Anthrax ; diagnosis ; prevention & control ; therapy ; Bacillus anthracis ; growth & development ; Humans ; Microbiological Techniques

Anthrax is a zoonosis caused by Bacillus anthracis, which seriously affects human health. In recent years, a special phenomenon is found that the metabolic active of a bacterium remains after it is killed. To development of a KBMA (killed but metabolically active) Bacillus anthracis vaccine candidate strain, a plasmid pMAD and a recombinase system Cre-loxP were used to knockout the uvrAB gene of B. anthracis AP422 which lacks both of two plasmids pXO1 and pXO2. The results of PCR and RT-PCR shows that uvrAB genes were deleted from B. anthracis AP422 chromosome successfully. The constructed B. anthracis AP422deltauvrAB was inactivated by photochemical treatment (PCT) including an exposure in a long-wave-length ultraviolet (UVA) light and a treatment of 8-Methoxypsoralen (8-MOP), then the metabolic activity were detected by the method of MTS. The results showed that the killed B. anthracis AP422deltauvrAB maintained a highly metabolic activity for at least 4 hours, showing a state of KBMA. The KBMA strain of B. anthracis AP422deltauvrAB provides the prospective vaccine candidate strain for anthrax.
Anthrax ; immunology ; microbiology ; prevention & control ; Anthrax Vaccines ; genetics ; immunology ; radiation effects ; Bacillus anthracis ; genetics ; immunology ; Gene Knockout Techniques ; Methoxsalen ; pharmacology ; Ultraviolet Rays ; Vaccines, Inactivated ; genetics ; immunology

Adult ; Aged ; Animals ; Anthrax ; epidemiology ; prevention & control ; veterinary ; Cattle ; Disease Outbreaks ; prevention & control ; Disinfection ; Dogs ; Female ; Humans ; Male ; Middle Aged ; Prevalence

Objective: To analyze the epidemiological characteristics of anthrax in China from 2017 to 2019 and molecular typing of Bacillus anthracis isolated from some provinces (autonomous regions). Methods: Surveillance data of anthrax cases reported from 2017 to 2019 in the Infectious Disease Surveillance information System of China Disease Prevention and Control and the Public Health Emergency Reporting and Management Information System were collected, and descriptive epidemiological methods were used to analyze the epidemic characteristics, including the temporal, geographic and demographic distribution of this disease. A total of 47 strains of Bacillus anthracis isolated from 2017 to 2019 were analyzed by canSNP and MLVA15. Results: A total of 951 cases of anthrax were reported from 2017 to 2019, of which 938 were cutaneous anthrax, representing 98.63% of the total number reported. It was mainly distributed in the west and northeast of China, and the three provinces with the highest number of cases were Gansu (215), Sichuan (202) and Qinghai (191). Cases had been reported throughout the year, more cases occurred in the summer and autumn, and August was the month with the most cases,66.35% (211/318), 72.32% (243/336) and 68.01% (202/297) of cases were reported during June to September. The age distribution was mainly between 20 and 59 years old, accounting for more than 80% of all cases. The number of male cases was significantly higher than that of female cases, the ratio of male to female was about 3∶1. The occupations were mainly herdsmen and farmers, accounting for 49.70% to 58.18% and 31.45% to 36.70%, respectively. Public health events occurred every year, and 29 events had been reported from 2017 to 2019. canSNP analysis showed that 37 of the 47 strains belonged to the A.Br.001/002 subgroup and 10 belonged to the A.Br.Ames subgroup. MLVA15 analysis showed that there were 17 genotypes, of which 10 genotypes contained only one strain. Conclusion: Cutaneous anthrax was the predominant clinical type in China from 2017 to 2019.The seasonal, geographic and demographic distribution characteristics were evident.Molecular typing methods such as canSNP and MLVA15 can be used to trace the source of infectious diseases and provide technical support for anthrax prevention and control.
Adult ; Anthrax/prevention & control* ; Bacillus anthracis/genetics* ; China/epidemiology* ; Female ; Humans ; Male ; Middle Aged ; Molecular Typing ; Polymorphism, Single Nucleotide ; Skin Diseases, Bacterial ; Young Adult

Anthrax has become endemic throughout the upper Zambezi floodplain located in the Western Province of Zambia over the recent years. To date, no comprehensive study has been carried out to determine whether recurrence of anthrax outbreaks may be linked to differences in precipitation and human activities. Retrospective data for the period 1999 to 2007 showed that a total of 1,216 bovine cases of anthrax were reported. During the same period, 1,790 human anthrax cases and a corresponding case fatality rate of 4.63% (83/1,790) was documented in the upper Zambezi floodplain. Occurrence of human cases was highly correlated with cattle outbreaks (r = 0.94, p < 0.001). Differences in precipitation were significantly associated with the occurrence of anthrax outbreaks (chi2 = 4.75, p < 0.03), indicating that the likelihood of outbreaks occurring was higher during the dry months when human occupancy of the floodplain was greater compared to the flooding months when people and livestock moved out of this region. Human dependency on the floodplain was shown to significantly influence the epidemiology of anthrax in the upper Zambezi floodplain of western Zambia. Methods for mitigating anthrax outbreaks by disrupting the cycle of transmission are herein highlighted.
Animals ; Anthrax/*epidemiology/prevention & control/transmission/*veterinary ; Cattle ; Cattle Diseases/*epidemiology/prevention & control/transmission ; Climate ; Disease Outbreaks/*veterinary ; Human Activities ; Humans ; Retrospective Studies ; Seasons ; Zambia/epidemiology ; Zoonoses/epidemiology/microbiology/transmission

BACKGROUND: Anthrax is a zoonotic disease caused by Bacillus anthracis, a gram-positive, spore- forming bacillus. Several cases of anthrax have been reported in Korea; it occurred as an outbreak after ingesting raw meat of an anthrax-infected cow. Among those reported cases, most of them were of gastrointestinal anthrax and a case report of cutaneous anthrax was also included. An outbreak of anthrax occurred in a village of Chang-Nyeong, Kyoungsangnamdo, Korea on July, 2000. The source of infection was the meat of an infected cow. We investigated clinical features and epidemiologic characteristics of the outbreak. METHODS: Subjects were inhabitants and visitors who were exposed to the contaminated meat by ingestion or handling. Diagnosis and classification of clinical forms of anthrax were done according to the CDC case definition. A group of investigators composed of epidemiologists and medical doctors visited the village, and examined the residents and visitors exposed to contaminated meat by interviewing with standard questionare and physical examination. RESULTS: Among 40 persons who contacted meat by ingestion and/or handling, 5(12.5%) developed cutaneous anthrax and 2 of them died; 4 were confirmed cases and 1 was suspected case. B. anthracis was isolated from the vesicular lesions of hands or forearms in those 4 confirmed cases and, in one patient who died of meningitis, the organism was also isolated in blood culture. All patients were of cutaneous anthrax, 3 were recovered and 2 died due to complications : one of meningitis and the other of intracranial hemorrhage. All 40 people consumed meat in cooked state not in raw. No anthrax occurred in 28 persons who only ingested cooked meat without any contact with the raw meat. Five cases of cutaneous anthrax were developed among those 12 persons who handled raw meat in preparation for cooking. CONCLUSION: Anthrax should be suspected in patients with cutaneous lesions of vesicle or eschar on their exposed area after contacting animals or animal products, especially in an outbreak.
Animals ; Anthrax* ; Bacillus ; Bacillus anthracis ; Centers for Disease Control and Prevention (U.S.) ; Classification ; Cooking ; Diagnosis ; Eating ; Forearm ; Gyeongsangnam-do* ; Hand ; Humans ; Intracranial Hemorrhages ; Korea* ; Meat ; Meningitis ; Physical Examination ; Research Personnel ; Zoonoses

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.
Amoxicillin ; Animals ; Anthrax ; Anti-Infective Agents ; Bacillus anthracis ; Bacillus ; Cefotaxime ; Ceftriaxone ; Centers for Disease Control and Prevention (U.S.) ; Chloramphenicol ; Ciprofloxacin ; Clindamycin ; Communicable Diseases ; Disease Outbreaks ; Doxycycline ; Erythromycin ; Genotype ; Gentamicins ; Humans ; In Vitro Techniques ; Italy ; Linezolid ; Methods ; Microbial Sensitivity Tests ; Penicillin G ; Post-Exposure Prophylaxis ; Rifampin ; Spores ; Streptomycin ; Tandem Repeat Sequences ; Tetracycline ; Trimethoprim ; Vancomycin