ABSTRACT
Introduction: In view of the present Coronavirus Disease 2019 (COVID-19) pandemic it is of utmost importance to look out for the 'trojan horse' that is the asymptomatic population who are potential for spreading the disease. Healthcare Workers (HCWs) are the most vulnerable group. The possibility of having the infection does not always correlate well with the symptoms. It urges the need for development of certain special plans beyond continuous surveillance and symptom monitoring. Aim: To explore asymptomatic COVID-19 infection among HCWs as a potential source of transmission. Materials and Methods: This hospital-based cross-sectional study was conducted at Medical College and Hospital, Kolkata, West Bengal, India, from June 2020 to September 2020. The data were collected from 714 HCWs over a period of three months of study period, with the help of a standard questionnaire and blood sample was analysed by serological assessment of Immunoglobulin G (IgG) for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by EUROIMMUN Kit, Enzyme-Linked Immunosorbent Assay (ELISA). Epi info software 7, available from the World Health Organization (WHO) site was used to manage and analyse the data. Results: The mean age was 35.30 +/- 11.79 years. Out of 714 people, 54.8% (391/714) were male and 45.2% (323/714) were female. In this survey, 9.16% of HCWs in COVID-19 designated duties were IgG positive;whereas 21.89% of HCWs designated in other parts of area were detected to be IgG positive. Seroprevalence was least amongst nursing staffs with 5.41% (8/148);among doctor's it was 9.62% (41/426). Most interestingly among ward boys and cleaners this prevalence was found to be 29.90% (29/97) being the highest. Overall seroprevalence for IgG against SARS-CoV-2 was found to be 12.75% (91/714). Conclusion: This serosurvey at this tertiary COVID-19 care facility is a unique venture to look for the possible sources of super-spread. The high rate of sero-positivity among ward boys and cleaners might be due to their lack of knowledge and training regarding steps to prevent a droplet borne pandemic. This study also points out that if adequate precautions are taken, infectivity is not to an alarming extent, even in a full-fledged COVID-19 care hospital.
ABSTRACT
At a regional and local level, the COVID-19 pandemic has not spread out uniformly and some German municipalities have been particularly affected. The seroepidemiological data from these areas helps estimate the proportion of the population that has been infected with SARS-CoV-2 (seroprevalence), as well as the number of undetected infections and asymptomatic cases. In four municipalities which were especially affected, 2,000 participants will be tested for an active SARS-CoV-2 infection (oropharyngeal swab) or a past infection (blood specimen IgG antibody test). Participants will also be asked to fill out a short written questionnaire at study centres and complete a follow-up questionnaire either online or by telephone, including information on issues such as possible exposure, susceptability, symptoms and medical history. The CORONA-MONITORING lokal study will allow to determine the proportion of the population with SARS-CoV-2 antibodies in four particularly affected locations. This study will increase the accuracy of estimates regarding the scope of the epidemic, help determine risk and protective factors for an infection and therefore also identify especially exposed groups and, as such, it will be crucial towards planning of prevention measures.