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Frontiers in Immunology 2021Current vaccination strategies against pertussis are sub-optimal. Optimal protection against , the causative agent of pertussis, likely requires mucosal immunity....
BACKGROUND
Current vaccination strategies against pertussis are sub-optimal. Optimal protection against , the causative agent of pertussis, likely requires mucosal immunity. Current pertussis vaccines consist of inactivated whole cells or purified antigens thereof, combined with diphtheria and tetanus toxoids. Although they are highly protective against severe pertussis disease, they fail to elicit mucosal immunity. Compared to natural infection, immune responses following immunization are short-lived and fail to prevent bacterial colonization of the upper respiratory tract. To overcome these shortcomings, efforts have been made for decades, and continue to be made, toward the development of mucosal vaccines against pertussis.
OBJECTIVES
In this review we systematically analyzed published literature on protection conferred by mucosal immunization against pertussis. Immune responses mounted by these vaccines are summarized.
METHOD
The PubMed Library database was searched for published studies on mucosal pertussis vaccines. Eligibility criteria included mucosal administration and the evaluation of at least one outcome related to efficacy, immunogenicity and safety.
RESULTS
While over 349 publications were identified by the search, only 63 studies met the eligibility criteria. All eligible studies are included here. Initial attempts of mucosal whole-cell vaccine administration in humans provided promising results, but were not followed up. More recently, diverse vaccination strategies have been tested, including non-replicating and replicating vaccine candidates given by three different mucosal routes: orally, nasally or rectally. Several adjuvants and particulate formulations were tested to enhance the efficacy of non-replicating vaccines administered mucosally. Most novel vaccine candidates were only tested in animal models, mainly mice. Only one novel mucosal vaccine candidate was tested in baboons and in human trials.
CONCLUSION
Three vaccination strategies drew our attention, as they provided protective and durable immunity in the respiratory tract, including the upper respiratory tract: acellular vaccines adjuvanted with lipopeptide LP1569 and c-di-GMP, outer membrane vesicles and the live attenuated BPZE1 vaccine. Among all experimental vaccines, BPZE1 is the only one that has advanced into clinical development.
Topics: Humans; Immunity, Mucosal; Pertussis Vaccine; Whooping Cough
PubMed: 34211481
DOI: 10.3389/fimmu.2021.701285 -
Pediatrics Sep 2019Live vaccines usually provide robust immunity but can transmit the vaccine virus.
CONTEXT
Live vaccines usually provide robust immunity but can transmit the vaccine virus.
OBJECTIVE
To assess the characteristics of secondary transmission of the vaccine-strain varicella-zoster virus (Oka strain; vOka) on the basis of the published experience with use of live varicella and zoster vaccines.
DATA SOURCES
Systematic review of Medline, Embase, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and Scopus databases for articles published through 2018.
STUDY SELECTION
Articles that reported original data on vOka transmission from persons who received vaccines containing the live attenuated varicella-zoster virus.
DATA EXTRACTION
We abstracted data to describe vOka transmission by index patient's immune status, type (varicella or herpes zoster) and severity of illness, and whether transmission was laboratory confirmed.
RESULTS
Twenty articles were included. We identified 13 patients with vOka varicella after transmission from 11 immunocompetent varicella vaccine recipients. In all instances, the vaccine recipient had a rash: 6 varicella-like and 5 herpes zoster. Transmission occurred mostly to household contacts. One additional case was not considered direct transmission from a vaccine recipient, but the mechanism was uncertain. Transmission from vaccinated immunocompromised children also occurred only if the vaccine recipient developed a rash postvaccination. Secondary cases of varicella caused by vOka were mild.
LIMITATIONS
It is likely that other vOka transmission cases remain unpublished.
CONCLUSIONS
Healthy, vaccinated persons have minimal risk for transmitting vOka to contacts and only if a rash is present. Our findings support the existing recommendations for routine varicella vaccination and the guidance that persons with vaccine-related rash avoid contact with susceptible persons at high risk for severe varicella complications.
Topics: Chickenpox Vaccine; Exanthema; Herpes Zoster Vaccine; Humans; Immunocompetence; Immunocompromised Host; Risk Factors; Seroconversion; Severity of Illness Index; Vaccines, Attenuated; Varicella Zoster Virus Infection
PubMed: 31471448
DOI: 10.1542/peds.2019-1305 -
The Cochrane Database of Systematic... Mar 2011This review is superseded by the published Cochrane Review, Saif‐Ur‐Rahman 2024 [https://doi.org/10.1002/14651858.CD014573], which considers only the oral killed... (Meta-Analysis)
Meta-Analysis Review
EDITORIAL NOTE
This review is superseded by the published Cochrane Review, Saif‐Ur‐Rahman 2024 [https://doi.org/10.1002/14651858.CD014573], which considers only the oral killed vaccines because the live oral vaccines do not have World Health Organization (WHO) prequalification. Saif‐Ur‐Rahman 2024 also considered only currently available WHO pre‐qualified oral killed cholera vaccines (Dukoral, Shanchol, and Euvichol/Euvichol‐Plus).
BACKGROUND
Cholera is a cause of acute watery diarrhoea which can cause dehydration and death if not adequately treated. It usually occurs in epidemics, and is associated with poverty and poor sanitation. Effective, cheap, and easy to administer vaccines could help prevent epidemics.
OBJECTIVES
To assess the effectiveness and safety of oral cholera vaccines in preventing cases of cholera and deaths from cholera.
SEARCH STRATEGY
In October 2010, we searched the Cochrane Infectious Disease Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; LILACS; the metaRegister of Controlled Trials (mRCT), and the WHO International Clinical Trials Registry Platform (ICTRP) for relevant published and ongoing trials.
SELECTION CRITERIA
Randomized or quasi-randomized controlled trials of oral cholera vaccines in healthy adults and children.
DATA COLLECTION AND ANALYSIS
Each trial was assessed for eligibility and risk of bias by two authors working independently. Data was extracted by two independent reviewers and analysed using the Review Manager 5 software. Outcomes are reported as vaccine protective efficacy (VE) with 95% confidence intervals (CIs).
MAIN RESULTS
Seven large efficacy trials, four small artificial challenge studies, and twenty-nine safety trials contributed data to this review.Five variations of a killed whole cell vaccine have been evaluated in large scale efficacy trials (four trials, 249935 participants). The overall vaccine efficacy during the first year was 52% (95% CI 35% to 65%), and during the second year was 62% (95% CI 51% to 62%). Protective efficacy was lower in children aged less than 5 years; 38% (95% CI 20% to 53%) compared to older children and adults; 66% (95% CI 57% to 73%).One trial of a killed whole cell vaccine amongst military recruits demonstrated 86% protective efficacy (95% CI 37% to 97%) in a small epidemic occurring within 4 weeks of the 2-dose schedule (one trial, 1426 participants). Efficacy data is not available beyond two years for the currently available vaccine formulations, but based on data from older trials is unlikely to last beyond three years.The safety data available on killed whole cell vaccines have not demonstrated any clinically significant increase in adverse events compared to placebo.Only one live attenuated vaccine has reached Phase III clinical evaluation and was not effective (one trial, 67508 participants). Two new candidate live attenuated vaccines have demonstrated clinical effectiveness in small artificial challenge studies, but are still in development.
AUTHORS' CONCLUSIONS
The currently available oral killed whole cell vaccines can prevent 50 to 60% of cholera episodes during the first two years after the primary vaccination schedule. The impact and cost-effectiveness of adopting oral cholera vaccines into the routine vaccination schedule of endemic countries will depend on the prevalence of cholera, the frequency of epidemics, and access to basic services providing rapid rehydration therapy.
Topics: Administration, Oral; Adult; Child; Cholera; Cholera Vaccines; Humans; Randomized Controlled Trials as Topic; Vaccines, Attenuated
PubMed: 21412922
DOI: 10.1002/14651858.CD008603.pub2 -
Human Vaccines & Immunotherapeutics 2014To assess the comparative effectiveness of a monovalent and a pentavalent rotavirus vaccine (RV1 and RV5), a Bayesian network meta-analysis was conducted. Data of... (Comparative Study)
Comparative Study Meta-Analysis Review
Bayesian network meta-analysis suggests a similar effectiveness between a monovalent and a pentavalent rotavirus vaccine: a preliminary report of re-analyses of data from a Cochrane Database Systematic Review.
To assess the comparative effectiveness of a monovalent and a pentavalent rotavirus vaccine (RV1 and RV5), a Bayesian network meta-analysis was conducted. Data of randomized trials from the Cochrane Review in 2012 were extracted and synthesized. For the prevention of severe rotavirus disease up to 2 years, no statistical difference was found in the effectiveness between the 2 types of vaccine (odds ratio: 2.23, 95% credible interval: 0.71-5.20). Similarly, the comparative effectiveness of RV1 and RV5 appeared equivalent for other rotavirus-associated outcome measures, such as prevention of severe disease up to 1 year and all severity of rotavirus infections for up to both 1- and 2-year follow-ups. These results indicates that, overall, RV1 and RV5 offer similar benefits to prevent rotavirus diseases; nonetheless, credible intervals are generally wide, highlighting the necessity of further meta-analyses including updated information or, ideally, controlled trials comparing both vaccines directly.
Topics: Bayes Theorem; Databases, Factual; Humans; Research Report; Rotavirus Infections; Rotavirus Vaccines; Treatment Outcome; Vaccines, Attenuated
PubMed: 24608099
DOI: 10.4161/hv.28284 -
Autoimmunity Reviews Jan 2022The treatment for COVID-19 often utilizes immune-modulating drugs. These drugs are also used in immune mediated inflammatory diseases (IMIDs). We performed a systematic... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The treatment for COVID-19 often utilizes immune-modulating drugs. These drugs are also used in immune mediated inflammatory diseases (IMIDs). We performed a systematic review about seroconversion after SARS-CoV-2 vaccination in patients with IMIDs and impact of various drugs on seroconversion rates.
METHODS
Electronic databases were searched to identify relevant studies reporting seroconversion rates following SARS-CoV-2 vaccination in IMIDs. We calculated the pooled seroconversion rates after a single or two doses of vaccination, pooled seroconversion rates in patients with specific IMIDs, and rates in patients on various drugs/drug classes.
RESULTS
Twenty-five studies were included in the systematic review. The pooled seroconversion rates after two doses of mRNA vaccination were higher (83.1, 95%CI: 74.9-89.0, I = 90%) as compared to a single dose (69.3, 52.4-82.3, I = 95%). The odds of seroconversion were lower in IMIDs as compared to healthy controls (0.05, 0.02-0.13, I = 21%). The seroconversion rates in patients with inflammatory bowel disease (95.2, 95%CI: 92.6-96.9, I = 0%), spondyloarthropathy (95.6, 95% CI: 83.4-98.9, I = 35%), and systemic lupus erythematosus (90.7, 95%CI: 85.4-94.2, I = 0%) were higher as compared to rheumatoid arthritis (79.5, 95% CI: 65.1-88.9, I = 85%), and vasculitis (70.5, 95% CI: 52.9-83.5, I = 51%). The seroconversion rates following double dose of mRNA were excellent (>90%) in those on anti-tumour necrosis factor (TNF), anti-integrin (vedolizumab), anti-IL 17 (secukinumab), anti-IL6 (Tocilizumab) and anti-IL12/23 (Ustekinumab) therapies but attenuated (<70%) in patients on anti-CD20 (Rituximab) or anti-cytotoxic T lymphocyte associated antigen (CTLA-4) therapies (Abatacept). The seroconversion rates were good (70-90%) with steroids, hydroxychloroquine, JAK inhibitors, mycophenolate mofetil and leflunomide. Combination of anti-TNF with immunomodulators (azathioprine, 6-meracptopurine, methotrexate) resulted in an attenuated vaccine response as compared to anti-TNF monotherapy.
CONCLUSION
Seroconversion rates after SARS-CoV-2 vaccination are lower in patients with IMIDs. Certain therapies (anti-TNF, anti-integrin, anti-IL 17, anti-IL6, anti-12/23) do not impact seroconversion rates while others (anti-CD20, anti-CTLA-4) result in poorer responses.
Topics: COVID-19; COVID-19 Vaccines; Humans; SARS-CoV-2; Tumor Necrosis Factor Inhibitors; Vaccination
PubMed: 34474172
DOI: 10.1016/j.autrev.2021.102927 -
Viruses Aug 2022Solid organ transplant (SOT) recipients are at greater risk of coronavirus disease 2019 (COVID-19) and have attenuated response to vaccinations. In the present... (Meta-Analysis)
Meta-Analysis
Solid organ transplant (SOT) recipients are at greater risk of coronavirus disease 2019 (COVID-19) and have attenuated response to vaccinations. In the present meta-analysis, we aimed to evaluate the serologic response to the COVID-19 vaccine in SOT recipients. A search of electronic databases was conducted to identify SOT studies that reported the serologic response to COVID-19 vaccination. We analyzed 44 observational studies including 6158 SOT recipients. Most studies were on mRNA vaccination (mRNA-1273 or BNT162b2). After a single and two doses of vaccine, serologic response rates were 8.6% (95% CI 6.8-11.0) and 34.2% (95% CI 30.1-38.7), respectively. Compared to controls, response rates were lower after a single and two doses of vaccine (OR 0.0049 [95% CI 0.0021-0.012] and 0.0057 [95% CI 0.0030-0.011], respectively). A third dose improved the rate to 65.6% (95% CI 60.4-70.2), but in a subset of patients who had not achieved a response after two doses, it remained low at 35.7% (95% CI 21.2-53.3). In summary, only a small proportion of SOT recipients achieved serologic response to the COVID-19 mRNA vaccine, and that even the third dose had an insufficient response. Alternative strategies for prophylaxis in SOT patients need to be developed. In this meta-analysis that included 6158 solid organ transplant recipients, the serologic response to the COVID-19 vaccine was extremely low after one (8.6%) and two doses (34.2%). The third dose of the vaccine improved the rate only to 66%, and in the subset of patients who had not achieved a response after two doses, it remained low at 36%. The results of our study suggest that a significant proportion of solid organ transplant recipients are unable to achieve a sufficient serologic response after completing not only the two series of vaccination but also the third booster dose. There is an urgent need to develop strategies for prophylaxis including modified vaccine schedules or the use of monoclonal antibodies in this vulnerable patient population.
Topics: Antibodies, Viral; BNT162 Vaccine; COVID-19; COVID-19 Testing; COVID-19 Vaccines; Humans; Organ Transplantation; Vaccination; Vaccines; Vaccines, Synthetic; mRNA Vaccines
PubMed: 36016444
DOI: 10.3390/v14081822 -
The Journal of Allergy and Clinical... Apr 2022Public health newborn screening (NBS) programs continuously evolve, taking advantage of international shared learning. NBS for severe combined immunodeficiency (SCID)...
BACKGROUND
Public health newborn screening (NBS) programs continuously evolve, taking advantage of international shared learning. NBS for severe combined immunodeficiency (SCID) has recently been introduced in many countries. However, comparison of screening outcomes has been hampered by use of disparate terminology and imprecise or variable case definitions for non-SCID conditions with T-cell lymphopenia.
OBJECTIVES
This study sought to determine whether standardized screening terminology could overcome a Babylonian confusion and whether improved case definitions would promote international exchange of knowledge.
METHODS
A systematic literature review highlighted the diverse terminology in SCID NBS programs internationally. While, as expected, individual screening strategies and tests were tailored to each program, we found uniform terminology to be lacking in definitions of disease targets, sensitivity, and specificity required for comparisons across programs.
RESULTS
The study's recommendations reflect current evidence from literature and existing guidelines coupled with opinion of experts in public health screening and immunology. Terminologies were aligned. The distinction between actionable and nonactionable T-cell lymphopenia among non-SCID cases was clarified, the former being infants with T-cell lymphopenia who could benefit from interventions such as protection from infections, antibiotic prophylaxis, and live-attenuated vaccine avoidance.
CONCLUSIONS
By bringing together the previously unconnected public health screening community and clinical immunology community, these SCID NBS deliberations bridged the gaps in language and perspective between these disciplines. This study proposes that international specialists in each disorder for which NBS is performed join forces to hone their definitions and recommend uniform registration of outcomes of NBS. Standardization of terminology will promote international exchange of knowledge and optimize each phase of NBS and follow-up care, advancing health outcomes for children worldwide.
Topics: Child; Data Collection; Humans; Infant; Infant, Newborn; Lymphopenia; Neonatal Screening; Severe Combined Immunodeficiency
PubMed: 34537207
DOI: 10.1016/j.jaci.2021.08.026 -
The Cochrane Database of Systematic... Aug 2012The consequences of influenza in children and adults are mainly absenteeism from school and work. However, the risk of complications is greatest in children and people... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The consequences of influenza in children and adults are mainly absenteeism from school and work. However, the risk of complications is greatest in children and people over 65 years of age.
OBJECTIVES
To appraise all comparative studies evaluating the effects of influenza vaccines in healthy children, assess vaccine efficacy (prevention of confirmed influenza) and effectiveness (prevention of influenza-like illness (ILI)) and document adverse events associated with influenza vaccines.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 3) which includes the Acute Respiratory Infections Group's Specialised Register, OLD MEDLINE (1950 to 1965), MEDLINE (1966 to November 2011), EMBASE (1974 to November 2011), Biological Abstracts (1969 to September 2007), and Science Citation Index (1974 to September 2007).
SELECTION CRITERIA
Randomised controlled trials (RCTs), cohort and case-control studies of any influenza vaccine in healthy children under 16 years of age.
DATA COLLECTION AND ANALYSIS
Four review authors independently assessed trial quality and extracted data.
MAIN RESULTS
We included 75 studies with about 300,000 observations. We included 17 RCTs, 19 cohort studies and 11 case-control studies in the analysis of vaccine efficacy and effectiveness. Evidence from RCTs shows that six children under the age of six need to be vaccinated with live attenuated vaccine to prevent one case of influenza (infection and symptoms). We could find no usable data for those aged two years or younger.Inactivated vaccines in children aged two years or younger are not significantly more efficacious than placebo. Twenty-eight children over the age of six need to be vaccinated to prevent one case of influenza (infection and symptoms). Eight need to be vaccinated to prevent one case of influenza-like-illness (ILI). We could find no evidence of effect on secondary cases, lower respiratory tract disease, drug prescriptions, otitis media and its consequences and socioeconomic impact. We found weak single-study evidence of effect on school absenteeism by children and caring parents from work. Variability in study design and presentation of data was such that a meta-analysis of safety outcome data was not feasible. Extensive evidence of reporting bias of safety outcomes from trials of live attenuated influenza vaccines (LAIVs) impeded meaningful analysis. One specific brand of monovalent pandemic vaccine is associated with cataplexy and narcolepsy in children and there is sparse evidence of serious harms (such as febrile convulsions) in specific situations.
AUTHORS' CONCLUSIONS
Influenza vaccines are efficacious in preventing cases of influenza in children older than two years of age, but little evidence is available for children younger than two years of age. There was a difference between vaccine efficacy and effectiveness, partly due to differing datasets, settings and viral circulation patterns. No safety comparisons could be carried out, emphasising the need for standardisation of methods and presentation of vaccine safety data in future studies. In specific cases, influenza vaccines were associated with serious harms such as narcolepsy and febrile convulsions. It was surprising to find only one study of inactivated vaccine in children under two years, given current recommendations to vaccinate healthy children from six months of age in the USA, Canada, parts of Europe and Australia. If immunisation in children is to be recommended as a public health policy, large-scale studies assessing important outcomes, and directly comparing vaccine types are urgently required. The degree of scrutiny needed to identify all global cases of potential harms is beyond the resources of this review. This review includes trials funded by industry. An earlier systematic review of 274 influenza vaccine studies published up to 2007 found industry-funded studies were published in more prestigious journals and cited more than other studies independently from methodological quality and size. Studies funded from public sources were significantly less likely to report conclusions favourable to the vaccines. The review showed that reliable evidence on influenza vaccines is thin but there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies. The content and conclusions of this review should be interpreted in the light of this finding.
Topics: Adolescent; Case-Control Studies; Child; Child, Preschool; Cohort Studies; Conflict of Interest; Humans; Infant; Influenza Vaccines; Influenza, Human; Numbers Needed To Treat; Randomized Controlled Trials as Topic; Research Support as Topic; Vaccines, Attenuated; Vaccines, Inactivated
PubMed: 22895945
DOI: 10.1002/14651858.CD004879.pub4 -
The Cochrane Database of Systematic... Feb 2013Influenza vaccination is recommended for asthmatic patients in many countries as observational studies have shown that influenza infection can be associated with asthma... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Influenza vaccination is recommended for asthmatic patients in many countries as observational studies have shown that influenza infection can be associated with asthma exacerbations. However, influenza vaccination has the potential to cause wheezing and adversely affect pulmonary function. While an overview concluded that there was no clear benefit of influenza vaccination in patients with asthma, this conclusion was not based on a systematic search of the literature.
OBJECTIVES
The objective of this review was to assess the efficacy and safety of influenza vaccination in children and adults with asthma.
SEARCH METHODS
We searched the Cochrane Airways Group trials register and reviewed reference lists of articles. The latest search was carried out in November 2012.
SELECTION CRITERIA
We included randomised trials of influenza vaccination in children (over two years of age) and adults with asthma. We excluded studies involving people with chronic obstructive pulmonary disease.
DATA COLLECTION AND ANALYSIS
Inclusion criteria and assessment of trial quality were applied by two review authors independently. Data extraction was done by two review authors independently. Study authors were contacted for missing information.
MAIN RESULTS
Nine trials were included in the first published version of this review, and nine further trials have been included in four updates. The included studies cover a wide diversity of people, settings and types of influenza vaccination, and we pooled data from the studies that employed similar vaccines. PROTECTIVE EFFECTS OF INACTIVATED INFLUENZA VACCINE DURING THE INFLUENZA SEASON: A single parallel-group trial, involving 696 children, was able to assess the protective effects of influenza vaccination. There was no significant reduction in the number, duration or severity of influenza-related asthma exacerbations. There was no difference in the forced expiratory volume in one second (FEV) although children who had been vaccinated had better symptom scores during influenza-positive weeks. Two parallel-group trials in adults did not contribute data to these outcomes due to very low levels of confirmed influenza infection. ADVERSE EFFECTS OF INACTIVATED INFLUENZA VACCINE IN THE FIRST TWO WEEKS FOLLOWING VACCINATION: Two cross-over trials involving 1526 adults and 712 children (over three years old) with asthma compared inactivated trivalent split-virus influenza vaccine with a placebo injection. These trials excluded any clinically important increase in asthma exacerbations in the two weeks following influenza vaccination (risk difference 0.014; 95% confidence interval -0.010 to 0.037). However, there was significant heterogeneity between the findings of two trials involving 1104 adults in terms of asthma exacerbations in the first three days after vaccination with split-virus or surface-antigen inactivated vaccines. There was no significant difference in measures of healthcare utilisation, days off school/symptom-free days, mean lung function or medication usage.EFFECTS OF LIVE ATTENUATED (INTRANASAL) INFLUENZA VACCINATION: There were no significant differences found in exacerbations or measures of lung function following live attenuated cold recombinant vaccine versus placebo in two small studies on 17 adults and 48 children. There were no significant differences in asthma exacerbations found for the comparison live attenuated vaccine (intranasal) versus trivalent inactivated vaccine (intramuscular) in one study on 2229 children (over six years of age).
AUTHORS' CONCLUSIONS
Uncertainty remains about the degree of protection that vaccination affords against asthma exacerbations that are related to influenza infection. Evidence from more recently published randomised trials of inactivated split-virus influenza vaccination indicates that there is no significant increase in asthma exacerbations immediately after vaccination in adults or children over three years of age. We were unable to address concerns regarding possible increased wheezing and hospital admissions in infants given live intranasal vaccination.
Topics: Adult; Asthma; Child; Disease Progression; Humans; Influenza Vaccines; Influenza, Human; Randomized Controlled Trials as Topic; Vaccines, Inactivated
PubMed: 23450529
DOI: 10.1002/14651858.CD000364.pub4 -
PLoS Neglected Tropical Diseases May 2020Brucellosis is a neglected zoonotic disease of remarkable importance worldwide. The focus of this systematic review was to investigate occupational brucellosis and to... (Meta-Analysis)
Meta-Analysis
Brucellosis is a neglected zoonotic disease of remarkable importance worldwide. The focus of this systematic review was to investigate occupational brucellosis and to identify the main infection risks for each group exposed to the pathogen. Seven databases were used to identify papers related to occupational brucellosis: CABI, Cochrane, Pubmed, Scielo, Science Direct, Scopus and Web of Science. The search resulted in 6123 studies, of which 63 were selected using the quality assessment tools guided from National Institutes of Health (NIH) and Case Report Guidelines (CARE). Five different job-related groups were considered greatly exposed to the disease: rural workers, abattoir workers, veterinarians and veterinary assistants, laboratory workers and hunters. The main risk factors and exposure sources involved in the occupational infection observed from the analysis of the articles were direct contact with animal fluids, failure to comply with the use of personal protective equipment, accidental exposure to live attenuated anti-brucellosis vaccines and non-compliance with biosafety standards. Brucella species frequently isolated from job-related infection were Brucella melitensis, Brucella abortus, Brucella suis and Brucella canis. In addition, a meta-analysis was performed using the case-control studies and demonstrated that animal breeders, laboratory workers and abattoir workers have 3.47 [95% confidence interval (CI); 1.47-8.19] times more chance to become infected with Brucella spp. than others individuals that have no contact with the possible sources of infection. This systematic review improved the understanding of the epidemiology of brucellosis as an occupational disease. Rural workers, abattoir workers, veterinarians, laboratory workers and hunters were the groups more exposed to occupational Brucella spp. infection. Moreover, it was observed that the lack of knowledge about brucellosis among frequently exposed professionals, in addition to some behaviors, such as negligence in the use of individual and collective protective measures, increases the probability of infection.
Topics: Abattoirs; Animals; Brucella; Brucellosis; Humans; Laboratory Personnel; Occupational Diseases; Occupational Exposure; Veterinarians
PubMed: 32392223
DOI: 10.1371/journal.pntd.0008164