Browsing by Subject "Seroprevalence"

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    Human papillomavirus seroprevalence and seroconversion following baseline detection of nine human papillomavirus types in young women
    (Elsevier, 2022) Brown, Darron R.; Castellsagué, Xavier; Ferris, Daron; Garland, Suzanne M.; Huh, Warner; Steben, Marc; Wheeler, Cosette M.; Saah, Alfred; Luxembourg, Alain; Li, Se; Velicer, Christine; Medicine, School of Medicine
    Background: Estimates of the humoral immune response to incident human papillomavirus (HPV) infections are limited. Methods: In this post hoc analysis of 3875 women aged 16-23 years from a 4-valent HPV vaccine trial (NCT00092482), HPV seroprevalence on day 1 was measured with a 9-valent HPV (HPV 6/11/16/18/31/33/45/52/58) competitive Luminex immunoassay and compared with cervical/external genital HPV detection by polymerase chain reaction. In the control group, among women who were HPV DNA‒negative on day 1, seroconversion following initial HPV detection was estimated using Kaplan-Meier methods. Results: Type-specific HPV seropositivity among women with no day 1 cervical/external genital HPV detection was 0.6%-3.6%. Women with any 9-valent HPV (9vHPV) cervical/external genital detection (796/3875; 20.5%) had concordant seropositivity ranging from 13.4% (HPV 45) to 38.5% (HPV 6). Among women in the control group who were negative for all HPV types on day 1, seroconversion by month 30 after initial detection ranged from 29% (HPV 45) to 75% (HPV 16). Conclusions: Humoral immune response to HPV is variable and dynamic, depending on type-specific exposure. This longitudinal analysis provides insight into the relationship between incident infection and seropositivity.
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    Seroprevalence of antibodies to SARS-CoV-2 among blood donors in the early month of the pandemic in Saudi Arabia
    (Elsevier, 2020) Banjar, Ayman; Al-Tawfiq, Jaffar A.; Alruwaily, Amaal; Alserehi, Haleema; Al-Qunaibet, Ada; Alaswad, Rehab; Almutlaq, Hind; Almudaiheem, Abdullah; Khojah, Abdullah T.; Alsaif, Faisal; Almolad, Shaza Karim; Alqahtani, Saeed; AlJurayyan, Abdullah; Alotaibi, Abdullah; Almalki, Safar; Abuhaimed, Yousef; Alkhashan, Abdullah; Alfaifi, Amal; Alabdulkareem, Khaled; Jokhdar, Hani; Assiri, Abdullah; Almudarra, Sami; Medicine, School of Medicine
    Background: Serologic testing provides better understanding of SARS-CoV-2 prevalence and its transmission. This study was an investigation of the prevalence of antibodies to SARS-CoV-2 among blood donors in Saudi Arabia. Objective: To estimate the seroprevalence of anti-SARS-CoV-2 antibodies among blood donors in Saudi Arabia during the early phase of the COVID-19 pandemic. Methods: Serology results and epidemiological data were analyzed for 837 adult blood donors, with no confirmed SARS-CoV-2 infection, in Saudi Arabia from 20th to 25th May 2020. Seroprevalence was determined using electrochemical immunoassay to detect anti-SARS-CoV-2 antibodies. Results: The overall seroprevalence of anti-SARS-CoV-2 antibodies was 1.4% (12/837). Non-citizens had higher seroprevalence compared with citizens (OR 13.6, p = 0.001). Secondary education was significantly associated with higher seroprevalence compared with higher education (OR 6.8, p = 0.005). The data showed that the highest seroprevalence was in Makkah (8.1%). Uisng Makkah seroprevalence as the reference, the seroprevalence in other areas was: Madinah 4.1% (OR 0.48, 95% CI 0.12-1.94), Jeddah 2.3% (OR 0.27, 95% CI 0.31-2.25), and Qassim 2.9 % (OR 0.34, 95% CI 0.04-2.89) and these were not statistically different from seroprevalence in the Makkah region. Conclusions: At the early months of the COVID-19 pandemic in Saudi Arabia, the seroprevalence of antibodies to SARS-CoV-2 among blood donors was low, but was higher among non-citizens. These findings may indicate that non-citizens and less educated individuals may be less attentive to preventive measures. Monitoring seroprevalence trends over time require repeated sampling.