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Rooney, J.

Publications and source records attributed to Rooney, J..

3 recordsLinked to original sources

One Health Investigation of SARS-CoV-2 Infection and Seropositivity among Pets in Households with Confirmed Human COVID-19 Cases - Utah and Wisconsin, 2020

BackgroundApproximately 67% of U.S. households have pets. Limited data are available on SARS-CoV-2 in pets. We assessed SARS-CoV-2 infection in pet cohabitants as a sub-study of an ongoing COVID-19 household transmission investigation. MethodsMammalian pets from households with [≥]1 person with laboratory-confirmed COVID-19 were eligible for inclusion from April-May 2020. Demographic/exposure information, oropharyngeal, nasal, rectal, and fur swabs, feces, and blood were collected from enrolled pets and tested by rRT-PCR and virus neutralization assays. FindingsWe enrolled 37 dogs and 19 cats from 34 of 41 eligible households. All oropharyngeal, nasal, and rectal swabs tested negative by rRT-PCR; one dogs fur swabs (2%) tested positive by rRT-PCR at the first animal sampling. Among 47 pets with serological results from 30 households, eight (17%) pets (4 dogs, 4 cats) from 6 (20%) households had detectable SARS-CoV-2 neutralizing antibodies. In households with a seropositive pet, the proportion of people with laboratory-confirmed COVID-19 was greater (median 79%; range: 40-100%) compared to households with no seropositive pet (median 37%; range: 13-100%) (p=0.01). Thirty-three pets with serologic results had frequent daily contact ([≥]1 hour) with the human index patient before the persons COVID-19 diagnosis. Of these 33 pets, 14 (42%) had decreased contact with the human index patient after diagnosis and none (0%) were seropositive; of the 19 (58%) pets with continued contact, 4 (21%) were seropositive. InterpretationsSeropositive pets likely acquired infection from humans, which may occur more frequently than previously recognized. People with COVID-19 should restrict contact with animals. FundingCenters for Disease Control and Prevention, U.S. Department of Agriculture

microbiology

Evolutionary loss of inflammasomes in carnivores to facilitate carriage of zoonotic infections

Zoonotic infections, such as COVID-19, reside in animal hosts before jumping species to humans. The Carnivora, like mink, carry many zoonoses yet how diversity in host immune genes across species impact upon pathogen carriage are poorly understood. Here we describe a progressive evolutionary downregulation of pathogen sensing inflammasome pathways in Carnivora. This includes the loss of nucleotide-oligomerisation domain leucine rich repeat receptors (NLRs), acquisition of a unique caspase-1/-4 effector fusion protein that processes gasdermin D pore formation without inducing lytic cell death and the formation of an NLRP3-caspase-8 containing inflammasome that inefficiently processes interleukin-1{beta} (IL-1{beta}). Inflammasomes regulate gut immunity, but the carnivorous diet is antimicrobial suggesting a tolerance to the loss of these immune pathways. The consequences of systemic inflammasome downregulation, however, can reduce the host sensing of specific pathogens such that they can reside undetected in the Carnivora.

immunology

Hedgehog signalling regulates patterning of the murine and human dentitions through Gas1 co-receptor function

The mammalian dentition exhibits wide numerical and morphological variation between different species. The regulation of dental pattern is achieved through complex reiterative molecular signalling interactions that occur through multiple stages of tooth development. We show that mice with loss-of-function in the Hedgehog co-receptor Gas1 have variation in size, morphology and number of teeth within the molar dentition. Specifically, premolar-like supernumerary teeth are present with high penetrance, arising through survival and continued development of vestigial tooth germs. We further demonstrate that Gas1 function in cranial neural crest cells is essential for the regulation of tooth number, acting to restrict Wnt signalling in vestigial tooth germs through facilitation of Shh signalling. Moreover, regulation of tooth number is independent of the additional Hedgehog co-receptors Cdon and Boc. Interestingly, further reduction of Shh pathway activity in a Gas1 mutant background leads to fusion of the molar field and ultimately, developmental arrest of tooth development rather than exacerbating the supernumerary phenotype. Finally, we demonstrate defective coronal morphology in the molar dentition of human subjects carrying GAS1 missense mutations, suggesting that regulation of Hedgehog signalling through GAS1 is also essential for normal patterning of the human dentition.

developmental biology