Negative Serological Tests Research Articles

Immunological, Clinical, and Epidemiological Features of Guillain-Barré Syndrome Associated with SARS-CoV-2 Infection

Objectives. There is a growing interest in understanding the association between Guillain-Barré syndrome (GBS) and SARS-CoV-2 infection. The aim of this study was to analyse various characteristics of GBS before and after the pandemic outbreak and thus identify possible distinctive features of GBS associated with SARS-CoV-2 (GBS-S). Material and Methods. In our centre, we retrospectively reviewed the records of patients diagnosed with GBS between January 2018 and March 2022. Epidemiological, clinical, and immunological data were analysed and compared between patients with GBS according to the time of diagnosis and antecedent events. Results. Thirty-nine patients with GBS were included: nine (23.1%) were diagnosed with GBS-S. GBS-S was most frequent in 2020 (6/13, 46.1%). Most of these patients developed a postinfectious classic demyelinating variant (4/9, 44.4%) with frequent bilateral facial paralysis (4/9, 44.4%). Serum antiganglioside antibodies (AGAs) were found in 1/9 patients with GBS-S. Serum anti-SSA/Ro60 antibodies were highly prevalent in GBS-S (7/9 (77.8%) vs. 3/11 (27.3%), p = 0.019 ). Three cases associated with SARS-CoV-2 vaccination (GBS-V) were detected. Of note, two had bilateral facial paralysis and anti-SSA/Ro60 antibodies. Conclusion. Our findings suggest that SARS-CoV-2 has become an important antecedent event associated with GBS in our setting. GBS-S shows a postinfectious demyelinating immune-mediated profile with negative serological testing for AGAs. Serum anti-SSA/Ro60 antibodies were found frequently in these patients. Bilateral facial paralysis stands out as a possible characteristic clinical feature both in GBS-S and GBS-V. Larger, prospective studies are needed for a better understanding of its immunopathogenesis.

EVALUATION OF THE EFFICIENCY OF THE SEROLOGICAL HAI METHOD FOR THE DETECTION OF ANTIBODIES TO THE EGG DROP SYNDROME VIRUS

The article describes the features of the course of the disease of laying hens with Egg drop syndrome (EDS). This is a contagious viral disease of commercial and breeding laying hens, which is characterized by damage to the reproductive organs, a sharp decrease in laying capacity, changes in the pigmentation and shape of laid eggs, the appearance of effusions, thinning, deformations, and in some places the complete absence of a shell, a decrease in the percentage of hatching of chickens from hatching eggs and a deterioration in their viability. Morbidity is 10–70 %, mortality is 1–10 %. The disease in chickens occurs during the egg-laying period, until then no clinical signs of infection are observed. Three forms of EDS have been described: classic, endemic, and sporadic. The diagnosis of EDS is established on the basis of the results of laboratory tests, taking into account epizootological data, clinical signs and pathological anatomical changes. At the same time, special attention is paid to the decrease in egg production and the appearance of deformed and shelles eggs in clinically healthy chickens, the death of embryos and day-old chicks. Laboratory diagnostics is based on express, virological and retrospective methods. One of the most common methods of diagnosing EDS is retrospective diagnosis, which consists in detecting a diagnostic (minimum 4-fold) increase in the antibody titer in paired blood sera of chickens by the methods of HAI, IHA or ELISA. HAI is recommended for mass serological examinations of poultry farms. The detection of Anti-Hemagglutinin Antibody (Anti-HA) in the studied blood sera at a titer of 1:16 (4 log2) and higher in farms where specific prevention of EDS is not carried out indicates the circulation of the field strain of EDS virus among poultry. It should be noted that chickens that do not yet lay deformed eggs can be infected with the virus, but do not give a humoral immune response to latent infection. Thus, in flocks of chickens that were infected transovarially, antibodies are not synthesized during the breeding period. A negative serological test in chickens under the age of 20 weeks does not guarantee the absence of EDS infection. Differential diagnosis requires the exclusion of infectious bronchitis, infectious laryngotracheitis, Newcastle disease and respiratory mycoplasmosis. An analysis of 20 inactivated vaccines from various manufacturing companies registered in Ukraine for the specific prevention of EDS was carried out, including monovalent – 3 and associated, namely 3-component – 10 and 4-component – 7. During serological monitoring, it was established, that the average titers in the sera of laying hens to the EDS virus from batches of different ages due to different terms after vaccination with inactivated vaccines ranged from 7.0 log2 to 13.2 log2. The average titers to the EDS virus above the basic norm were 16 % among birds of 4-8 batches (280, 310 and 460 days). It was established that the percentage of protective antibodies to the EDS virus in 25 batches of laying hens ranged from 78 to 100. The use of inactivated vaccines against EDS stimulates the formation of an active immune response in laying hens in 84 % of the studied batches. Carrying out constant monitoring of the effectiveness of inactivated vaccines against by means of serological monitoring of blood sera from birds in the HAI will allow, depending on the epizootic situation, to timely adjust the vaccination scheme and ensure stable economic indicators in commercial and breeding flocks of laying hens.

PP102 Selecting The Sequence Of Diagnostic Tests For Leprosy In Brazil

IntroductionHansen’s disease, or leprosy, is a chronic bacterial infection that affects the nerves, skin, eyes, and nose lining. In 2019, there were 202,256 new cases reported globally, and nearly 28,000 new cases are diagnosed each year in Brazil. The best way to prevent the spread of Hansen’s disease is early diagnosis and treatment of infected individuals. Most diagnoses are done clinically, but only the microscopic analysis of slit-skin smears is funded in Brazil. Serologic and polymerase chain reaction (PCR) tests have also been developed to aid in the diagnosis. The goal of this study was to identify the most cost-effective strategy for increasing the diagnosis of Hansen’s disease in Brazil.MethodsWe examined the impact of the following four strategies using a decision tree model: (i) slit-skin smear only; (ii) PCR test only; (iii) serologic testing followed by slit-skin smear for positive samples; and (iv) serologic testing followed by slit-skin smear for positive samples and PCR test for negative serologic tests and negative slit-skin smears. The accuracy of the tests was determined using a systematic review and meta-analysis and validated by experts. The costs were calculated from the Brazilian health system perspective. Univariate and probabilistic analyses were also conducted.ResultsSerologic testing or PCR followed by slit-skin smear was dominated in the economic model (more false-negative samples and more costly). The addition of serologic testing and PCR to the diagnostic sequence made the strategy more expensive than slit-skin smears alone, but it significantly reduced the percentage of false negative results (from 7.3 to 2.9%) at an estimated cost of USD 533.61 per incremental diagnosis. Disease prevalence was the most important variable in the sensitivity analysis.ConclusionsThis is the first cost-effectiveness model undertaken for Hansen’s disease. The results indicate that incorporating serology and PCR testing into the Brazilian health system could be an appealing option for reducing the spread of Hansen’s disease in Brazil.

Hemophagocytic Lymphohystiocytosis in a Patient with Post-Acute COVID-19 Infection

Introduction: Hemophagocytic lymphohistiocytosis [HLH] is characterized by immune dysregulation with extensive inflammation and tissue destruction due to abnormal immune activation. Although primary HLH is commoner in the pediatric population, secondary HLH [sHLH] is more typical in adults, with underlying associations such as hematologic malignancy, infections or rheumatologic conditions. COVID-19 infection has been associated with immune dysregulation syndromes such as cytokine storm as well as HLH. However, post COVID-19 patients who have recovered with negative serologic tests may also present with sHLH, an unusual finding which our case demonstrates. Case report: A 73-year-old male with a notable past medical history of fall COVID-19 infection approximately 11 months prior presented initially to emergency services with a chief complaint of high fevers, lethargy and progressive changes in mentation gradually progressive over the last 5 months duration. Initial work-up for sources of infection including testing for atypical infections and imaging investigations were unrevealing. Laboratory investigations were remarkable initially for transaminitis, elevated LDH, anemia and thrombocytopenia. Coagulation panel revealed prolonged APTT and PT with low fibrinogen. Ferritin level was markedly elevated. This presentation was concerning for hemophagocytic lymphohistiocytosis. The patient did have a bone marrow biopsy two months prior to presentation which was unremarkable for hematologic malignancy or features suggestive of HLH such as hemophagocytosis. In view of the patient's high H score and clinical suspicion for HLH, he was initiated on dexamethasone 20 mg daily. Cryoprecipitate and platelet transfusions were administered for correction of coagulopathy. Over the course of the hospitalization, WBC count continued to drop with critically low absolute neutrophil counts prompting initiation of Filgrastim. No noticeable clinical improvement was noted over the subsequent days of hospitalization, and the patient was subsequently trialed on an intravenous immunoglobulin protocol for 3 days. Despite all treatment offered, the patient continued to deteriorate and after consultation with family members and the palliative care team, patient was transitioned to comfort measures only and code status was changed to DNR/DNI. The patient subsequently passed away a few days later. Conclusion: sHLH following COVID-19 infection, although previously described, remains a poorly understood phenomenon. Even more puzzling is why certain patients develop a delayed sHLH following postacute COVID-19 illness. Notably, the severity of the COVID-19 infection does not appear to be related to one's predisposition to develop sHLH. Regardless of etiology, the mortality of HLH remains high even with appropriate therapy, especially with neurologic involvement and markedly elevated ferritin levels.

EFFECT OF OMALIZUMAB ON VENOM SPECIFIC IGE AND VENOM SKIN TESTING

<h3>Introduction</h3> Omalizumab, a monoclonal IgG antibody which binds free IgE, is indicated for the treatment of chronic spontaneous urticaria, uncontrolled nasal polyps, and moderate to severe asthma with perennial allergic sensitization. This case illustrates the effect of omalizumab on venom-specific IgE and percutaneous testing. <h3>Case Description</h3> A 48 year old female with severe persistent asthma on omalizumab for six years experienced wheezing and throat swelling within two hours of a suspected hymenoptera sting. Evaluation while patient remained on omalizumab included venom serology obtained two weeks after sting, which was positive only to paper wasp and white-faced hornet, and percutaneous testing three months after sting to honeybee, yellow jacket, and yellow hornet, which was negative through 0.1 ug/mL intradermals, at which time testing was stopped due to systemic reaction. After holding omalizumab for sixteen weeks, repeat percutaneous testing was performed but confounded by dermatographism; repeat venom serology revealed increased specific IgE to all tested hymenoptera except honeybee. <h3>Discussion</h3> To our knowledge, this is the first report describing omalizumab's effect on venom-specific IgE levels and percutaneous testing. Given previous studies that have suggested omalizumab does not convert specific IgE for environmental allergens from positive to negative, it is important for allergists to be aware of omalizumab's potential to suppress venom-specific IgE and skin test reactivity. If a patient on omalizumab with concern for venom hypersensitivity has negative serologic or percutaneous testing to hymenoptera, consideration should be given to repeating testing after omalizumab has been discontinued for four to five half-lives.

57-Year-Old Man With Headache, Vomiting, and Gait Instability

57-Year-Old Man With Headache, Vomiting, and Gait Instability

Prevalence and Relationship between Helicobacter pylori infection and Obesity in the Kurdish population

Background: Globally obesity is a commonly health condition. A great number of investigators have been studying the association between Helicobacter pylori (H. pylori) infection and obesity. It’s also known that H. pylori causes inflammation within the mucosa of the stomach which is known as gastritis. However, due to the arguable data in the literature, the relationship between H. Pylori and obesity remains debatable and there is no comprehensive proof for the association.&#x0D; Objective: To study the Prevalence and Relationship between Helicobacter pylori infection and Obesity.&#x0D; Methods: In this study 200 subjects were contributed, including 100 patients positive tested with H.pylori and 100 healthy participants with negative serological test for H. pylori infection. The data were collected in different places in the Kurdistan region of Iraq including Rizgary Hospital in Erbil and Alaa laboratory in Soran city and other places around Erbil Provence. The body mass index was calculated by measuring the weight in kg and length of participants in cm. Furthermore, all subjects filled in a self-administered questionnaire to collect more detailed data about the subjects. Descriptive and inferential statistics were obtained using statistical analysis programs including SPSS and GraphPad prism.&#x0D; Results: The prevalence of obesity is significantly higher in Helicobacter pylori-positive patients compared to the control in young age persons, and the result showed also that H. pylori positive group are consuming significantly more fast food and have a higher BMI compared to control group.&#x0D; Conclusion: Our result significantly indicates an association between H. Pylori infection and overweight/obesity examined in the case-control study in the Kurdish population.

The Serological Examination of Immunoglobulin A Anti-Early Antigen of Epstein–Barr Virus (Anti-EA EBV IgA) in the Nias Tribe Nasopharyngeal Cancer Patients

BACKGROUND: Nasopharyngeal cancer (NPC) is a health problem associated with malignancies of the ear, nose, and throat. The main pathogenesis of NPC is Epstein–Barr virus (EBV) infection. The signs and symptoms of NPC are non-specific, causing the occurrence of delay in diagnosis leading to treatment failure. The early detection based on the NPC profile using immunoglobulin A (IgA) antibodies against the early antigen (EA) can be done, but many factors affect anti-EA EBV IgA levels, one of which is ethnicity. AIM: This study aimed to compare levels of anti-EA EBV IgA in NPC patients and non-NPC in the Nias tribe. MATERIALS AND METHODS: This study was cross-sectional involving 29 NPC patients and 29 non-NPC in the Nias tribe. The subjects of the study were blood tests to measure the levels of anti-EA EBV IgA by a serological test. Data were analyzed by Chi-square test. RESULTS: The results showed that the mean value of anti-EA EBV IgA levels is 246.22 ± 320.05 U/mL and the proportion of positive serology tests is 55.2% in NPC patients. The mean value of anti-EA EBV IgA levels is 51.79 ± 1.55 U/mL and the proportion of positive serology tests is 10.3% in non-NPC. The comparison of mean anti-EA EBV IgA between NPC patients and non-NPC was significant (p &lt; 0.001). The comparison of positive and negative serology tests of anti-EA EBV IgA between NPC patients and non-NPC was significant (p &lt; 0.05). CONCLUSION: The serology tests of anti-EA EBV IgA play a role in differentiating NPC patients from non-NPC, so it can be useful as a screening tool for NPC in the Nias tribe.

Horserace Betting Levy Board: codes of practice update

This article summarises the main updates to the Horserace Betting Levy Board codes of practice for 2022. The main points discussed include: the addition of a section on preparation of mares for covering in response to mares being presented with polymerase chain reaction tests for contagious equine metritis only, without appropriate gynaecological preparation and bacteriology; a clarification regarding the swabbing of at-risk or suspected horses for contagious equine metritis; a revision to the guidelines for strangles, highlighting the fact that negative serology tests do not always guarantee absence of the carrier state of strangles; new guidelines on piroplasmosis and the significance of the disease in the UK; an update to the equine influenza vaccine requirements; and the clarification regarding the diagnosis of West Nile fever and the potential significance of the disease to the UK. The importance of constant vigilance regarding infectious diseases and adherence to strict biosecurity protocols is highlighted and the threat of exotic diseases, which could potentially emerge in the UK, is briefly discussed.

Visceral Leishmaniasis: A Case Report of a Challenging Diagnosis After Orthotopic Liver Transplantation

Leishmaniasis is a disease caused by a protozoan and transmitted by sandfly species in several emerging countries. Visceral leishmaniasis is a serious complication, especially in immunosuppressed patients, and is uncommon after liver transplantation. We report the case of a 48-year-old female patient who underwent liver transplantation owing to polycystic liver disease. Six months after the procedure, she was hospitalized with diarrhea, acute kidney failure, and leukopenia. She had been off steroids for 3 months and was taking mycophenolate and tacrolimus. She had already been treated for cytomegalovirus, which was negative on admission. During hospitalization, fever, splenomegaly, ascites, and pancytopenia appeared. Serology for Leishmania by indirect immunofluorescence was negative. Then, bone biopsy and molecular testing for Leishmania diagnosed it as visceral leishmaniasis. Amphotericin therapy was initiated with resolution of fever after 4 days of treatment and gradual recovery from pancytopenia. This case highlights the challenge of early diagnosis of visceral leishmaniasis in liver transplant recipients with diarrhea and leukopenia, which can be caused by immunosuppression or more prevalent viral diseases. Late onset of fever, splenomegaly, and a first negative serologic test also made early diagnosis difficult. The aim of the report is to emphasize the suspicion of visceral leishmaniasis in symptomatic patients from emerging countries and to question the benefit of including protozoan screening in liver transplant donors and recipients in endemic areas.

Elimination of porcine reproductive and respiratory syndrome virus infection using an inactivated vaccine in combination with a roll-over method in a Hungarian large-scale pig herd

BackgroundPorcine reproductive and respiratory syndrome virus (PRRSV) causes severe economic losses worldwide and only four countries in Europe are free from PRRSV. Complete depopulation–repopulation is the safest and fastest, but also the most expensive method for eradicating PRRSV from a population. Another possible way to eliminate an endemic PRRSV infection is to replace the infected breeding stock by gilts reared isolated and protected from PRRSV on an infected farm. With this method it is possible to maintain continuous production on the farm. The authors report the first successful elimination of PRRSV in a Hungarian large-scale pig farm by using an inactivated vaccine and performing segregated rearing of the offspring.Case presentationThe study was performed on a PRRSV infected farm (Farm A) with 1475 sows. The clinical signs of reproductive failure had been eliminated previously by using an inactivated vaccine (Progressis®, Ceva). At the beginning of the elimination programme, gilts intended for breeding were vaccinated at 60 and 90–100 days of age. After that, gilts selected for breeding were vaccinated at 6 months of age, on the 60–70th day of pregnancy and at weaning.Approximately 1200 piglets from vaccinated sows were transported at 7 weeks of age to a closed, empty farm (Farm B) after being tested negative for PRRSV by a polymerase chain reaction (PCR) method, and then were reared here until 14 weeks of age. At this age, all pigs were tested by PRRS ELISA. Seronegative gilts (n = 901) were subsequently transported from Farm B to a third, closed and empty farm (Farm C), and (having reached the breeding age) they were inseminated here after a second negative serological test (ELISA). At the same time, Farm A was depopulated, cleaned and disinfected. All pregnant gilts were transported from Farm C to Farm A after being re-tested negative for antibodies against PRRSV. Follow-up serology tests were performed after farrowing and results yielded only seronegative animals. Based on the subsequent negative test results, the herd was declared PRRSV free by the competent authority.ConclusionsThe presented farm was the first during the National PRRS Eradication Programme of Hungary to eradicate PRRSV successfully by vaccinating the sows with an inactivated vaccine and performing segregated rearing of the offspring. Production was almost continuous during the whole process of population replacement.

Recent HIV infections: evaluation of a simple identification score for newly diagnosed patients.

ABSTRACTOBJECTIVE Recognize incident infection to better characterize the groups that fuel HIV epidemic. We propose a simple score to identify recent infections among newly diagnosed patients as a HIV surveillance tool.METHODS Newly diagnosed patients were defined as recent infections when a negative serological test in the previous year was available. Laboratory tests, such as the avidity index (Bio-Rad, according to the CEPHIA protocol), chemiluminescent intensity (CMIA, architect, Abbott), and the nucleotide ambiguity index of partial pol sequences were used as proxies of recency. A simple score based on clinical symptoms of acute retroviral syndrome during the previous year, CD4+ T cell count, and viral load at admission was tested to assess the predictive power, using receiver operating characteristic (ROC) curves, to identify recent cases of infection.RESULTS We evaluated 204 recently diagnosed patients who were admitted to the Ambulatório de Referência em Moléstias Infecciosas de Santo André (Santo André Reference Infectious Diseases Outpatient Clinic), in the metropolitan region of São Paulo, Brazil, recruited between 2011 and 2018. An HIV-negative test in the year prior to enrollment was documented in 37% of participants. The proportion of cases classified as recent infections (less than one year), according to the laboratory proxies were: 37% (67/181) for an avidity index < 40%, 22% (30/137) for a CMIA < 200, and 68% (124/181) for an ambiguity index < 0.5%. Using different combinations of recency definitions, our score showed an area under the ROC curve from 0.66 to 0.87 to predict recency.CONCLUSIONS Using data from patients’ interviews and routine laboratory tests at admission, a simple score may provide information on HIV recency and thus, a proxy for HIV incidence to guide public policies. This simple for the Brazilian public health system and other low- and middle-income countries.

COVID-19 among workers assisting homeless and socially vulnerable people.

ABSTRACTObjective To describe the profile of professionals assisting homeless and socially vulnerable populations tested for COVID-19, and to determine potential associations with exposure at the workplace, on the way to work, or at home, among infected professionals. To describe disease symptoms and progression and to investigate potential associations with age, sex and exposure at the workplace, on the way to work, or at home.Methods A retrospective analysis of data of 173 workers employed by Serviço Franciscano de Solidariedade tested for SARS-CoV-2. Between May 20 and June 2, 2020, professionals and volunteers were tested for anti-SARS-CoV-2 IgG and IgM antibodies, by means of qualitative rapid chromatographic immunoassay in whole blood. A questionnaire was used to collect data on demographic characteristics and working conditions, history and date of onset of symptoms and risk factors. Quantitative variables were expressed as mean and standard deviation, or median, maximum, and minimum values. Data normality was investigated using the Kolmogorov-Smirnov test.Results A total of 46 (26.6%) participants had positive serologic tests. Of participants with negative serologic test results, 109 (85.8%) were asymptomatic. History of symptoms was the most significant independent factor associated with positive serology. Serologic test results and symptoms differed significantly according to housing (p=0.045) and working (p<0.001) conditions. More than half of participants (52.4%) living in shared households tested positive, compared to 23% of participants living in family households. Participants working remotely from home did not test positive. In seropositive participants, onset of symptoms was associated with workplace exposure and shared housing conditions.Conclusion History of symptoms was associated with positive serology for COVID-19. Shared housing conditions tended to be associated with higher risk of infection. Onset of symptoms was associated with higher levels of workplace exposure and shared housing conditions in seropositive participants.

A comparison of a SARS-CoV-2 rapid-test and serological-test in a Public Health Hospital

Nowadays, with the start of the vaccination campaign is very important to assess the extent of exposure of the population and identifying rapid, sensitive and accurate test to quickly identify new cases of SARS-CoV-2. The rapid test, cheap and easy to perform, is therefore very useful in developing countries, where the vaccination campaign has not yet reached adequate coverage. We compared the VivaDiag COVID-19 IgM/IgG Rapid Test (VivaCheck Biotech Co., Ltd) with the Roche Elecsys Anti-SARS-CoV-2 (Roche Diagnostics, Rotkreuz, Switzerland) to recognize past infections and to compare VivaDiag COVID-19 IgM/IgG Rapid Test (VivaCheck Biotech Co., Ltd) with Abbott Real Time PCR SARS-CoV-2 assay to recognize infection during its acute phase so that it's possible to evaluate the use of commercially available assays in clinical practice. Of the 1,100 patients tested with serological and rapid test, 1,085 were negative both to serological and rapid test, 4 patients were positive at rapid (2 for IgM and 2 for IgG) but negative serological test, 11 patients were positive at serological test but negative to rapid. Of the 300 tested with oropharyngeal swab and rapid test, 294 were negative both to swab and rapid test, 2 positives both to swab and rapid test, 3 positives at swab but negative at rapid test, 1 negative at swab but positive at rapid test. the combined use of these tests according to the specific needs of users, allows a reliable identification of infected patients in the acute phase, distinguishing them from subjects with an antibody response from a previous infection.

Long-term detection of SARS-CoV-2 antibodies after infection and risk of re-infection

ObjectivesTo evaluate long-term sensitivity for detection of total antibodies against SARS-CoV-2 MethodsFrom week 41, 2020, through week 26, 2021, all Danish blood donations were tested for SARS-CoV-2 antibodies with the Wantai assay. The results were linked with polymerase chain reaction (PCR) test results from the Danish Microbiological Database (MiBa). ResultsDuring the study period, 105,646 non-vaccinated Danish blood donors were tested for SARS-CoV-2 antibodies, and 3,806 (3.6%) had a positive PCR test before the blood donation. Among the donors with a positive PCR test, 94.2% subsequently also had a positive antibody test. The time between the positive PCR test and the antibody test was up to 15 months and there was no evidence of a decline in proportion with detectable antibodies over time. A negative serological result test was associated with a higher incidence of re-infection (Incidence Rate Ratio = 0.102 (95% confidence interval (CI): 0.039–0.262)). ConclusionAmong healthy blood donors, 94.2% developed SARS-CoV-2 antibodies after infection, and a lack of detectable antibodies was associated with re-infection.

A case of congenital syphilis despite a negative maternal serological test for syphilis at early gestation

A case of congenital syphilis despite a negative maternal serological test for syphilis at early gestation

SARS-CoV-2 infection among Brazilian dentists: a seroprevalence study.

This cross-sectional study aimed to determine the seroprevalence of SARS-CoV-2 infection among Brazilian dentists and its associated factors. Stratified random sampling of dentists from 33 administrative regions of the Federal District (Brazil) was performed. The presence of antibodies was verified by the OnSite COVID-19 IgG/IgM Rapid Test. Participants answered a survey about sociodemographic characteristics, exposure to COVID-19, and professional practice. A chi-square test was performed between serostatus and exposure variables. Mann-Whitney tests were carried out for quantitative variables. Odds ratio (OR) and 95% confidence intervals (95%CI) were calculated. A series of binomial logistic regression models was performed. The seroprevalence of SARS-CoV-2 infection among 324 selected dentists was 19.1%. There was a statistically significant association between seropositivity and previous confirmed diagnosis of COVID-19, loss of taste or smell, diagnosis of COVID-19 in a household member, and treatment of a patient with fever. Dentists with a previous confirmed diagnosis of COVID-19 had 29.5 [12.7-68.4] higher odds to exhibit positive serology test results. Dentists with confirmed diagnosis of COVID-19 in a household member had 2.5 [1.1-5.3] times higher odds to exhibit positive serology test results. Professionals with loss of taste or smell in the last 15 days had 5.24 [1.1-24.1] times higher odds to exhibit positive serology test results, and, for those who had treated patients with fever, there were 2.99 [1.03-8.7] times higher odds to exhibit negative serology test results. There was a similar prevalence rate of infection among dentists and in the general population. Nevertheless, this finding applies to the epidemiological situation in 2020, before the development of vaccines and the emergence of SARS-CoV-2 Delta variant.

Coronavirus disease 2019 (COVID-19) vaccine intentions and uptake in a tertiary-care healthcare system: A longitudinal study.

Healthcare workers (HCWs) are a high-priority group for coronavirus disease 2019 (COVID-19) vaccination and serve as sources for public information. In this analysis, we assessed vaccine intentions, factors associated with intentions, and change in uptake over time in HCWs. A prospective cohort study of COVID-19 seroprevalence was conducted with HCWs in a large healthcare system in the Chicago area. Participants completed surveys from November 25, 2020, to January 9, 2021, and from April 24 to July 12, 2021, on COVID-19 exposures, diagnosis and symptoms, demographics, and vaccination status. Of 4,180 HCWs who responded to a survey, 77.1% indicated that they intended to get the vaccine. In this group, 23.2% had already received at least 1 dose of the vaccine, 17.4% were unsure, and 5.5% reported that they would not get the vaccine. Factors associated with intention or vaccination were being exposed to clinical procedures (vs no procedures: adjusted odds ratio [AOR], 1.39; 95% confidence interval [CI], 1.16-1.65) and having a negative serology test for COVID-19 (vs no test: AOR, 1.46; 95% CI, 1.24-1.73). Nurses (vs physicians: AOR, 0.24; 95% CI, 0.17-0.33), non-Hispanic Black (vs Asians: AOR, 0.35; 95% CI, 0.21-0.59), and women (vs men: AOR, 0.38; 95% CI, 0.30-0.50) had lower odds of intention to get vaccinated. By 6-months follow-up, >90% of those who had previously been unsure were vaccinated, whereas 59.7% of those who previously reported no intention of getting vaccinated, were vaccinated. COVID-19 vaccination in HCWs was high, but variability in vaccination intention exists. Targeted messaging coupled with vaccine mandates can support uptake.

Clinical and epidemiological characterization in the follow-up of newborns with COVID-19: a descriptive study.

COVID-19 disease affects newborns, but its middle and long-term effects are still unclear. To describe the clinical and epidemiological characteristics and follow-up of newborns infected with SARS-CoV-2. An observational and descriptive study. We included newborns with SARS-CoV-2 positive RT-PCR born from SARS-CoV-2 seropositive mothers. Delivery and newborn care were provided at the 'Instituto Nacional Materno Perinatal' from Peru between June 1 and September 30, 2020. Perinatal information was collected from medical records. Remote follow-up and face-to-face evaluations gathered epidemiological and clinical information, in addition to serological and RT-PCR tests for SARS-CoV-2. Descriptive statistics were used for analysis. During the study period, 4733 neonates were born at the institution. We found that 1488 (31.4%) were born from seropositive for SARS-CoV-2 mothers. Finally, we included the 34 (2.3%) newborns with positive RT-PCR for SARS-CoV-2. Regarding the included newborns, 29.4% were delivered by cesarean section, 26.5% had low birth weight, 11.8% were preterm, 26.5% were hospitalized, and one died. Twenty-eight had a remote follow-up, and 18 also had a face-to-face follow-up. A total of 64.3% were exclusively breastfed, 28.6% were mixed breastfed, and 7.1% used a substitute formula. The face-to-face evaluation was performed between one and four months of chronological age. We found that 100% had negative control RT-PCR test for COVID-19, 38.9% had a negative serological test (IgM, IgG), and 61.1% positive IgG. Neonatal SARS-CoV-2 infection is rare, and most infected infants are asymptomatic. Vaginal delivery, breastfeeding, and joint isolation did not related with complications during hospital care. Infants under remote and in-person follow-up showed favorable clinical evolution during the study period.

CLINICAL PROGRESSION OF LEPROSY IN EURASIAN RED SQUIRRELS (SCIURUS VULGARIS) IN A NATURALLY INFECTED WILD POPULATION.

Leprosy has been described in Eurasian red squirrel (Sciurus vulgaris; ERS) carcasses since 2014. Studies of ERS carcasses have not provided information about incubation or disease progression in this host but have provided important insights into pathogen presence and distribution throughout the United Kingdom. Here we present field study data on 31 live ERS from an island population naturally infected with Mycobacterium leprae that were assessed longitudinally over a 2-yr time period. Clinical assessment, serologic (anti-phenolic glycolipid-I antibody [αPGL-I] detection) and molecular methods (polymerase chain reaction) were used to diagnose and categorize ERS at each assessment as a leprosy case, a leprosy suspect, colonized by M. leprae, or a contact ERS. Eight ERS (25.8%) were identified as leprosy cases: four at initial assessment, two at 6 mon and two at 24 mon after initial assessment. One ERS was categorized a leprosy suspect when it developed typical lesions 12 mon after initial assessment, despite negative serologic and molecular test results at this time, though M. leprae DNA had been isolated during the initial assessment. Seven ERS (22.6%) were categorized as colonized and of these, six were reassessed but did not develop clinical signs of leprosy within 6 (n = 2), 12 (n = 3), and 18 (n = 1) mon. Most (48.4%, n = 15) were categorized as contact ERS. Progression of leprosy lesions varied between ERS, but always increased in severity over time and was paralleled with increased antibody response. Based on our dataset, we propose the hypotheses: 1) leprosy in ERS is a chronic, slowly progressing disease in this species, similar to that described for other hosts; 2) lesions can undergo repeated ulceration-healing cycles; and 3) in some instances M. leprae DNA and αPGL-I antibodies are detectable before the onset of clinical signs of disease. Future studies addressing the progression of leprosy in ERS should follow affected animals over a longer time period and include tissue samples to pair molecular diagnostics with serologic results.