Characterization of the chemosensory protein EforCSP3 and its potential involvement in host location by Encarsia formosa

Chemosensory proteins(CSPs) perform several functions in insects.This study performed the gene expression,ligand-binding,and molecular docking assays on the EforCSP3 identified in the parasitoid wasp Encarsia formosa,to determine whether EforCSP3 functions in olfaction,especially in host location and host preference.The results showed that EforCSP3 was highly expressed in the female head,and its relative expression was much higher in adults than in other developmental stages.The fluorescence binding assays suggested that the EforCSP3 exhibited high binding affinities to a wide range of host-related volatiles,among which dibutyl phthalate,1-octene,β-elemene,and tridecane had the strongest binding affinity with EforCSP3,besides α-humulene and β-myrcene,and should be assessed as potential attractants.Protein structure modeling and molecular docking predicted the amino acid residues of EforCSP3possibly involved in volatile binding.α-Humulene and β-myrcene attracted E.formosa in a previous study and exhibited strong binding affinities with EforCSP3 in the current study.In conclusion,EforCSP3 may be involved in semiochemical reception by E.formosa.

Post-COVID-19 persistent olfactory,gustatory,and trigeminal chemosensory disorders:Definitions,mechanisms,and potential treatments

The nose and the oral cavities are the main sites for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)entry into the body.Smell and taste deficits are the most common acute viral manifestations.Persistent smell disorders are the most common and bothersome complications after SARS-CoV-2 infection,lasting for months to years.The mechanisms and treatment of persistent post-coronavirus disease 2019(COVID-19)smell and taste disorders are still challenges.Information sources for the review are PubMed,Centers for Disease Control and Prevention,Ovid Medline,Embase,Scopus,Web of Science,International Prospective Register of Systematic Reviews,Cumulative Index to Nursing and Allied Health Literature,Elton Bryson Stephens Company,Cochrane Effective Practice and Organization of Care,Cooperation in Science and Technology,International Clinical Trials Registry Platform,World Health Organization,Randomized Controlled Trial Number Registry,and MediFind.This review summarizes the up-to-date information about the prevalence,patterns at onset,and prognoses of post-COVID-19 smell and taste disorders,evidence for the neurotropism of SARS-CoV-2 and the overlap between SARSCoV-1,Middle East respiratory syndrome coronavirus,and SARS-CoV-2 in structure,molecular biology,mode of replication,and host pathogenicity,the suggested cellular and molecular mechanisms for these post-COVID19 chemosensory disorders,and the applied pharmacotherapies and interventions as trials to treat these disorders,and the recommendations for future research to improve understanding of predictors and mechanisms of these disorders.These are crucial for hopeful proper treatment strategies.

Functional Characteristics of a Novel Chemosensory Protein in the Cotton Bollworm Helicoverpa armigera (Hübner)

A chemosensory protein named HarmCSP5 in cotton bollworm Helicoverpa armigera （Hvbner） was obtained from antennal eDNA libraries and expressed in Escherichia coll. The real time quantitative PCR （RT-qPCR） results indicated that HarmCSP5 gene was mainly expressed in male and female antennae but also expressed in female legs and wings. Competitive binding assays were performed to test the binding affinity of recombinant HarmCSP5 to 60 odor molecules including some cotton volatiles. The resules showed that HarmCSP5 showed strong binding abilities to 4-ehtylbenzaldehyde and 3,4-dimethlbenz aldehyde, whereas methyl phenylacetate, 2-decanone, 1-pentanol, carvenol, isobomeol, nerolidol, 2- nonanone and ethyl heptanoate have relatively weak binding affinity. Moreover, the predicted 3D model of HarmCSP5 consists of six α-helices located among residues 33-38 （αl）, 40-48 （α2）, 62-72 （α3）, 80-96 （α4）, 98-108 （α5）, and 116-119 （α6）, two pairs of disulfide bridges Cys49-Cys55, Cys75-Cys78. The two amino acid residues, Ile94 and Trpl01, may play crucial roles in HarmCSP5 binding with ligands and need further study for confirmation.

Molecular and in vitro biochemical assessment of chemosensory protein 10 from brown planthopper Nilaparvata lugens at acidic pH

Chemosensory proteins(CSPs)are important molecular components of the insect olfactory system,which are involved in capturing,binding,and transporting hydrophobic odour molecules across the sensillum in sensillar lymph in regulating insect behavior.This protein family(CSPs)is also involved in many other systems that are not linked to olfactory receptors in olfactory sensilla.The brown planthopper(BPH)is a monophagous pest of rice that causes damage by sucking phloem sap and transmitting a number of diseases caused by viruses.In this study,fluorescence competitive binding assay and fluorescence quenching assay at acidic p H were performed as well as homology modelling to describe the binding affinity of Nlug CSP10.Fluorescence competitive binding assay(FCBA)demonstrated that Nlug CSP10 bound strongly to nonadecane,farnesene,and 2-tridecanone at acidic p H.The results of FCBA indicated that Nlug CSP10 bound different ligands at the physiological p H(5.0)of the bulk sensillum lymph.Fluorescence quenching assay demonstrated that Nlug CSP10 generated a stable complex with 2-tridecanone,while two ligands nonadecane and farnesene collided due to molecular collisions.The interaction of selected ligands with the modelled structure of Nlug CSP10 was also analyzed,which found the key amino acids(Gln23,Gln24,Gln25,Asn27,Met33,Ser34,Ile35,Tyr36,Asn42,Met43,Val45,Asn46,Asn93,Arg96,Ala97,Lys99,and Ala100)in Nlug CSP10 that were involved in binding of volatile compounds.The present study contributes to the binding profile of Nlug CSP10 that promotes the development of behaviorally active ligands based on BPH olfactory system.

Effect of drug therapies on self-reported chemosensory outcomes after COVID-19

Objective:The aim of this study was to assess the relative efficacy of medications used following severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection on self-reported alterations in taste and/or smell function.Methods:Seven hundred and fourteen persons with self-reported postcoronavirus disease 2019(post-COVID-19)chemosensory disorders were personally interviewed regarding specific medications they were administered following the acute phase of the disease.The dependent measure—self-reported total recovery of chemosensory symptoms—was subjected to stepwise logistic regression.Independent predictors included demographic and clinical variables,in addition to specific medications used to mitigate disease symptoms(i.e.,systemic corticosteroids,oseltamivir,vitamin C,ibuprofen,hydroxychloroquine,azithromycin,ivermectin,nitazoxanide,anticoagulants,and zinc).Results:The median time between COVID-19 symptom onset and the interviews was 81 days(interquartile range:60-104).Of the 714 subjects,249(34.9%)reported total recovery of their chemosensory function;437(61.2%)had at least one treatment since the beginning of the disease.Women and those with more comorbidities had undergone more treatments.The recovery rates of the treated and nontreated groups did not differ significantly.Nonetheless,respondents who had used nitazoxanide tended to have a higher rate of self-reported taste or smell recovery.Those who took oral zinc were less likely to improve.Conclusions:No medication employed during the first months after SARS-CoV-2 infection had a clear positive effect on returning self-reported smell or taste function to normal,although nitrazoxide trended in a positive direction.Oral zinc had a negative effect on the reported recovery of these senses.

The role of chemosensory protein 10 in the detection of behaviorally active compounds in brown planthopper, Nilaparvata lugens

Chemosensory proteins(CSPs)play important roles in insects’chemoreception,although their specific functional roles have not been fully elucidated.In this study,we conducted the developmental expression patterns and competitive binding assay as well as knock‐down assay by RNA interference both in vitro and in vivo to reveal the function of NlugCSP10 from the brown planthopper(BPH),Nilaparvata lugens(Stål),a major pest in rice plants.The results showed that NlugCSP10 messenger RNA was significantly higher in males than in females and correlated to gender,development and wing forms.The fluorescence binding assays revealed that NlugCSP10 exhibited the highest binding affinity with cis‐3‐hexenyl acetate,eicosane,and(+)‐β‐pinene.Behavioral assay revealed that eicosane displayed attractant activity,while cis‐3‐hexenyl acetate,similar to(+)‐β‐pinene significantly repelled N.lugens adults.Silencing of NlugCSP10,which is responsible for cis‐3‐hexenyl acetate binding,significantly disrupted cis‐3‐hexenyl acetate communication.Overall,findings of the present study showed that NlugCSP10 could selectively interrelate with numerous volatiles emitted from host plants and these ligands could be designated to develop slow‐release mediators that attract/repel N.lugens and subsequently improve the exploration of plans to control this insect pest.

Bioinformatics-Based Identification of Chemosensory Proteins in African Malaria Mosquito, Anopheles gambiae

Chemosensory proteins (CSPs) are identifiable by four spatially conserved Cys-teine residues in their primary structure or by two disulfide bridges in their tertiary structure according to the previously identified olfactory specific-D related proteins. A genomics- and bioinformatics-based approach is taken in the present study to identify the putative CSPs in the malaria-carrying mosquito, Anopheles gambiae. The results show that five out of the nine annotated candidates are the most possible Anopheles CSPs of A. gambiae. This study lays the foundation for further functional identification of Anopheles CSPs, though all of these candidates need additional experimental verification.

Molecular cloning and comparative analysis of transcripts encoding chemosensory proteins from two plant bugs, Lygus lineolaris and Lygus hesperus

Chemosensory proteins(CSPs)are soluble carrier proteins typically characterized by a six‐helix bundle structure joined by two disulfide bridges and a conserved Cys spacing pattern(C1‐X6‐8‐C2‐X16‐21‐C3‐X2‐C4).CSPs are functionally diverse with reported roles in chemosensation,immunity,development,and resistance.To expand our molecular understanding of CSP function in plant bugs,we used recently developed transcriptomic resources for Lygus lineolaris and Lygus hesperus to identify 17 and 14 CSP‐like sequences,respectively.The Lygus CSPs are orthologous and share significant sequence identity with previously annotated CSPs.Three of the CSPs are predicted to deviate from the typical CSP structure with either five or seven helical segments rather than six.The seven helix CSP is further differentiated by an atypical C3‐X3‐C4 Cys spacing motif.Reverse transcriptase PCR‐based profiling of CSP transcript abundance in adult L.lineolaris tissues revealed broad expression for most of the CSPs with antenna specific expression limited to a subset of the CSPs.Comparative sequence analyses and homology modeling suggest that variations in the amino acids that comprise the Lygus CSP binding pockets affect the size and nature of the ligands accommodated.

Chromosome-level genome assembly of Cylas formicarius provides insights into its adaptation and invasion mechanisms

Cylasformicarius is one of the most important pests of sweet potato worldwide, causing considerable ecological and economic damage.This study improved the effect of comprehensive management and understanding of genetic mechanisms by examining the functional genomics of C. formicarius.Using Illumina and PacBio sequencing, this study obtained a chromosome-level genome assembly of adult weevils from lines inbred for 15 generations.The high-quality assembly obtained was 338.84 Mb, with contig and scaffold N50 values of 14.97 and 34.23 Mb, respectively.In total, 157.51 Mb of repeat sequences and 11 907 protein-coding genes were predicted.A total of 337.06 Mb of genomic sequences was located on the 11 chromosomes, accounting for 99.03%of the total length of the associated chromosome.Comparative genomic analysis showed that C. formicarius was sister to Dendroctonus ponderosae, and C. formicarius diverged from D. ponderosae approximately 138.89 million years ago (Mya).Many important gene families expanded in the C. formicarius genome were involved in the detoxification of pesticides, tolerance to cold stress and chemosensory system.To further study the role of odorant-binding proteins (OBPs) in olfactory recognition of C. formicarius, the binding assay results indicated that Cfor OBP4–6 had strong binding affinities for sex pheromones and other ligands.The high-quality C. formicarius genome provides a valuable resource to reveal the molecular ecological basis, genetic mechanism, and evolutionary process of major agricultural pests;it also offers new ideas and new technologies for ecologically sustainable pest control.

A conserved odorant receptor identified from antennal transcriptome of Megoura crassicauda that specifically responds to cis-jasmone

Herbivore-induced plant volatiles(HIPVs)play a key role in the interactions between plants and herbivorous insects,as HIPVs can promote or deter herbivorous insects’behavior.While aphids are common and serious phloem-feeding pests in farmland ecosystems,little is known about how aphids use their sensitive olfactory system to detect HIPVs.In this study,the antennal transcriptomes of the aphid species Megoura crassicauda were sequenced,and expression level analyses of M.crassicauda odorant receptors(ORs)were carried out.To investigate the chemoreception mechanisms that M.crassicauda uses to detect HIPVs,we performed in vitro functional studies of the ORs using 11 HIPVs reported to be released by aphid-infested plants.In total,54 candidate chemosensory genes were identified,among which 20 genes were ORs.McraOR20 and McraOR43 were selected for further functional characterization because their homologs in aphids were quite conserved and their expression levels in antennae of M.crassicauda were relatively high.The results showed that McraOR20 specifically detected cis-jasmone,as did its ortholog ApisOR20 from the pea aphid Acyrthosiphon pisum,while McraOR43 did not respond to any of the HIPV chemicals that were tested.This study characterized the ability of the homologous OR20 receptors in the two aphid species to detect HIPV cis-jasmone,and provides a candidate olfactory target for mediating aphid behaviors.

Differential expression of pancreatic protein and chemosensing receptor m RNAs in NKCC1-null intestine

AIM: To investigate the intestinal functions of the NKCC1 Na^+-K^+-2Cl cotransporter(SLC12a2 gene), differential m RNA expression changes in NKCC1-null intestine were analyzed.METHODS: Microarray analysis of m RNA from intestines of adult wild-type mice and gene-targeted NKCC1-null mice(n = 6 of each genotype) was performed to identify patterns of differential gene expression changes. Differential expression patterns were further examined by Gene Ontology analysis using the online Gorilla program, and expression changes of selected genes were verified using northern blot analysis and quantitative real time-polymerase chain reaction. Histological staining and immunofluorescence were performed to identify cell types in which upregulated pancreatic digestive enzymes were expressed.RESULTS: Genes typically associated with pancreatic function were upregulated. These included lipase, amylase, elastase, and serine proteases indicative of pancreatic exocrine function, as well as insulin and regenerating islet genes, representative of endocrine function. Northern blot analysis and immunohistochemistry showed that differential expression of exocrine pancreas m RNAs was specific to the duodenum and localized to a subset of goblet cells. In addition, a major pattern of changes involving differential expression of olfactory receptors that function in chemical sensing, as well as other chemosensing G-protein coupled receptors, was observed. These changes in chemosensory receptor expression may be related to the failure of intestinal function and dependency on parenteral nutrition observed in humans with SLC12a2 mutations. CONCLUSION: The results suggest that loss of NKCC1 affects not only secretion, but also goblet cell function and chemosensing of intestinal contents via G-protein coupled chemosensory receptors.

Comparison of trigeminal lateralization with differing stimulants

Trigeminal-specific stimulants have been shown to activate different receptors preferentially and this likely accounts for variation in sensory perception.It is unclear whether trigeminal sensitivity is similar across different transient receptor potential(TRP)receptors or if dysfunction of different receptors results in differing patient symptoms.Therefore,a prospective cohort study was conducted,consisting of trigeminal lateralization testing with three different stimulants(eucalyptol,isothiocyanate,acetic acid),olfaction testing with Sniffin'Sticks,and measurement of various patient‐reported outcome measures(PROMs).A total of 50 participants were enrolled across the olfactory spectrum.Mean TDI score was 27.1±8.3(range 7.0–39.5)with 38%normosmic and 62%dysosmic.Mean trigeminal lateralization scores out of 20 in the overall cohort were 16.18(2.78)for eucalyptol,14.94(3.49)for mustard oil,and 15.28(3.68)for vinegar.Eucalyptol showed a significant correlation with threshold scores of Sniffin'Sticks.A significant correlation was found between acetic acid and various PROMs.None of the lateralization scores of the trigeminal stimulants correlated to each other significantly and there was no correlation to age.The lack of correlation suggests that the measured sensitivity of one type of TRP receptor may not translate to similar sensitivity of the other receptors.Additional investigations with TRPV1 and TRPA1 agonists are needed to corroborate our findings.

Clinical studies in COVID-related olfactory disorders:Review of an institutional experience

Objective:To share a single institutional experience with clinical research on COVID-related olfactory dysfunction(OD).Data Source/Method:Narrative review of published original data and ongoing clinical trials on COVID-related OD at Washington University from 2020 to 2023.Results:There were three new diagnostic-/patient-reported outcome measures developed and tested.We report five clinical trials of interventions for COVID-related olfactory disorders:combined Visual-Olfactory Training(VOLT)with patient-preferred scents versus standard olfactory training(VOLT trial),oral gabapentin versus placebo(Gabapentin for the Relief of Acquired Chemosensory Experience trial),nasal theophylline irrigations versus placebo(Smell Changes and Efficacy of Nasal Theophylline trial),stellate ganglion block(single-arm),and mindfulness-based stress reduction(MBSR)versus lifestyle intervention(MBSR trial).Conclusions:Initial intervention trials for COVID-related OD have shown potential for improving subjective and objective olfactory outcomes.However,there remains no gold standard treatment that definitively outperforms placebo in controlled trials.Therefore,continued investigation of novel therapeutic strategies for COVID-related OD is necessary to maximize olfactory outcomes for affected patients.

Increased expression of CSP and CYP genes in adult silkworm females exposed to avermectins

We analyzed 20 chemosensory protein （CSP） genes of the silkworm Bombyx mori. We found a high number of retrotransposons inserted in introns. We then analyzed expression of the 20 BrnorCSP genes across tissues using quantitative real-time polymerase chain reaction （PCR）. Relatively low expression levels of BmorCSPs were found in the gut and fat body tissues. We thus tested the effects of endectocyte insecticide abamectin （B 1 a and Blb avermectins） on BmorCSP gene expression. Quantitative real-time PCR experi- ments showed that a single brief exposure to insecticide abamectin increased dramatically CSP expression not only in the antennae but in most tissues, including gut and fat body. Furthermore, our study showed coordinate expression of CSPs and metabolic cytochrome P450 enzymes in a tissue-dependent manner in response to the insecticide. The function of CSPs remains unknown. Based on our results, we suggest a role in detecting xenobiotics that are then detoxified by cytochrome P450 anti-xenobiotic enzymes.

Molecular and evolutionary analyses of formyl peptide receptors suggest the absence of VNO-specific FPRs in primates

Formyl peptide receptors (FPRs) were observed to expand in rodents and were recently suggested as candidate vomeronasal chemo-sensory receptors. Since vomeronasal chemosensory receptors usually underwent positive selection and evolved concordantly with the vomeronasal organ (VNO) morphology, we surveyed FPRs in primates in which VNO morphology is greatly diverse and thus it would provide us a clearer view of VNO-FPRs evolution. By screening available primate genome sequences, we obtained the FPR repertoires in representative primate species. As a result, we did not find FPR family size expansion in primates. Further analyses showed no evolution-ary force variance between primates with or without VNO structure, which indicated that there was no functional divergence among pri-mates FPRs. Our results suggest that primates lack the VNO-specific FPRs and the FPR expansion is not a common phenomenon in mammals outside rodent lineage, regardless of VNO complexity.

Influence of medications on taste and smell

Medications frequently have chemosensory side effects that can adversely affect compliance with medical treatment regimens. Hundreds of drugs have been reported to induce unpleasant tastes and/or odors as well as altered chemosensations when administered alone or in combination with other medications. Some chemosensory complaints are due to the sensory properties of the drug itself such as aversive bitter and metallic tastes. However, most chemo-sensory side effects of drugs are due to alterations in the transduction pathways, biochemical targets, enzymes, and transporters by the offending medications. Studies of chemosensory perception in medicated older individuals have found that taste and smell loss is greatest for those consuming the largest number of prescription drugs. There are no standard treat-ments for drug-induced chemosensory disorders because each drug has unique biological ef-fects. However, there are a few treatment options to ameliorate chemosensory alterations including addition of simulated flavors to food to compensate for losses and to override offend-ing tastes and smells.

Genomes of 12 fig wasps provide insights into the adaptation of pollinators to fig syconia

Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism.The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes.However,there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators.In fig syconia,there are also non-pollinator species.The non-pollinator species differ in their evolutionary and life histories from pollinators.We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome.The pollinators colonized the figs approximately 66.9 million years ago,consistent with the origin of host figs.Compared with nonpollinators,many more genes in pollinators were subject to relaxed selection.Seven genes were absent in pollinators in response to environmental stress and immune activation.Pollinators had more streamlined gene repertoires in the innate immune system,chemosensory toolbox,and detoxification system.Our results provide genomic evidence for the differentiation between pollinators and nonpollinators.The data suggest that owing to the long-term adaptation to the fig,some genes related to functions no longer required are absent in pollinators.

The role of bitter and sweet taste receptors in upper airway innate immunity: Recent advances and future directions

Bitter(T2R)and sweet(T1R)taste receptors have been implicated in sinonasal innate immunity and in the pathophysiology of chronic rhinosinusitis(CRS).Taste receptors are expressed on several sinonasal cell types including ciliated epithelial cells and solitary chemosensory cells.Bitter agonists released by pathogenic microbes elicit a T2R dependent signaling cascade which induces the release of bactericidal nitric oxide,increases mucociliary clearance,and promotes secretion of antimicrobial peptides.Genetic variation conferred by polymorphisms in T2R related genes is associated with differential CRS susceptibility,symptomatology and post-treatment outcomes.More recently,based on our understanding of T1R and T2R function,investigators have discovered novel potential therapeutics in T2R agonists and T1R antagonists.This review will discuss bitter and sweet taste receptor function in sinonasal immunity,explore the emerging diagnostic and therapeutic implications stemming from the most recent findings,and suggest directions for future research.

A small number of male-biased candidate pheromone receptors are expressed in large subsets of the olfactory sensory neurons in the antennae of drones from the European honey bee Apis mellifera

In the European honey bee(Apis mellifera),the olfactory system is essential for foraging and intraspecific communication via pheromones.Honey bees are equipped with a large repertoire of olfactory receptors belonging to the insect odorant receptor(OR)family.Previous studies have indicated that the transcription level of a few OR types including OR11,a receptor activated by the queen-released pheromone compound(2£)-9-oxodecenoic acid(9-ODA),is significantly higher in the antenna of males(drones)than in female workers.However,the number and distribution of antennal cells expressing male-biased ORs is elusive.Here,we analyzed antennal sections from bees by in situ hybridization for the expression of the male-biased receptors OR11,OR18,and OR170.Our results demonstrate that these receptors are expressed in only moderate numbers of cells in the antennae of females(workers and queens),whereas substantially higher cell numbers express these ORs in drones.Thus,the reported male-biased transcript levels are due to sex-specific differences in the number of antennal cells expressing these receptors.Detailed analyses for OR11 and OR18 in drone antennae revealed expression in two distinct subsets of olfactory sensory neurons(OSNs)that in total account for approximately 69%of the OR-positive cells.Such high percentages of OSNs expressing given receptors are reminiscent of male-biased ORs in moths that mediate the detection of female-released sex pheromone components.Collectively,our findings indicate remarkable similarities between male antennae of bees and moths and support the concept that male-biased ORs in bee drones serve the detection of female-emitted sex pheromones.

Objective screening for olfactory and gustatory dysfunction during the COVID-19 pandemic: A prospective study in healthcare workers using self-administered testing

Background: Smell and taste loss are highly prevalent symptoms in coronavirus disease 2019 (COVID-19), although few studies have employed objective measures to quantify these symptoms, especially dysgeusia. Reports of unrecognized anosmia in COVID-19 patients suggests that self-reported measures are insufficient for capturing patients with chemosensory dysfunction.Objectives: The purpose of this study was to quantify the impact of recent COVID-19 infection on chemosensory function and demonstrate the use of at-home objective smell and taste testing in an at-risk population of healthcare workers.Methods: Two hundred and fifty healthcare workers were screened for possible loss of smell and taste using online surveys. Self-administered smell and taste tests were mailed to respondents meeting criteria for elevated risk of infection, and one-month follow-up surveys were completed.Results: Among subjects with prior SARS-CoV-2 infection, 73% reported symptoms of olfactory and/or gustatory dysfunction. Self-reported smell and taste loss were both strong predictors of COVID-19 positivity. Subjects with evidence of recent SARS-CoV-2 infection (<45 days) had significantly lower olfactory scores but equivalent gustatory scores compared to other subjects. There was a time-dependent increase in smell scores but not in taste scores among subjects with prior infection and chemosensory symptoms. The overall infection rate was 4.4%, with 2.5% reported by PCR swab.Conclusion: Healthcare workers with recent SARS-CoV-2 infection had reduced olfaction and normal gustation on self-administered objective testing compared to those without infection. Rates of infection and chemosensory symptoms in our cohort of healthcare workers reflect those of the general public.