ABSTRACT
BACKGROUND Most individuals with Covid-19 infection develop antibodies specific to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the dynamics of these antibodies is variable and not well-studied. We aimed to determine the titres of naturally acquired antibodies over a 12-week follow-up. METHODS We recruited healthcare workers who had tested positive on a specific quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for SARS-CoV-2, and then tested for the presence of immunoglobulin G (IgG) antibody against the same virus at baseline and again at 6 and 12 weeks. The antibody titre was determined by a semi-quantitative assay based on signal/cut-off ratio. Healthcare workers with antibody positivity were divided into those with high titre (ratio ?12) and low titre (<12). Their demographic details and risk factors were surveyed through a Google form and analysed in relation to the antibody titres at three time-points. RESULTS Of the 286 healthcare workers, 10.48% had high antibody titres. Healthcare workers who had tested positive by qRT-PCR and those who had received the Bacille Calmette–Guérin (BCG) vaccination or other immune-boosters had a higher frequency of high antibody titres. While there was a significant decline in antibody titres at 6 and 12 weeks, 87.46% of individuals positive for IgG antibody persisted to have the antibody even at 12 weeks. CONCLUSION Healthcare workers who tested positive for SARS-CoV-2 on qRT-PCR had a high positivity for the specific antibody, which continued to express in them even at 12 weeks. Further follow-up is likely to enhance our understanding of antibody kinetics following SARS-CoV-2 infection.
ABSTRACT
Abstract: In this study we evaluated the analgesic and anti- inflammatory activities of the methanol extract of stem bark of Diospyros cordifolia (MEDC) Roxb. The analgesic effects of the stem bark of the plant was assessed in mice using the tail-flick method while carrageenan, histamine and dextran induced paw oedema was used to study the antiinflammatory effects in rats. The MEDC exhibited significant (p<0.01) analgesic effects comparable to the reference drug diclofenac sodium. MEDC also was evaluated for its anti-inflammatory potential against carrageenan, histamine and dextran induced rat paw edema. The methanol extract (25 and 50 mg / kg body weight) exhibited significant (p<0.01) activity against all phlogistic agents used in a dose dependent manner. All these effects were compared with reference drug phenylbutazone (100 mg/kg body weight)