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Porphyrins are intermediate metabolites involved in the biosynthesis of vital molecules, including heme, cobalamin, and chlorophyll. Bacterial porphyrins are known to be proinflammatory and are associated with biofilm formation. This study investigated porphyrin production by strains of Corynebacterium diphtheriae using emission spectroscopy, high-performance liquid chromatography with fluorescence detection, diode array detector, and mass spectrometry. Emission spectroscopy revealed characteristic porphyrin emission spectra in all strains, with coproporphyrin III predominating. Qualitative analysis by different chromatographic methods identified coproporphyrin III, uroporphyrin I, and protoporphyrin IX in all strains. Quantitative analysis revealed strain-dependent coproporphyrin III production. Further studies are required to investigate the relationship between porphyrin production and the virulence potential of Corynebacterium diphtheriae.
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Human infections with Corynebacterium diphtheriae species complex (CdSC) bacteria were rare in French Guiana until 2016, when the number of cases diagnosed increased. We conducted an epidemiologic, multicenter, retrospective study of all human CdSC infections diagnosed in French Guiana during January 1, 2016-December 31, 2021. A total of 64 infectious episodes were observed in 60 patients; 61 infections were caused by C. diphtheriae and 3 by C. ulcerans. Estimated incidence increased from 0.7 cases/100,000 population in 2016 to 7.7 cases/100,000 population in 2021. The mean patient age was 30.4 (+23.7) years, and male-to-female ratio was 1.7:1 (38/22). Of the 61 C. diphtheriae isolates, 5 tested positive for the diphtheria toxin gene, and all results were negative by Elek test; 95% (61/64) of cases were cutaneous, including the C. ulcerans cases. The increase in reported human infections underscores the need to raise awareness among frontline healthcare practitioners to improve prevention.
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Corynebacterium diphtheriae , Difteria , Humanos , Guiana Francesa/epidemiologia , Estudos Retrospectivos , Feminino , Masculino , Corynebacterium diphtheriae/isolamento & purificação , Corynebacterium diphtheriae/genética , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Difteria/epidemiologia , Difteria/microbiologia , Idoso , Incidência , Lactente , História do Século XXI , Infecções por Corynebacterium/epidemiologia , Infecções por Corynebacterium/microbiologiaRESUMO
RESUMEN Los adultos fumadores, con comorbilidades, y los ancianos tienen mayor riesgo de contraer infecciones pulmonares y de tener peor evolución. La neumonía adquirida en la comunidad debida a virus, neumococo, además de otras bacterias y microorga nismos "atípicos" afecta tanto a adultos sanos como enfermos. La vacuna antigripal se diseña el verano anterior orientada a las cepas esperadas para la temporada siguiente. Su eficacia depende fundamentalmente de la variante viral que finalmente sea la responsable del brote. La vacuna anti-neumocócica polisacárida existe desde 1983 y será inexorablemente reemplazada por vacunas conjugadas de mayor eficacia, que previenen la infección por los serotipos presentes en la vacuna. La inmunización contra SARS-CoV-2 aceleró la reducción del contagio y la gravedad de COVID-19 notablemente. La vacuna acelular para Bordetella pertussis no está en el calendario de adultos, aun cuando vacunarlos fortalece el control del contagio infantil. La vacunas doble bacteriana (difteria y tétanos), y triple (doble + pertusis), y contra sarampión, varicela, rubeola, HPV, Haemophylus influenzae, meningococo, herpes zóster, fiebre hemorrágica argentina y fiebre amarilla están disponibles, pero son de uso limitado. Nuevas vacunas, como la recientemente aprobada por los CDC contra el virus sincicial respiratorio, pronto estarán disponibles.
ABSTRACT Adult smokers, subjects with comorbidities, and the elderly are at higher risk of pulmo nary infections and worse outcomes. Community-acquired pneumonia due to viruses, pneumococcus, other bacteria, and "atypical" microorganisms affects healthy and sick adults. The flu vaccine is designed the previous summer for the strains expected for the following season. Its effectiveness depends fundamentally on the viral variant ultimately responsible for the outbreak. The anti-pneumococcal polysaccharide vaccine has been available since 1983 and it is expected to be replaced by conjugate vaccines which are more effective in preventing infection due to serotypes present in the vaccine. Immuniza tion against SARS-CoV-2 diminished contagion and severity of COVID-19 remarkably. The acellular vaccine for Bordetella pertussis is not on the schedule for all adults, even when vaccinating them strengthens the control of contagion in children. Double bacterial (diphtheria and tetanus), triple (double + pertussis), measles, varicella, rubella, HPV, Haemophilus influenzae, meningococcal, herpes zoster, Argentine hemorrhagic fever, and yellow fever vaccines are available, but their use is limited. New vaccines such as the one recently approved by the CDC against respiratory syncytial virus will soon be available.
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El tétanos es una enfermedad aguda, potencialmente mortal, que se caracteriza por rigidez generalizada y espasmos convulsivos de los músculos esqueléticos. Es causado por una bacteria anaerobia formadora de esporas, Clostridium tetani. Sus esporas, la forma latente del microorganismo, se encuentran en suelos contaminados con excrementos de animales y humanos (1), en la superficie de la piel y de herramientas oxidadas como clavos, agujas, alambre de púas, etc. Las esporas son muy resistentes al calor y a la mayoría de los antisépticos y pueden sobrevivir durante años. La difteria, antes de la introducción de la vacuna en los años 1930-1940, era altamente endémica y tenía alta mortalidad. Durante este período, se observaban picos regulares de la enfermedad y era una de las principales causas de muerte en la población. Los individuos mayores de 15 años que sobrevivían desarrollaban inmunidad la cual era duradera. En el periodo de 1950-1970, la vacuna comenzó a distribuirse ampliamente en todos los países, lo que resultó en una disminución significativa de la mortalidad y la endemicidad de la enfermedad. Sin embargo, en países con bajos índices de desarrollo y coberturas vacunales deficientes, se siguieron observando brotes esporádicos, principalmente debido a adultos susceptibles sin vacunación. Entre 1980 y 2000, la situación post-vacunal mostró una endemicidad nula, con una baja mortalidad y la ausencia de picos o brotes en la mayoría de los países con programas de inmunización establecidos. No obstante, en países sin un programa de vacunación establecido, la difteria continúa presentándose en forma de brotes. En consecuencia, la enfermedad se encuentra en proceso de eliminación en muchos países, pero aún no se considera erradicada completamente.
Tetanus is an acute, life-threatening disease characterized by generalized stiffness and convulsive spasms of skeletal muscles. It is caused by an anaerobic spore-forming bacteria. Clostridium tetani. Its spores, the latent form of the microorganism, are found in soil contaminated with animal and human excrement. (1), on the surface of the skin and rusty tools such as nails, needles, barbed wire, etc. The spores are very resistant to heat and most of antiseptics and can survive for years. Diphtheria, before the introduction of the vaccine in the 1930s-1940s, was highly endemic and had high mortality. During this period, regular peaks of the disease were observed and it was one of the main causes of death in the population. Individuals over 15 years of age who survived They developed immunity which was long-lasting. In the period 1950-1970, The vaccine began to be distributed widely in all countries, which resulted in a significant decrease in mortality and endemicity of the illness. However, in countries with low development rates and poor vaccine coverage, sporadic outbreaks continued to be observed, mainly due to susceptible adults without vaccination. Between 1980 and 2000, the post-vaccine situation showed zero endemicity, with low mortality and the absence of peaks or outbreaks in most countries with established immunization programs. However, in countries without an established vaccination program, diphtheria continues to occur in the form of buds. Consequently, the disease is in the process of elimination in many countries, but is not yet considered eradicated. completely.
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Tétano , DifteriaRESUMO
BACKGROUND: Argentina currently uses a pentavalent vaccine containing diphtheria, tetanus, pertussis (whole cell), Haemophilus influenza type b and hepatitis B antigens, administered concomitantly with the inactivated polio vaccine (IPV) (DTwP-Hib-HB plus IPV) in its childhood vaccination schedule. However, hexavalent vaccines containing acellular pertussis antigens (DTaP-Hib-HB-IPV) and providing protection against the same diseases are also licensed, but are only available with a private prescription or for high-risk pre-term infants in the public health program. We analyzed the cost of switching from the current schedule to the alternative schedule with the hexavalent vaccine in Argentina, assuming similar levels of effectiveness. METHODS: The study population was infants ≤ 1 year of age born in Argentina from 2015 to 2019. The analysis considered adverse events, programmatic, logistic, and vaccine costs of both schemes from the societal perspective. The societal costs were disaggregated to summarize costs incurred in the public sector and with vaccination pre-term infants in the public sector. Costs were expressed in 2021 US Dollars (US$). RESULTS: Although the cost of vaccines with the alternative scheme would be US$39.8 million (M) more than with the current scheme, these additional costs are in large part offset by fewer adverse event-associated costs and lower programmatic costs such that the overall cost of the alternative scheme would only be an additional US$3.6 M from the societal perspective. The additional cost associated with switching to the alternative scheme in the public sector and with the vaccination of pre-term infants in the public sector would be US$2.1 M and US$84,023, respectively. CONCLUSIONS: The switch to an alternative scheme with the hexavalent vaccine in Argentina would result in marginally higher vaccine costs, which are mostly offset by the lower costs associated with improved logistics, fewer separate vaccines, and a reduction in adverse events.
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Coqueluche , Lactente , Humanos , Vacinas Combinadas , Coqueluche/prevenção & controle , Argentina , Vacina contra Difteria, Tétano e Coqueluche , Vacina Antipólio de Vírus Inativado , Vacinas contra Hepatite B , Custos e Análise de Custo , Esquemas de ImunizaçãoRESUMO
National vaccination programmes recommend the influenza vaccine for older adults, but this population group has the greatest morbidity and mortality from other preventable vaccine diseases. The aim of this article is to estimate the vaccine coverage in adults aged 65 years and older and to analyse the factors that could increase or decrease vaccination uptake probability for the three listed vaccines in the national vaccination programme (influenza, tetanus and diphtheria, and pneumococcus) and the full scheme in Mexico. We conducted an analytical cross-sectional study with 2012, 2018, and 2021 rounds from the National Health and Nutrition Survey, in which we calculated the vaccine coverage estimations and performed multivariable logistic regression models to analyse the factors related to vaccine uptake. Tetanus and diphtheria vaccines had the greatest coverage estimation in all years (59-71%), whereas the pneumococcus vaccine had the lowest (32-53%). Full scheme vaccine coverage decreased from 37.80% to 24.77% in 2012 and 2021, respectively. The National Health Card property, morbidity, being a beneficiary of any health system institution, and use of preventive services increased the probability of vaccine uptake. In conclusion, vaccine coverage in older Mexican adults decreased over time, and the Mexican health system plays a strategic role in immunisation.
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Difteria , Vacinas contra Influenza , Tétano , Cobertura Vacinal , Idoso , Humanos , Estudos Transversais , Difteria/epidemiologia , Difteria/prevenção & controle , México/epidemiologia , Tétano/epidemiologia , Tétano/prevenção & controle , Toxoide Tetânico , VacinaçãoRESUMO
INTRODUCTION: Worldwide, tetanus-diphtheria-acellular pertussis (Tdap) vaccination coverage of healthcare professionals (HCPs) is below 40%, but this data is not available for Brazil. We hypothesize that a high number of HCPs are not immune to pertussis in Brazil. Main objective was to determine the seroprevalence of anti-pertussis toxin (anti-PT IgG) among HCPs. Secondary objectives were to evaluate Tdap vaccination coverage, to assess predictive factors associated with anti-PT IgG, and to estimate the decay of anti-PT IgG and time to Tdap vaccination. METHODS: Observational cross-sectional serological study in 352 HCPs who worked at São Paulo Hospital - Federal University of São Paulo (UNIFESP) in 2020, approved by UNIFESP Ethics Committee. Data collected included sociodemographics, knowledge about Tdap, and vaccination status. Anti-PT IgG were quantified by ELISA: <10 IU/mL seronegative and ≥ 10-1000 IU/mL seropositive. Titers ≥ 10-50 IU/mL were classified low positivity, indicating no recent B. pertussis infection or Tdap vaccination; >50 IU/mL high positivity, indicating recent B. pertussis infection or Tdap vaccination, and > 100 IU/mL as acute B. pertussis infection or Tdap vaccination in the previous year. Comparisons were done by Chi-square test, multivariable logistic regression, and Pearsons correlation, at 5% p-level. RESULTS: 331/352 HCPs were not aware the Brazilian National Immunization Program recommends Tdap for all HCPs and pregnant women. 68/339 HCPs received Tdap (mean 3.1 ± 2.0 years). 55/352 were seronegative for pertussis, all unvaccinated. 56/271 with no history of Tdap vaccination had high positivity. The probability of anti-PT IgG > 50 IU/mL was 11.5 times higher in Tdap vaccinated HCPs than in non-vaccinated (p < 0.001). There was a weak but significant correlation between anti-PT IgG and interval of Tdap vaccination (r = 0.404; p = 0.001). Anti-PT IgG dropped 5 IU/mL/year (p = 0.001). CONCLUSION: Better education of HCPs on needs and benefits of Tdap vaccination is critical. Goals must be to improve HCPs vaccination coverage.
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Vacinas contra Difteria, Tétano e Coqueluche Acelular , Difteria , Tétano , Coqueluche , Humanos , Feminino , Gravidez , Cobertura Vacinal , Brasil/epidemiologia , Estudos Transversais , Estudos Soroepidemiológicos , Coqueluche/prevenção & controle , Vacinação , Anticorpos Antibacterianos , Difteria/prevenção & controle , Imunoglobulina G , Tétano/prevenção & controle , Atenção à SaúdeRESUMO
Background: Corynebacterium silvaticum is a pathogenic, gram-positive bacterial species that causes caseous lymphadenitis in wild boars, domestic pigs and roe deer in Western Europe. It can affect animal production and cause zoonosis. Genome analysis has suggested that one strain from Portugal and one from Austria could probably produce the diphtheria toxin (DT), which inhibits protein synthesis and can cause death. Methods: To further investigate the species genetic diversity and probable production of DT by Portuguese strains, eight isolates from this country were sequenced and compared to 38 public ones. Results: Strains from Portugal are monophyletic, nearly identical, form a unique cluster and have 27 out of 36 known Corynebacterium virulence or niche factors. All of them lack a frameshift in the tox gene and were suggested to produce DT. A phylogenetic analysis shows that the species has diverged into two clades. Clade 1 is composed of strains that were suggested to have the ability to produce DT, represented by the monophyletic strains from Portugal and strain 05-13 from Austria. Clade 2 is composed of strains unable to produce DT due to a frameshifted tox gene. The second clade is represented by strains from Austria, Germany and Switzerland. Ten genome clusters were detected, in which strains from Germany are the most diverse. Strains from Portugal belong to an exclusive cluster. The pangenome has 2,961 proteins and is nearly closed (α = 0.968). Exclusive genes shared by clusters 1 and 2, and Portuguese strains are probably not related to disease manifestation as they share the same host but could play a role in their extra-host environmental adaptation. These results show the potential of the species to cause zoonosis, possibly diphtheria. The identified clusters, exclusively shaded genes, and exclusive STs identified in Portugal could be applied in the identification and epidemiology of the species.
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Cervos , Toxina Diftérica , Suínos , Animais , Toxina Diftérica/genética , Portugal/epidemiologia , Filogenia , Cervos/metabolismo , Corynebacterium , Sus scrofa/metabolismo , ZoonosesRESUMO
Diphtheria is an acute infectious disease caused by Corynebacterium diphtheria, producer of the diphtheric toxin. The aim of this paper is to demonstrate the importance of establishing the humanitarian end point in the potency test of antidiphtheric serum. The protective capacity of diphtheria serum is established under the lethal effect of a fixed dose of diphtheric toxin through potency testing in albino guinea pigs (Cavia porcellus), English strain. The potency test is routinely performed in the Biological Quality Control - In Vivo for the purpose of releasing batches of antidiphtheric sera by the Butantan Institute. In the potency test, some guinea pigs show signs of disease and after the onset of symptoms it is impossible to observe any reversal in the effects caused by the disease, therefore, with the introduction of humane endpoint, the guinea pigs are removed from the test, already in the second stage of disease progression, without harming the final result, but reducing the suffering and stress of animals being tested, promoting comfort to the animals. The Biological Quality Control - In Vivo introduced the humanitarian end point in the potency test of antidiphtheria serum, promoting a refinement of the potency test, using one of the pillars of the 3R's, adding quality to the tests.
A difteria é uma doença infecciosa aguda causada pelo Corynebacterium diphtheria, produtor da toxina diftérica. Esse trabalho tem como objetivo demonstrar a importância do estabelecimento do ponto final humanitário no teste de potência do soro antidifitérico. A capacidade protetora do soro antidiftérico é estabelecida sob o efeito letal de uma dose fixa de toxina diftérica através do teste de potência em Cobaias Albinas (Cavia porcellus), variedade inglesa. Rotineiramente o teste de potência é realizado no Controle de Qualidade Biológico - In Vivo com a finalidade de liberar lotes de soros antidiftéricos pelo Instituto Butantan. No teste de potência, algumas cobaias, apresentam sinais de adoecimento e após o início dos sintomas é impossível observar no quadro qualquer reversão nos efeitos ocasionados pela doença, portanto, com a introdução da finalização humanitária, tem-se a retirada prévia das cobaias do teste, já no segundo estágio de evolução da doença, sem prejudicar o resultado final, contudo reduzindo o sofrimento e o estresse dos animais em teste, promovendo conforto aos animais. O Controle de Qualidade Biológico – In Vivo introduziu o ponto final humanitário no teste de potência do soro antidiftérico promovendo um refinamento do teste de potência, utilizando-se um dos pilares do 3R’s agregando qualidade aos testes.
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Data recently reported by our group indicate that stimulation with a pool of immunogens capable of eliciting type 2 immune responses can restore the cognitive and behavioral dysfunctions recorded after a single episode of non-severe rodent malaria caused by Plasmodium berghei ANKA. Here we explored the hypothesis that isolated immunization with one of the type 2 immune response-inducing immunogens, the human diphtheria-tetanus (dT) vaccine, may revert damages associated with malaria. To investigate this possibility, we studied the dynamics of cognitive deficits and anxiety-like phenotype following non-severe experimental malaria and evaluated the effects of immunization with both dT and of a pool of type 2 immune stimuli in reversing these impairments. Locomotor activity and long-term memory deficits were assessed through the open field test (OFT) and novel object recognition task (NORT), while the anxiety-like phenotype was assessed by OFT and light/dark task (LDT). Our results indicate that poor performance in cognitive-behavioral tests can be detected as early as the 12th day after the end of antimalarial treatment with chloroquine and may persist for up to 155 days post infection. The single immunization strategy with the human dT vaccine showed promise in reversal of long-term memory deficits in NORT, and anxiety-like behavior in OFT and LDT.
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Transtornos Cognitivos , Disfunção Cognitiva , Humanos , Imunomodulação , Vacina contra Difteria e Tétano , Imunidade , CogniçãoRESUMO
Background: The literature on the association between religion and immunization coverage is scant, mostly consisting of single-country studies. Analyses in low and middle-income countries (LMICs) to assess whether the proportions of zero-dose children vary according to religion remains necessary to better understand non-socioeconomic immunization barriers and to inform interventions that target zero-dose children. Methods: We included 66 LMICs with standardized national surveys carried out since 2010, with information on religion and vaccination. The proportion of children who failed to receive any doses of a diphtheria-pertussis-tetanus (DPT) containing vaccine - a proxy for no access to routine vaccination or "zero-dose" status - was the outcome. Differences among religious groups were assessed using a test for heterogeneity. Additional analyses were performed controlling for the fixed effect of country, household wealth, maternal education, and urban-rural residence to assess associations between religion and immunization. Findings: In 27 countries there was significant heterogeneity in no-DPT prevalence according to religion. Pooled analyses adjusted for wealth, maternal education, and area of residence showed that Muslim children had 76% higher no-DPT prevalence than Christian children. Children from the majority religion in each country tended to have lower no-DPT prevalence than the rest of the population except in Muslim-majority countries. Interpretation: Analyses of gaps in coverage according to religion are relevant to renewing efforts to reach groups that are being left behind, with an important role in the reduction of zero-dose children.
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Cobertura Vacinal , Vacinas , Criança , Humanos , Países em Desenvolvimento , Prevalência , RendaRESUMO
The World Health Organization (WHO) recommends a minimum of 90% coverage of diphtheria three-dose complete vaccination scheme (DPT) as part of routine immunization programs in children. However, diphtheria coverage in Peru has not reached the minimum recommended during the last decades. Our study aimed to determine the complete three-dose DPT coverage and factors associated with compliance towards complete vaccination in Peru between 2010-2019. We conducted a secondary cross-sectional study using the "Encuesta Demográfica y de Salud Familiar (ENDES)"- Demographic and Family Health Survey, which is a survey that targets mothers between 15 and 49 years of age. DPT vaccination coverage was 72.4% and several factors were associated with the DPT scheme completion. Women in the age groups 18 to 24 (ORa = 2.31, 95%CI: 2.11-2.52), 25 to 34 (ORa = 3.37, 95% CI: 3.08-3.69), and 35 to 49 (ORa = 4.74, 95% CI: 4.29-5.22) were more likely to complete their children's DPT vaccination scheme compared to those between 15 to 17 years of age. Both Spanish (ORa = 1.39, 95% CI: 1.31-1.48) and Quechua (ORa = 1.34, 95% CI: 1.25-1.43) as first spoken language were associated with DPT completion compared to native language speaking mothers. Women who worked (ORa = 1.72, 95% CI: 1.57-1.88), studied (ORa = 1.47, 95% CI: 1.33-1.62), or were housewives (ORa = 1.41, 95% CI: 1.29-1.54) during the previous week were more likely to complete their children's DPT scheme compared to participants that did not work during the previous week. Women with the financial capability to access health care were less likely to complete the DPT scheme (ORa = 0.95, 95% CI: 0.92-0.97). Considering the accessibility to health care centers, women who knew the nearest location (ORa = 1.07, 95% CI: 1.03-1.11), had geographic accessibility (ORa = 1.09, 95% CI: 1.06-1.13) or a current transport (ORa = 1.06, 95% CI: 1.02-1.09) were more likely to complete their children 's DPT scheme. Our results highlight low diphtheria vaccine coverage levels in Peru, with values lower than what is recommended by the WHO. Results may serve as a baseline for future studies to improve vaccination programs, reduce barriers and increase DPT coverage in Peru.
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Ordered mesoporous silica (OMS) was proved to be an efficient oral adjuvant capable to deliver a wide in size variety of different antigens, promoting efficient immunogenicity. This material can be used in single or polivalent vaccines, which have been developed by a group of Brazilian scientists. The experiments performed with the model protein Bovine Serum Albumin (BSA) gave the first promissing results, that were also achieved by testing the virus like particle surface antigen of hepatitis B (HBsAg) and diphtheria anatoxin (dANA). Nanostructured OMS, SBA-15 type, with bi-dimensional hexagonal porous symmetry was used to encapsulate the antigens either in the mesoporous (pore diameter â¼ 10 nm) or macroporous (pore diameter > 50 nm) regions. This silica vehicle proved to be capable to create an inflammatory response, did not exhibit toxicity, being effective to induce immunity in high and low responder mice towards antibody production. The silica particles are in the range of micrometer size, leaving no trace in mice organs due to its easy expulsion by faeces. The methods of physics, usually employed to characterize the structure, composition and morphology of materials are of fundamental importance to develop proper oral vaccines in order to state the ideal antigen load to avoid clustering and to determine the rate of antigen release in different media mimicking body fluids.
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Dióxido de Silício , Vacinas , Adjuvantes Imunológicos , Animais , Antígenos , Antígenos de Superfície da Hepatite B , Camundongos , Porosidade , Dióxido de Silício/químicaRESUMO
The tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine is recommended during pregnancy for neonatal protection against pertussis, although little is known of the protection it provides against diphtheria. The work used a cross-sectional design to estimate seroprevalence against diphtheria in 805 pregnant women with ≥37 gestation weeks and their newborns whose deliveries were attended in eight hospitals randomly chosen from a subregion of Antioquia, Colombia and to explore factors related with maternal protection. Levels of IgG antibodies were determined by using a commercial enzyme-linked immunosorbent assay test. Placental transfer of antibodies and crude and adjusted prevalence ratio (aPR) were analyzed to describe factors related with maternal protection against diphtheria. Protection against diphtheria was observed in 91.7% (95% CI 90.3-93.0) of the pregnant women and 93.1% (95% CI 91.7-94.4) of newborns, whose antibody levels were positively correlated (Spearman's r = 0.769; p = 0.000). Maternal protection could be influenced by having been vaccinated during the current pregnancy (aPR 0.85, 95% CI: 0.82-0.93). The protective effect of vaccination during pregnancy and the efficiency of maternal antibody transfers were detected. Public health efforts should focus on increasing Tdap vaccination during each pregnancy to protect mothers and newborns against diphtheria.
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PURPOSE: This study aims to compare protection against diphtheria and tetanus conferred on the mother and the neonate before and after maternal vaccination against tetanus, diphtheria, and acellular pertussis (Tdap), transfer of antibodies, and the variables that could impact on the protection. MATERIALS AND METHODS: The study followed a cohort of 200 pregnant women from a region in Colombia, contacted during prenatal control before vaccination and upon delivery. The work determined immunoglobulin G antibodies against diphtheria and tetanus of pregnant women and umbilical cord. The proportion of protection, the geometric mean of the concentration, and the transfer of maternal antibodies were calculated. The protection profile of the pregnant women was explored by using multiple correspondence analysis. RESULTS: The concentration of antibodies against diphtheria was significant before and after vaccination of the pregnant women (p=0.000) with proportions of 85.0% and 97.5%, respectively, and of 98.6% in the umbilical cord, with significant antibody correlation (Spearman's coefficient=0.668, p=0.01). Sero-protection against tetanus before vaccination was at 71.0%, after at 92.6%, and in the umbilical cord at 95.9%, with significant antibody concentration before and after vaccination (p=0.000) and antibody correlation (Spearman's coefficient=0.936, p=0.01). Sero-protection was higher when the pregnant women were vaccine 8 to 11 weeks before delivery. Unprotected pregnant women were those not vaccinated during pregnancy. CONCLUSION: The high proportion of protection against diphtheria and tetanus and the placental transfer support the need to promote maternal immunization with Tdap.
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Resumen El tétanos continúa siendo un problema de salud pública, y que afecta a todas las edades. La mortalidad aumenta por bajas coberturas de vacunación y escasez de recursos para un tratamiento temprano. Es causado por la toxina de Clostridium tetani (tetanoespasmina) el cual ingresa al organismo a través de heridas contaminadas por cuerpos extraños. La clínica más frecuente del tétanos es del tipo generalizado y se caracteriza por la contracción tónica de músculos esqueléticos, espasmos musculares intensos, dolorosos, e hiperactividad autonómica. El diagnóstico es principalmente clínico. Se presenta el caso clínico de un tétanos generalizado en un niño con vacunación incompleta. Se discute la importancia de la vacunación y el diagnóstico y tratamiento precoz para mejorar el pronóstico de la enfermedad.
Abstract Tetanus continues to be a public health problem, which affects all age groups. Mortality increases when immunization programs have low coverage and there is a lack of resources for early treatment. This disease is caused by the toxin of Clostridium tetani (tetanospasmin) which enters the body via wounds contaminated by foreign bodies. The most common symptoms of tetanus are of the generalized type and are characterized by tonic contraction of skeletal muscles, intense, painful muscle spasms, and autonomic hyperactivity. The diagnosis is clinical and the previous vaccination history becomes important. We report the case of generalized tetanus in a child with incomplete immunizations. Highlight the importance of vaccination and early diagnosis and treatment.
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Routine immunization against diphtheria and tetanus has drastically reduced the incidence of these diseases worldwide. Anti-diphtheria/tetanus vaccine has in general aluminum salt as adjuvant in its formulation that can produce several adverse effects. There is a growing interest in developing new adjuvants. In this study, we evaluated the efficiency of SBA-15 as an adjuvant in subcutaneous immunization in mice with diphtheria (dANA) and tetanus (tANA) anatoxins as well as with the mixture of them (dtANA). The tANA molecules and their encapsulation in SBA-15 were characterized using Small-Angle X-ray Scattering (SAXS), Dynamical Light Scattering (DLS), Nitrogen Adsorption Isotherm (NAI), Conventional Circular Dichroism (CD)/Synchrotron Radiation Circular Dichroism (SRCD) Spectroscopy, and Tryptophan Fluorescence Spectroscopy (FS). The primary and secondary antibody response elicited by subcutaneous immunization of High (HIII) and Low (LIII) antibody responder mice with dANA, tANA, or dtANA encapsulated in the SBA-15 were determined. We demonstrated that SBA-15 increases the immunogenicity of dANA and tANA antigens, especially when administered in combination. We also verified that SBA-15 modulates the antibody response of LIII mice, turning them into high antibody responder. Thus, these results suggest that SBA-15 may be an effective adjuvant for different vaccine formulations.
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Ordered mesoporous silica was proved to be an efficient oral adjuvant capable to deliver a wide in size variety of different antigens, promoting efficient immunogenicity. This material can be used in single or polivalent vaccines, which have been developed by a group of Brazilian scientists. The experiments performed with the model protein Bovine Serum Albumin (BSA) gave the first promissing results, that were also achieved by testing the virus like particle surface antigen of hepatitis B (HBsAg) and diphtheria anatoxin (dANA). Nanostructured ordered mesoporous silica, SBA-15 type, with bi-dimensional hexagonal porous symmetry was used to encapsulate the antigens either in the mesoporous (pore diameter ~10 nm) or macroporous ( pore diameter > 50 nm) regions. This silica vehicle proved to be capable to create an inflammatory response, did not exhibit toxicity, being effective to induce immunity in high and low responder mice towards antibody production. The silica particles are in the range of micrometer size, leaving no trace in mice organs due to its easy expulsion by faeces. The methods of Physics, usually employed to characterize the structure, composition and morphology of materials are of fundamental importance to develop proper oral vaccines in order to state the ideal antigen load to avoid clustering and to determine the rate of antigen release in different media mimicking body fluids.
RESUMO
Diphtheria is a vaccine-preventable disease, yet immunization can wane over time to non-protective levels. We have developed a low-cost, miniaturized electroanalytical biosensor to quantify anti-diphtheria toxin (DTx) immunoglobulin G (anti-DTx IgG) antibody to minimize the risk for localized outbreaks. Two epitopes specific to DTx and recognized by antibodies generated post-vaccination were selected to create a bi-epitope peptide, biEP, by synthesizing the epitopes in tandem. The biEP peptide was conjugated to the surface of a pencil-lead electrode (PLE) integrated into a portable electrode holder. Captured anti-DTx IgG was measured by square wave voltammetry from the generation of hydroquinone (HQ) from the resulting immunocomplex. The performance of the biEP reagent presented high selectivity and specificity for DTx. Under the optimized working conditions, a logarithmic calibration curve showed good linearity over the concentration range of 10-5-10-1 IU mL-1 and achieved a limit of detection of 5 × 10-6 IU mL-1. The final device proved suitable for interrogating the immunity level against DTx in actual serum samples. Results showed good agreement with those obtained from a commercial enzyme-linked immunosorbent assay. In addition, the flexibility for conjugating other capture molecules to PLEs suggests that this technology could be easily adapted to the diagnoses of other pathogens.
Assuntos
Técnicas Biossensoriais , Toxina Diftérica , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Imunoensaio , Imunoglobulina G/química , Imunoglobulina G/imunologiaRESUMO
Abstract Objective: To assess the protective effect of exclusive breastfeeding and the effectiveness of maternal vaccination in reducing pertussis-like illness. Method: This was a case-control study conducted in sentinel hospitals for pertussis in Recife between July 2016 and July 2018. Cases included children aged under six months with symptoms compatible with pertussis (pertussis-like illness). Controls included children aged under six months, living in the metropolitan region of Recife with no diagnosis of pertussis-like illness and matched by the same hospital and birth date. Results: Seventy-three cases and 194 controls were included. The diagnosis of pertussis-like illness was predominantly clinical (97,2%). Amongst the main symptoms, paroxysmal cough was observed in 95.89% of cases and vomiting in 53.4%. There were 29 hospitalized cases and no deaths. Out of the 73 cases, 47 were born to mothers vaccinated against pertussis during pregnancy, and the mothers of 144 of the 194 controls had been vaccinated. The protective effect of breastfeeding was of 74% (95% CI;38%, 89%). Children younger than six months, who were exclusively breastfed and with mothers vaccinated against pertussis during pregnancy were 5 times less likely to develop pertussis-like illness, corresponding to a protection of 79% (95% CI;31%, 94%). The effectiveness of maternal vaccination against pertussis-like illness in children under six months was low (27%) and not statistically significant (CI 95%; −34% a 60%). Conclusions: Exclusive breastfeeding protects children under six months from pertussis-like illness and may be enhanced when associated with maternal vaccination. These strategies should be encouraged because they also protect against pertussis-like illnesses.