Katherine R. Sabourin

Epstein-Barr virus (EBV) is an etiologic agent of endemic Burkitt lymphoma (BL), a prevalent pediatric cancer in sub-Saharan Africa. There are two known types of EBV, EBV Type-1 (EBV-1) and EBV Type-2 (EBV-2), both found in eBL patients. To determine the EBV load and type dynamics within the tonsils, saliva, whole blood, and plasma, we enrolled 102 children aged 1–14 undergoing tonsillectomy in a malaria holoendemic region of western Kenya. Additionally, we investigated EBV-2 cell type preference in tonsillar mononuclear cells (TMCs). Saliva, whole blood, and tonsillar tissue were collected at the time of enrollment. Whole blood was centrifuged to separate plasma from red blood cells, and tonsillar mononuclear cells (TMCs) were isolated from tonsils using a ficoll gradient. Using qPCR, we assessed EBV load and type in TMCs, plasma, whole blood, and saliva. Additionally, a subset of samples was subject to cell sorting to determine the infected cell population. We found that EBV loads were significantly higher in TMCs compared to whole blood ( P < 0.01) and in saliva compared to plasma ( P < 0.01). Children with EBV-2 exhibited higher EBV loads in TMCs ( P = 0.016) than those with EBV-1. Both EBV types were detected in T-cells isolated from TMCS and were also observed in different compartments within the same individual. Our findings indicate that EBV-2 infection in tonsils is associated with higher viral loads, consistent with a model where EBV-2 has more lytic replication compared to EBV-1. IMPORTANCE: This study investigates Epstein-Barr virus (EBV) persistence in children residing in a malaria-endemic region of western Kenya. We examined the dynamic interplay of EBV viral load and type distribution across multiple host compartments: tonsils, saliva, whole blood, and plasma. Our key finding reveals significantly higher viral loads in pediatric tonsils infected with EBV-2 compared to EBV-1, providing novel insights into the phenotypic differences between EBV-1 and EBV-2. This suggests a greater propensity for lytic replication in EBV-2. We also observed the presence of both EBV types within the same individual, but in different compartments. Understanding the dynamics of EBV persistence, particularly the association of EBV-2 with increased tonsillar viral loads, is crucial. This knowledge sheds light on the pathophysiology of EBV infections and may indicate more severe or prolonged infections in affected children, ultimately contributing to improved risk assessment and management of EBV-associated diseases.

Background: Epstein–Barr virus (EBV) infection is ubiquitous and in sub-Saharan Africa, occurs early in life. In a population-based rural African cohort, we leveraged historical samples from the General Population Cohort (GPC) in Uganda to examine the epidemiology of infection with EBV over time, in the era of HIV. Methods: We used 9024 serum samples collected from the GPC in 1992, 2000, 2008, from 7576 participants across the age range (0–99 years of age) and tested for anti-EBV immunoglobulin G (IgG) antibodies to EAd, VCA, and EBNA-1 using a multiplex bead-based assay. The related gammaherpesvirus, Kaposi’s sarcoma-associated herpesvirus (KSHV) seropositivity was also determined by detection of anti-KSHV IgG antibodies to K8.1 or ORF73 measured by recombinant protein enzyme-linked immunosorbent assay. Data on sex, age, and HIV serostatus were also collected. EBV seropositivity was modeled with age (excluding those under one year, who may have had maternal antibodies), sex, HIV serostatus, and KSHV serostatus using generalized linear mixed effects models to produce beta estimates. Results: More than 93% of children were EBV seropositive by one year of age. EBV seropositivity was significantly associated with KSHV seropositivity. Anti-EBNA-1 antibody levels decreased with increasing age and were lower on average in people living with HIV. In general, anti-EAd antibody levels increased with age, were higher in males and KSHV seropositive persons, but decreased over calendar time. Anti-VCA antibody levels increased with age and with calendar time and were higher in KSHV seropositive persons but lower in males. Conclusions: This is the first study to identify factors associated with EBV antibodies across the entire life-course in rural sub-Saharan Africa. Consistent with other studies, EBV was near ubiquitous in the population by age one year. Patterns of antibodies show changes by age, sex and calendar time, but no association with HIV was evident, suggesting no relationship between EBV sero-epidemiology and the spread of HIV in the population over time in Uganda.

We identified whether maternal HIV infection during pregnancy affects transplacental transfer of Kaposi’s sarcoma-associated herpesvirus (KSHV) specific antibodies and subsequent infant infection. We followed pregnant Kenyan women through delivery and their infants until age two years. Children were classified as HIV-exposed uninfected (HEU) or HIV-unexposed uninfected (HUU) based on maternal HIV status. Maternal venous and cord blood at delivery and child venous blood every six months were tested for antibodies to 20 KSHV antigens by multiplex bead-based immunoassay. Multiple comparisons were adjusted using false discovery rate (FDR). Maternal HIV infection was significantly associated with decreased transplacental transfer of antibodies against all KSHV antigens and lower cord blood levels for eight antigens at FDR pin utero, KSHV seroconversion in Kenyan children occurred early; associated factors must be identified.

Introduction: Most Zimbabweans access medical care through tiered health systems. In 2013, HIV care was decentralized to primary care clinics; while oncology care remained centralized. Most persons in Zimbabwe with Kaposi sarcoma (KS) are diagnosed late in their disease, and the prognosis is poor. Little is known about whether educational interventions could improve KS outcomes in these settings.Methods: Interventions to improve KS detection and management were evaluated at eight Zimbabwe primary care sites (four rural/four urban) that provided HIV care. Interventions included a standardized KS clinical evaluation tool, palliative care integration, standardized treatment and improved consultative services. Interventions were implemented between February 2013 and January 2016 using a randomized stepped‐wedge cluster design. Sites were monitored for KS diagnosis rates and KS outcomes, including early diagnosis (T0 vs. T1 tumour stage), participant retention and mortality. Analyses controlled for within‐clinic correlations.Results: A total of 1102 persons with suspected KS (96% HIV positive) were enrolled: 47% incident (new diagnosis), 20% prevalent (previous diagnosis) and 33% determined as not KS. Early (T0) diagnosis increased post‐intervention, though not significant statistically (adjusted odds ratio [aOR] = 1.48 [95% confidence interval (95% CI): 0.66–3.79], p = 0.37). New KS diagnosis rates increased 103% (95% CI: 11–273%), p = 0.02) post‐intervention; although paired with an increased odds of incorrectly diagnosing KS (aOR = 2.08 [95% CI: 0.33–3.24], p = 0.001). Post‐intervention, non‐significant decreases in 90‐day return rates (adjusted hazard ratio [aHR] = 0.69 [95% CI: 0.38–1.45], p = 0.21) and survival (aHR = 1.36 [95% CI: 0.85–2.20], p = 0.20) were estimated.Conclusions: KS training interventions at urban and rural Zimbabwe decentralized primary care clinics significantly increased overall and incorrect KS diagnosis rates, but not early KS diagnosis rates, 90‐day return rates or survival.

The association of autism spectrum disorder (ASD) with self-reported maternal cannabis use from 3 months pre-conception to delivery (“peri-pregnancy”) was assessed in children aged 30–68 months, born 2003 to 2011. Children with ASD (N = 1428) were compared to children with other developmental delays/disorders (DD, N = 1198) and population controls (POP, N = 1628). Peri-pregnancy cannabis use was reported for 5.2% of ASD, 3.2% of DD and 4.4% of POP children. Adjusted odds of peri-pregnancy cannabis use did not differ significantly between ASD cases and DD or POP controls. Results were similar for any use during pregnancy. However, given potential risks suggested by underlying neurobiology and animal models, further studies in more recent cohorts, in which cannabis use and perception may have changed, are needed.

Objectives: Define the seroprevalence and risk factors for SARS-CoV-2 antibodies in Arapahoe County, Colorado first responders (eg, law enforcement, human services, fire departments). Methods: Two hundred sixty four first responders were enrolled June to July 2020. SARS-CoV-2 seropositivity was defined as detection of immunoglobulin G (IgG) antibodies to both spike receptor binding domain and nucleocapsid in venous blood by validated enzyme-linked immunosorbent assay. We compared risk factors for being seropositive versus seronegative. Results: 4% (11/264) were SARS-CoV-2 seropositive. Seropositive participants were significantly more likely to have lung disease (% seropositive, % seronegative; P-value) (36%, 8%; P = 0.01), prior SARS-CoV-2/COVID-19 testing (36%, 8%; P ≤ 0.01), a prior positive result (18%, less than 1%), and to believe they previously had COVID-19 (64%, 15%; P < 0.01). Only 15% of those believing they had COVID-19 had anti-SARS-CoV-2 antibodies. Conclusions: Human services employees and individuals with lung disease are at SARS-CoV-2 exposure risk. Few individuals believed they had COVID-19 had prior exposure.

We aimed to determine whether Plasmodium falciparum infection affects age of Kaposi sarcoma-associated herpesvirus (KSHV) seroconversion in Kenyan children. Kenyan children (n = 144) enrolled at age 1 month, from 2 sites with different levels of malaria transmission (stable/high vs unstable/low) were followed to age 24 months. Plasma was tested for KSHV antibodies using enzyme-linked immunosorbent assay (ELISA; K8.1 and LANA) and a multiplex bead-based assay (K8.1, K10.5, ORF38, ORF50, and LANA) and whole blood tested for P. falciparum DNA using quantitative PCR. Cox proportional hazards models were used to assess associations between P. falciparum DNA detection, malaria annualized rate (P. falciparum detections/person-years), and enrollment site (malaria-high vs malaria-low) with time to KSHV seroconversion. KSHV seroprevalence was 63% by age 2 years when assessed by multiplex assay. Children with P. falciparum were at increased hazards of earlier KSHV seroconversion and, among children with malaria, the hazard of becoming KSHV seropositive increased significantly with increasing malaria annualized rate. Children from the malaria-high transmission region had no significant difference in hazards of KSHV seroconversion at 12 months but were more likely to become KSHV seropositive by age 24 months. Malaria exposure increases the risk for KSHV seroconversion early in life.

Background: Kaposi sarcoma-associated herpesvirus (KSHV) seroprevalence in sub-Saharan African children can range up to 50% by age 2 years but factors affecting early age of KSHV infection are not well understood. Malaria during pregnancy has been associated with hindered transplacental transfer of antibodies to several pathogens but whether it affects transplacental transfer of KSHV antibodies is unknown. We aimed to determine if in utero malaria exposure reduced the transfer of KSHV antibodies across the placenta. Methods: A cohort study in Kisumu, Kenya enrolled pregnant women at their first antenatal clinic (ANC) visit and followed them through delivery. We included 70 KSHV-positive, HIV-negative mothers and their children. KSHV antibody levels were measured by ELISA (K8.1, ORF73) and multiplex assay (K8.1, ORF73, K10.5, ORF38, ORF50). Transplacental transfer of antibodies was measured by the cord to maternal blood ratio (CMR) of KSHV antibodies. Malaria during pregnancy was defined as detection of Plasmodium falciparum (Pf) DNA at any ANC visit or delivery. Among women with malaria during pregnancy, we examined time of last malaria infection prior to delivery (< 27 vs. 27+ weeks gestation) and malaria incidence rate (MIR) (episodes/100 person-weeks). Results: KSHV seroprevalence (positive for K8.1 or ORF73 by ELISA) among pregnant women was 88%. Neither malaria during pregnancy, malaria infection timing, nor MIR were associated with maternal delivery KSHV antibody blood levels. Maternal delivery and cord blood KSHV antibody levels were highly correlated but these correlations did not differ by malaria during pregnancy. KSHV transplacental antibody transfer was not associated with malaria during pregnancy, malaria infection timing, nor MIR. Conclusions: Malaria during pregnancy does not appear to affect transfer of KSHV antibodies across the placenta.

Maternal infection and fever during pregnancy have been implicated in the etiology of autism spectrum disorder (ASD); however, studies have not been able to separate the effects of fever itself from the impact of a specific infectious organism on the developing brain. We utilized data from the Study to Explore Early Development (SEED), a case–control study among 2‐ to 5‐year‐old children born between 2003 and 2006 in the United States, to explore a possible association between maternal infection and fever during pregnancy and risk of ASD and other developmental disorders (DDs). Three groups of children were included: children with ASD (N = 606) and children with DDs (N = 856), ascertained from clinical and educational sources, and children from the general population (N = 796), randomly sampled from state birth records. Information about infection and fever during pregnancy was obtained from a telephone interview with the mother shortly after study enrollment and maternal prenatal and labor/delivery medical records. ASD and DD status was determined by an in‐person standardized developmental assessment of the child at 3–5 years of age. After adjustment for covariates, maternal infection anytime during pregnancy was not associated with ASD or DDs. However, second trimester infection accompanied by fever elevated risk for ASD approximately twofold (aOR = 2.19, 95% confidence interval 1.14–4.23). These findings of an association between maternal infection with fever in the second trimester and increased risk of ASD in the offspring suggest that the inflammatory response to the infectious agent may be etiologically relevant. Autism Res 2019, 12: 1551–1561. © 2019 International Society for Autism Research, Wiley Periodicals, Inc.Lay Summary: Using data from a large multisite study in the United States—the Study to Explore Early Development—we found that women who had an infection during the second trimester of pregnancy accompanied by a fever are more likely to have children with ASD. These findings suggest the possibility that only more severe infections accompanied by a robust inflammatory response increase the risk of ASD.