Evaluation of IgG Antibody Response to Severe Acute Respiratory Syndrome Coronavirus-2 in Healthcare Workers in a Tertiary Care Centre, Chennai, India

Introduction: Globally, the Coronavirus Disease-2019 (COVID19) pandemic poses a high risk for Healthcare Workers (HCWs) who are among the population that is most vulnerable of being infected with Severe Acute Respiratory SyndromeCoronavirus-2 (SARS-CoV-2). With a prevailing pandemic such as COVID-19, it becomes important to understand the presence and persistence of antibodies in the serum of HCW, testing positive for COVID-19 on Reverse transcriptase Polymerase Chain Reaction (RT-PCR). An understanding of the prevalence of IgG antibodies against COVID-19 and the duration for which they are present in the serum will help in predicting the immune response of individuals against the disease. Aim: To study the prevalence of COVID-19 IgG antibodies in laboratory confirmed COVID-19 RT-PCR positive symptomatic, asymptomatic and RT-PCR negative subjects. Materials and Methods: The present longitudinal study was conducted from April 2020 to December 2020 with a sample size of 90 participants based on a pilot study. Blood sample was collected and serum was separated. Enzyme Linked Immunosorbent Assay (ELISA) was done to detect the presence of COVID-19 IgG antibody in serum. Chi-square test and Pearson correlation were used to find out the statistical significance of COVID-19 IgG antibodies in COVID-19 positive and negative HCWs and the relationship between Cycle threshold values (Ct) and antibody levels, respectively. Results: Fever with sore throat was the most common (33%) symptom. Chi-square test done to compare IgG among RT-PCR positive and negative subjects showed p-value of <0.00001 which was significant. However, statistical significance was not found (p-value 0.9973) with respect to COVID-19 IgG antibodies in RT-PCR positive COVID-19 asymptomatic and symptomatic subjects. Mean antibody index in symptomatic and asymptomatic was 3.7743±1.9834 and 3.571±1.7961, respectively. Average number of days, the antibodies persisted was 25 days-266 days. Conclusion: The prevalence of COVID-19 antibodies among RT-PCR positive symptomatic, asymptomatic and RT-PCR negative subjects was 88%, 67% and 27%, respectively. The maximum number of days antibodies persisted was 266 days. Further studies will elucidate whether these antibodies prevent re-infection

Oral Candidiasis among Cancer Patients Attending a Tertiary Care Hospital in Chennai, South India: An Evaluation of Clinicomycological Association and Antifungal Susceptibility Pattern

Oropharyngeal candidiasis is one of the common manifestations seen in cancer patients on cytotoxic therapy and invasion into deeper tissues can occur if not treated promptly. Emergence of antifungal drug resistance is of serious concern owing to the associated morbidity and mortality. The present study aims at evaluation of clinicomycological association and antifungal drug susceptibility among the 180 recruited patients with cancer on chemotherapy and/or radiotherapy with signs or symptoms suggestive of oral candidiasis. Speciation and antifungal susceptibility was done by Microbroth dilution method for fluconazole, Itraconazole, and Amphotericin B as per standard microbiological techniques. Chi-square test was used for statistical analysis (p<0.05 was considered statistically significant). Candida albicans was the predominant species isolated (94) (58%) followed by Candida tropicalis (34) (20.9%). Fluconazole and Itraconazole showed an overall resistance rate of 14% and 14.8%, respectively. All the isolates were susceptible to Amphotericin B. There was a significant association between the presence of dry mouth and isolation of Candida (p<0.001). Such clinicomicrobiological associations can help in associating certain symptoms with the isolation of Candida. Species level identification with in vitro antifungal susceptibility pattern is essential to choose the appropriate drug and to predict the outcome of therapy