Publications by authors named "Chrissy Roberts"

Background: Conflict is known to impact maternal and neonatal health in Eastern Democratic Republic of the Congo (DRC), an area of longstanding insecurity. We conducted a systematic review on pregnancy and neonatal outcomes in this region to provide a comprehensive overview of maternal and neonatal outcomes over a 20-year period.

Methods: We systematically searched databases, such as Medline, EMBASE, Global Health, ClinicalTrials.

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Background: At the beginning of the 2018-2020 outbreak of Ebola virus disease (EVD) in eastern Democratic Republic of Congo (DRC), no vaccine had been licensed. However, cluster-randomized evidence from Guinea in 2015 had indicated that ring vaccination around new cases (targeting contacts and contacts-of-contacts) with the use of single-dose live-replicating rVSV-ZEBOV-GP vaccine reduced EVD rates starting 10 days after vaccination. Thus, ring vaccination was added to the standard control measures for that outbreak.

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Article Synopsis
  • The study investigated the effectiveness and safety of the rVSV-ZEBOV vaccine against Zaire Ebolavirus disease among contacts of EVD survivors, focusing on the influence of pre-existing immunity on vaccination outcomes.
  • Ten percent of participants had pre-existing antibodies, but both those with and without antibodies showed significant increases in IgG levels post-vaccination, indicating strong immune responses.
  • The findings support the vaccine's safety and suggest that pre-vaccination antibody screening is unnecessary, as it does not negatively impact the immune response to the vaccine.
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Background: Clinical severity scores can identify patients at risk of severe disease and death, and improve patient management. The modified early warning score (MEWS), the quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA), and the Universal Vital Assessment (UVA) were developed as risk-stratification tools, but they have not been fully validated in low-resource settings where fever and infectious diseases are frequent reasons for health care seeking. We assessed the performance of MEWS, qSOFA, and UVA in predicting mortality among febrile patients in the Lao PDR, Malawi, Mozambique, and Zimbabwe.

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  • Trachoma is aimed for global elimination by 2030, with a focus on using IgG antibody measurements in children for monitoring and decision-making in public health programs.
  • There are no existing guidelines for using serology in trachoma control, highlighting a larger issue in the field of disease elimination and epidemiology.
  • Researchers analyzed IgG levels in 63,911 children from various regions to determine seroconversion rates and proposed a method to assess when population transmission falls below or exceeds intervention thresholds, aiding trachoma program strategies.
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During the 2018-2020 Ebola virus disease outbreak in Democratic Republic of the Congo, a phase 3 trial of the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine (DRC-EB-001) commenced in Goma, with participants being offered the two-dose regimen given 56 days apart. Suspension of trial activities in 2020 due to the COVID-19 pandemic led to some participants receiving a late dose 2 outside the planned interval.

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  • * While fewer than 1% of non-pregnant participants faced serious adverse events (SAEs), 30.4% of pregnant women experienced SAEs, primarily due to caesarean sections, but none were linked to the vaccine.
  • * Among 1169 tracked pregnancies, there were some miscarriages, stillbirths, and low birth weights, yet the vaccine was generally well-tolerated, with a high uptake rate of 75.1%, prompting calls for more controlled trials for further insights.
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Chagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi. Clinical outcomes range from long-term asymptomatic carriage to cardiac, digestive, neurological and composite presentations that can be fatal in both acute and chronic stages of the disease. Studies of T.

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Sugar sweetened beverage consumption has been suggested as a risk factor for childhood asthma symptoms. We examined whether the UK Soft Drinks Industry Levy (SDIL), announced in March 2016 and implemented in April 2018, was associated with changes in National Health Service hospital admission rates for asthma in children, 22 months post-implementation of SDIL. We conducted interrupted time series analyses (2012-2020) to measure changes in monthly incidence rates of hospital admissions.

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Introduction: Tooth extraction due to dental caries is associated with socioeconomic deprivation and is a major reason for elective childhood hospital admissions in England. Consumption of sugar-sweetened beverages is a risk factor for dental caries. We examined whether the soft drinks industry levy (SDIL), announced in March 2016 and implemented in April 2018, was associated with changes in incidence rates of hospital admissions for carious tooth extraction in children, 22 months post-SDIL implementation.

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  • Advances in low-cost biometric technology allow for secure and efficient collection of unique biological signatures for identification and research purposes.
  • These methods are especially beneficial for individuals in resource-limited areas who lack formal identification.
  • A new open-source app has been developed to integrate biometric fingerprint capture with existing data collection platforms, significantly enhancing data accuracy and accessibility.
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  • There is evidence that inhibitory killer cell immunoglobulin-like receptors (iKIRs) can influence T cell responses and survival, particularly in chronic viral infections.
  • In a study with humans, it was found that individuals with more iKIR-ligand gene pairs had significantly longer-lasting memory CD8+ T cells, with lifespans increasing from 125 days to 250 days.
  • The research suggests that iKIR-ligand genotypes play a crucial role in T cell survival and immune aging, independent of iKIR expression on the T cells themselves.
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Class II HLA loci DRB1, DQB1 and DPB1 were typed for a total of 939 Gambian participants by locus-specific amplicon sequencing. Participants were from multiple regions of The Gambia and drawn from two studies: a family study aiming to identify associations between host genotype and trachomatous scarring (N = 796) and a cohort study aiming to identify correlates of immunity to trachoma (N = 143). All loci deviated from Hardy-Weinberg equilibrium, likely due to the family-based nature of the study: 608 participants had at least one other family member included in the study population.

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Locus-specific amplicon sequencing was used to HLA type 336 participants of Maasai ethnicity at the HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci. Participants were recruited from three study villages in North Tanzania, for the purpose of investigating risk factors for trachomatous scarring in children. Other than HLA-A, all loci significantly deviated from Hardy-Weinberg equilibrium, possibly due to high relatedness between individuals: 238 individuals shared a house with at least one another participant.

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Some social settings such as households and workplaces, have been identified as high risk for SARS-CoV-2 transmission. Identifying and quantifying the importance of these settings is critical for designing interventions. A tightly-knit religious community in the UK experienced a very large COVID-19 epidemic in 2020, reaching 64.

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  • Ebola virus disease (EVD) remains a major health issue in sub-Saharan Africa, particularly in the Democratic Republic of the Congo, prompting a clinical trial on a two-dose vaccine's effectiveness during an outbreak.
  • The trial enrolled adults and children, offering VAC52150 (Ad26.ZEBOV and MVA-BN-Filo) with doses 56 days apart, while tracking serious adverse events and assessing immune responses, especially in a subset of participants who faced delays in their vaccination.
  • Ethical approvals were secured from various health committees in the DRC, and qualitative research is being conducted through interviews and focus groups to gather insights from participants and caregivers.
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Ethnic and religious minorities have been disproportionately affected by the SARS-CoV-2 pandemic and are less likely to accept coronavirus vaccinations. Orthodox (Haredi) Jewish neighbourhoods in England experienced high incidences of SARS-CoV-2 in 2020-21 and measles outbreaks (2018-19) due to suboptimal childhood vaccination coverage. The objective of our study was to explore how the coronavirus vaccination programme (CVP) was co-delivered between public health services and an Orthodox Jewish health organisation.

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Background: Timely but accurate data collection is needed during health emergencies to inform public health responses. Often, an abundance of data is collected but not used. When outbreaks and other health events occur in remote and complex settings, operatives on the ground are often required to cover multiple tasks whilst working with limited resources.

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Approval for the use of COVID-19 vaccines has been granted in a number of countries but there are concerns that vaccine uptake may be low amongst certain groups. This study used a mixed methods approach based on online survey and an embedded quantitative/qualitative design to explore perceptions and attitudes that were associated with intention to either accept or refuse offers of vaccination in different demographic groups during the early stages of the UK's mass COVID-19 vaccination programme (December 2020). Analysis used multivariate logistic regression, structural text modeling and anthropological assessments.

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Background: As concerns about the prevalence of infections that are resistant to available antibiotics increase, attention has turned toward the use of these medicines both within and outside of formal healthcare settings. Much of what is known about use beyond formal settings is informed by survey-based research. Few studies to date have used comparative, mixed-methods approaches to render visible patterns of use within and between settings as well as wider points of context shaping these patterns.

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ODK provides software and standards that are popular solutions for off-grid electronic data collection and has substantial code overlap and interoperability with a number of related software products including CommCare, Enketo, Ona, SurveyCTO, and KoBoToolbox. These tools provide open-source options for off-grid use in public health data collection, management, analysis, and reporting. During the 2018-2020 Ebola epidemic in the North Kivu and Ituri regions of Democratic Republic of Congo, we used these tools to support the DRC Ministère de la Santé RDC and World Health Organization in their efforts to administer an experimental vaccine (VSV-Zebov-GP) as part of their strategy to control the transmission of infection.

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Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex chronic condition affecting multiple body systems, with unknown cause, unclear pathogenesis mechanisms, and fluctuating symptoms which may lead to severe debilitation. It is frequently reported to have been triggered by an infection, but there are no clear differences in exposure to, or seroprevalence of, any particular viruses between people with ME/CFS and healthy individuals. However, herpes viruses have been repeatedly hypothesized to underlie the chronic relapsing/remitting form of MS/CFS due to their persistence in a latent form with periodic reactivation.

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Background: Ethnic and religious minorities have been disproportionately affected by SARS-CoV-2 worldwide. The UK strictly-Orthodox Jewish community has been severely affected by the pandemic. This group shares characteristics with other ethnic minorities including larger family sizes, higher rates of household crowding and relative socioeconomic deprivation.

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Background: The success of a government's COVID-19 control strategy relies on public trust and broad acceptance of response measures. We investigated public perceptions of the UK government's COVID-19 response, focusing on the relationship between trust and perceived transparency, during the first wave (April 2020) of the COVID-19 pandemic in the United Kingdom.

Methods: Anonymous survey data were collected (2020-04-06 to 2020-04-22) from 9,322 respondents, aged 20+ using an online questionnaire shared primarily through Facebook.

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Background: Scarce data are available on what variables affect the risk of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the development of symptomatic COVID-19, and, particularly, the relationship with viral load. We aimed to analyse data from linked index cases of COVID-19 and their contacts to explore factors associated with transmission of SARS-CoV-2.

Methods: In this cohort study, patients were recruited as part of a randomised controlled trial done between March 17 and April 28, 2020, that aimed to assess if hydroxychloroquine reduced transmission of SARS-CoV-2.

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