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1.
Topics in Antiviral Medicine ; 31(2):440, 2023.
Article in English | EMBASE | ID: covidwho-2320115

ABSTRACT

Background: The pandemic response measures have had significant global economic and health impacts with transient reductions in HIV clinic attendance and self-reported anti-retroviral therapy (ART) adherence reported in prior studies. Since viral suppression (VS) is an indication of ART adherence and effective service delivery, we assessed VS in the context of the COVID-19 pandemic in 3 African countries Methods: Since 2013, the African Cohort Study (AFRICOS) has enrolled individuals 18 years or older with and without HIV, in an approximate 5:1 ratio, at 12 clinics across 5 HIV care programs in Tanzania Uganda, Kenya, and Nigeria. For people living with HIV (PLWH), ART history was extracted from medical records and viral load was assessed at each visit. This assesses VS (< 1000 c/ml) before and during the COVID-19 pandemic (categorized into 4 surges and a consolidated non-surge period;defined in Table 1) among PLWH. Tanzania was excluded due to inadequate pandemic data. Logistic regression with generalized estimating equations, clustered by participant, was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) comparing VS before and during COVID-19. Models are adjusted for age, sex, and program. Result(s): Of the 1741 study participants, 368 are from Uganda, 1156 are from Kenya, and 217 are from Nigeria;730 are males, 1011 are females, and 147 are under the age of 30. PLWH were less likely to be virally suppressed during the first surge period (OR 0.85, CI 0.46-1.56), but VS significantly increased during the second surge period (OR 1.95, CI 1.23-3.04) compared to the pre-COVID period. The third and fourth surge periods also saw a higher VS (table 1). Females are more likely to be virally suppressed than males (OR 1.58, CI 1.09- 2.29) and PLWH ages 40-49 have higher VS (OR 2.43, CI 1.32-4.48) compared to PLWH under. PLWH at the AFRICOS sites in Kenya and Nigeria show lower VS than the Ugandan cohort (ORs 0.46, CI 0.26-0.79 and OR 0.32, CI 0.17-0.60 respectively). Conclusion(s): The initial drop in VS may be attributed to reduced clinic access due to lockdowns. Many HIV programs supported by the President's Emergency Plan for AIDS Relief (PEPFAR) adapted their strategies to serve PLWH by scaling up community ART dispensing and multi-month dispensing (MMD) of ART for stable clients, which could have led to increased VS during the other surge periods.

2.
Topics in Antiviral Medicine ; 31(2):137-138, 2023.
Article in English | EMBASE | ID: covidwho-2316561

ABSTRACT

Background: Pre-existing coronavirus-specific antibody responses may affect SARS-CoV-2 responses. We evaluated longitudinal samples obtained before and during the pandemic in participants from Kenya, Nigeria, Tanzania and Uganda;90% were people living with HIV. Method(s): Serum samples were tested using a multiplex bead-based immunoassay to measure antibody binding against 22 antigens including Nucleocapsid (N) and Spike (S) proteins of the 7 human coronaviruses and one malaria antigen. Result(s): We tested 819 longitudinal samples from 80 participants collected between July 2013 and May 2021 (3-16 samples per participant). Using a signal to noise ratio (S/N) >10, 13, 1, and 5 participants showed at least one time point with IgG responses to S of SARS-CoV-2 (ancestral), SARS-CoV-1 and MERS-CoV respectively while 14, 8, and 11 participants showed responses to N before 2020. Across individuals, IgG binding to SARS-CoV-2 S subunit S2 was most frequently detected and it showed the highest within-host fluctuations over time. A few individuals had elevated responses that persisted over years towards multiple antigens, most frequently to different SARS-CoV-2 antigens and rarely to distinct viruses. One individual showed high RBD-specific IgG responses to distinct coronaviruses at a single time point before 2020. Responses against coronaviruses measured post-2020 generally correlated with responses measured before 2020, except for a subset of infected individuals whose responses against SARS-CoV-2 dramatically increased post-pandemic. IgG responses against the ancestral SARS-CoV-2 variant were most correlated with responses against Alpha and Gamma (then to Beta and Delta, rho >0.75) variants. Using an IgM S/N >10, 31 participants were Malaria positive and 22 showed concurrent elevated coronavirus IgM responses. However, about half of the malaria positive participants had no IgG responses against any coronavirus antigen and the rest presented limited and variable patterns of association between responses against coronaviruses and malaria. Conclusion(s): Our study confirmed that a small subset of individuals in Africa had long-lasting IgG coronavirus-specific antibodies before the pandemic. While there was an association between coronavirus IgM responses and responses against malaria, there was no correlation between IgG responses and malaria infection. Further analysis is needed to better understand the interactions between antigens in the development of antibody immunity to coronaviruses. (Table Presented).

3.
Topics in Antiviral Medicine ; 30(1 SUPPL):102-103, 2022.
Article in English | EMBASE | ID: covidwho-1880510

ABSTRACT

Background: COVID-19 clinical manifestations range from asymptomatic to severe disease. Prior immune responses to human coronaviruses may affect individual responses to SARS-CoV-2. We surveyed coronavirus responses pre-pandemic in individuals from Kenya, Nigeria, Tanzania, Uganda and Thailand;81% were people living with HIV. Methods: Specimens were screened for SARS-CoV-2 Spike S2 subunit IgG responses. Selected samples were tested using a bead-based immunoassay that profiled the specificity, isotype and subclass of antibody responses to coronavirus, flavivirus and HIV antigens. Wilcoxon rank sum tests were performed to compare responses across antigens and participant group. Results: We screened 1,875 samples (one per individual) collected between 2013 and October 2019: 1,630 samples were from Africa (87%) and 245 from Thailand. 6.99% of participants (n=131, 116 from Africa (89%) and 15 from Thailand) showed responses above the naïve signal threshold and were further tested. Using a signal to noise ratio of >10 as a cut-off value, 44, 27 and 42 samples showed IgG responses to the Spike protein of SARS-CoV-2, SARS-CoV-1 and MERS-CoV respectively, while 7, 9 and 4 samples showed responses to Nucleocapsid for these same antigens. Some individuals had higher responses than those seen in SARS-CoV-2 convalescent individuals. We found a strikingly different pattern of reactivity in Africa compared to Thailand (Figure 1). Antibody responses were significantly higher in the African participants compared to Thai participants across antigens corresponding to SARS-CoV-2 (p<0.001), SARS-CoV-1 (p<0.001) and MERS-CoV (p<0.01). Similar patterns were seen for IgG subclasses, IgA and IgM. The difference was less pronounced for the four endemic coronaviruses, nonetheless anti-Spike responses were significantly higher in African participants for HKU1 and OC43 (p≤0.018). In addition, mapping responses to 21 flavivirus antigens showed the highest reactivity in Thailand and in Nigeria. Conclusion: Our serosurvey of pre-pandemic samples showed that there were significantly higher antibody responses against coronaviruses, including SARS-CoV-2, in Africa than in Thailand. Profiling flavivirus responses showed that the difference between the two regions was not due to a higher background reactivity across African samples. Further analysis is needed to explain pre-pandemic SARS-CoV-2-like antibody responses among African participants and explore implications for geographic diversity in disease severity.

4.
Topics in Antiviral Medicine ; 29(1):285-286, 2021.
Article in English | EMBASE | ID: covidwho-1250087

ABSTRACT

Background: The COVID-19 pandemic and national responses to mitigate this public health threat have disrupted activities of daily living with economic and health impacts globally. The extent of these disruptions is evolving. Our objectives were to characterize participants who missed study visits during the pandemic and assess the impact of COVID-19 on HIV outcomes, employment, food security and trauma among people living with HIV (PLWH). Methods: AFRICOS began enrolling adults at risk for HIV and PLWH at 12 PEPFAR-supported clinics in Tanzania, Uganda, Kenya, and Nigeria in 2013. At 6-monthly visits sociodemographic questionnaires were administered and clinical outcomes assessed. Chi-squared tests were used to describe differences between those presenting for and missing a study visit since the pandemic began, using data from participants' most recent visit before 19 March 2020. Generalized estimating equations were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) comparing social and clinical indicators before and during the pandemic. Models were adjusted for age, sex and site;food security models were also adjusted for employment status. Analyses were restricted to those with a pre-COVID-19 visit on or after 1 January 2019 and at least one visit during the pandemic. Results: As of 1 November 2020, 1023 (44.5%) of 2298 PLWH with a pre- COVID-19 visit since 1 January 2019 had a visit during the pandemic. PLWH who missed a study visit during COVID-19 were less adherent to antiretroviral therapy (ART) (70.0% vs 88.6%, p<0.001), less adherent to clinic visits (77.5% vs 95.4%, p<0.001) and a greater proportion had a viral load ≥1000 copies/mL on ART (17.5% vs 4.6%, p<0.001). Participants seen during the pandemic were less likely to be food secure (aOR: 0.57, 95% CI: 0.44 - 0.74) and more likely to have cut/reduced one or more meals per day (aOR: 1.75, 95% CI: 1.36 - 2.25;table). No significant impacts of COVID-19 were observed on clinic visit or ART adherence, employment, or Post-Traumatic Stress Disorder. Among 665 PLWH with available data, 597 (89.8%) had a ≥3-month supply of ART during COVID- 19. Conclusion: PLWH missing study visits during COVID-19 were less engaged in care prior to the pandemic. Innovations such as multi-month dispensing, telemedicine, and other differentiated service delivery strategies should be used to retain PLWH in care. During the pandemic, HIV outcomes remained stable, but food insecurity needs to be addressed.

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