Review of brucellosis cases from laboratory exposures in the United States in 2008 to 2011 and improved strategies for disease prevention

Efficacy of antibiotic prophylaxis to preventing brucellosis in accidental exposure: A systematic review

BACKGROUND

Antibiotic prophylaxis to prevent brucellosis after accidental exposure to Brucella is an important topic in public health. This study aimed to systematically review the efficacy of antibiotic prophylaxis following accidental exposure to Brucella in preventing human brucellosis disease.

METHODS

The study protocol was registered in PROSPERO (CRD42023456812). The outcomes included the incidence of brucellosis disease, adverse events rate, and antibiotic prophylaxis adherence. A comprehensive literature search, conducted until 20 November, 2023, involved Medline, Embase, Cochrane Library, and LILACS databases. Descriptive analysis and meta-analysis using R software were performed, risk of bias was assessed using JBI Critical appraisal tools, and certainty of evidence was assessed using the GRADE tool.

RESULTS

Among 3102 initially identified records, eight studies involving 97 individuals accidentally exposed, all focused on high-risk accidental exposure to Brucella in laboratory settings, were included in the review. All studies reported the prophylactic treatment comprising doxycycline at a dosage of 100 mg twice daily, combined with rifampicin at 600 mg, both administered over 21 days. Prophylaxis adherence was reported in 86% of cases, and incidence of brucellosis post-treatment was 0.01. Adverse events, mainly gastrointestinal, occurred in 26% of cases. Critical appraisal revealed limitations in reporting demographics and clinical information. The certainty of evidence was rated as 'very low,' emphasising the need for caution in interpreting the observed outcomes due to study design constraints and the absence of comparative groups.

CONCLUSIONS

PEP is an alternative practice reported in the literature, used in accidents with high-risk exposure to Brucella. The currently available evidence of the efficacy of antibiotic prophylaxis is insufficient to support a recommendation for or against the widespread use of antibiotic prophylaxis, so caution is needed in interpreting results due to the very low certainty of evidence, primarily stemming from case series and lack of comparative groups.

Development of a novel visual isothermal amplification assay for rapid detection of Brucella spp

Brucellosis is an economically important livestock disease worldwide besides having a noteworthy impact on human health. In this study, a rapid, simple, and ultra-sensitive nuclei-acid diagnostic technique was developed for the detection of brucellosis harnessing saltatory rolling circle amplification (SRCA). The diagnostic method was developed using World Organization for Animal Health (WOAH) approved primers targeting the bcsp31 gene of the Brucella genome. The assay can be accomplished within 90 min at a temperature of 65 °C without the requirement of sophisticated instrumentation. The result interpretation can be done with the naked eye with the aid of SYBR green dye. The developed technique displayed 100% specificity by amplifying only 10 reference and field strains of Brucella spp. and there was no cross-reactivity with the other tested pathogens. The lower limit of detections of SRCA and end-point PCR assays were 9.7 fg/μL (2.7 genome copies of Brucella) and 970 fg/μL, respectively. Thus, the developed SRCA assay was found to be 100× more sensitive than the end-point PCR assay. To the best of our knowledge, our study is the first one to develop an SRCA-based assay for the detection of brucellosis and it can be a diagnostic tool for resource-constrained laboratories and veterinary hospitals.

Review of major meat-borne zoonotic bacterial pathogens

The importance of meat-borne pathogens to global disease transmission and food safety is significant for public health. These pathogens, which can cause a variety of diseases, include bacteria, viruses, fungi, and parasites. The consumption of pathogen-contaminated meat or meat products causes a variety of diseases, including gastrointestinal ailments. Humans are susceptible to several diseases caused by zoonotic bacterial pathogens transmitted through meat consumption, most of which damage the digestive system. These illnesses are widespread worldwide, with the majority of the burden borne by developing countries. Various production, processing, transportation, and food preparation stages can expose meat and meat products to bacterial infections and/or toxins. Worldwide, bacterial meat-borne diseases are caused by strains of Escherichia coli, Salmonella, Listeria monocytogenes, Shigella, Campylobacter, Brucella, Mycobacterium bovis, and toxins produced by Staphylococcus aureus, Clostridium species, and Bacillus cereus. Additionally, consuming contaminated meat or meat products with drug-resistant bacteria is a severe public health hazard. Controlling zoonotic bacterial pathogens demands intervention at the interface between humans, animals, and their environments. This review aimed to highlight the significance of meat-borne bacterial zoonotic pathogens while adhering to the One Health approach for creating efficient control measures.

Zika Virus Infection During Research Vaccine Development: Investigation of the Laboratory-Acquired Infection via Nanopore Whole-Genome Sequencing

Zika virus (ZIKV) emerged as a serious public health problem since the first major outbreak in 2007. Current ZIKV diagnostic methods can successfully identify known ZIKV but are impossible to track the origin of viruses and pathogens other than known ZIKV strains. We planned to determine the ability of Whole Genome Sequencing (WGS) in clinical epidemiology by evaluating whether it can successfully detect the origin of ZIKV in a suspected case of laboratory-acquired infection (LAI). ZIKV found in the patient sample was sequenced with nanopore sequencing technology, followed by the production of the phylogenetic tree, based on the alignment of 38 known ZIKV strains with the consensus sequence. The closest viral strain with the consensus sequence was the strain used in the laboratory, with a percent identity of 99.27%. We think WGS showed its time-effectiveness and ability to detect the difference between strains to the level of a single base. Additionally, to determine the global number of LAIs, a literature review of articles published in the last 10 years was performed, and 53 reports of 338 LAIs were found. The lack of a universal reporting system was worrisome, as in the majority of cases (81.1%), the exposure route was unknown.

State of the art: Lateral flow assays toward the point-of-care foodborne pathogenic bacteria detection in food samples

Diverse chemicals and some physical phenomena recently introduced in nanotechnology have enabled scientists to develop useful devices in the field of food sciences. Concerning such developments, detecting foodborne pathogenic bacteria is now an important issue. These kinds of bacteria species have demonstrated severe health effects after consuming foods and high mortality related to acute cases. The most leading path of intoxication and infection has been through food matrices. Hence, quick recognition of foodborne bacteria agents at low concentrations has been required in current diagnostics. Lateral flow assays (LFAs) are one of the urgent and prevalently applied quick recognition methods that have been settled for recognizing diverse types of analytes. Thus, the present review has stressed on latest developments in LFAs-based platforms to detect various foodborne pathogenic bacteria such as Salmonella, Listeria, Escherichia coli, Brucella, Shigella, Staphylococcus aureus, Clostridium botulinum, and Vibrio cholera. Proper prominence has been given on exactly how the labels, detection elements, or procedures have affected recent developments in the evaluation of diverse bacteria using LFAs. Additionally, the modifications in assays specificity and sensitivity consistent with applied food processing techniques have been discussed. Finally, a conclusion has been drawn for highlighting the main challenges confronted through this method and offered a view and insight of thoughts for its further development in the future.

Brucellosis

Brucellosis is a common Zoonosis affecting half a million people annually. The most common mode of infection is by consuming unpasteurized milk or milk products. The general manifestations are those of fever with generalized symptoms. The nervous system is affected in 4-7% of cases. The manifestations are protean and include meningo-encephalitis as well as peripheral nervous system involvement. The diagnosis relies on culture, which is cumbersome and can be falsely negative. Agglutination tests for the various species of the organism are the mainstay for diagnosis. Treatment is for 3-6 months with combination therapy including Doxycycline, Rifampicin and ceftriaxone. The main issue is prevention and better animal husbandry.

Molecular investigation of infection sources and transmission chains of brucellosis in Zhejiang, China

In the present study, a total of 7793 samples from 5 different types of hosts were collected and tested, with a seroprevalence of 2.4% (184/7793). Although the seroprevalence of human and animal brucellosis is relatively low, numbers of human brucellosis cases reported have increased continuously from 2004 to 2018. A total of 118 Brucella strains containing 4 biotypes were obtained, including Brucella melitensis bv.1 (n = 8) and bv.3 (n = 106), Brucella abortus bv.3 (n = 3) and bv.7 (n = 1). Twenty-one shared MLVA-16 genotypes, each composed of 2 to 19 strains obtained from different hosts, suggest the occurrence of a brucellosis outbreak epidemic with multiple source points and laboratory infection events. Moreover, 30 shared MLVA-16 genotypes were observed among 59.6% (68/114) B. melitensis isolates from Zhejiang and strains from other 21 different provinces, especially northern provinces, China. The analysis highlighted the imported nature of the strains from all over the northern provinces with a dominant part from the developed areas of animal husbandry. These data revealed a potential transmission pattern of brucellosis in this region, due to introduced infected sheep leading to a brucellosis outbreak epidemic, and eventually causing multiple laboratory infection events. It is urgent to strengthen the inspection and quarantine of the introduced animals.

Revisiting Brucellosis in Small Ruminants of Western Border Areas in Pakistan

Brucellosis, globally known bacterial zoonosis, is endemic to Pakistan. B. abortus in bovines, B. melitensis in small ruminants and B. canis in dogs mainly cause this disease. A total of 1821 sera (1196 from sheep and 625 from goats) from animal herds near the Pakistan–Afghanistan border were collected. In parallel testing of sera for anti-Brucella antibodies (B. abortus and B. melitensis) was carried out by RBPT and indirect ELISA. The presence of Brucella DNA in sera was tested by real-time PCR. The overall percentage of seropositive samples was 0.99 (18/1821) by both tests. All positive samples originated from Baluchistan territory which translated into 1.76% (18/1021). None of the positive sera had signals for Brucella DNA and none of sera from goats carried detectable antibodies. Both tests showed an almost perfect agreement with Kappa statistics. The flock size was found to be associated with the presence of anti-Brucella antibodies. The samples of Khyber Pakhtunkhwa (KPK) tested negative in both serological tests and hence were not processed for real-time PCR. The present study shows the presence of anti-Brucella antibodies in sheep in the Baluchistan region of Pakistan. Diagnostic services need to be improved and test and slaughter policies might be implemented for eradication of Brucella infection in these areas. Awareness about the infection is needed at the farmer’s level. Isolation and molecular biology of the isolates could help with understanding the prevailing etiology in a better way.

Brucella Laboratory Exposures in Brazil: Rare or Unnoticed?

Laboratory exposures to Brucella spp. are preventable. After an outbreak in Brazil, human brucellosis was made statutorily reportable as well as laboratory accidents. After the implementation of this law, three laboratorial accidents with Brucella abortus were reported in a Brazilian city, and 58 workers were exposed from January 2019 to April 2020. We describe the exposure level, prophylaxis, and serosurvey after 6 months, and we highlight the importance of disease report.

An outbreak of Brucellosis via air-born transmission in a kitchen wastes disposing company in Lianyungang, China

Brucellosis is a bacterial zoonotic disease caused by pathogenic Brucella spp. An outbreak caused by B. melitensis at Jinchi Biotechnological Company engaged in collecting and disposing of kitchen wastes from catering units in Lianyungang is reported here. An epidemiological investigation and serosurvey were conducted, and pathogen detection was performed. Three confirmed brucella cases, one probable case and two recessive infectors were found out; the attack rate was 33.3%, the screening positive rate by RBPT was 25.0%. The pathogen was B. melitensis identified from three patients: two for B. melitensis, biovars 1, and one for B. melitensis, biovars 2. The main symptoms included fever, sweating, headache, arthralgia, weakness and chill. The epidemiological investigation found that the transmission mode in this outbreak was air-born transmission through aerosols from the process of unloading the food residues and wastes into the feeding inlet. This outbreak of brucellosis was confirmed with patients' clinical symptoms, laboratory testing and epidemiological finds. The disinfection and personal protection were complemented by the kitchen wastes disposing company.

Brucella Exposure Risk Events in 10 Clinical Laboratories, New York City, USA, 2015 to 2017

From 2015 to 2017, 11 confirmed brucellosis cases were reported in New York City, leading to 10 Brucella exposure risk events (Brucella events) in 7 clinical laboratories (CLs). Most patients had traveled to countries where brucellosis is endemic and presented with histories and findings consistent with brucellosis. CLs were not notified that specimens might yield a hazardous organism, as the clinicians did not consider brucellosis until they were notified that bacteremia with Brucella was suspected. In 3 Brucella events, the CLs did not suspect that slow-growing, small Gram-negative bacteria might be harmful. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), which has a limited capacity to identify biological threat agents (BTAs), was used during 4 Brucella events, which accounted for 84% of exposures. In 3 of these incidents, initial staining of liquid media showed Gram-positive rods or cocci, including some cocci in chains, suggesting streptococci. Over 200 occupational exposures occurred when the unknown isolates were manipulated and/or tested on open benches, including by procedures that could generate infectious aerosols. During 3 Brucella events, the CLs examined and/or manipulated isolates in a biological safety cabinet (BSC); in each CL, the CL had previously isolated Brucella Centers for Disease Control and Prevention recommendations to prevent laboratory-acquired brucellosis (LAB) were followed; no seroconversions or LAB cases occurred. Laboratory assessments were conducted after the Brucella events to identify facility-specific risks and mitigations. With increasing MALDI-TOF MS use, CLs are well-advised to adhere strictly to safe work practices, such as handling and manipulating all slow-growing organisms in BSCs and not using MALDI-TOF MS for identification until BTAs have been ruled out.

An accidental laboratory exposure to Brucella melitensis: the prospective post-exposure management and a detailed investigation into the nature of the exposure

Our aim was to prospectively manage 22 Brucella-exposed individuals and identify the lapses in laboratory practices that lead to the exposure. The exposed individuals were risk-stratified, assessed for post-exposure prophylaxis (PEP), counselled to self-monitor symptoms and followed-up with three serology tests. Staff laboratory practices were recorded. Ten out of 13 high-risk individuals received PEP within 48 h of exposure. Compliance with PEP and serology monitoring was 90 and 96 %, respectively. No brucellosis cases were documented. A single handler manipulated the Brucella isolate on the open bench. Movement of the isolate was tracked in detail, highlighting various points of laboratory non-conformance. Early PEP intervention is effective in preventing acquired brucellosis. Our pragmatic post-exposure management achieved high PEP and serology compliance. We experience first-hand how regular staff engagement motivated PEP adherence and interval blood sampling attendance. The enforcement of practical strategies and safety practices was also implemented without compromising our laboratory processing times.

Case Investigations of Infectious Diseases Occurring in Workplaces, United States, 2006-2015

Workers in specific settings and activities are at increased risk for certain infectious diseases. When an infectious disease case occurs in a worker, investigators need to understand the mechanisms of disease propagation in the workplace. Few publications have explored these factors in the United States; a literature search yielded 66 investigations of infectious disease occurring in US workplaces during 2006–2015. Reported cases appear to be concentrated in specific industries and occupations, especially the healthcare industry, laboratory workers, animal workers, and public service workers. A hierarchy-of-controls approach can help determine how to implement effective preventive measures in workplaces. Consideration of occupational risk factors and control of occupational exposures will help prevent disease transmission in the workplace and protect workers’ health.

Lateral flow biosensor combined with loop-mediated isothermal amplification for simple, rapid, sensitive, and reliable detection of Brucella spp

Brucella species is responsible for brucellosis in human and animals, which is still of public health, veterinarian, and economic concern in many regions of the world. Here, a novel molecular diagnosis assay, termed loop-mediated isothermal amplification coupled with nanoparticles-based lateral flow biosensor (LAMP-LFB), was developed and validated for simply, rapidly, and reliably detecting all Brucella spp. strains. A set of six primers was designed based on the Brucella-specific gene Bscp31. The Brucella-LAMP results were visually reported by biosensor within 2 mins. A variety of bacterial strains representing several Brucella species, as well as several Gram-negative and Gram-positive bacterial species were used to determine the analytical sensitivity and specificity of the assay. Optimal LAMP conditions were 63°C for 40 mins, and the assay’s sensitivity was found to be 100 fg of genomic DNA in the pure cultures. No cross-reactions to non-Brucella strains were obtained; thus, analytical specificity of LAMP-LFB assay is of 100%. Using the protocol, 20 mins for rapid DNA preparation followed by isothermal amplification (40 mins) combined with biosensor detection (2 mins) resulted in a total assay time of approximately 65 mins. In the case of 117 whole blood samples, 13 (11.11%) samples were Brucella-positive by LAMP-LFB, and the diagnostic accuracy was 100% when compared to the culture-biotechnical method. In conclusion, Brucella-LAMP-LFB technique developed in this study is a sensitive and specific method to rapidly identify all Brucella spp. strains, and can be applied as a potential diagnostic tool for brucellosis in basic, clinical, and field laboratories.

Rapid Detection of Brucella spp. and Elimination of Carryover Using Multiple Cross Displacement Amplification Coupled With Nanoparticles-Based Lateral Flow Biosensor

Brucella spp.is capable of causing disease in a range of animal hosts, and human brucellosis is regarded as a life-threating disease. A novel isothermal amplification technique, termed multiple cross displacement amplification (MCDA), was employed for detecting all Brucella species strains. Brucella-MCDA targets the Bscp31 gene (Brucella species-specific gene) to specifically design a set of 10 primers. The Brucella-MCDA can be coupled with nanoparticles-based lateral flow biosensor (LFB) for highly specific, simple, rapid, and visual detection of Brucella-specific amplicons. Using the protocol, a MCDA amplification followed by 2 min LFB resulted in visualization of DNA products trapped at the LFB test line. Various species of Gram-positive and Gram-negative strains are applied for optimizing and evaluating the target assay. Optimal MCDA condition is found to be 63°C for 40 min, with detection limits at 10 fg of templates in the pure cultures. The specificity of MCDA-LFB technique is of 100%, and no cross-reactions to non-Brucella strains are observed according to the specificity examination. Furthermore, dUTP and AUDG enzyme are added into the MCDA reaction mixtures, which are used for removing false-positive amplification generating from carryover contamination. Thus, 20 min for rapid template extraction followed by AUDG digestion (5 min), MCDA (40 min) combined with LFB detection (2 min) resulted in a total assay time of ~70 min. In sum, Brucella-MCDA-LFB technique is a rapid, simple, reliable, and sensitive method to detect all Brucella species strains, and can be used as potential screening tool for Brucella strains in various laboratories.

Btp Proteins from Brucella abortus Modulate the Lung Innate Immune Response to Infection by the Respiratory Route

Although inhalation of infected aerosols is a frequent route for Brucella infection in humans, it rarely causes pulmonary clinical manifestations, suggesting a mild or nearly absent local inflammatory response. The goal of this study was to characterize the early innate immune response to intratracheal infection with Brucella abortus in mice and to evaluate whether it is modulated by this pathogen. After infection with 10⁶ CFU of B. abortus, the pulmonary bacterial burden at 7 days post-infection (p.i.) was comparable to the initial inoculum, despite an initial transient decline. Brucella was detected in spleen and liver as early as 1 day p.i. IL-1β and MCP-1 increased at 3 days p.i., whereas IL-12, KC, TNF-α, and IFN-γ only increased at 7 days p.i. Histological examination did not reveal peribronchial or perivascular infiltrates in infected mice. Experiments were conducted to evaluate if the limited inflammatory lung response to B. abortusis caused by a bacterial mechanism of TLR signaling inhibition. Whereas inoculation of E. coli LPS to control mice [phosphate-buffered saline (PBS)/LPS] caused lung inflammation, almost no histological changes were observed in mice preinfected intratracheally with B. abortus (WT/LPS). We speculated that the Brucella TIR-containing proteins (Btps) A and B, which impair TLR signaling in vitro, may be involved in this modulation. After LPS challenge, mice preinfected with the B. abortus btpAbtpB double mutant exhibited a stronger pulmonary polymorphonuclear infiltrate than WT/LPS mice, although milder than that of the PBS/LPS group. In addition, lungs from B. abortus btpAbtpB-infected mice presented a stronger inflammatory infiltrate than those infected with the WT strain, and at day 7 p.i., the pulmonary levels of KC, MCP-1, and IL-12 were higher in mice infected with the mutant. This study shows that B. abortus infection produces a mild proinflammatory response in murine lungs, partially due to immune modulation by its Btp proteins. This may facilitate its survival and dissemination to peripheral organs.

Incidence Patterns and Occupational Risk Factors of Human Brucellosis in Greece, 2004-2015

Background:

Brucellosis is the most common bacterial zoonosis worldwide. Greece has the highest reported incidence among EU countries. However, occupational risk factors have not been well described.

Objective:

To determine the incidence patterns and exposure risk factors of brucellosis in Greece.

Methods:

We used national-level surveillance and occupational denominator data to estimate the incidence patterns and exposure risk factors of brucellosis in Greece, with particular emphasis on occupation.

Results:

Between November 2003 and December 2015 a total of 2159 human brucellosis cases was reported. The mean incidence rate was 1.62 per 100 000 population per year. A large majority of cases (77.1%) reported consumption of unpasteurized milk or contact with livestock animals. Most cases occured in farmers and livestock breeders (1079 [87.7%] of 1231 cases reporting their occupation), corresponding to an annual incidence of 7.1 per 100 000. However, there were other occupations with a similar or higher risk: butchers and abattoir workers (12.7 per 100 000), laboratory personnel (3.1 per 100 000), while the highest risk was for veterinarians (53.2 per 100 000).

Conclusion:

Brucellosis incidence in specific occupational groups was much higher than in the general population. These results underline the importance of collecting information on occupation, both during the diagnostic process and in the surveillance system. Besides efforts to control brucellosis in animals, organized prevention efforts are needed within an occupational health framework, especially for the most vulnerable workers.

Detection of Brucella canis infection in dogs by blood culture and bacterial identification using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Brucella canis was recovered from dogs that were canine brucellosis suspect by blood culture using a modified lysis method. Organism identity was established by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The instrument-provided security library identified the isolates as Brucella species. The isolates were further identified as B. canis with the help of phenotypic and genotypic characteristics. The mass spectral profiles from characterized B. canis isolates, when added to the MALDI-TOF MS standard reference library, allowed successful presumptive identification of B. canis.

Epidemic characteristics, high-risk townships and space-time clusters of human brucellosis in Shanxi Province of China, 2005-2014

Background

Brucellosis, one of the world’s most important zoonosis, has been re-emerging in China. Shanxi Province, located in northern China, where husbandry development has been accelerated in recent years, has a rather high incidence of human brucellosis but drew little attention from the researchers. This study aimed to describe the changing epidemiology of human brucellosis in Shanxi Province from 2005 to 2014 and explore high-risk towns and space-time clusters for elucidating the necessity of decentralizing disease control resource to township level in epidemic regions, particularly in hotspot areas.

Methods

We extracted data from the Chinese National Notifiable Infectious Disease Reporting System to describe the incidence and spatiotemporal distribution of human brucellosis in Shanxi Province. Geographic information system was used to identify townships at high risk for the disease. Space-Time Scan Statistic was applied to detect the space-time clusters of human brucellosis during the past decade.

Results

From 2005 to 2014, a total of 50,002 cases of human brucellosis were recorded in Shanxi, with a male-to-female ratio of 3.9:1. The reported incidence rate increased dramatically from 7.0/100,000 in 2005 to 23.5/100,000 in 2014, with an average annual increase of 14.5%. There were still 33.8% cases delaying diagnosis in 2014. The proportion of the affected towns increased from 31.5% in 2005 to 82.5% in 2014. High-risk towns spread from the north to the center and then south of Shanxi Province, which were basins and adjacent highlands suitable for livestock cultivation. During the past decade, there were 55 space-time clusters of human brucellosis detected in high risk towns; the clusters could happen in any season. Some clusters’ location maintained stable over time.

Conclusions

During the last decade, Shanxi province’s human brucellosis epidemic had been aggravated and high-risk areas concentrated in some towns located in basins and adjacent highlands. Space-time clusters existed and some located steadily over time. Quite a few cases still missed timely diagnosis. Greater resources should be allocated and decentralized to mitigate the momentum of rise and improve the accessibility of prompt diagnosis treatment in the high-risk townships.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2086-x) contains supplementary material, which is available to authorized users.

Comparison of a New and Rapid Method: Brucella Coombs Gel Test With Other Diagnostic Tests

BACKGROUND

The aim of this study was to detect reliability of Brucella Coombs gel test (BCGT) by comparing with with ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination methods in serological diagnosis of brucellosis.

METHODS

Brucella Coombs gel test (BCGT), Brucella ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination tests of 78 patients with presumptive diagnosis of brucellosis which were sent to Microbiology Laboratory of Konya Numune Hospital from various regions of Konya were studied.

RESULTS

RESULTS

Of 78 patients with ELISA IgG and IgM, STA, BICA and BCGT; 26, 21, 10, 12 and 12 were positive. When compared with BICA, the sensitivity and specifity of BCGT were 100% and 100%, respectively.

CONCLUSION

According to results BCGT can be used as a diagnostic test in routine laboratories after more comprehensive studies in control groups and patients.

A Simple and Safe Protocol for Preparing Brucella Samples for Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry Analysis

We describe a simple protocol to inactivate the biosafety level 3 (BSL3) pathogens Brucella prior to their analysis by matrix-assisted laser desorption ionization-time of flight mass spectrometry. This method is also effective for several other bacterial pathogens and allows storage, and eventually shipping, of inactivated samples; therefore, it might be routinely applied to unidentified bacteria, for the safety of laboratory workers.

A Case-Study of Implementation of Improved Strategies for Prevention of Laboratory-acquired Brucellosis

Background

In 2012, the Alaska Section of Epidemiology investigated personnel potentially exposed to a Brucella suis isolate as it transited through three laboratories.

Methods

We summarize the first implementation of the United States Centers for Disease Control and Prevention 2013 revised recommendations for monitoring such exposures: (1) risk classification; (2) antimicrobial postexposure prophylaxis; (3) serologic monitoring; and (4) symptom surveillance.

Results

Over 30 people were assessed for exposure and subsequently monitored for development of illness. No cases of laboratory-associated brucellosis occurred. Changes were made to gaps in laboratory biosafety practices that had been identified in the investigation.

Conclusion

Achieving full compliance for the precise schedule of serologic monitoring was challenging and resource intensive for the laboratory performing testing. More refined exposure assessments could inform decision making for follow-up to maximize likelihood of detecting persons at risk while not overtaxing resources.

Hospital-associated transmission of Brucella melitensis outside the laboratory

Brucella melitensis was identified in an aspirate obtained from a patient's hip joint during a procedure at a hospital in Canada. We conducted an investigation into possible exposures among hospital workers; 1 worker who assisted with the procedure tested positive for B. melitensis. Aerosol-generating procedures performed outside the laboratory may facilitate transmission of this bacterium.

Human Brucella canis Infection and Subsequent Laboratory Exposures Associated with a Puppy, New York City, 2012

Human Brucella canis infection incidence is unknown. Most identified cases are associated with pet dogs. Laboratory-acquired infections can occur following contact with Brucella spp. We identified a paediatric B. canis case, the source and other exposed persons. A 3-year-old New York City child with fever and dyspnoea was hospitalized for 48 h for bronchiolitis. After her admission, blood culture grew B. canis, she was prescribed anti-microbials and recovered. B. canis was also isolated from blood of the child's pet dog; these isolates were genetically similar. The dog originated from an Iowa breeding facility which was quarantined after identification of the dog's infection. Additionally, 31 laboratory workers were exposed and subsequently monitored for symptoms; 15 completed post-exposure prophylaxis. To our knowledge, this is the first report strongly suggesting B. canis zoonotic transmission to a child in the United States, and highlights the need for coordinated control policies to minimize human illness.

A literature review of laboratory-acquired brucellosis

Brucellosis is a bacterial zoonotic disease which has been associated with laboratory-acquired infections. No recent reviews have addressed the characteristics of laboratory-acquired brucellosis (LAB). English-language literature was reviewed to identify reports of laboratory exposures to Brucella spp. and LAB cases between 1982 and 2007. Evaluation of 28 case reports identified 167 potentially exposed laboratory workers, of whom 71 had LAB. Nine reports were identified that summarized an additional 186 cases of LAB. Only 18 (11%) exposures were due to laboratory accidents, 147 (88%) exposures were due to aerosolization of organisms during routine identification activities, and the circumstances of 2 (1%) exposures were unknown. Brucella melitensis was the causative agent in 80% (135/167) of the exposures. Workers with high-risk exposures were 9.3 times more likely to develop LAB than workers with low-risk exposures (95% confidence interval [CI], 3.0 to 38.6; P < 0.0001); they were also 0.009 times likelier to develop LAB if they took antimicrobial PEP than if they did not (95% CI, 0 to 0.042; P < 0.0001). The median incubation period in case and summary reports was 8 weeks (range 1 to 40 weeks). Antimicrobial PEP is effective in preventing LAB. The incubation period may be used to identify appropriate serological and symptom surveillance time frames for exposed laboratory workers.