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1.
Transfus Clin Biol ; 2022.
Article in English | ScienceDirect | ID: covidwho-2031716
2.
Annals of Nutrition & Metabolism ; 78:55, 2022.
Article in English | ProQuest Central | ID: covidwho-2011351

ABSTRACT

Introduction: Age, chronic diseases, and body mass index (BMI) are associated with differences in immune responses to vaccines and are significant suppressors of COVID-19 vaccine immunogenicity. However, knowledge of the relationship between healthy dietary patterns, such as the Mediterranean diet (MD), and the humoral response to COVID-19 vaccine is still scarce. Objectives: Given the biological capacity supporting the beneficial effects of the MD on the immune system, we longitudinally evaluated the association between immune activity, after two doses of BNT162b2 vaccine, on age, BMI, and chronic conditions, in Spanish elderly. Methods: Immunogenicity was analyzed in a convenience sample of 106 institutionalized elderly volunteers (65.1% females, 84.3 ± 7.6 years, 27.2 ± 5.2 kg/m2). Subjects received the first dose of BNT162b2 vaccine and a booster dose 21 days later. Blood and nasopharyngeal swab samples were taken at baseline and 20 days after each vaccine dose. Quantitative measurements S1 SARS-CoV-2 spike protein were determined by a chemiluminescent immunoassay. The presence of SARS-CoV-2 was determined by RT-PCR assay. Adherence to the MD was assessed by Trichopoulou's score, chronic diseases by medical records. The study was approved by ECRmp the University Hospital Valladolid (Spain) No.21-2413. Results: Trichopoulou's score was 10.1 ± 1.8. The correlation coefficient between total anti-SARS-CoV-2 IgG antibody titer and BMI (Spearman rho= 0.05, p-value= 0.64), age (Spearman rho= -0.10, p-value= 0.31), both were extremely weak. The comparison between the number of chronic conditions was not significant for both antibody titer after the 1st dose (p-value Kruskal Wallis test = 0.63) and antibody titer after the 2nd dose (p-value Kruskal Wallis test = 0.51). No volunteer showed a PCR+. Conclusions: SARS-CoV-2 antispike IgG antibodies titer was independent of the characteristics (age, BMI, chronic diseases) of the elderly. Better adherence to the MD (≥8) may be associated with enhanced immunogenicity.

3.
PLoS One ; 17(8), 2022.
Article in English | ProQuest Central | ID: covidwho-2002309

ABSTRACT

We conducted a seroprevalence survey to estimate the true number of infections with SARS-CoV-2, the virus that causes COVID-19, in King County as of August 2020 by measuring the proportion of residents from who had antibodies against the virus. Participants from 727 households took part in a cross-sectional address-based household survey with random and non-random samples and provided dried blood spots that were tested for total antibody against the viral nucleocapsid protein, with confirmatory testing for immunoglobulin G against the spike protein. The data were weighted to match King County’s population based on sex, age group, income, race, and Hispanic status. After weighting and accounting for the accuracy of the tests, our best overall estimate of anti-SARS-CoV-2 seroprevalence in King County as of August 2020 is 3.9% (95% confidence interval (CI) 2.4%-6.0%) with an effective sample size of 589. Comparing seroprevalence with positive test reports, our survey suggests that viral testing underestimated incidence by a factor of about five and suggests that the proportion of cases that were serious (based on hospitalization) or fatal was 2.4% and 0.8%, respectively. Prevalence varied by subgroup;households reporting incomes at or below $100,000 in 2019 had nearly five times higher estimated antibody prevalence than those with incomes above $100,000. Those reporting non-White/non-Asian race had roughly seven times higher estimated antibody prevalence than those reporting White race. This survey was noteworthy for including people of all ages;among all age groups, the weighted estimate of prevalence was highest in older teens and young adults and lowest in young children, although these differences were not statistically significant.

4.
Front Microbiol ; 13: 922042, 2022.
Article in English | MEDLINE | ID: covidwho-1997466

ABSTRACT

Background: The mortality rate due to COVID-19 in kidney transplant recipients (KTRs) is 16.8 to 32%. Vaccination against COVID-19 is expected to contribute to the prevention of infection, severe disease, and mortality; however, it has been reported that the humoral response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine in KTRs is poor. Vaccination strategies against COVID-19 vary from country to country, and in Japan, the third dose is given 6 months after the second dose. Few studies have evaluated long-term humoral responses after the second dose of SARS-CoV-2 mRNA vaccine. In addition, the superiority of BNT162b2 vaccine and mRNA-1,273 vaccine in KTRs regarding humoral response is controversial. Methods: Ninety-four KTRs were administered a second dose of the BNT162b2 or mRNA-1,273 vaccines, and anti-spike (anti-S) and anti-nucleocapsid (anti-N) SARS-CoV-2 antibody levels were measured 5 months (149.2 ± 45.5 days) later. The cutoff value of anti-S antibodies was defined ≥50 AU/ml and 1.4 Index for anti-N antibodies. The primary outcome was the rate of seropositivity, and factors associated with an appropriate humoral response were assessed by univariate and multivariate analysis. Results: Of 94 KTRs, only 45 (47.9%) patients were positive for anti-S antibodies. The median anti-S SARS-CoV-2 IgG antibody titers was 35.3 (Interquartile range 3.8 to 159.7). Anti-N SARS-CoV-2 IgG antibodies in all patients were < 1.4 Index. Response to SARS-CoV-2 mRNA vaccines were 43.2 and 65% for BNT162b2 and mRNA-1,273, respectively (p = 0.152). In comparison with high-dose, low-dose of mycophenolic acid was a robust factor associated with an adequate humoral response. Conclusion: The long-term humoral response after a second dose of SARS-CoV-2 mRNA vaccine in Japanese KTRs was poor. In comparison with high-dose, low-dose mycophenolic acid was related to an appropriate humoral response. Five months is too long to wait for a 3rd dose after 2nd dose of SARS-CoV-2 vaccine in KTRs. In this cohort, there was no statistical difference in humoral response to the BNT162b2 and mRNA-1,273 vaccines. Additional large observational studies and meta-analyses are needed to clarify the factors related to an appropriate humoral immune response to COVID-19 vaccination.

6.
Intern Med ; 2022 Aug 10.
Article in English | MEDLINE | ID: covidwho-1978928

ABSTRACT

Objective To examine the continuation of antibody prevalence status after 12 months and background factors in antibody-positive subjects following asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods We initially determined the SARS-CoV-2 anti-nucleocapsid protein immunoglobulin G (anti-N IgG) antibody prevalence in 1603 patients, doctors, and nurses at 65 medical institutions in Kanagawa Prefecture, Japan. We then obtained consent from 33 of the 39 subjects who tested positive and performed follow-up for 12 months. Results Follow-up for up to 12 months showed that a long-term response of the anti-N IgG antibody could be detected in 6 of the 33 participants (18.2%). The proportions with hypertension, using an angiotensin-receptor blocker, and without a drinking habit were higher among the participants with a long-term anti-N IgG antibody response for up to 12 months than among those without a long-term antibody response. Conclusions The proportion of individuals with subclinical COVID-19 who continuously had a positive result for the anti-N IgG antibody at 12 months was low.

7.
Fukushima J Med Sci ; 68(1): 67-70, 2022 Apr 08.
Article in English | MEDLINE | ID: covidwho-1975228

ABSTRACT

This study investigated the immune response and outcome of BNT162b2 vaccination among 12 staff at a hospital in Fukushima, Japan. Blood samples were collected from participants before their first vaccination, with subsequent sampling performed during the participants' work days for six weeks thereafter. Antibody titers peaked 6-13 days after the second vaccination (days 27-34 after the first), followed by a steady decrease. Six males had significantly lower peak antibody titers than six females (p = 0.016 with t-test); the older six (median age 53 years) had lower antibody titers than the younger six (median age 35 years) but without statistical significance (p value=0.24 with t-test).


Subject(s)
Antibodies, Viral , BNT162 Vaccine , COVID-19 , Immunoglobulin G , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Adult , Antibodies, Viral/immunology , BNT162 Vaccine/administration & dosage , BNT162 Vaccine/immunology , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Female , Humans , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
8.
Infect Drug Resist ; 15: 3791-3800, 2022.
Article in English | MEDLINE | ID: covidwho-1957124

ABSTRACT

Background: SARS-CoV-2 pandemic continues to threaten the human population with millions of infections and deaths worldwide. Vaccination campaigns undertaken by several countries have resulted in a notable decrease in hospitalization and deaths. However, with the emergence of new virus variants, it is critical to determine the longevity and the protection efficiency provided by the current authorized vaccines. Aim: The aims of this study are to provide data about the magnitude of immune responses in individuals fully vaccinated against COVID-19 in Riyadh province of Saudi Arabia. Also, to evaluate the continuity of specific IgG levels and compare the titers in individuals who have been received two doses of the matched and mixed vaccines, including Pfizer and AstraZeneca against SARS-CoV-2 during the period of three to six months. Moreover, we analyze the current state of immune response in terms of antibody responses in thepopulation postvaccination using homogenous or hetrogenous vaccine regimen. Methods: A total of 141 healthy volunteers were recruited to our study; blood (n=63) and the saliva samples (n=78) and were collected from fully vaccinated individuals in Riyadh city. We employed a specific ELISA assay in plasma and saliva of fully vaccinated individuals. Results: IgG levels varied with age groups with the highest concentration in the age group 19-29 years, but the age group (≥50) had the lowest IgG concentration. The IgG levels in both serum and saliva were higher after three months and start to wane after six months. Individuals who received mixed types of vaccines had significantly better response than Pfizer vaccine alone. Conclusion: The current study investigates the status of humoral responses in different age groups, in terms of antibody measurements. These data will help to evaluate the need for further COVID-19 vaccine doses and to what extent a two-dose regimen will protect vaccinated individuals.

9.
Biosens Bioelectron ; 215: 114563, 2022 Jul 14.
Article in English | MEDLINE | ID: covidwho-1936099

ABSTRACT

Ultrasensitive, specific, and early identification of Coronavirus Disease (2019) (COVID-19) infection is critical to control virus spread and remains a global public health problem. Herein, we present a novel solid-state electrochemiluminescence (ECL) platform targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody with rapidity and ultrahigh sensitivity, in which a bipolar silica nanochannel array (bp-SNA) is fabricated on indium tin oxide (ITO) electrode for the first time to stably confine the ECL probe of tris(2,2'-bipyridyl) ruthenium (Ru(bpy)32+) under dual electrostatic force. The bp-SNA consists of tightly packed bilayer silica nanochannel array (SNA) with asymmetric surface charges, namely an inner negatively charged SNA (n-SNA) and an outer positively charged SNA (p-SNA), serving as an "electrostatic lock" to enrich and stabilize the cationic Ru(bpy)32+ probe without leakage from the electrode surface. The detection of SARS-CoV-2 IgG antibody could be realized via immobilization of SARS-CoV-2 spike protein on the utmost of Ru(bpy)32+-confined solid-state ECL platform (Ru@bp-SNA). Upon the capture of target SARS-CoV-2 IgG by immune recognition, the formed immunocomplex will block the nanochannel, leading to the hindered diffusion of the co-reactant (tri-n-propylamine, TPrA) and further producing a decreased ECL signal. The developed solid-stated ECL immunosensor is able to determine SARS-CoV-2 IgG with a wide linear range (5 pg mL-1 to 1 µg mL-1), a low limit-of-detection (2.9 pg mL-1), and a short incubation time (30 min). Furthermore, accurate analysis of SARS-CoV-2 IgG in real serum samples is also obtained by the sensor.

10.
Oman J Ophthalmol ; 15(2): 234-236, 2022.
Article in English | MEDLINE | ID: covidwho-1934429

ABSTRACT

Thromboembolic complications are being increasingly reported in patients with COVID-19 due to the associated hypercoagulability and are an important cause for morbidity and mortality. Retinal vascular occlusions especially arterial occlusions are one of the gravest ocular complications reported. This complication may occur in severe cases with cytokine storm or even in mild or asymptomatic patients and presentation can be anytime from few days to weeks after the onset of symptoms. Ophthalmologists should be aware of this new etiology when dealing with patients having features of retinal vascular occlusions and should investigate for the same in this pandemic situation. Although reverse transcriptase polymerase chain reaction is the diagnostic test for COVID-19, serological assays have a role in patients with delayed presentation. We describe the clinical features and multimodal imaging findings in a patient who presented with features of central retinal artery occlusion with cilioretinal artery sparing wherein his ophthalmic condition led to the diagnosis of previously undetected COVID-19 through serology. To the best of our knowledge, this is the first documentation of a case of isolated central retinal artery occlusion leading to a retrospective diagnosis of COVID-19.

11.
Immune Netw ; 22(3): e24, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1924454

ABSTRACT

Coronavirus disease 2019 (COVID-19) vaccination in immunocompromised, especially transplant recipients, may induce a weaker immune response. But there are limited data on the immune response after COVID-19 vaccination in liver transplant (LT) recipients, especially on the comparison of Ab responses after different vaccine platforms between mRNA and adenoviral vector vaccines. Thus, we conducted a prospective study on LT recipients who received two doses of the ChAdOx1 nCoV-19 (ChAdOx1), mRNA-1273, or BNT162b2 vaccines compared with healthy healthcare workers (HCWs). SARS-CoV-2 S1-specific IgG Ab titers were measured using ELISA. Overall, 89 LT recipients (ChAdOx1, n=16 [18%]) or mRNA vaccines (mRNA-1273 vaccine, n=23 [26%]; BNT162b2 vaccine, n=50 [56%]) received 3 different vaccines. Of them, 16 (18%) had a positive Ab response after one dose of COVID-19 vaccine and 62 (73%) after 2 doses. However, the median Ab titer after two doses of mRNA vaccines was significantly higher (44.6 IU/ml) than after two doses of ChAdOx1 (19.2 IU/ml, p=0.04). The longer time interval from transplantation was significantly associated with high Ab titers after two doses of vaccine (p=0.003). However, mycophenolic acid use was not associated with Ab titers (p=0.53). In conclusion, about 3-quarters of LT recipients had a positive Ab response after 2 doses of vaccine, and the mRNA vaccines induced higher Ab responses than the ChAdOx1 vaccine.

12.
Clinical Kidney Journal ; : 5, 2022.
Article in English | Web of Science | ID: covidwho-1895808

ABSTRACT

Safe and timely discontinuation of quarantine of in-center hemodialysis (HD) patients with a previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a challenging issue for the nephrological community because current guidelines for ending isolation do not mention dialysis patients. To prevent potentially fatal outbreaks of coronavirus disease 2019 (COVID-19), a cautionary approach has been adopted by most dialysis units. The criteria for ending the isolation in the HD population generally coincide with those recommended for immunocompromised people. Thus, a test-based strategy relying on two consecutive negative reverse transcriptase-polymerase chain reaction (RT-PCR) nasopharyngeal swabs has been adopted to terminate quarantine. This strategy has the disadvantage of prolonging isolation as RT-PCR positivity does not equate to SARS-CoV-2 infectivity. Consequentially, prolonged positivity of SARS-CoV-2 results in excessive workload for the HD staff who must face an increasing number of COVID-19 patients requiring isolation. This condition leads also to serious implications for the patients and their households including work productivity loss, postponement of health-care appointments and an increased risk of COVID-19 reinfection. To counteract this problem, other diagnostic tests should be used to provide the best care to HD patients. Recent results seem to encourage the use of RT-PCR cycle threshold (Ct) values and rapid antigen tests given their better correlation with cell culture for SARS-CoV-2 than RT-PCR testing. Here, we provide an overview of the current scientific evidence on the tests used to verify the infectiousness of the virus in order to stimulate the nephrological community to adopt a streamlined and pragmatic procedure to end isolation in COVID-19 patients on HD.

13.
J Infect ; 85(3): 306-317, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1895207

ABSTRACT

OBJECTIVES: We aimed to evaluate the safety and optimal dose of a novel inactivated whole-virus adjuvanted vaccine against SARS-CoV-2: VLA2001. METHODS: We conducted an open-label, dose-escalation study followed by a double-blind randomized trial using low, medium and high doses of VLA2001 (1:1:1). The primary safety outcome was the frequency and severity of solicited local and systemic reactions within 7 days after vaccination. The primary immunogenicity outcome was the geometric mean titre (GMT) of neutralizing antibodies against SARS-CoV-2 two weeks after the second vaccination. The study is registered as NCT04671017. RESULTS: Between December 16, 2020, and June 3, 2021, 153 healthy adults aged 18-55 years were recruited in the UK. Overall, 81.7% of the participants reported a solicited AE, with injection site tenderness (58.2%) and headache (46.4%) being the most frequent. Only 2 participants reported a severe solicited event. Up to day 106, 131 (85.6%) participants had reported any AE. All observed incidents were transient and non-life threatening in nature. Immunogenicity measured at 2 weeks after completion of the two-dose priming schedule, showed significantly higher GMTs of SARS-CoV-2 neutralizing antibody titres in the highest dose group (GMT 545.6; 95% CI: 428.1, 695.4) which were similar to a panel of convalescent sera (GMT 526.9; 95% CI: 336.5, 825.1). Seroconversion rates of neutralizing antibodies were also significantly higher in the high-dose group (>90%) compared to the other dose groups. In the high dose group, antigen-specific IFN-γ expressing T-cells reactive against the S, M and N proteins were observed in 76, 36 and 49%, respectively. CONCLUSIONS: VLA2001 was well tolerated in all tested dose groups, and no safety signal of concern was identified. The highest dose group showed statistically significantly stronger immunogenicity with similar tolerability and safety, and was selected for phase 3 clinical development.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19/therapy , COVID-19 Vaccines/adverse effects , Double-Blind Method , Humans , Immunization, Passive , Immunogenicity, Vaccine , SARS-CoV-2
14.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(1): 36-40, 2022 Feb 23.
Article in Chinese | MEDLINE | ID: covidwho-1893447

ABSTRACT

OBJECTIVE: To evaluate the diagnostic efficiency of four anti-cysticercus IgG, IgG4 or IgM antibody test kits (enzyme-linked immunosorbent assay, ELISA) by different manufacturers, so as to provide insights into the epidemiological investigation and clinical detection of cysticercosis. METHODS: Forty serum samples from cerebral cysticercosis patients, 100 serum samples from healthy volunteers, 30 serum samples from paragonimiasis skrjabini patients, 17 serum samples from cystic echinococcosis and 19 serum samples from subcutaneous or cerebral sparganosis patients were collected and detected using anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) and the anti-cysticercus IgG antibody test kit (brand B). The sensitivity, specificity and false negative rate of the four kits for detection of cysticercosis were estimated. RESULTS: The anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) showed 95.00% (38/40), 87.50% (35/40), 7.50% (3/40) sensitivities and 98.00% (98/100), 100.00% (100/100) and 100.00% (100/100) for detection of cysticercosis, while the anti-cysticercus IgG antibody test kit (brand B) presented a 75.00% (30/40) sensitivity and 100.00% (100/100) specificity for detection of cysticercosis. The sensitivity for detection of cysticercosis was significantly higher by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 6.28, P < 0.05); however, no significant difference was seen in the specificity by two kits (χ2 = 2.01, P > 0.05). The four ELISA kits showed overall false positive rates of 37.88% (25/66), 22.73% (15/66), 62.12% (41/66) and 15.15% (10/66) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 37.61, P < 0.05), and the anti-cysticercus IgG antibody test kit (brand A) presented the highest overall false positive rate for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 7.56, P' < 0.008), while a higher overall false positive rate was seen for detection of paragonimiasis, echinococcosis and sparganosis by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 8.75, P' < 0.008). The four ELISA kits showed false positive rates of 40.00% (12/30), 16.67% (5/30), 76.67% (23/30) and 13.33% (4/30) for detection of paragonimiasis (χ2 = 32.88, P < 0.05) and 21.05% (4/19), 26.32% (5/19), 73.68% (14/19) and 15.79% (3/19) for detection of sparganosis (χ2 = 19.97, P < 0.05), and the highest false positive rates were found by the anti-cysticercus IgM antibody test kit (brand A) for detection of paragonimiasis and sparganosis (all P' < 0.008). However, the four ELISA kits showed comparable false positive rates of 52.94% (9/17), 29.41% (5/17), 23.53% (4/17) and 17.65% (3/17) for detection of echinococcosis (χ2 = 8.24, P > 0.05). In addition, the anti-cysticercus IgM anti-body test kit (brand A) showed false positive rates of 76.67% (23/30), 23.53% (4/17) and 73.68% (14/19) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 14.537, P < 0.05), with the lowest false positive rate seen for detection of echinococcosis (χ2 = 14.537, P' < 0.014), while no significant differences were seen in the false positive rate for detection of paragonimiasis, echinococcosis and sparganosis by other three ELISA kits (all P > 0.05). CONCLUSIONS: The four anti-cysticercus IgG, IgG4 or IgM antibody test kits exhibit various efficiencies for serodiagnosis of cysticercosis. The anti-cysticercus IgG antibody test kit (brand A) has a high sensitivity for serodiagnosis of cysticercosis; however, it still needs to solve the problems of cross-reaction with other parasitic diseases and stability.


Subject(s)
Cysticercosis , Cysticercus , Animals , Antibodies, Helminth , Cysticercosis/diagnosis , Enzyme-Linked Immunosorbent Assay , Humans , Reagent Kits, Diagnostic , Sensitivity and Specificity , Serologic Tests
15.
Laboratoriumsmedizin ; 46(3):171-177, 2022.
Article in German | ProQuest Central | ID: covidwho-1892382

ABSTRACT

Third dose of SARS-CoV-2 vaccination was started from December 1, 2021 in Japan. However, data on the precise analysis of the side effects after third vaccination, remain scarce. Here, we examined the side effects and the levels of SARS-CoV-2 IgG antibody in healthy volunteers who underwent BNT162b2 vaccination.Forty-one healthy volunteers were assessed for the side effects of the vaccination for the third dose, and samples were used for the measurement of SARS-CoV-2 IgG antibody with chemiluminescent assays against the Receptor Binding Domain (RBD) of the virus.We analyzed the humoral responses and found that the IgG levels showed clear declining trends with age. Commonly reported side effects in the participants after the third dose were similar to those in second dose, such as, generalized weakness/fatigue (65.9%), headache (58.5%), and sore arm/pain (87.8%). The frequency of the fever was slightly less (39.0%), compared to the second dose (57.5%), but localized symptoms, such as itching (14.6%) and lymphadenopathy (14.6%) were not negligible, which were not seen at the second dose. The number of side effects were tended to be decreased with age.The production of IgG after the third doses of BNT162b2 vaccination decreases age-dependently. The number of side effects were tended to be decreased with age. The high frequencies of generalized weakness/fatigue, fever, and sore arm/pain were not negligible, after the third dose.

16.
Int J Infect Dis ; 119: 18-20, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1889466

ABSTRACT

We present a case of a 58-year-old Japanese man with a history of 2 previous COVID-19 infections, who received 2 doses of mRNA-1273 vaccine. We are not aware of any previous study regarding antibody tendency after 2 infections and 2 vaccinations. We evaluated his IgG titer of antispike protein and neutralizing activity from the first infection before and after 2 doses of vaccine. Both antispike IgG titer and neutralizing activity showed a tendency to decline almost 1 year after initial infection; they rapidly increased after the first vaccination, and they remained high after the second vaccination. Although this is a single case report, it seems to have generalizability because the findings are consistent with previous reports regarding single infections or 3 doses of vaccination. Our findings suggest that a single booster shot may provide sufficient protection and aid the understanding of immunologic responses of vaccination in patients with COVID-19 with history of re-infection.


Subject(s)
COVID-19 , 2019-nCoV Vaccine mRNA-1273 , Antibodies, Neutralizing , Antibodies, Viral , Antibody Formation , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , Male , Middle Aged , Reinfection , SARS-CoV-2 , Vaccination
17.
Nano Res ; 15(6): 5510-5516, 2022.
Article in English | MEDLINE | ID: covidwho-1877966

ABSTRACT

Developing convenient and accurate SARS-CoV-2 antigen test and serology test is crucial in curbing the global COVID-19 pandemic. In this work, we report an improved indium oxide (In2O3) nanoribbon field-effect transistor (FET) biosensor platform detecting both SARS-CoV-2 antigen and antibody. Our FET biosensors, which were fabricated using a scalable and cost-efficient lithography-free process utilizing shadow masks, consist of an In2O3 channel and a newly developed stable enzyme reporter. During the biosensing process, the phosphatase enzymatic reaction generated pH change of the solution, which was then detected and converted to electrical signal by our In2O3 FETs. The biosensors applied phosphatase as enzyme reporter, which has a much better stability than the widely used urease in FET based biosensors. As proof-of-principle studies, we demonstrate the detection of SARS-CoV-2 spike protein in both phosphate-buffered saline (PBS) buffer and universal transport medium (UTM) (limit of detection [LoD]: 100 fg/mL). Following the SARS-CoV-2 antigen tests, we developed and characterized additional sensors aimed at SARS-CoV-2 IgG antibodies, which is important to trace past infection and vaccination. Our spike protein IgG antibody tests exhibit excellent detection limits in both PBS and human whole blood ((LoD): 1 pg/mL). Our biosensors display similar detection performance in different mediums, demonstrating that our biosensor approach is not limited by Debye screening from salts and can selectively detect biomarkers in physiological fluids. The newly selected enzyme for our platform performs much better performance and longer shelf life which will lead our biosensor platform to be capable for real clinical diagnosis usage. Electronic Supplementary Material: Supplementary material (materials and methods for device fabrication, functionalization of In2O3 devices, photographs of the liquid gate measurement setup, mobilities of the nine devices labeled in Fig. 1(b), family curves of I DS-V DS with the liquid gate setup and current change after bubbling the substrate solution (current vs. time curve for S1 antigen detection)) is available in the online version of this article at 10.1007/s12274-022-4190-0.

18.
Chinese General Practice ; 25(14):1741-1748, 2022.
Article in Chinese | Scopus | ID: covidwho-1863322

ABSTRACT

Background: Based on the current prevalence of Coronavirus Disease 2019 (COVID-19), early diagnosis, isolation, and treatment are important methods to prevent and control infectious diseases. The establishment of convenient and efficient immunochromatographic detection techniques is essential for the prevention and control of COVID-19 epidemic. Objective: To establish a method for the detection of SARS-CoV-2 anti-N protein IgG antibody by immun of luorescence chromatography method based on quantum dots labeling technology in August, 2020. In order to determine whether the detected persons had been infected with COVID-19 or been injected with SARS-CoV-2 inactivated vaccine. Methods The prepared rat anti-human secondary antibody and anti-N protein antibody were immobilized on a Nitrocellulose (NC) membrane as detection line (T) and quality control line (C), respectively. Then the SARS-CoV-2 N protein labeled by quantum dots was evenly sprayed on glass fiber, which was assembled, cut and packaged into test strips after drying. The test strips were used to detect the clinical serum of 35 COVID-19 patients and 50 healthy individuals, the results of the initial screening of the ELISA kit were used as a control to calculate the detection specificity and sensitivity of quantum dots fluorescence immunochromatography. The sensitivity of the test strip was detected by using the N protein antibody standard. Results The specificity and sensitivity of the strip were 100.00%, 94.29%, and the susceptibility was 8.53-17.06 ng/ml antibody concentration. Conclusion: The detection of anti-N protein IgG antibody in serum by quantum dots labeling is simple, fast, with strong sensitivity and specificity. Copyright © 2022 by the Chinese General Practice.

19.
Healthcare (Basel) ; 10(5)2022 May 12.
Article in English | MEDLINE | ID: covidwho-1855571

ABSTRACT

Health care workers (HCW) are at high risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The incidence of SARS-CoV-2 infection in HCW has been examined in cross-sectional studies by quantitative polymerase chain reaction (qPCR) tests, which may lead to underestimating exact incidence rates. We thus investigated the incidence of SARS-CoV-2 infection in a group of HCW at a dedicated coronavirus disease 2019 (COVID-19) hospital in a six-month follow-up period. We conducted a prospective cohort study on 109 participants of both sexes working in areas of high, moderate, and low SARS-CoV-2 exposure. qPCR tests in nasopharyngeal swabs and anti-SARS-CoV-2 IgG serum antibodies were assessed at the beginning and six months later. Demographic, clinical, and laboratory parameters were analyzed according to IgG seropositivity by paired Student's T-test or the chi-square test. The incidence rate of SARS-CoV-2 infection was considerably high in our cohort of HCW (58%), among whom 67% were asymptomatic carriers. No baseline risk factors contributed to the infection rate, including the workplace. It is still necessary to increase hospital safety procedures to prevent virus transmissibility from HCW to relatives and non-COVID-19 patients during the upcoming waves of contagion.

20.
Rinsho Ketsueki ; 63(4): 247-253, 2022.
Article in Japanese | MEDLINE | ID: covidwho-1835808

ABSTRACT

This is a prospective study conducted to determine the level of anti-spike IgG to SARS-CoV-2 2-6 weeks following the BNT162b2 vaccination in 125 patients with hematological disorders. Compared with healthy controls, patients with malignant lymphoma had lower rates of seropositivity and lower levels of antibody titer. Furthermore, patients who received rituximab (R)-containing chemotherapy had lower antibody titers than those who were not treated with R or who had completed R-containing chemotherapy more than 9 months earlier. Despite having 71% IgG-seropositivity, patients with multiple myeloma had lower antibody titers than the control group. Furthermore, patients receiving daratumumab-containing chemotherapy had lower antibody titers than those not receiving treatment. Moreover, patients with acute myeloid leukemia or myelodysplastic syndrome had lower antibody titers than the control group. Overall, the number of peripheral blood lymphocytes was significantly correlated with IgG titers, with seropositive patients having more peripheral blood lymphocytes than seronegative patients. Patients with severe immunosuppression, such as those with hematological disorders, often have impaired seroconversion with COVID-19 vaccination that should be taken into consideration by clinicians.


Subject(s)
COVID-19 , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , Prospective Studies , RNA, Messenger , RNA, Viral , SARS-CoV-2 , Vaccination
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