Seroprevalence of SARS-CoV-2 specific IgG antibodies among eye care workers in South India

PurposeHealth care workers are at higher risk of acquiring the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. This study aims to understand the seroprevalence of anti-SARS-CoV-2 IgG antibody among the eye care workers in South India.MethodsThe participants included eye care workers from the nine eye care centres. All the participants were interviewed with a questionnaire to obtain essential information about socio-demographics, past contact with COVID-19 patients and additional information as recommended by Indian Council of Medical Research, India. Serum samples were tested for anti-SARS-CoV-2 IgG antibodies by ELISA.ResultsA total of 1313 workers were included and 207 (15.8%) were positive for the SARS-CoV-2 IgG antibody. The seropositivity was higher in the moderate risk group (19.5%) followed by low (18.6%) and high risk (13.7%) groups. The seropositivity was significantly higher among i) day scholars compared to hostellers (OR - 2.22, 1.56 to 3.15, P ​< ​0.0001), ii) individuals with history of flu-like illness (4.57, 3.08–6.78, P ​< ​0.001) or who were symptomatic or in contact with COVID 19 positive cases (2.2, 1.02–4.75, P – 0.043) and iii) individuals with history of systemic illness (2.11, 1.39–3.21, P ​< ​0.001). Individuals (11.97%) who had no history of contact or any illness were also seropositive.ConclusionsThe effectiveness of the protective measures taken against COVID infection was evident from the lower percentage of seropositivity in the high risk group. The study highlighted the need to create awareness among individuals to follow strict safety measures even in non-work hours and also in social circles.     

Plateletpheresis donor deferral patterns at a tertiary care hospital in North India: A need for rethink of haemoglobin cutoff

IntroductionThe donor deferral criteria for blood or apheresis donations are established for two main reasons: (i) to ensure the safety of the blood donor (non-maleficence); (ii) to obtain safe blood of standard quality that has therapeutic benefit for the patient (beneficence). This study was planned to assess the various causes and patterns of plateletpheresis donor deferral in our hospital and to subsequently assess whether any evidence based changes can be done in the current plateletpheresis donor deferral criteria in India to maximize the platelet donor pool without compromising donor safety.Material and methodsThe present study was conducted from May 2021 till June 2022 in the department of transfusion medicine of a tertiary care hospital in North India. The first part of the study was conducted from May 2021 till March 2022 to assess the various causes of donor deferral by analysing the plateletpheresis donor deferral data during the corresponding period. The second part of the study was conducted from April 2022 till June 2022, to assess: (i) average decrease in haemoglobin after plateletpheresis procedure; (ii) red blood cell loss during plateletpheresis procedure; (iii) to determine whether any correlation exists between donor haemoglobin and platelet yield.ResultsDuring the study period, a total of 260 donors were screened for plateletpheresis, out of which 221 (85%) donors were accepted and 39 (15%) donors were deferred for various reasons. Out of the 39 deferred donors, 33 (84.6%) were temporary deferrals, while 6 (15.4%) were permanent deferrals. Low haemoglobin (Hb < 12.5 g/dl) was a cause of deferral in 12.8% (n = 5) of the deferred donors. 192 (73.9%) out of the 260 donors were replacement donors. The calculated mean decrease in haemoglobin as a result of plateletpheresis procedure was 0.4 g/dl. No correlation was seen between donor pre-donation haemoglobin and platelet yield (p = 0.86, r = 0.06, R² = 0.003). The calculated mean red cell loss as a result of plateletpheresis procedure was 28 ml.ConclusionLow haemoglobin (<12.5 g/dl) is a significant cause of temporary plateletpheresis donor deferral in India. In view of the advancement in plateletpheresis technology, which has resulted in minimal red cell loss with the current generation apheresis devices, haemoglobin cutoff of 12.5 g/dl needs to be reconsidered. Perhaps, after performing a multi-centric trial, a consenscus can be reached for revision of haemoglobin cutoff for plateletpheresis donations.     

Seroprevalence of SARS-CoV-2 in blood donors from the Lodi Red Zone and adjacent Lodi metropolitan and suburban area

ObjectivesTo define the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in blood donors (referred to the first lockdown area (Lodi Red-Zone) of the Lombardy region and in a contiguous area that was not included in the first lockdown); to define the agreement between a commercial serological assay and a reference microneutralization assay; and to evaluate the persistence of SARS-CoV-2 neutralizing antibodies in a cohort of blood donors.MethodsBlood donors referred to the first lockdown area in Lombardy Region and the neighbouring area were analysed for SARS-CoV-2 IgG-specific antibodies during the period 18 March to 24 June 2020. Serum samples were analysed using both a chemiluminescent immunoassay (LIAISON® SARS-CoV-2 S1/S2 IgG, DiaSorin) for the quantitative characterization of SARS-CoV-2 anti-S1 and anti-S2 IgG antibodies and a neutralizing antibodies (NT-Abs) assay.ResultsIn the period from 18 March to 24 June, 1922 blood donors were tested for the presence of SARS-CoV-2 IgG showing a prevalence of 378/1922 (19.7%). A subgroup of 1139 blood donors were tested in parallel with a SARS-CoV-2 IgG assay and a microneutralization assay showing a prevalence of 22.2% and 21.6%, respectively. SARS-CoV-2 IgG quantification was correlated with NT-Abs titres. In 78.2% of participants the NT-Abs titre was maintained, but in 15.8% it decreased by one four-fold dilution and in 6.0% it increased by one four-fold dilution.ConclusionsThe duration of immunity of SARS-CoV-2 is crucial for the course of the pandemic and for this reason the monitoring of NT Abs is important. Despite a stable NT-Abs titre being observed in the majority of blood donors, our findings need to be validated in a long-term period of follow up.     

A cross-sectional study of SARS-CoV-2 seroprevalence among asymptomatic healthcare workers in a tertiary healthcare centre: Assessing the impact of PPE guidelines

PurposeThe present study estimates the seroprevalence of SARS-COV-2 among asymptomatic HCWs and assess the impact of various categories of PPE.MethodsA cross-sectional study of asymptomatic HCW using different levels of PPE as per their risk profile was undertaken between 18th and 24th September 2020. Participant demographics and other relevant details including the levels of PPE used were recorded using a customized questionnaire. IgG antibodies against SARS-COV-2 were detected by chemiluminescence method & used as a surrogate marker for incomplete protection.ResultsOut of 1033 HCWs tested, overall SARS-COV-2 sero-prevalence was 25.8%. Univariate and multivariate analysis both demonstrated that ancillary workers including security staff (OR 5.589, P ​< ​0.001) and sanitary workers (OR 3.946, P ​< ​0.001) were at significantly higher risk of seropositivity irrespective of the PPE used as per guidelines, whereas doctors were at significantly lower risk of seropositivity (OR 0.307, P ​= ​0.005). Staff working in office areas was associated with reduced risk of seropositivity (OR 0.21, P ​= ​0.045).ConclusionsWe document high seroprevalence of SARS-COV-2 antibodies in asymptomatic HCWs. Doctors who are at the highest risk had the lowest seropositivity and seroprevalence among office staff having a risk level comparable to the general community was lower than that reported in general population, supporting the efficacy of PPE practices as per guidelines in these groups. In contrast, much higher rates of seropositivity were seen among ancillary workers despite the availability of adequate PPE. Active screening, proper PPE use as per guidelines, and regular infection control trainings including Covid appropriate behaviour are therefore essential to contain COVID-19 spread among HCW & preventing them to transfer infection to the patients.     

Differences in environmental stability among SARS-CoV-2 variants of concern: both omicron BA.1 and BA.2 have higher stability

ObjectivesThe increased infectivity and transmissibility of SARS-CoV-2 variants of concern (VOCs) could cause significant human and economic damage. Hence, understanding their characteristics is crucial to control infection. We evaluated the environmental stability of the Wuhan strain and all VOCs (Alpha, Beta, Gamma, Delta, Omicron BA.1, and Omicron BA.2 variants) on plastic and human skin surfaces and their disinfection efficacy.MethodsTo evaluate environmental stability, residual virus titres on plastic and human skin surfaces were measured over time. Their survival time and half-life were calculated using regression analysis. The effectiveness of ethanol-based disinfectants at different concentrations was determined by in vitro and ex vivo evaluations.ResultsOn plastic and skin surfaces, the Alpha, Beta, Delta, and Omicron variants exhibited approximately two-fold longer survival times than the Wuhan strain; the Omicron variants had the longest survival time. The median survival times of the Wuhan strain and the Alpha, Beta, Gamma, Delta, and Omicron (BA.1 and BA.2) variants on human skin surface were 8.6, 19.6, 19.1, 11.0, 16.8, 21.1, and 22.5 h, respectively. The in vitro evaluation showed that the Wuhan strain and the Alpha, Beta, Gamma, Delta, and Omicron (BA.1 and BA.2) variants were completely inactivated within 15 s by 32.5%, 35%, 35%, 32.5%, 35%, 40%, and 40% ethanol, respectively. However, all viruses on human skin were completely inactivated by exposure to 35% ethanol for 15 s.ConclusionsSARS-CoV-2 VOCs, especially the Omicron variants, have higher environmental stability than the Wuhan strain, increasing their transmission risk and contributing to their spread.     

Impact of dexamethasone on SARS-CoV-2 concentration kinetics and antibody response in hospitalized COVID-19 patients: results from a prospective observational study

ObjectivesDexamethasone has become the standard of care for severe coronavirus disease 2019 (COVID-19), but its virological impact is poorly understood. The objectives of this work were to characterize the kinetics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) concentration in the upper respiratory tract (URT) and the antibody response in patients with (D⁺) and without (D^–) dexamethasone treatment.MethodsData and biosamples from hospitalized patients with severe COVID-19, enrolled between 4th March and 11th December 2020 in a prospective observational study, were analysed. SARS-CoV-2 virus concentration in serial URT samples was measured using RT-PCR. SARS-CoV-2-specific immunoglobulins A and G (IgA and IgG) were measured in serum samples using S1-ELISA.ResultsWe compared 101 immunocompetent patients who received dexamethasone (according to the inclusion criteria and dosage determined in the RECOVERY trial) to 93 immunocompetent patients with comparable disease severity from the first months of the pandemic, who had not been treated with dexamethasone or other glucocorticoids. We found no inter-group differences in virus concentration kinetics, duration of presence of viral loads >10⁶ viral copies/mL (D⁺ median 17 days (IQR 13–24), D^– 19 days (IQR 13–29)), or time from symptom onset until seroconversion (IgA: D⁺ median 11.5 days (IQR 11–12), D^– 14 days (IQR 11.5–15.75); IgG: D⁺ 13 days (IQR 12–14.5), D^– 12 days (IQR 11–15)).ConclusionDexamethasone does not appear to lead to a change in virus clearance or a delay in antibody response in immunocompetent patients hospitalized with severe COVID-19.     

Assessment of Her‐2/neu status using immunocytochemistry and fluorescence in situ hybridization on fine‐needle aspiration cytology smears: Experience from a tertiary care centre in India

Breast carcinoma shows amplification/overexpression of Her‐2/neu in ～20–30% of cases. The determination of Her‐2/neu expression accurately is vital in clinical practice as it has significant predictive value and eligibility for anti Her‐2/neu therapy. Amplification and overexpression of Her‐2/neu gene is traditionally identified by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) on tissue sections; only a few studies have evaluated feasibility of these techniques on cytological smears. One hundred cases of breast cancer with fine‐needle aspiration cytology (FNAC) samples and corresponding surgically resected specimen were selected. Immunocytochemistry (ICC) and FISH for Her‐2/neu was done on FNA smears, whereas IHC was performed on corresponding tissue sections. Diagnostic accuracy of ICC was 99% when compared with IHC. Comparison of FISH results with IHC showed 100% concordance. Unlike many centers in West, FNAC is still routinely performed in developing countries like India where vast majority of breast cancer cases present as palpable lumps. The high rates of accuracy of ICC and FISH for Her‐2/neu detection can make FNAC a relevant first line of investigation as a cost effective model with a rapid turn‐around time, providing complete information necessary for initial management of breast cancer patients. Diagn. Cytopathol. 2014;42:726–731. © 2013 Wiley Periodicals, Inc.     

Prevalence and trends in the antimicrobial susceptibility pattern of <Emphasis Type="Italic">Salmonella enterica</Emphasis> serovars Typhi and Paratyphi A among children in a pediatric tertiary care hospital in South India over a period of ten years: a retrospective study

The aim of this study was to determine the prevalence and trends in the antimicrobial resistance of typhoidal salmonellae in children and adolescents at a pediatric tertiary care hospital in South India. Typhoidal salmonellae were isolated from 483 of the 77,713 blood cultures received during the ten-year study period (2007–2016). Isolates were speciated by conventional biochemical reactions and serotyping. Antimicrobial susceptibility testing was performed and interpreted according to the British Society for Antimicrobial Chemotherapy (BSAC)/European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. The overall blood culture isolation rates of Salmonella enterica serovars Typhi and Paratyphi A in children were 0.5% (408 cases) and 0.1% (73 cases), respectively, with the highest isolation rates in school [299 (61.9%)] and preschool children [113 (23.4%)]. A decreasing prevalence of enteric fever was seen from 2012 to 2015, with a sudden surge in 2016. From 2011 onwards, a high fluoroquinolone resistance (90–100%) was observed. Multidrug resistance was observed in only four (0.9%) S. Typhi isolates. 100% susceptibility to third-generation cephalosporins and azithromycin was noted. Enteric fever as seen in a pediatric tertiary care hospital in India affects children and adolescents of all age groups, with greater isolation rates in school children, followed by those in preschool years, calling for targeted interventions against these age groups. The study findings support the use of third-generation cephalosporins and azithromycin as first-line therapy and ampicillin and co-trimoxazole as step-down therapy in pediatric enteric fever. However, continued local surveillance should be done to detect antimicrobial resistance trends to optimize treatment.