Positive PCR Test Results Research Articles

Effectiveness of laboratory tests in tracking severely COVID-19 infections

AIM: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a virus that causes COVID-19 (Coronavirus Disease 2019), and poses serious difficulties in terms of healthcare systems and global public health. With the large number of publications on COVID-19, clinicians need a synthesis of evidence to provide guidance when dealing with patients with COVID-19. Emerging studies reveal the existence of numerous demographic, clinical, immunological, biochemical and radiographic data that may be useful for clinicians to predict the severity and mortality of COVID-19. The aim is of this study; To determine laboratory parameters that can predict the course and severity of COVID-19 disease in patients with diagnosed solely SARS-CoV 2 PCR test positivity results and independently of the clinic status of selected patients and based on laboratory findings. MATERIALS AND METHODS: This study is a retrospective cross-sectional study conducted at Karacabey State Hospital between January and April 2022. Among the patients who applied to the COVID-19 outpatient clinic, 469 patients (261 females, 208 males) over the age of 18 and positive for SARS-CoV-2 RT-PCR were included in the study. The patients were divided into groups as outpatients, inpatients and patients in need of intensive care (intensive care unit, ICU). Demographic data (age, gender), COVID-19 RT-PCR results, and simultaneous laboratory parameters of the patients were scanned retrospectively. RESULTS: When CRP, urea, ferritin, LEU, NEU, MONO, RBC, HGB, HCT, MCV, NLR, PLR, CRP-NR, and SII index values were taken into consideration, a statistically significant difference was found between the groups. Creatinine, ALT, AST, LDH, troponin I, mass CK-MB, D dimer, LYM, EOS, PLT, ELR, and PNR values were not significantly different between the groups. CONCLUSIONS: Advantages of this study; Comparing the changes in the patient's other laboratory findings based on a single positive PCR test result and finding meaningful rates in terms of serious covid risk. The disadvantage of this study is that it is a study independent of the patient's clinic and disease stage. CRP, urea, ferritin, and indexes such as NLR, PLR, CRP-NR, and SII index values can be used to predict the severity of the disease.

High Prevalence of Unconfirmed Positive HIV PCR Test Results among African Infants with HIV Exposure in the International epidemiology Databases to Evaluate AIDS (IeDEA) Consortium.

In a large, multi-regional cohort of African infants with HIV exposure, 44% of those with a positive HIV PCR lacked a confirmatory positive test. Efforts are needed to ensure high-fidelity implementation of HIV testing algorithms, so that all positive results are confirmed thereby reducing the risk of potentially false-positive results.

Passive surveillance for shrimp pathogens in Penaeus vannamei submitted from 3 regions of Latin America

Multiple PCR analyses were conducted to broaden the search spectrum for shrimp pathogens, revealing some pathogens without histological lesions. This underscores the importance of selecting appropriate primers for obtaining reliable results. Notably, there was significant variability among primers, emphasizing the need for seasonal and regional assessment to optimize primer selection. It's crucial to understand that a positive PCR test result alone doesn't confirm the presence of a viable pathogen or a disease state. Therefore, histological analysis was employed to confirm the presence of characteristic lesions for each pathogen. Overall, most shrimp exhibited coinfections, including WzSV8, DHPV, chronic midgut inflammation, and tubule distension/epithelial atrophy consistent with AHPND. Additionally, non-EHP-microsporidia, striated muscle necrosis in the abdomen, and gregarines in the hindgut caecum were observed. The presence of spheroids in the lymphoid organ might indicate host responses to often unidentified causes.

Jerusalem's CoVID-19 Experience-The Effect of Ethnicity on Disease Prevalence and Adherence to Testing.

The management of the SARS-CoV-2 pandemic depends amongst other factors on disease prevalence in the general population. The gap between the true rate of infection and the detected rate of infection may vary, especially between sub-groups of the population. Identifying subpopulations with high rates of undetected infection can guide authorities to direct resource distribution in order to improve health equity. A cross-sectional epidemiological survey was conducted between April and July 2021 in the Pediatric Emergency Department of the Shaare Zedek Medical Center, Jerusalem, Israel. We compared three categories: unconfirmed disease (UD), positive serology test result with no history of positive PCR; confirmed disease (CD), history of a positive PCR test result, regardless of serology test result; and no disease (ND), negative serology and no history of PCR. These categories were applied to local prevailing subpopulations: ultra-orthodox Jews (UO), National Religious Jews (NRJ), secular Jews (SJ), and Muslim Arabs (MA). Comparing the different subpopulations groups, MAs and UOs had the greatest rate of confirmed or unconfirmed disease. MA had the highest rate of UD and UO had the highest rate of CD. UD significantly correlated with ethnicity, with a low prevalence in NRJ and SJ. UD was also associated with larger family size and housing density defined as family size per number of rooms. This study highlights the effect of ethnicity on disease burden. These findings should serve to heighten awareness to disease burden in weaker populations and direct a suitable prevention program to each subpopulation's needs. Early awareness and possible intervention may lower morbidity and mortality.

Estimating the Size of the Hidden Population of COVID-19.

An asymptomatic population has the same infection as symptomatic individuals, so these individuals can unknowingly spread the virus. It is not possible to predict the rate of epidemic growth by considering only the identified isolated or hospitalized population. In this study, we want to estimate the size of the COVID-19 population, based on information derived from patients visiting medical centers. So, individuals who do not receive a formal diagnosis in those medical centers can be considered as hidden. To estimate the Bayesian size of the hidden population of COVID-19 a respondentdriven sampling (RDS) method was used. Twenty-three people infected with COVID-19 seeds and who had positive PCR test results were selected as seeds. These participants were asked whether any of their friends and acquaintances who had COVID-19 did not visit a medical center or hid their illness. Access to other patients was gained through friendship and kinship, hence allowing the sampling process to proceed. Out of 23 selected seeds, only 15 seeds remained in the sample and the rest were excluded due to not participating in the further sampling process. After 5 waves, 50 people with COVID-19 who had hidden their disease and were not registered in the official statistics were included in the sample. It was estimated that 12,198 people were infected with COVID-19 in Khalkhal city in 2022. This estimate was much higher than recorded in the official COVID-19 statistics. The study findings indicate that the estimated 'true' numbers of COVID-19 patients in one town in Iran were significantly higher compared to the official numbers. The RDS method can help capture the potential size of infections in further pandemics or outbreaks globally.

Relationship of ACE1 and ACE2 genetic polymorphisms on SARS-CoV-2 infection and severity of symptoms in different regions of Iraq

This study was conducted in the laboratories of the Biology Department - College of Science - Tikrit University, the laboratories of the Food Science Department - College of Agriculture - University of Anbar, and the Public Health Laboratories - Anbar for the period from December 2021 AD until February 2022 AD, study involved taking samples from hospitalized COVID-19 patients of both sexes, after a confirmed positive PCR test result. As well as those lying in quarantine in three Iraqi governorates (the isolation unit in Karkh, Yarmouk and Kadhimiya hospitals, the Al-Shifa quarry hospital in Anbar, the public health laboratory in Anbar, and the quarantine hospital for thousands in Erbil), in addition to outpatient clinics. They were distributed by 30 patients and 20 healthy subjects from each governorate, with ages ranging from 18-80 years, randomly to men and women in order to determine the role of genetic polymorphisms in the ACE inhibitor gene in the study samples. The results of the genetic polymorphisms of ACE-1rs4646994, ACE-2rs2106809, and ACE-2rs4240157 showed that there were non-significant differences between the frequency of alleles and genotypes in the patient's group compared with the healthy group. The DD mutant genotype of ACE-1rs4646994 appeared in the patient's group in Baghdad and Anbar with a high percentage, while patients in Erbil showed the highest percentage of the heterozygous genotype ID compared to healthy subjects, with an OR= 0.922, OR= 2.750, and OR= 1.118, respectively, for the mutant allele D. Therefore, it is not considered a risk factor for the disease in Baghdad, in contrast to Anbar and Erbil. The polymorphism of ACE-2rs2106809, the homozygous genotype CC was dominant in patients in the aforementioned provinces and may not be considered a risk factor for the disease. The results of ACE-2rs4240157 gene polymorphism, the heterozygous CT genotype showed a high percentage in patients in Baghdad and, while in Anbar patients, the normal genotype TT appeared to be the highest percentage compared to healthy subjects. The C mutant allele in Baghdad, Anbar, and Erbil patients reached OR= 1.306, OR= 4.333, and OR= 9.00, respectively, so this allele is considered a risk factor for the disease. We can conclude from this study the role of each of the polymorphisms rs4646994 ACE-1 and rs4240157 ACE-2 in infection with COVID-19 and the severity of its symptoms according to the geographical region and race, in contrast to rs2106809 ACE-2, as it is possible to conduct clinical studies to demonstrate the role of genetic polymorphisms with Relationship to diseases depending on the region and race.

Asymptomatic Leishmania infantum infection in dogs and dog owners in an endemic area in southeast France.

The prevalence of asymptomatic leishmaniasis in dogs and their owners in the main endemic areas of France has not been studied to date. The objective of this study was to quantify asymptomatic Leishmania infantum infection in southeast France in healthy people and their dogs using molecular and serological screening techniques. We examined the presence of parasitic DNA using specific PCR targeting kinetoplast DNA (kDNA) and specific antibodies by serology (ELISA for dogs and Western blot for humans) among immunocompetent residents and their dogs in the Alpes-Maritimes. Results from 343 humans and 607 dogs were included. 46.9% (n=161/343) of humans and 18.3% (n=111/607) of dogs were PCR positive; 40.2% of humans (n=138/343) and 9.9% of dogs (n=60/607) were serology positive. Altogether, 66.2% of humans (n=227) and 25.7% of dogs (n=156) had positive serologies and/or positive PCR test results. Short-haired dogs were more frequently infected (71.8%, n=112) than long-haired dogs (12.2%, n=19) (p=0.043). Dogs seemed to be more susceptible to asymptomatic infection according to their breed types (higher infection rates in scenthounds, gun dogs and herding dogs) (p=0.04). The highest proportion of dogs and human asymptomatic infections was found in the Vence Region, corresponding to 28.2% (n=20/71) of dogs and 70.5% (n=31/44) of humans (4.5/100,000 people). In conclusion, the percentage of infections in asymptomatic humans is higher than in asymptomatic dogs in the studied endemic area. It is questionable whether asymptomatic infection in humans constitutes a risk factor for dogs.

Evaluation of the relationship between TAFI level and prognosis in COVID-19 patients.

Serum thrombin-activated fibrinolysis inhibitor (TAFI) levels were measured in coronavirus disease 2019 (COVID-19) patients requiring intensive care, clinical hospitalization, and outpatient follow-up. The relationships between serum TAFI levels and prognosis were determined. Ninety patients who had positive COVID-19 PCR test results were randomly selected and included in the study. Subgroups were formed according to the clinical characteristics of the patients as follows: mild, moderate, and severe. Venous blood samples were taken from all patients, and serum C-reactive protein (CRP), lactate dehydrogenase (LDH), fibrinogen, D-dimer, ferritin, and TAFI levels were measured. The results were evaluated by comparing each group. The one-way ANOVA test to determine differences between subgroups resulted in p-values lower than 0.05 for all biochemical analytes (CRP, LDH, fibrinogen, D-dimer, ferritin, and TAFI). Regarding serum TAFI levels, there were significant differences in the severe group (853.04 ± 338.58 ng/mL) compared to the mild group (548.33 ± 264.17 ng/mL). ROC curve analysis to predict mortality revealed that TAFI levels were able to detect 85% of deaths. In addition, ROC analysis revealed that serum TAFI levels could detect 86% of intubated cases. The disease progression is more severe in patients with high TAFI levels, and high TAFI levels are associated with mortality and intubation rates. Further studies are needed to determine serum TAFI levels as a biomarker of prognosis in COVID-19 patients.

PCR-confirmed malaria among children presenting with a decreased level of consciousness in Angola: a prospective, observational study

BackgroundIn malaria-endemic areas, children presenting to hospitals with a decreased level of consciousness remain a diagnostic dilemma. The definition of cerebral malaria in a comatose child demands exclusion of other possible reasons, which requires in-depth investigations that are not easily available. The aim of this study was to investigate the frequency and clinical characteristics of PCR-confirmed malaria in a cohort of children with a decreased level of consciousness, look for potential features that would aid in differentiating children with malaria from those without, and assess the performance of traditional thick film microscopy against the cytb-qPCR-method.MethodsA total of 345 children aged 30 days–15 years old, presenting to Hospital Pediátrico David Bernardino in Luanda, Angola, with a decreased level of consciousness (Glasgow coma scale score < 15) were prospectively enrolled during 2014–2017. Malaria was defined as a positive cytb-qPCR result on any occasion in hospital. The clinical course and laboratory parameters were compared between children with malaria and those without. The performance of thick film microscopy was analysed against the PCR method.Results161 of 345 children (46.7%) had a positive malaria PCR test result. All cases were Plasmodium falciparum species, and 82.6% (133/161) fulfilled the WHO criteria for severe malaria. Overall, children with malaria presented to hospital with a shorter duration of symptoms and less convulsions pre-admission compared to those without malaria. The median GCS score on admission was 8, which did not differ between children with or without malaria. Clinical findings on admission were mostly similar across the whole cohort, but an infection focus outside the central nervous system was more common in malaria-negative children. Moreover, severe anaemia, thrombocytopenia, and high CRP levels occurred more frequently in children with malaria. The case fatality ratio was 28.5% (91/319) and did not differ between parasitaemic children and those without malaria, although parasitaemic children died sooner after hospital admission. When neurological sequelae were also considered, a positive malaria test was associated with a better outcome. The performance of thick film microscopy against PCR yielded a sensitivity of 96.8% and a specificity of 82.7%.ConclusionsIn this cohort of children with a decreased consciousness, the frequent presence of a malarial infection could not be judged from the clinical findings on admission, but the combination of profound aneamia, thrombocytopenia, and a high CRP level increased the odds of a positive malaria test result. Mortality remained high regardless of etiology, but malaria infection associated with fewer neurological deficits at discharge. Thick film microscopy performed well compared to the cytb-qPCR method.

Utility of RT-PCR versus electronic track and trace system for pre-procedural COVID-19 screening- a retrospective cohort study

Background and aimsCOVID-19 has disrupted the patient workflow in all healthcare settings. Procedures such as bronchoscopy and spirometry require additional pre-procedure screening for SARS-CoV-2. However, there is uncertainty regarding the utility of this universal pre-procedure screening. The State of Qatar has a robust contact tracing system in place in the form of the mobile application ‘Ehteraz.’ This study assesses the utility of various pre-procedural screening measures in asymptomatic patients and generate recommendations for any potential improvement in the workflow. MethodsThis is a cross-sectional study of asymptomatic patients who had SARS-CoV-2 RT-PCR screening performed before bronchoscopy or lung function testing scheduled on an elective basis. Descriptive statistics were used to summarize and determine the sample characteristics. The rate of the positive PCR test result was subsequently calculated. ResultsTwo patients (0.34%) tested positive for COVID-19 on their pre-procedural screen. Four patients (0.68%) had an inconclusive result. ConclusionThe positivity rate of SARS-CoV-2 RT-PCR is extremely low in asymptomatic individuals screened before bronchoscopy and spirometry. The authors recommend pre-procedural symptom and electronic application-based contact screening instead of universal pre-procedural SARS-CoV-2 RT-PCR for screening asymptomatic individuals.

COVID-19 Enfekte Hastalarda Tromboembolik Olayların Araştırılması

Aim: In this study, we sought to determine patient characteristics and clinical outcomes of patients who experience this complication, as well as the frequency of thromboembolic events (TEE) in COVID-19 patients hospitalized. Materials and Methods: Between January 2020 and December 2021, all the patients with positive COVID-19 PCR test results were enrolled in this study. The data of the cases that developed TEE with the diagnosis of COVID-19 were evaluated retrospectively. Results:During this time, 2,845 inpatients were admitted with COVID-19. Among this group, 96 patients (3.37%) had COVID-19 - related TEE. The mean age was 63.76±13.85 years (range, 28–80 years) with 46 men (47.92%) and 50 women (52.08%). Of the patients, 46 of 96 (47.92%) had severe COVID-19, and 50 of 96 (52.08%) had only mild respiratory symptoms. Severe COVID-19 group patients were older but there was not statistically significance between the groups. Peripheral venous disease was more common in mild COVID-19 group, while peripheral arterial disease is more common in severe COVID-19 group.CRP, uric acid, troponin, creatinine,D-dimer and leukocyte levels were higher in severe COVID-19 patients with TEE (p&amp;lt;0.05). Peripheral venous disease was present in 81 of 96 (84.37%), peripheral arterial disease in 5 of 96 (5.2%), and pulmonary embolism in 11 (11.45%) cases. One patient (1.04%) had both peripheral venous disease and pulmonary embolism. The overall mortality was 6.25% (6/96). Conclusion: COVID-19-associated thrombotic process affects more frequently veins than arteries. Given the significant observed risk for TEE in COVID-19, diagnostic imaging for TEE should be evaluated with a high degree of clinical suspicion.

COVID-19 and the ageing immune system in an elderly patient : a case report

BackgroundThe severity of COVID-19 infection has an increasing trend in the elderly, which contributes to the high morbidity and mortality rates in this population. Aging itself is a prominent risk factor for severe disease and death from COVID-19. Case DescriptionThis case report a 71-year-old woman who complained of shortness of breath for 3 days before being admitted to the hospital. Bilateral consolidation and increased bronchovascular pattern were found on chest radiograph, and a positive SARS-COV2 nasopharyngeal swab PCR test result was noted. This patient was diagnosed with confirmed severe manifestation of COVID-19, community-acquired pneumonia and type 1 respiratory failure, as well as type II diabetes mellitus and suspicion of acute gastritis. The results of the geriatric status assessment were moderate functional status, risk of malnutrition, and moderate risk of deep vein thrombosis (DVT). This patient underwent treatment in accordance with the COVID-19 protocol along with management for geriatric status improvement. The patient was given permission to return home after 14 days of treatment, during which time her health had improved and her functional status had changed to moderate dependency. During follow-up, the patient continued to receive therapy. She is still being observed and future evaluations will be conducted. ConclusionThe increased susceptibility of the elderly to COVID-19 infection is caused by various factors. A burden of death and long-term disability brought on by this pandemic may be lessened by new or modified therapies that target aging-associated mechanisms. Therefore, COVID-19 case management in this population should be done with a comprehensive approach.

The effect of interferon in the therapy of severe coronavirus infection.

So far, several protocols have been used for the treatment of coronavirus disease-2019 (COVID-19). In this study, we aimed to study the effect of interferon on the treatment of hypoxemia caused by COVID-19. This was a quasi-experiment with a nonequivalent group design. All participants were admitted to Shahid Beheshti Hospital, Qom province. In total, 60 patients were enrolled in the study, and inclusion criteria were age over 18 years, positive PCR test result, pulmonary involvement in computed tomography (CT) scan, and SpO2 level below 93%. Individuals were divided into two control (hydroxychloroquine + lopinavir/ritonavir [Kaletra]) and intervention (hydroxychloroquine + lopinavir/ritonavir [Kaletra] + interferon-β 1a [recigen]) groups. The data were analyzed in Stata/SE 14.2 using Chi-square, t-test, and Mann-Whitney U test. The mean ± standard deviation (SD) age of patients was 63 ± 16.12 years and 43.3% were male. In terms of outcome variables, 20% of patients in the intervention group and 53.3% of subjects in the control group died and this difference was significant (P = 0.007). According to the quick sequential organ failure assessment (qSOFA) score, the severe cases were 16.7% in the intervention group and 50% in the control group (P = 0.006). In addition, the median days of hospitalization were 11.5 days-significantly higher than those in the control group (5.5 days) (P < 0.001). Based on the results of this study, the use of interferon in the treatment of COVID-19 can improve health and reduce the severity of the disease and mortality.

Evaluation of PCR Negativity in Respiratory Specimens of COVID-19 Patients After Hydroxychloroquine and/or Favipiravir Treatment

Objective: We evaluated PCR negativity in oropharyngeal and nasopharyngeal secretions of COVID-19 patients at the end of hydroxychloroquine and/or favipiravir treatments. Methods: Study inclusion criteria were being hospitalized, being older than 18 years, PCR positivity in oropharyngeal and nasopharyngeal secretions and being tested for SARS CoV-2-RNA PCR after treatment. Initially hydroxychloroquine treatment (group 1) was administered to the patients according to COVID-19 guide of Health Ministry. Favipiravir (group 2) alone or in combination with hydroxychloroquine (group 3) was administered to patients who were unresponsive to hydroxychloroquine or had severe pneumonia or were admitted to intensive care unit. Control respiratory specimens were taken no earlier than 24 hours, after the end of therapy. Repeated tests with 24–48-hour intervals were performed in patients with still positive PCR test results. The detection of SARS CoV-2-RNA was made by real-time PCR. Results: The study group included 492 patients who received treatment. Mean duration of symptoms was similar among three groups. PCR negativity rate was 52.8% in the specimens taken 24 hours after the end of treatment. PCR negativity rates was 27.9% (200/492) in 48 hours after the end of treatment, %13.8 (123/492) in 72nd hour and %3.8 (80/492) in 96th hour. The ratios of PCR negativity for all specimen days were similar in three groups. There was no statistically significant difference between the groups for time to PCR negativity from the date of positivity and after the end of treatment. We determined that early or late treatment did not make a difference in terms PCR negativity time. Conclusion: No difference was found in terms of the ratios of PCR negativity or time for negativity in oropharyngeal and/or nasopharyngeal specimens taken after the end of treatment in COVID-19 patients receiving hydroxychloroquine and/or favipiravir treatment.

Change of pulmonary function tests in hospitalized COVID-19 patients at third and sixth month follow-up.

The effect of COVID-19 infection on pulmonary function is unknown. This study aimed to evaluate pulmonary function tests (PFTs) of patients hospitalized with the diagnosis of COVID-19 pneumonia at 3 and 6 months post-discharge. Patients aged 18 years and over who had positive COVID-19 PCR test results and were hospitalized in the pandemic service between 1 May 2020 and 31 October 2020, were included in the study. All patients were evaluated with PFTs FVC, FEV1, FEV1/FVC, and FEF25-75 at 3 and 6 months after discharge. The mean age of 34 patients included in the study was 47.7 ± 12.7 years. The FVC, FEV1, FEV1/FVC, and FEF25-75 measurements at 3 and 6 months post-discharge showed no significant difference (P = 0.765, P = 0.907, P = 0.707, and P = 0.674, respectively). There was no significant difference in any PFT measurements at the third month follow-up, regardless of the pharmacological treatment protocols applied during hospitalization (P > 0.05). However, FEV1/FVC and FEF25-75 levels were 83.1 [3.4]% and 91.0 [10.0]%, respectively, in those who received systemic steroid treatment, and 78.3 ± 8.5% and 72.5 ± 25.7% in those who did not (P = 0.019 and P = 0.048, respectively). In addition, FVC and FEV1 levels increased significantly from the third to the sixth month follow-up in patients who received systemic steroid therapy (P = 0.035 and P = 0.018, respectively). Although there is no significant difference in PFT measurements from 3 to 6 months in COVID-19 patients, systemic steroid therapy may have a beneficial effect on respiratory function in COVID-19 patients.

THE SUBSEQUENT IMPACT OF COVID-19 FOR BOTH IMMUNE DYSREGULATION AND OPPORTUNISTIC INFECTIONS

THE SUBSEQUENT IMPACT OF COVID-19 FOR BOTH IMMUNE DYSREGULATION AND OPPORTUNISTIC INFECTIONS

Investigation of Humoral and Cellular Immunity in TOBB ETÜ Hospital Workers After Three Doses of CoronaVac Vaccination and after One Dose of Comirnaty Vaccination Following Two Doses of CoronaVac

The Coronavirus disease 2019 (COVID-19) pandemic still continues around the world by making peaks with different variants. In the fight against COVID-19, vaccination is currently the only protective measure. In Turkey, vaccination started firstly in healthcare workers on 13 January 2021 with the CoronaVac (Sinovac Biotech, Chinese) vaccine, and booster doses were administered with the CoronaVac and Comirnaty vaccines in July 2021. In this cross-sectional study, it was aimed to determine the humoral and cellular immunity levels of the employees of the TOBB ETU Hospital 2.5-3.5 months after three doses of vaccination and identify the effective factors. With the power analysis that was conducted with the G*Power software, it was determined to be suitable to include 40 TOBB ETU Hospital workers who had their third dose with the CoronaVac vaccine and 60 workers of the same hospital who had their third dose with the Comirnaty (Pfizer Biontech, Germany) vaccine, and age- and sex-matching was considered by selecting 60 workers randomly from among 223 workers who had Comirnaty as their third dose. The study excluded individuals who had a previous COVID-19 infection or had a positive PCR test result. After collecting blood samples on 18-22 October 2021, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immunoglobulin G levels were studied with the chemiluminescence immunoassay method using a Beckman-Access device (Beckman Coulter Inc., CA, USA) for humoral immunity, and T-SPOT test (T-SPOT. COVID SARS-CoV-2 test-Oxford Immunotec, Singapur) was carried out for cellular immunity. Additionally, demographic data, habits, personal information such as weight and height, reasons for choosing the vaccine and post-vaccine side effects were obtained through the data collection form. Data collection was completed on 29 November 2021. As a result, among the healthcare workers who had received their third dose of vaccine with Comirnaty and CoronaVac; while 25% of those who received three doses of CoronaVac had humoral immunity, 93.3% humoral immunity was determined in the heterogeneous vaccine group with two doses of CoronaVac and one dose of Comirnaty vaccine (p<0.05). Cellular immunity was found to be higher (88.3%, 70%) in those who received the heterologous vaccine than those who completed three doses of the same vaccine (p<0.05). In the heterogeneous vaccination group consisting of the healthcare workers who had their third vaccine dose with Comirnaty and those who had it with CoronaVac, humoral and cellular immunity levels were found high. Among the participants whose humoral immunity was found negative, cellular immunity was present in 75% of those who had Comirnaty as their third dose and 63.3% of those who had CoronaVac. While no significant relationship was found between immunity levels and age, sex or body mass index (BMI), the levels of both forms of immunity were lower in those who had chronic diseases. Among the participants, physicians preferred the third dose of Comirnaty vaccine at a rate of 71.4% and laboratory workers preferred this vaccine at a rate of 80% according to the workplace. In the third dose vaccine preference reasons, it was stated that 55% would continue with the same vaccine, experience fewer side effects, 44% provide more immunity and 9% do not prevent going abroad. The incidence of side effects after the third dose of vaccine was 53% higher in those who received the Comirnaty vaccine than in those who received CoronaVac (35%). Based on these data, it was concluded that heterologous vaccination should be preferred in vaccination strategies, and knowing cellular immunity levels is important for the decision. There is a need for more comprehensive and follow-up studies on how long humoral and especially cellular immunity lasts.

Post-Acute Sequelae of SARS-CoV-2 Infection: A Descriptive Clinical Study.

The investigators aimed to describe the clinical experience of a single center reporting on neuropsychiatric findings among patients experiencing persistent symptoms as part of post-acute sequelae of SARS-CoV-2 (PASC) infection. Data were collected retrospectively (between February 2020 and May 2021) from a cohort (N=100) within a COVID-19 survivors study of patients with persistent symptoms enrolled after a short inpatient stay or who had been outpatients never hospitalized. Patients without confirmatory positive PCR or antibody diagnostic test results were grouped separately as presumptive cases (N=13). Of the 87 patients with confirmed SARS-CoV-2, 63 (72.4%) were female, and 65 (74.7%) were White. The mean age was 49.2 years (SD=14.9). The most prevalent symptoms after COVID-19 infection were fatigue, "brain fog," headache, anxiety, and sleep issues. Attention and executive function were frequently impaired. The mean Montreal Cognitive Assessment score was 26.0 (SD=2.8). Concentration and attention as well as memory issues were both significantly correlated with the complaint of brain fog. These preliminary findings suggest that post-acute sequelae of SARS-CoV-2 vary in frequency and duration with relation to premorbid history and that these conditions affect functional domains and patients' ability to return to work. Longitudinal research with larger cohorts is needed to characterize PASC and to optimize care, especially for vulnerable populations.

Mandatory Testing in Schools can Significantly Reduce Underreporting of COVID-19 Infections Among Students with in-Class Teaching Compared to Home Schooling

Aim of the study The aim of this was to study investigate the effectiveness of mandatory Covid-19 tests for in-classroom teaching in reopened schools as a containment measure in the pandemic. In Bavaria, mandatory testing at schools was implemented directly after the Easter vacations in 2021. For the first week after the vacations, this resulted in a natural experiment that allowed us to quantify the impact of the new testing strategy on reported Covid-19 cases.Methods We compared changes in the reported 7-day incidence of new infections between districts with in-classroom teaching at school and districts with closed schools. During the calendar week 15, districts with reported incidences below 100 were allowed to reopen schools and have in-classroom teaching if mandatory COVID-19 testing was performed at school with rapid antigen tests. We do not have data on the rapid test results; however, positive test results in the rapid antigen test were verified by a PCR test, and cases of positive PCR test results were reported at the district level by age groups. In the calendar weeks 13 and 14, all schools in Bavaria were closed due to Easter vacations. Taking into account a latency period of about 3-4 days and a reporting period of 1-2 days, this means that any additional increase in reported incidences for districts with in-class teaching and mandatory testing in the week after the vacation cannot be attributed to transmissions at schools, but reflects the reduction of underreporting due to the newly implemented testing strategy.Results Reported incidence increased by a factor of 6.6 for 5-11 year old and by 1.7 for 12-20 year old pupils in districts with in-classroom teaching and mandatory testing at schools. This increase was accompanied by a reduction in underreporting and was significant compared to districts with school closure. Given the situation of a natural experiment, this increase in the reported incidence among school children can be attributed to the testing strategy. For the same time period, no differences in reported incidences were found for the other age groups.Conclusion In-class teaching with mandatory testing in reopened schools changes the role of schools in the pandemic. Our analyses show that reopening schools with a mandatory testing approach is beneficial from an epidemiologic perspective as it can strongly reduce the dark figure of COVID-19 cases among children.

Urban and sub-urban disparities in health outcomes among patients with COVID-19; a cross-sectional study of 234 418 patients in Iran

BackgroundIt remains crucial to understand socio-demographic determinants of COVID-19 infection to improve access to care and recovery rates from the disease. This study aimed to investigate the urban and sub-urban disparities associated with COVID-19 in patients visiting healthcare facilities in the province of Tehran, Iran.MethodsData from 234 418 patients who were diagnosed with COVID-19 infection from March 2020 to March 2021 in the province of Tehran were used in this analysis. Descriptive statistics were used to describe the characteristics of the study population. Chi-Squared test was applied to examine the association of study variables with residing area. Independent samples t-test was performed to compare mean age of patients in urban and sub-urban areas. Multiple Logistic Regression model was applied to examine the association of study variables with disease outcome.ResultsOverall, most patients resided in the urban settings (73%). Mean age of patients was significantly lower in sub-urban areas compared to their counterparts in urban settings (49 ± 23.1 years versus 53 ± 21.1 years, P < 0.001). Positive PCR test results were more common in urban areas (48.5% versus 41.3%, P < 0.001). Yet, sub-urban settings had higher rates of positive chest CT scan reports (62.8% versus 53.4%, P < 0.001). After accounting for age and sex covariates, residing in urban areas was associated with higher likelihood of being admitted to an ICU (OR = 1.27, CI: 1.240-1.305). Yet, a greater vulnerability to fatal outcome of COVID-19 infection was shown in patients living in sub-urban areas (OR = 1.13, CI: 1.105-1.175).ConclusionsThis study revealed a clear disparity in the health outcome of patients infected with COVID-19 between urban and sub-urban areas.