Publications by authors named "Christine A Petersen"

Background: Visceral leishmaniosis (VL) is the most severe form of human leishmaniosis, with an estimated 95% case fatality if left untreated. Dogs act as peridomestic reservoir hosts for the protozoan parasite Leishmania infantum, a causative agent for human leishmaniosis, endemic throughout the Mediterranean basin. To assure consistent and accurate surveillance of canine infection and prevent transmission to people, consistent diagnosis of canine L.

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Resident synovial macrophages (RSMs) are anti-inflammatory, self-renewing macrophages that provide physical immune sequestration of the joint space from the peripheral immune system. Increased permeability of this structure is associated with peripheral immune cells in the synovial fluid (SF). Direct measures of synovial barrier integrity are possible with tissue histology, but after barrier breakdown, if these cells perpetuate or initiate chronic inflammation in SF remains unknown.

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Background: Visceral leishmaniasis (VL), known as Kala-azar on the Indian subcontinent, is a parasitic disease caused by the flagellated protozoa Leishmania donovani and can be fatal if left untreated. The sand fly Phlebotomus argentipes is the only proven vector of VL in the Southeast Asia region, and VL control in this region has relied on the use of synthetic insecticides for indoor residual spraying (IRS). The use of DDT in VL control programmes has led to the development of resistance to this insecticide in sand flies, resulting in DDT being replaced with the insecticide alpha-cypermethrin.

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International pet travel and commercial operations have increased animal disease importation risks, including for Leishmania infantum, a deadly parasite of humans and domestic dogs. Collaborating as an interdisciplinary working group, we developed an operational tool for veterinary and public health practitioners to assess and manage L. infantum risk in dogs imported to the United States.

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Visceral leishmaniasis derived from Leishmania donovani is transmitted by sand flies (Phlebotomus argentipes) throughout the Indian subcontinent. Although considered anthroponotic, L. donovani infects other mammals susceptible to sand fly bites, including dogs.

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Dogs represent the primary reservoir for Leishmania infantum human visceral leishmaniasis (VL) transmitted through phlebotomine sand flies. Public health initiatives targeting zoonotic VL commonly focus on dogs with severe clinical disease, often in renal failure, as they have previously been considered the most infectious to sand flies. However, more recent studies suggest that dogs with mild to moderate clinical disease may be more infectious than dogs with severe disease.

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The host immune system plays a significant role in managing and clearing pathogen material during an infection, but this complex process presents numerous challenges from a modeling perspective. There are many mathematical and statistical models for these kinds of processes that take into account a wide range of events that happen within the host. In this work, we present a Bayesian joint model of longitudinal and time-to-event data of Leishmania infection that considers the interplay between key drivers of the disease process: pathogen load, antibody level, and disease.

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Motivated by data measuring progression of leishmaniosis in a cohort of US dogs, we develop a Bayesian longitudinal model with autoregressive errors to jointly analyze ordinal and continuous outcomes. Multivariate methods can borrow strength across responses and may produce improved longitudinal forecasts of disease progression over univariate methods. We explore the performance of our proposed model under simulation, and demonstrate that it has improved prediction accuracy over traditional Bayesian hierarchical models.

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Objectives: Resident synovial macrophages (RSM) provide immune sequestration of the joint space and are likely involved in initiation and perpetuation of the joint-specific immune response. We sought to identify RSM in synovial fluid (SF) and demonstrate migratory ability, in additional to functional changes that may perpetuate a chronic inflammatory response within joint spaces.

Methods: We recruited human patients presenting with undifferentiated arthritis in multiple clinical settings.

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Canine leishmaniosis (CanL) is a zoonotic disease caused by protozoan . Dogs with CanL are often coinfected with tick-borne bacterial pathogens, including in the United States. These coinfections have been causally associated with hastened disease progression and mortality.

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The host immune system plays a significant role in managing and clearing pathogen material during an infection, but this complex process presents numerous challenges from a modeling perspective. There are many mathematical and statistical models for these kinds of processes that take into account a wide range of events that happen within the host. In this work, we present a Bayesian joint model of longitudinal and time-to-event data of infection that considers the interplay between key drivers of the disease process: pathogen load, antibody level, and disease.

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Purpose: COVID-19 vaccine uptake remains low for US adolescents and contributes to excess morbidity and mortality. Most research has assessed parental intention to vaccinate their children. We explored differences between vaccine-acceptant and vaccine-hesitant unvaccinated US adolescents using national survey data.

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While many Bayesian state-space models for infectious disease processes focus on population infection dynamics (eg, compartmental models), in this work we examine the evolution of infection processes and the complexities of the immune responses within the host using these techniques. We present a joint Bayesian state-space model to better understand how the immune system contributes to the control of Leishmania infantum infections over the disease course. We use longitudinal molecular diagnostic and clinical data of a cohort of dogs to describe population progression rates and present evidence for important drivers of clinical disease.

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Visceral leishmaniasis (VL) is a vector-borne protozoan disease, which can be fatal if left untreated. Synthetic chemical insecticides are very effective tools for controlling of insect vectors, including the sand fly Phlebotomus argentipes, the vector of VL in the Indian subcontinent. However, repeated use of the same insecticide with increasing doses potentially can create high selection pressure and lead to tolerance and resistance development.

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Visceral leishmaniasis (VL) is a neglected tropical disease that is globally distributed and has the potential to cause very serious illness. Prior literature highlights the emergence and spread of VL is influenced by multiple factors, such as socioeconomic status, sanitation levels or animal and human reservoirs. The study aimed to retrospectively investigate the presence and infectiousness of VL in Rio Grande do Norte (RN), Brazil between 2007 and 2020.

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Background: The Advisory Committee on Immunization Practices (ACIP) recommends shared clinical decision-making (SCDM) regarding HPV vaccination for adults aged 27-45 years who are not adequately vaccinated. The objective of this survey was to understand physician knowledge, attitudes, and practices regarding HPV vaccination in this age group.

Methods: An online survey was administered in June 2021 to physicians who reported practicing internal medicine, family medicine, or obstetrics and gynecology (targeted N = 250 in each practice specialty), selected randomly from potentially eligible physicians from a panel of 2 million U.

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Purpose: Vaccinating adolescents against COVID-19 while avoiding delays in other routine vaccination is paramount to protecting their health. Our objective was to assess parental preferences to have their adolescents aged 12-17 years receive COVID-19 and other routine vaccines at the same time.

Methods: An online survey with a national, quota-based cross-sectional sample of United States parents of youth aged 12-17 years was fielded in April 2021 ahead of FDA's Emergency Use Authorization of COVID-19 vaccine for age 12-15 years.

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Leishmaniasis on the Indian subcontinent is thought to have an anthroponotic transmission cycle. There is no direct evidence that a mammalian host other than humans can be infected with Leishmania donovani and transmit infection to the sand fly vector. The aim of the present study was to evaluate the impact of sand fly feeding on other domestic species and provide clinical evidence regarding possible non-human reservoirs through experimental sand fly feeding on cows, water buffalo goats and rodents.

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Purpose Of Review: Leishmaniasis is a leading cause of parasitic death, with incidence rising from decreased resources to administer insecticide and anti-leishmanial treatments due to the COVID-19 pandemic. Leishmaniasis is nonendemic in the United States (U.S.

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Importance: Children aged 6 months through 4 years have become eligible for COVID-19 vaccination, but little is known about parental intentions regarding, concerns about, or facilitators to COVID-19 vaccination for this age group.

Objectives: To evaluate parental intentions, concerns, and facilitators for COVID-19 vaccination for children aged 6 months through 4 years and to help inform the US Centers for Disease Control and Prevention Advisory Committee on Immunization Practices' deliberations and recommendations for COVID-19 vaccination for children aged 6 months through 4 years.

Design, Setting, And Participants: This cross-sectional study fielded an online survey from February 2 to 10, 2022, among a nonprobability sample of US parents of children aged 6 months through 4 years who were recruited through Qualtrics using quota-based sampling for respondent gender, race and ethnicity, and child age group.

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Influenza typically causes mild infection but can lead to severe outcomes for those with compromised lung health. Flooding, a seasonal problem in Iowa, can expose many Iowans to molds and allergens shown to alter lung inflammation, leading to asthma attacks and decreased viral clearance. Based on this, the hypothesis for this research was that there would be geographically specific positive associations in locations with flooding with influenza diagnosis.

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Vertical transmission of leishmaniasis is common but is difficult to study against the background of pervasive vector transmission. We present genomic data from dogs in the United States infected with Leishmania infantum parasites; these infections have persisted in the apparent absence of vector transmission. We demonstrate that these parasites were introduced from the Old World separately and more recently than L.

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Lyme disease (LD) due to Borrelia burgdorferi is the most prevalent vector-borne disease in the United States. There is a poor understanding of how immunity contributes to bacterial control, pathology, or both during LD. Dogs in an area of endemicity were screened for B.

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This survey study assesses vaccination intentions of unvaccinated US adults in response to full US Food and Drug Administration (FDA) approval of the BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine and any demographic characteristics associated with those intentions.

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