It is currently unknown how Post-COVID-19 Syndrome (PCS) may affect those infected with SARS-CoV-2. This longitudinal study reports on healthcare staff who tested positive for SARS-CoV-2 between March-April 2020 and follows their antibody titres and symptomatology. Over half (n=21/38) had PCS at 7-8 months. There was no statistically significant difference between initial RT-PCR viral titres or serial antibody levels between those who did and did not develop PCS. This study highlights the relative commonality of PCS in healthcare workers and this should be considered in vaccination scheduling and workforce planning to allow adequate frontline staffing numbers.
The COVID-19 pandemic is a serious healthcare challenge, leading to more than 5 million deaths worldwide so far. The rapid advent of modern messenger RNA-and adenovirus DNA vector-based anti-SARS-CoV-2 vaccines has already been associated with a significant reduction in the rate of COVID-19 deaths. 1 Haematological malignancies and/or their treatments are linked to impaired immunocompetence, which has been highlighted by recent reports of severe COVID-19 outcomes 2 and poor responses to SARS-CoV-2 vaccines. 3,4 Interestingly, patients with chronic myeloid leukaemia (CML) on BCR-ABL1 tyrosine kinase inhibitors (TKI) seem to have less severe COVID-19 compared to patients with other haematological cancers. 5 Also, although TKI have been reported to be immunosuppressive, 6,7 two recent prospective studies demonstrated that CML patients on TKI can mount an early immune response after the first dose of BNT162b2 (Pfizer-BioNTech). 8,9 We are conducting a prospective observational study (CML-Co-vax) at our centre, of which the primary objective is the evaluation of the seroconversion rate and the median anti-SARS-CoV-2 receptor binding domain (RBD) antibody level in CML patients on TKI compared to healthy subjects (HS), at early and late time points after the first and the second dose of SARS-CoV-2 vaccines. Patients and HS were assessed serially at baseline (T0), day +21 ± 7 (T1), day +49 ± 7 (T2) after the first dose, day +21 ± 7 (T3) and day +90 ± 20 (T4) after the second dose. Both groups received two doses of either BNT162b2 or ChAdOx1 nCov-19 (Oxford-AstraZeneca) vaccine 6-12 weeks apart (in accordance with UK government recommendations).Inclusion criteria were CML in chronic phase, current treatment with TKI and in at least complete cytogenetic remission. Exclusion from the study was determined by previous PCR-or serology-confirmed COVID-19 or by anti-SARS-CoV-2 immunisation with any of the available vaccines.Seroconversion for anti-RBD was confirmed using the Imperial double antigen-binding enzyme-linked immunosorbent assay (Imperial Hybrid DABA), which detects total anti-RBD with a specificity of 100% and a sensitivity of 98.9%. 10 All subjects gave their informed consent for participation in the study, which was approved by the Health Research Authority (IRAS ID: 289527) and by the Research Ethics
Accurate and sensitive detection of antibody to SARS-CoV-2 remains an essential component of the pandemic response. Measuring antibody that predicts neutralising activity and the vaccine response is an absolute requirement for laboratory-based confirmatory and reference activity.
The viral receptor binding domain (RBD) constitutes the prime target antigen for neutralising antibody. A double antigen binding assay (DABA), providing the most sensitive format has been exploited in a novel hybrid manner employing a solid-phase S1 preferentially presenting RBD, coupled with a labelled RBD conjugate, used in a two-step sequential assay for detection and measurement of antibody to RBD (anti-RBD).
This class and species neutral assay showed a specificity of 100% on 825 pre COVID-19 samples and a potential sensitivity of 99.6% on 276 recovery samples, predicting quantitatively the presence of neutralising antibody determined by pseudo-type neutralisation and by plaque reduction. Anti-RBD is also measurable in ferrets immunised with ChadOx1 nCoV-19 vaccine and in humans immunised with both AstraZeneca and Pfizer vaccines. This assay detects anti-RBD at presentation with illness, demonstrates its elevation with disease severity, its sequel to asymptomatic infection and its persistence after the loss of antibody to the nucleoprotein (anti-NP). It also provides serological confirmation of prior infection and offers a secure measure for seroprevalence and studies of vaccine immunisation in human and animal populations.
The hybrid DABA also displays the attributes necessary for the detection and quantification of anti-RBD to be used in clinical practice. An absence of detectable anti-RBD by this assay predicates the need for passive immune prophylaxis in at-risk patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.