(Table2)

(Table2). throughout their course of contamination. The seropositivity among the subjects was 28.9% (n = 118) and was found significantly higher among lower-middle socioeconomic strata (p= 0.01). The antibody levels were significantly higher (p= 0.033) in individuals with a previous history of COVID-19 like symptoms as compared to the subjects, who Lincomycin hydrochloride (U-10149A) had no such history. Asymptomatic healthcare workers showed a significantly increased rate of SARS-COV-2 contamination (p= 0.004) and seropositivity (p= 0.005) as compared to the non-healthcare workers. Subjects, who were exposed to contamination at their place of work (nonhospital establishing) had the least RT-PCR positivity rate (p= 0.03). == Conclusions == A large proportion of SARS-COV-2 contamination remains completely asymptomatic. The rate of asymptomatic carriage and seropositivity is usually significantly higher in healthcare workers as compared to the general populace. The level of SARS-COV-2 antibodies is usually directly related to the appearance of symptoms. These observations may contribute to redefining COVID 19 screening, contamination control, and professional health practice strategies. Keywords:SARS-COV2, Real-time RT-PCR, Seropositivity, Asymptomatic, Contamination == 1. Introduction == Asymptomatic carriage of SARS-COV-2 is perhaps one of the major difficulties in the control of COVID 19 pandemic. SARS-COV-2 differs from previously known SARS-COV-1 and Middle East Respiratory Syndrome Coronavirus (MERS-COV) in terms of severity, the onset of symptoms, and transmissibility [1]. The role of asymptomatic infections was not comprehended previously and was acknowledged much later in the pandemic [2]. Asymptomatic individuals escape the quarantine CANPml or self-isolation mechanism and remain mobile to infect a large number of people silently for an extended period [1,3]. Alternatively, not all contacts lead to contamination, and the contamination rate may depend on several associated factors [3,4]. Sero-conversion is known to happen within 23 weeks of contamination and the presence of neutralizing antibodies is usually important for viral clearance and reduction in chances of re-infection [5]. The 3rd serosurvey conducted between December 17, 2020, and January 8, 2021, showed the spread of SARS-COV-2 to 21.5% population [6]. These figures were quite high as compared to laboratory-confirmed COVID-19 positive cases (20 million by the end of May 2021) and escaping the screening mechanism in absence of symptoms can be one of the many reasons for it. Asymptomatic viral carriage is also important to diagnose as even in absence of overt disease, there is a possibility of development of silent changes in the lungs of the infected individuals that might require medical attention or manifest sequelae in later stages [3]. Very limited information is usually available from India outlining the asymptomatic carriage of SARS-CoV-2 in high-risk contacts and the factors associated with Lincomycin hydrochloride (U-10149A) it. In a developing country like India, factors like population density, education, personal hygiene, living condition, accessibility to medical facilities and laboratory assessments, etc may vary from region to region. These factors may directly or indirectly alter the rate of asymptomatic carriage Lincomycin hydrochloride (U-10149A) and the spread of diseases like COVID-19. The present study was aimed to identify the prevalence of asymptomatic SARS-COV-2 contamination and to estimate the seropositivity rate amongst high-risk contacts including HCWs in the southern district of Delhi, India. == 2. Materials and methods == This prospective cross-sectional study was conducted at a tertiary care hospital located in the south district of Delhi. Ethical clearance was obtained from the Institutional Ethics Committee (IEC) of Hamdard Institute of Medical Sciences and Research, New Delhi (letter no: HIMSR/IEC/001/2020, date: 07.08.2020). Post preliminary screening of 6961 subjects, a total of 407 asymptomatic healthy subjects, who experienced high-risk exposure with any laboratory-confirmed COVID-19 case were enrolled after obtaining written consent between 15thSeptember 2020 and 15thFebruary 2021. Any person who lives in the same household with a laboratory-confirmed COVID19 case, anyone within 1 meter of the confirmed case without precautions, Touched or cleaned the linens, clothes, or dishes of the patient, experienced direct physical contact with a positive patient without PPE, traveled in close proximity with a positive case or touched body fluids of the case without appropriate PPE were considered as High-risk contacts as defined by Integrated Disease Surveillance Programme, National Centre for Disease Control [7]. Individuals with symptoms consistent with COVID-19 in the last 2 weeks preceding sample collection or experienced tested positive for SARS-COV-2 earlier, those vaccinated for SARS-COV-2, those below 18 years and above 65 years of age, or experienced any co-morbidities were excluded from the study. Demographic details and the history of contact of each subject were collected by personal and telephonic interviews. History of any illness consistent with COVID 19 in Lincomycin hydrochloride (U-10149A) the last 4 months was recorded. The socio-economic.