Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
2.
Int Immunopharmacol ; 100: 108095, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1377734

ABSTRACT

BACKGROUND AND AIMS: SARS-CoV-2 antibody assays are relevant in managing the COVID-19 pandemic, providing valuable data on the immunization status of the population. However, current serology tests are highly variable, due to their different characteristics and to the lack of reference materials. The aim of the World Health Organization (WHO) first International Standard (IS) for anti-SARS-CoV-2 immunoglobulin is to harmonize humoral immune response assessment after natural infection or vaccination, and recommend reporting the results for binding activity in Binding Antibody Units (BAU). MATERIALS AND METHODS: This study analyzed six commercial quantitative anti-SARS-CoV-2 S-protein assays in a head-to-head comparison, using the manufacturers' conversion factors for the WHO IS to obtain BAU/mL values. RESULTS: Our data showed good alignment up to 1000 BAU/mL, then began to disperse, exhibiting some discrepancies. Moreover, correlations among methods varied with Cohen's Kappa ranging from 0.580 to 1.00, with the lowest agreement values for kits using different target antigens or different antibody isotypes, making it clear that the laboratory report should include this information. Values expressed as BAU/ml showed a reduced between-assays variability compared to AU/ml (median coefficients of variation 0.38 and 0.68, respectively; p < 0.001). CONCLUSION: On the basis of these data at present anti-SARS CoV-2 serological assays' results are not interchangeable, and, more importantly, individual immune monitoring should be performed with the same method.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/standards , COVID-19/diagnosis , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , World Health Organization
3.
Immunol Res ; 69(6): 576-583, 2021 12.
Article in English | MEDLINE | ID: covidwho-1366407

ABSTRACT

The development of vaccines to prevent SARS-CoV-2 infection has mainly relied on the induction of neutralizing antibodies (nAbs) to the Spike protein of SARS-CoV-2, but there is growing evidence that T cell immune response can contribute to protection as well. In this study, an anti-receptor binding domain (RBD) antibody assay and an INFγ-release assay (IGRA) were used to detect humoral and cellular responses to the Pfizer-BioNTech BNT162b2 vaccine in three separate cohorts of COVID-19-naïve patients: 108 healthcare workers (HCWs), 15 elderly people, and 5 autoimmune patients treated with immunosuppressive agents. After the second dose of vaccine, the mean values of anti-RBD antibodies (Abs) and INFγ were 123.33 U/mL (range 27.55-464) and 1513 mIU/mL (range 145-2500) in HCWs and 210.7 U/mL (range 3-500) and 1167 mIU/mL (range 83-2500) in elderly people. No correlations between age and immune status were observed. On the contrary, a weak but significant positive correlation was found between INFγ and anti-RBD Abs values (rho = 0.354, p = 0.003). As to the autoimmune cohort, anti-RBD Abs were not detected in the two patients with absent peripheral CD19+B cells, despite high INFγ levels being observed in all 5 patients after vaccination. Even though the clinical relevance of T cell response has not yet been established as a correlate of vaccine-induced protection, IGRA testing has showed optimal sensitivity and specificity to define vaccine responders, even in patients lacking a cognate antibody response to the vaccine.


Subject(s)
COVID-19 Vaccines/immunology , Immunity, Cellular/immunology , Immunity, Humoral/immunology , Immunocompromised Host/immunology , SARS-CoV-2/immunology , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Autoimmune Diseases/immunology , B-Lymphocytes/immunology , COVID-19/immunology , COVID-19/prevention & control , Female , Health Personnel/statistics & numerical data , Humans , Immunogenicity, Vaccine/immunology , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Interferon-gamma/blood , Lymphocyte Count , Male , Middle Aged , Protein Domains/immunology , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocytes/immunology , Vaccination , Young Adult
6.
Int J Hyg Environ Health ; 235: 113756, 2021 06.
Article in English | MEDLINE | ID: covidwho-1230517

ABSTRACT

BACKGROUND: Schools, depending on their access to and quality of water, sanitation and hygiene (WASH) and the implementation of healthy behaviours, can be critical for the control and spread of many infectious diseases, including COVID-19. Schools provide opportunities for pupils to learn about the importance of hygiene and WASH-related practice, and build healthy habits and skills, with beneficial medium- and long-term consequences particularly in low- and middle-income countries: reducing pupils' absenteeism due to diseases, promoting physical, mental and social health, and improving learning outcomes. WASH services alone are often not sufficient and need to be combined with educational programmes. As pupils disseminate their acquired health-promoting knowledge to their (extended) families, improved WASH provisions and education in schools have beneficial effects also on the community. International organisations frequently roll out interventions in schools to improve WASH services and, in some cases, train pupils and teachers on safe WASH behaviours. How such interventions relate to local school education on WASH, health promotion and disease prevention knowledge, whether and how such knowledge and school books are integrated into WASH education interventions in schools, are knowledge gaps we fill. METHODS: We analyzed how Kenyan primary school science text book content supports WASH and health education by a book review including books used from class 1 through class 8, covering the age range from 6 to 13 years. We then conducted a rapid literature review of combined WASH interventions that included a behaviour change or educational component, and a rapid review of international policy guidance documents to contextualise the results and understand the relevance of books and school education for WASH interventions implemented by international organisations. We conducted a content analysis based on five identified thematic categories, including drinking water, sanitation, hygiene, environmental hygiene & health promotion and disease risks, and mapped over time the knowledge about WASH and disease prevention. RESULTS: The books comprehensively address drinking water issues, including sources, quality, treatment, safe storage and water conservation; risks and transmission pathways of various waterborne (Cholera, Typhoid fever), water-based (Bilharzia), vector-related (Malaria) and other communicable diseases (Tuberculosis); and the importance of environmental hygiene and health promotion. The content is broadly in line with internationally recommended WASH topics and learning objectives. Gaps remain on personal hygiene and handwashing, including menstrual hygiene, sanitation education, and related health risks and disease exposures. The depth of content varies greatly over time and across the different classes. Such locally available education materials already used in schools were considered by none of the WASH education interventions in the considered intervention studies. CONCLUSIONS: The thematic gaps/under-representations in books that we identified, namely sanitation, hygiene and menstrual hygiene education, are all high on the international WASH agenda, and need to be filled especially now, in the context of the current COVID-19 pandemic. Disconnects exist between school book knowledge and WASH education interventions, between policy and implementation, and between theory and practice, revealing missed opportunities for effective and sustainable behaviour change, and underlining the need for better integration. Considering existing local educational materials and knowledge may facilitate the buy-in and involvement of teachers and school managers in strengthening education and implementing improvements. We suggest opportunities for future research, behaviour change interventions and decision-making to improve WASH in schools.


Subject(s)
Drinking Water/standards , Health Education , Hygiene/standards , Sanitation/standards , Adolescent , Child , Communicable Disease Control , Communicable Diseases/transmission , Curriculum/statistics & numerical data , Hand Disinfection/standards , Health Behavior , Health Education/statistics & numerical data , Health Promotion , Humans , Kenya , Schools , Textbooks as Topic
7.
J Med Virol ; 93(3): 1436-1442, 2021 03.
Article in English | MEDLINE | ID: covidwho-1196450

ABSTRACT

During coronavirus disease 2019 (COVID-19) pandemic, the early diagnosis of patients is a priority. Serological assays, in particular immunoglobulin (Ig)M and IgG anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have today several applications but the interpretation of their results remains an open challenge. Given the emerging role of the IgA isotype in the COVID-19 diagnostics, we aimed to identify the SARS-CoV-2 IgA antibodies in a COVID-19 population seronegative for IgM. A total of 30 patients hospitalized in San Giovanni di Dio Hospital (Florence, Italy) for COVID-19, seronegative for IgM antibodies, have been studied for anti-SARS-CoV-2 antibodies. They all had a positive oro/nasopharyngeal swab reverse transcription-polymerase chain reaction result. Assays used were a chemiluminescent assay measuring SARS-CoV-2 specific IgM and IgG (S + N) and an ELISA, measuring specific IgG (S1) and IgA antibodies against SARS-CoV-2. Among the 30 patients, eight were positive for IgA, seven were positive for IgG (N + S), and two for IgG (S1), at the first point (5-7 days from the onset of symptoms). The IgA antibodies mean values at the second (9-13 days) and third (21-25 days) time points were even more than twice as high as IgG assays. The agreement between the two IgG assays was moderate (Cohen's K = 0.59; SE = 0.13). The inclusion of the IgA antibodies determination among serological tests of the COVID-19 diagnostic is recommended. IgA antibodies may help to close the serological gap of the COVID-19. Variations among anti-SARS-CoV-2 IgG assays should be considered in the interpretation of results.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing , COVID-19/diagnosis , Immunoglobulin A/blood , SARS-CoV-2/immunology , Adult , Aged , COVID-19/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoassay , Immunoglobulin G/blood , Immunoglobulin M/blood , Luminescent Measurements , Male , Middle Aged , Sensitivity and Specificity
10.
Riv. Ital. Med. Labor. ; 1(16): 7-17, 20200301.
Article in Italian | ELSEVIER | ID: covidwho-659439

ABSTRACT

COVID-19 infection (SARS-CoV-2) is a viral disease first encountered in Wuhan, China, in December 2019, then rapidly spreading around the world. During this current public health emergency of international concern, screening and diagnosing patients quickly in order to aid containment is a priority. Most of our knowledge on diagnostics comes from previous studies on SARSCoV. Since SARS-CoV-2 belongs to the same large family of viruses as those that cause the MERS and SARS outbreak, we could assume that its antibody generation process should be similar. The high contagiousness and the characteristics of high lethality of the epidemic require efficient diagnostics, able to quickly identify the sources of the infection. The identification of patients with active SARS-CoV-2 infection is currently based on the amplification of a viral genome sequence using molecular biology techniques (real-time polymerase chain reaction), which can be subsequently confirmed by gene sequencing. However, the variability linked to the execution of the swab and the limitations of the test (complexity, biosecurity levels, costs and long response times) makes molecular diagnostics unsuitable for use in the field. Consequently, new tools such as serological tests capable of tracking the virus through each phase of the disease are in great demand. Serological antibody tests are already being developed and have already been introduced to the market. To date, however, there is no robust scientific evidence on the clinical-diagnostic reliability of these tests which therefore, at the moment, cannot replace the molecular test. The few studies in the literature are of limited thickness, sometimes discordant with each other and conducted on a small scale mainly on the Chinese population. In the absence of specific references, there is an open debate on the best use of these serological tests and on the ideal moment of their execution. In this review we describe the main characteristics of the SARS-CoV-2 virus, the diagnostic molecular strategies available today, and the first experimental data on the determination of antibodies directed towards SARS-CoV-2.

13.
J Med Virol ; 92(9): 1671-1675, 2020 Sep.
Article in English | MEDLINE | ID: covidwho-116658

ABSTRACT

A pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading throughout the world. Though molecular diagnostic tests are the gold standard for COVID-19, serological testing is emerging as a potential surveillance tool, in addition to its complementary role in COVID-19 diagnostics. Indubitably quantitative serological testing provides greater advantages than qualitative tests but today there is still little known about serological diagnostics and what the most appropriate role quantitative tests might play. Sixty-one COVID-19 patients and 64 patients from a control group were tested by iFlash1800 CLIA analyzer for anti-SARS CoV-2 antibodies IgM and IgG. All COVID-19 patients were hospitalized in San Giovanni di Dio Hospital (Florence, Italy) and had a positive oro/nasopharyngeal swab reverse-transcription polymerase chain reaction result. The highest sensitivity with a very good specificity performance was reached at a cutoff value of 10.0 AU/mL for IgM and of 7.1 for IgG antibodies, hence near to the manufacturer's cutoff values of 10 AU/mL for both isotypes. The receiver operating characteristic curves showed area under the curve values of 0.918 and 0.980 for anti-SARS CoV-2 antibodies IgM and IgG, respectively. iFlash1800 CLIA analyzer has shown highly accurate results for the anti-SARS-CoV-2 antibodies profile and can be considered an excellent tool for COVID-19 diagnostics.


Subject(s)
Antibodies, Viral/immunology , COVID-19/diagnosis , COVID-19/immunology , Immunoassay , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Luminescent Measurements , SARS-CoV-2/immunology , Aged , Aged, 80 and over , Antibodies, Viral/blood , Automation, Laboratory , COVID-19/virology , Female , Humans , Immunoassay/methods , Immunoassay/standards , Immunoglobulin G/blood , Immunoglobulin M/blood , Luminescent Measurements/methods , Luminescent Measurements/standards , Male , Middle Aged , ROC Curve , Reproducibility of Results , Sensitivity and Specificity
SELECTION OF CITATIONS
SEARCH DETAIL
...