Immunogenicity and protection efficacy evaluation of avian paramyxovirus serotype-1 (APMV-1) isolates in experimentally infected chickens.

Vaccine failures after Newcastle disease vaccination with the current commercial vaccines have been reported and are associated with many factors, including genotypic and antigenic differences between vaccine and outbreak strains, although all APMV-1 members belong to one serotype. We assessed the immunoprotection ability of four thermostable, low-virulent Newcastle disease-virus isolates from Ugandan waterfowl against challenge with a virulent strain (MDT = 36.8 h, ICPI = 1.78) isolated from morbid chicken. Six-week-old commercial Leghorn layers, challenged at 21 days post immunization were used. Four isolates designated: NDV-133/UG/MU/2011, NDV-177/UG/MU/2011, NDV-178/UG/MU/2011 and NDV-173/UG/MU/2011 induced mean haemagglutinin inhibition antibody titres of log2 9.3, 8.2, 6.3 and 2.0, respectively, at 21 days post immunization. The antibody titres correlated with the protection rates (R² = 0.86, p < 0.007) of 60%, 50%, 20% and 0% of birds, respectively, against challenge at 14 days post challenge. Further evaluation of these and more low-virulent isolates might provide an alternative to the current commercial vaccine failures.

Sero-prevalence of syphilis and associated risk factors among pregnant women attending antenatal care at an urban-poor health centre in Kampala, Uganda: a cross-sectional study.

Introduction: syphilis and its outcomes remain a healthcare system burden with adverse consequences such as stillbirths, neonatal deaths and spontaneous abortions among others. The situation might have worsened because the COVID-19 pandemic has caused a major attention drift from other diseases. Additionally, much as testing for syphilis is a routine practice among pregnant mothers, its proportion is not known in urban health care setting. A study to determine the prevalence of syphilis among pregnant mothers in an urban poor setting is warranted. Methods: a cross-sectional study was conducted among pregnant women who attended antenatal care at Kawaala Health Centre IV in Kampala Capital City between December 2019 to March 2020. Informed consent was sought from study participants prior to data collection using structured questionnaires. Whole blood was collected and tested using SD Bioline HIV/syphilis duo rapid test kit (SD Standard Diagnostics, INC, Korea). Data analysis was done using STATA 14.2. Results: one thousand one hundred and sixty-nine pregnant women participated in the study, with a mean age of 25 years. About 27% of them had completed only primary-level education. Approximately 6% of the participants were HIV seropositive. The prevalence of syphilis was 5.9% (69/1169). HIV positivity (aOR: 4.13, 95%CI: 2.05-8.34), elevated blood pressure (aOR: 2.84, 95%CI: 1.42-5.69), and status of previous pregnancy (aOR: 0.21, 95%CI: 0.05-0.89) were significant predictors of the risk of syphilis among pregnant women in this setting. Conclusion: the prevalence of syphilis among pregnant women in urban poor settings is not low and so must not be underestimated. The potential drivers of syphilis among pregnant women are HIV, elevated blood pressure, and status of previous pregnancy. There should be increased awareness about routine syphilis testing among pregnant mothers attending antenatal care.