Data on age, gender, occupation, clinical symptoms and findings, location and type of lesions, clinical history, laboratory findings, treatment, and outcome were recorded from patients' medical records, retrospectively. The study included 65 patients between 1 month and 18 years old (9.0±4.0 years), 37 patients (56.9%) were male and 28 (43.1%) were female. Most of the patients (89.1%) were admitted in summer and autumn (p<0.001). Of the 65 patients, 20 patients (30.8%) had received antibiotherapy before admission to our hospital. All patients except one had a contact history with infected animals. A 1-month-old patient had a contact history with his mother who had CA. On clinical examination, anthrax edema was noted in 36 (55.3%) patients, anthrax pustule in 27 (41.5%), and anthrax edema and anthrax pustule in two (3%) patients. Gram staining and culture was positive for B. anthracis in 35 (53.8%) patients, and only Gram staining was positive in 10 (15.4%) patients. In the remaining 20 (30.8%) patients, the diagnosis was made by clinical findings. Because the anthrax outbreak in Turkey was associated with slaughtering or milking of ill cows, sheep, or goats, and handling raw meat without taking any protective measures, persons in the community must be educated about using personal protective equipment during slaughtering of animals and handling of meat and skins.

Effects of anthrax lethal toxin on human primary keratinocytes

AIMS

To investigate the effects of anthrax lethal toxin (LeTx) on human primary keratinocytes.

METHODS AND RESULTS

We show here that human primary keratinocytes are resistant to LeTx-triggered cytotoxicity. All but one of the MEKs (mitogen-activated protein kinase kinases) are cleaved within 3 h, and the cleavage of MEKs in keratinocytes leads to their subsequent proteasome-mediated degradation at different rates. Moreover, LeTx reduced the concentration of several cytokines except RANTES in culture.

CONCLUSIONS

Our results indicate that primary keratinocytes are resistant to LeTx cytotoxicity, and MEK cleavage does not correlate with LeTx cytotoxicity. Although LeTx is considered as an anti-inflammatory agent, it upregulates RANTES.

SIGNIFICANCE AND IMPACT OF THE STUDY

According to a current view, the action of LeTx results in downregulation of the inflammatory response, as evidenced by diminished expression of several inflammatory biomarkers. Paradoxically, LeTx has been reported to attract neutrophils to cutaneous infection sites. This paper, which shows that RANTES, a chemoattractant for immune cells, is upregulated after exposure of keratinocytes to LeTx, although a number of other markers of the inflammatory response are downregulated. Our results might explain why the exposure of keratinocytes to LeTx results in the recruitment of neutrophils to cutaneous infection sites, while the expression of several inflammatory biomarkers is diminished.

Cutaneous anthrax in Eastern Turkey: a review of 85 cases

BACKGROUND

Anthrax is a zoonotic disease diminishing worldwide. Although a very rare disease in developed countries, anthrax is still endemic in developing countries.

AIM

To evaluate the clinical history and features, treatment and outcome of our patients with anthrax and emphasize the importance of the disease in our region.

METHOD

In this study, the records of all patients diagnosed with cutaneous anthrax admitted to Yüzüncü Yil University Medical Faculty between March 2002 and March 2007, were reviewed, and data on age, gender, occupation, clinical symptoms and findings, location and type of lesions, clinical history, laboratory findings, treatment and outcome were recorded.

RESULTS

There were 85 patients [46 (54.1%) male, 39 (45.9%) female; mean age 30.6 years, range 6-72]. All the patients had a history of contact with infected animals or animal products. The infectious agent was found using direct examination of Gram-stained smears from 17 patients (20%), and Bacillus anthracis was isolated from vesicle fluid cultures from 11 patients (12.9%). Diagnosis was based on clinical findings in the remaining 57 patients (67.1%). All patients, except for two with respiratory tract obstruction, made a full recovery.

CONCLUSION

Anthrax continues to be an endemic disease in Turkey, and should be considered in patients with a relevant contact history having a painless ulcer and vesicular skin lesions surrounded by a zone of oedema. Gram staining and simple culture methods are useful aids to diagnosis, but diagnosis may have to be based on clinical grounds in the majority of patients.