Prevalence of Hepatitis B Vaccination Coverage and Serologic Evidence of Immunity Among US-Born Children and Adolescents From 1999 to 2016

IMPORTANCE

The World Health Assembly has called for the elimination of hepatitis B and C by 2030. As hepatitis B has no cure, the US strategy to eliminate hepatitis B has focused on prevention through vaccination. However, there are limited data on the trend in vaccine-associated immunity since the US implementation of universal infant hepatitis B vaccination.

OBJECTIVE

To compare self-reported hepatitis B vaccination coverage among children and adolescents with serologic evidence of immunity and infection in the US from 1999 to 2016.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016. US-born persons aged 2 to 18 years without missing hepatitis B serologic test results and with reported vaccination history were included. Data were analyzed from September 2017 to June 2018.

MAIN OUTCOMES AND MEASURES

The proportion of participants who reported complete vaccination for hepatitis B and who had positive serologic test results indicating immunity.

RESULTS

Of 21 873 children and adolescents, 51.2%% were male, and the mean (SD) age was 10.6 (4.6) years. The survey reported that hepatitis B vaccination coverage increased significantly from 1999 to 2016 (from 62.6% [95% CI, 58.6%-66.4%] to 86.3% [95% CI, 82.9%-89.2%]; P < .001). Vaccine-associated immunity also increased from 1999 to 2016 among children aged 2 to 5 years (from 60.7% [95% CI, 48.8%-71.4%] to 65.2% [95% CI, 57.4%-72.3%]; P = .001) but decreased among children aged 6 to 10 years (from 64.6% [95% CI, 57.7%-70.9%] to 46.5% [95% CI, 39.1%-54.0%]; P < .001), adolescents aged 11 to 13 years (from 68.8% [95% CI, 58.1%-77.8%] to 26.2% [95% CI, 18.6%-35.5%]; P < .001), and adolescents aged 14 to 18 years (from 68.5% [95% CI, 62.9%-73.6%] to 15.6% [95% CI, 12.2%-19.8%]; P < .001). By birth year, serologic evidence of vaccine-associated immunity significantly decreased in the 1994-2003 NHANES birth cohort but not among those born between 1988 and 1993. Non-US-born children and adolescents did not show the same decreasing trend in immunity.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, decreasing hepatitis B immunity was observed among US-born children and adolescents in the 1994-2003 NHANES birth cohort despite increasing rates of hepatitis B vaccination coverage. These findings suggest a possible need for surveillance and a booster vaccine dose for hepatitis B as those without serologic evidence of immunity become young adults and may engage in behaviors associated with an increased risk for infection.

Trends in CD4 and viral load testing 2005 to 2018: multi-cohort study of people living with HIV in Southern Africa

INTRODUCTION

The World Health Organization (WHO) recommends a CD4 cell count before starting antiretroviral therapy (ART) to detect advanced HIV disease, and routine viral load (VL) testing following ART initiation to detect treatment failure. Donor support for CD4 testing has declined to prioritize access to VL monitoring. We examined trends in CD4 and VL testing among adults (≥15 years of age) starting ART in Southern Africa.

METHODS

We analysed data from 14 HIV treatment programmes in Lesotho, Malawi, Mozambique, South Africa, Zambia and Zimbabwe in 2005 to 2018. We examined the frequency of CD4 and VL testing, the percentage of adults with CD4 or VL tests, and among those having a test, the percentage starting ART with advanced HIV disease (CD4 count <200 cells/mm3 ) or failing to suppress viral replication (>1000 HIV-RNA copies/mL) after ART initiation. We used mixed effect logistic regression to assess time trends adjusted for age and sex.

RESULTS

Among 502,456 adults, the percentage with CD4 testing at ART initiation decreased from a high of 78.1% in 2008 to a low of 38.0% in 2017; the probability declined by 14% each year (odds ratio (OR) 0.86; 95% CI 0.86 to 0.86). Frequency of CD4 testing also declined. The percentage starting ART with advanced HIV disease declined from 83.3% in 2005 to 23.5% in 2018; each year the probability declined by 20% (OR 0.80; 95% CI 0.80 to 0.81). VL testing after starting ART varied; 61.0% of adults in South Africa and 10.7% in Malawi were tested, but fewer than 2% were tested in the other four countries. The probability of VL testing after ART start increased only modestly each year (OR 1.06; 95% CI 1.05 to 1.06). The percentage with unsuppressed VL was 8.6%. There was no evidence of a decrease in unsuppressed VL over time (OR 1.00; 95% CI 0.99 to 1.01).

CONCLUSIONS

CD4 cell counting declined over time, including testing at the start of ART, despite the fact that many patients still initiated ART with advanced HIV disease. Without CD4 testing and expanded VL testing many patients with advanced HIV disease and treatment failure may go undetected, threatening the effectiveness of ART in sub-Saharan Africa.

Use and utility of serologic tests for rheumatoid arthritis in primary care

INTRODUCTION

In this retrospective, register-based population study, we evaluated if anti-citrullinated protein antibodies (ACPA) is a better choice than immunoglobulin M rheumatoid factor (IgM RF) in primary care when rheumatoid arthritis (RA) is suspected, as it determines predictive values in real-life settings. Furthermore, the study described ordering patterns to investigate the benefit of repeated testing.

METHODS

Test result, requisitioning unit, test date and the patient's social security number were collected from the Department of Clinical Immunology at Odense University Hospital in 2007-2016 and merged with patient diagnoses from the Danish National Patient Registry.

RESULTS

Overall, 5% were diagnosed with RA. IgM RF remained the preferred test during the entire period. Test sensitivity was 61% for IgM RF and 54% for ACPA. The test specificity was 88% for IgM RF and 96% for ACPA. Positive predictive value (PPV) was higher for ACPA than for IgM RF (30% versus 12%) and negative predictive value (NPV) was equal (99%) in primary care. Few individuals seroconverted from negative to positive (ACPA 2% and IgM RF 5%) and positive to negative (ACPA 3% and IgM RF 6%).

CONCLUSIONS

ACPA has a higher PPV for RA than IgM RF, whereas their NPV is identical. ACPA is the better choice when testing for RA in primary care. Seroconversion is rare, and it is only rarely relevant to retest.

FUNDING

The Department of Clinical immunology at Odense University Hospital funded the study.

TRIAL REGISTRATION

not relevant.

Rheumatologic Tests: A Primer for Family Physicians

Patients with a suspected connective tissue disorder should undergo serologic testing to confirm the diagnosis and, in some cases, to monitor disease activity and predict flares. Patients with suspected systemic lupus erythematosus should be tested for antinuclear antibodies. However, antinuclear antibodies are not specific and may be present in many other connective tissue disorders and nonrheumatologic diseases. Thus, patients with suspected systemic lupus erythematosus should undergo further testing to confirm the diagnosis. Patients with Sjögren syndrome may have a positive antinuclear antibody titer, but often also have positive anti-Sjögren antigen A or B results. Similarly, antinuclear antibodies can be present in patients with scleroderma, mixed connective tissue disease, and dermatomyositis or polymyositis. Additional tests are needed to help confirm the diagnosis. In patients with findings of rheumatoid arthritis, a positive rheumatoid factor titer suggests the diagnosis, but as with antinuclear antibodies, it is not specific and can occur in other conditions. Rheumatoid factor can also be negative in patients with rheumatoid arthritis. A positive anticyclic citrullinated peptide antibody titer is more specific for rheumatoid arthritis and can help confirm the diagnosis. Physicians should order these serologic tests only when patients have a high pretest probability of a specific connective tissue disorder.

Relevance of and New Developments in Serology for Toxoplasmosis

Toxoplasmosis is a widespread parasitic disease caused by the intracellular parasite Toxoplasma gondii with a wide spectrum of clinical outcomes. The biological diagnosis of toxoplasmosis is often difficult and of paramount importance because clinical features are not sufficient to discriminate between toxoplasmosis and other illnesses. Serological tests are the most widely used biological tools for the diagnosis of toxoplasmosis worldwide. This review focuses on the crucial role of serology in providing answers to the most important questions related to the epidemiology and diagnosis of toxoplasmosis in human pathology. Notwithstanding their undeniable importance, serological tools need to be continuously improved and the interpretation of the ensuing results remains complex in many circumstances.

Results of the National External Quality Assessment for Toxoplasmosis Serological Testing in China

Background

Toxoplasmosis is typically diagnosed by serologic testing. External quality assessment (EQA) of clinical laboratories could ensure the accuracy and reliability of serological tests. We assessed the quality of toxoplasma serological assays in Chinese clinical laboratories by an EQA performed between 2004 and 2013 by the National Center for Clinical Laboratories.

Methodology and Findings

EQA panels were prepared and shipped at room temperature to participating laboratories that employed toxoplasma IgG and IgM serological detection. By 2013, 5,384 EQA test reports for toxoplasma-specific IgM and 2,666 reports for toxoplasma-specific IgG were collected. Enzyme-linked immunosorbent (ELISA) and chemical immunofluorescent assays were the most commonly used detection methods. The overall coincidence rates of negative samples were better than those of positive samples. The overall EQA score for toxoplasma-specific IgM detection ranged between 84.3% and 99.6%. The ratio of laboratories that achieved correct IgG detection ranged from 61.1% to 99.3%. However, the inter- and intra-assay variabilities were found to be considerable. The most common problem was failure to detect low titers of antibody.

Conclusion

The EQA scheme showed an improvement in toxoplasma serological testing in China. However, further optimization of assay sensitivity to detect challenging samples remains a future challenge.

Detection of the influenza virus yesterday and now

Demographic changes and the development of transportation contribute to the rapid spread of influenza. Before an idea of a 'person to person' spread appeared, divergent theories were developed to explain influenza epidemics in the past. Intensified virological and serological tests became possible after isolation of the human influenza virus in 1933. The first influenza virus detection methods were based on its isolation in egg embryos or cell lines and on demonstration of the presence of the viral antigens. Molecular biology techniques associated with amplification of RNA improved the quality of tests as well as sensitivity of influenza virus detection in clinical samples. It became possible to detect mixed infections caused by influenza types A and B and to identify the strain of the virus. Development of reliable diagnostic methods enabled fast diagnosis of influenza which is important for choosing an appropriate medical treatment.

Changing patterns of serological testing for celiac disease in Latvia

BACKGROUND AND AIMS

A number of recent guidelines have discouraged the use of the old anti-gliadin tests for the detection of celiac disease; tissue transglutaminase IgA (tTGA) and anti-endomysial (EMA) tests are recommended instead. Our aim was to evaluate how the current recommendations have been applied in real practice. The secondary aim was to evaluate the positivity rates provided by different test types.

METHODS

We analyzed the number of celiac disease tests [anti-gliadin IgA (AGA), anti-gliadin IgG (AGG), tTGA and EMA] performed by the largest laboratory in Latvia. The analysis was performed on a yearly basis for the period between 2004 and 2009. Additionally, we analyzed the percentage of the positive test results for each of the tests.

RESULTS

The number of patients being tested for celiac disease constantly increased, with the average annual growth of 16.1%; this trend was similar both in children and in adults. The majority of patients (62.6%) were tested with anti-gliadin tests only; 27.7% were tested with either tTGA or EMA, while 9.7% were tested by a combination of the above groups. There was a substantial difference in the positivity rates of the different tests from 0.94% for EMA to 21.8% for AGG. Substantial differences were also present between various manufacturers' products.

CONCLUSION

The current guidelines and the published evidence on the proper use of serological tests for celiac disease have been slow to be applied in clinical practice; more intensive education campaigns and change in reimbursement systems could improve the situation. Nevertheless, more clinicians in Latvia are checking patients for celiac disease; this suggests an overall increased awareness.

Expression of recombinant heat-shock protein 70 of MCAN/IR/96/LON-49, a tool for diagnosis and future vaccine research

BACKGROUND

Heat shock protein 70 (HSP70) is present in all organisms studied so far, and is a major immunogen in infections caused by pathogens including Leishmania spp.

OBJECTIVE

The aim of this study was to clone and express HSP70 from L. infantum strain MCAN/IR/96/LON-49 and evaluate antibody response against HSP70 in visceral leishmaniasis (VL).

METHODS

The L. infantum HSP70 gene segment was amplified by specific primers. It was cloned into pTZ57R vector and subcloned into pET32a (+) expression vector. The new construct was transformed in the E.coli Rosetta strain, and HSP70 protein was expressed in the presence of 1 mM IPTG and purified using a HiTrap chelating column. Antibody responses against HSP70 were determined by ELISA in 37 patients with visceral leishmaniasis and 63 healthy controls.

RESULTS

Expression of HSP70 protein was confirmed using SDS-PAGE electrophoresis and dot blot with an anti-His tag antibody. There was no difference between the sequence of nucleotides of the HSP70 gene in the present study and other reported sequences. The ELISA results indicated that the sera of 81.1% (30/37) of the patients and 6.3% (5/63) of controls reacted to L. infantum HSP70.

CONCLUSION

The conservative nature of the HSP70 molecule is an advantage in vaccine studies, because of minor differences (6%) between the nucleotide sequences and consequently the similarity in amino acid sequences in various strains of L. infantum. It could therefore be used in vaccine research against leishmaniasis and also as a tool for serodiagnosis.

Recent advances in the diagnosis of childhood tuberculosis

Children account for a major proportion of the global tuberculosis disease burden, especially in endemic areas. However, the accurate diagnosis of childhood tuberculosis remains a major challenge. This review provides an overview of the most important recent advances in the diagnosis of intrathoracic childhood tuberculosis: (1) symptom-based approaches, including symptom-based screening of exposed children and symptom-based diagnosis of active disease; (2) novel immune-based approaches, including T cell assays and novel antigen-based tests; and (3) bacteriological and molecular methods that are more rapid and/or less expensive than conventional culture techniques for tuberculosis diagnosis and/or drug-resistance testing. Recent advances have improved our ability to diagnose latent infection and active tuberculosis in children, but establishing a diagnosis of either latent infection or active disease in HIV-infected children remains a major challenge, particularly in high-burden settings. Although improved access to diagnosis and treatment is essential, ultimately the burden of childhood tuberculosis is determined by the level of epidemic control achieved in a particular community. Several recent initiatives, in particular the United Nations Millennium Developmental Goals, deal with the problem of poverty and disease in a holistic fashion, but global political commitment is required to support these key initiatives.

[Laboratory advances in serologic diagnosis and research of human leptospirosis in Cuba]

For the first time in Cuba the rapid serologic technologies available worldwide were evaluated for the screening and confirmation of human leptospirosis. As its clinical recognition is difficult, the fast etiological diagnosis is of vital importance. Sensitivity and specificity values higher than 90 % were obtained in the confirmatory systems, and of 85 % in the screening systems. Of the severe patients studied by these technologies 50 % were positive. 203 cases corresponding to 4 epidemic outbreaks were confirmed, as well as 12 sick persons vaccinated with vaxSPIRAL, which demonstrates the vaccine effectiveness (78.1%). We developed and applied a latex system for a rapid screening of leptospirosis (LeptoCuba), with an excellent sensitivity, specificity, reproducibility, and stability. The application of new technologies for the screening and fast confirmation of the disease allowed to increase the positivity and quality of the diagnosis from 2000 to 2006, strengthening the microbiological surveillance in the country.

[Advances in serological systems for diagnosis of systemic fungal infections, particularly those caused by Candida and Aspergillus]

Invasive fungal infections have emerged as important causes of morbidity and mortality in neutropenicand some other immunocompromised hosts; Candida and Aspergillus are among the major pathogens in this patient population. The clinical diagnosis of these infections is not specific and the traditional mycological methods for them not sensitive, with limits in the early detection of the pathogen. The potential additives or complements to the laboratory diagnosis of invasive candidiasis and aspergillosis are two non-culture-based methods, serodiagnostic methods and molecular ones. The former methods include the detection of pathogen-specific antigens, antibodies, metabolites and cell wall components. Several have already become standard laboratory tools and some others are under active investigation for developing new, more accurate detection systems. In this review, I will discuss the current status and future potential of serodiagnostic methods, highlighting both their technical and clinical implications.

Current and future hepatitis C virus diagnostic testing: problems and advancements

Serological antibody assays used in hepatitis C virus diagnosis have improved in sensitivity and specificity. However, detection of active viremia or monitoring levels of virus during or after patient treatment is most commonly undertaken using nucleic acid-based technologies. Advancements in diagnostic technologies and implications for managing patients with hepatitis C in various clinical settings are discussed.

The United Kingdom National External Quality Assessment Scheme (blood transfusion laboratory practice): trends in proficiency and practice between 1985 and 2000

Proficiency in blood transfusion laboratory practice has improved over the last 15 years (1985-2000). Error rates for ABO grouping have fallen from 0 x 19 to 0 x 02% (P = 0 x 003). A similar trend is evident for antibody screening, with error rates for false negative antibody screens falling from 3 x 2 to 0 x 5% (P < 0 x 001), and for antibody identification, for sera containing a single alloantibody, with error rates falling from 8 x 8% to 0 x 9% over the last 10 years (P < 0 x 001). Proficiency in serological crossmatching to detect clinically significant non-ABO incompatibilities (other than Kidd), has also improved (P < 0 x 001). However, error rates for RhD grouping have not changed and there has been a recent decline in proficiency in detecting weak ABO incompatibilities and Kidd antibodies with heterozygous cells. Procedures for pretransfusion testing have also been rationalized over this time. The indirect antiglobulin test (IAT) is used in isolation by 73% of laboratories for antibody screening, and 10% rely on the direct room temperature (DRT), immediate spin (IS) crossmatch in the absence (current and/or historical) of clinically significant antibodies. Despite the improvements in error rates that have occurred alongside the rationalizations, there is still evidence of noncompliance with current published BCSH guidelines and manufacturers' instructions.

Serodiagnosis of histoplasmosis, paracoccidioidomycosis and penicilliosis marneffei; current status and future trends

Effective serodiagnosis of systemic fungal infections is of increasing importance, particularly with regard to the identification of infection with Histoplasma capsulatum, Paracoccidioides brasiliensis and Penicillium marneffei. Methodology has been based either around antibody or antigen detection, although there is clear overlap between the two. Antibody-based detection systems for the diagnosis of histoplasmosis, paracoccidioidomycosis and penicilliosis marneffei have now begun to incorporate a range of highly purified and well-characterized antigens, in contrast to the situation of a few years ago when relatively crude preparations derived from either whole cells or culture filtrate were used. The application of such antigens offers improvements in reproducibility and specificity, although the detection of meaningful antibody responses in immunosuppressed individuals remains a problem. Partly as a consequence of this a great deal of attention has focused on the development of antigen detection assays, and such methods have proved particularly successful, as for instance in the serodiagnosis of histoplasmosis in AIDS patients. The recent utilization of monoclonal antibodies in the development of antigen detection methods for the diagnosis of histoplasmosis and paracoccidioidomycosis offers further scope for improvement in this area.

Diagnostic virology--then and now

In the past five years, technologic advances in the shell vial assay and expanding availability of rapid membrane EIA tests have allowed over 90% of the viruses detected in our laboratory to be reported within 24 h postinoculation. PCR technology promises to add a new practical dimension to diagnostic virology especially for the detection of viruses in CSF, tissues, and blood. Extension of these diagnostic capabilities from investigative protocols to general laboratories for routine use will be our biggest challenge and be based on considerations of cost, licensing, and availability of this technology in "kit" formats.

New trends in the rapid serodiagnosis of leptospirosis

TR/Patoc slide test, ELISA and TIA (Thin-Layer Immunoassay) were evaluated for their use in a rapid serodiagnosis of human leptospirosis. The results obtained indicated that the TR/Patoc slide test is very sensitive and able to detect within a few minutes early antibodies against whichever serovar of leptospires, like the antigens of the Galton test. The value of the ELISA test in detecting antibodies at a low level is confirmed. The TIA assay, employed here for the first time for the diagnosis of leptospirosis, though sensitive seemed too long to perform and consequently it is not a test of choice for a rapid screening of sera.

The impact of future technology on oncologic diagnosis: oncologic imaging and diagnosis

Over the past few years, the discipline of medical imaging has entered an evolutionary period that reflects primarily the introduction of computers and digital technology into the imaging process. Clinical applications of this evolution realized to date (e.g., transmission computed tomography, ultrasound and quantitative nuclear medicine) are only indicative of future developments that promise to increase the contributions of medical imaging in a very substantial manner. This increase in the area of oncologic diagnosis is one of the more exciting possibilities existing in medicine today.

Assessment of laboratory improvement by the Center for Disease Control Diagnostic Immunology Proficiency Testing Program

The data accumulated from 1969 to 1979 in the Diagnostic Immunology portion of the Center for Disease Control Proficiency Testing Program were evaluated for evidence of change in performance among the participating laboratories. Evidence of improved performance was found for the rubella, rheumatoid factor, tularemia, quantitative immunoglobulin (immunoglobulin G, A, and M), and hepatitis B tests. No evidence of change was detected for the streptococcal enzyme, C-reactive protein, infectious mononucleosis, antinuclear antibodies, Salmonella and Brucella agglutinins, and syphilis tests. Data obtained from other tests were inadequate to determine trends. In most tests, deficiencies were identified which could be corrected and thereby could improve performance. It is pointed out that proficiency testing not only improves laboratory performance, but also can be used to evaluate performance levels, identify method, standard, or performance deficiencies, educate, estimate impact of possible changes, serve as external quality control, and document changes.

[Recent trends in the serologic diagnosis of pertussis]

Anti-whooping cough agglutinin titrations were performed in various groups of children by employing a special antigen and a microtechnique. Moderate agglutinating titers were detected in the first trimester of life and were interpreted as transmitted from the mother. Rare and moderate titers were observed in a group of children of school age, randomly selected and non institutionalized, while, on the contrary, an analogous institutionalized group showed more frequent and higher rate of antibodies. In clinically diagnosed whooping cough titers resulted high when the disease turned out to have set in more than three week earlier. Anti-whooping cough vaccination determined agglutinating titers mainly moderate and not long-lasting.