Tetanus and Diphtheria Seroprotection among Children Younger Than 15 Years in Nigeria, 2018: Who Are the Unprotected Children?

Serological surveys provide an objective biological measure of population immunity, and tetanus serological surveys can also assess vaccination coverage. We undertook a national assessment of immunity to tetanus and diphtheria among Nigerian children aged <15 years using stored specimens collected during the 2018 Nigeria HIV/AIDS Indicator and Impact Survey, a national cross-sectional household-based survey. We used a validated multiplex bead assay to test for tetanus and diphtheria toxoid-antibodies. In total, 31,456 specimens were tested. Overall, 70.9% and 84.3% of children aged <15 years had at least minimal seroprotection (≥0.01 IU/mL) against tetanus and diphtheria, respectively. Seroprotection was lowest in the north west and north east zones. Factors associated with increased tetanus seroprotection included living in the southern geopolitical zones, urban residence, and higher wealth quintiles (p < 0.001). Full seroprotection (≥0.1 IU/mL) was the same for tetanus (42.2%) and diphtheria (41.7%), while long-term seroprotection (≥1 IU/mL) was 15.1% for tetanus and 6.0% for diphtheria. Full- and long-term seroprotection were higher in boys compared to girls (p < 0.001). Achieving high infant vaccination coverage by targeting specific geographic areas and socio-economic groups and introducing tetanus and diphtheria booster doses in childhood and adolescence are needed to achieve lifelong protection against tetanus and diphtheria and prevent maternal and neonatal tetanus.

Antibody escape and global spread of SARS-CoV-2 lineage A.27.

In spring 2021, an increasing number of infections was observed caused by the hitherto rarely described SARS-CoV-2 variant A.27 in south-west Germany. From December 2020 to June 2021 this lineage has been detected in 31 countries. Phylogeographic analyses of A.27 sequences obtained from national and international databases reveal a global spread of this lineage through multiple introductions from its inferred origin in Western Africa. Variant A.27 is characterized by a mutational pattern in the spike gene that includes the L18F, L452R and N501Y spike amino acid substitutions found in various variants of concern but lacks the globally dominant D614G. Neutralization assays demonstrate an escape of A.27 from convalescent and vaccine-elicited antibody-mediated immunity. Moreover, the therapeutic monoclonal antibody Bamlanivimab and partially the REGN-COV2 cocktail fail to block infection by A.27. Our data emphasize the need for continued global monitoring of novel lineages because of the independent evolution of new escape mutations.

Effectiveness of bladder tumor antigen quantitative test in the diagnosis of bladder carcinoma in a schistosoma endemic area.

INTRODUCTION: Bladder carcinoma is the most common male cancer in our environment due to endemicity of schistosomiasis. Squamous-cell carcinoma is the most common histological type and patients present at an advanced stage. The objective of this study is to compare the sensitivity, specificity, and predictive values of the bladder tumor antigen quantitative test (BTA TRAK) and urine cytology in the diagnosis of bladder carcinoma in a schistosoma endemic area. MATERIALS AND METHODS: This is a 12-month cross-sectional study of 88 patients, 52 of them with features of bladder carcinoma as study group, and 36 of them with hematuria from other urologic conditions, and benign urologic conditions and healthy volunteers as control group (CG). The mean ages of patients in the study and CGs were 47.17 ± 17.00 and 44.19 ± 18.89 years, respectively (P = 0.412). Bladder tumor antigen was assayed using enzyme-linked immunosorbent assay. Data were analyzed using SPSS version 20.0 for Windows. RESULTS: The sensitivity of urine cytology and BTA TRAK in the study was 29.1% and 98.8%, respectively. The specificity of urine cytology and BTA TRAK was 95.5% and 13.6%, respectively (P = 0.05). The positive predictive values of urine cytology and BTA TRAK in the study were 96.2% and 81.7%, respectively. The negative predictive values were 25.0% and 75.0% for urine cytology and BTA TRAK, respectively. CONCLUSION: BTA TRAK is more sensitive but poorly specific as compared to that of the urine cytology for bladder cell carcinoma detection in a schistosoma endemic area.