Health Care Settings Can Benefit From Serosurveys to Design Infection Control Practices

Study results show immunoglobulin G antibodies were detected in 13 of 382 individuals in the first phase and 71 of 168 in the second, with age and vaccination status contributing factors.

Serosurveys in health care settings can help identify infectious disease transmission patterns and redesign infection control practices, according to the results of a study published in Cureus.

According to investigators, 382 and 168 health care workers took part in 2 phases of a cross-sectional study. The study was conducted at Pondicherry Institute of Medical Sciences, a tertiary care center, and was used to detect immunoglobulin G (IgG) antibodies to SARS-CoV-2.

Individuals in the study were excluded if they had active symptoms of COVID-19.

In both phases, seropositivity was calculated, where possible associations were determined using regression analysis.

IgG antibodies were detected in 13 of 382 individuals in the first phase and 71 of 168 in the second.

Investigators determined that the individual’s age and receiving 1 dose of the vaccine were factors associated with the antibodies. However, comorbidities, exposure to COVID-19 cases, job type, and sex were not associated with antibodies.

In the first phase, approximately 47.1% of participants were doctors, 29.8% were ancillary staff, 18.1% were nurses, and 5% were laboratory personnel. The mean age was 33.4 years, with 34% were male and 64.9% working in areas that put them in direct contact with patients.

Additionally, 23.8% had contact with patient specimens with high risks, such as aerosols or sputum, and all but 2 individuals had contact with individuals with suspected COVID-19 within the prior 3 months.

Of those individuals, 71.7% were not using personal protective equipment (PPE) at the time of contact with these individuals.

Approximately 43.5% of health care workers had contact with a confirmed case of COVID-19 in the prior 3 months, either in the community or hospital setting, and of these individuals, 62.7% were using PPE at the time of contact.

The most common comorbidities in this group were diabetes and hypertension, though chronic kidney and lung disease were also present.

In the second phase, samples were taken after a 4-month gap, and investigators noted that several of the individuals from the first phase had been infected by COVID-19.

Of the 168 health care workers, 71 had IgG antibodies to SARS-CoV-2, where 56 were doctors, 7 were nurses, 6 were ancillary staff members, and 2 were laboratory personnel.

Approximately 72.6% were unvaccinated, while the rest had received at least 1 dose of a COVID-19 vaccination.

Additionally, approximately 57.1% worked in areas with direct contact with patients, and 32.7% worked with patient specimens.

Approximately 42.5% had a history of contact with individuals with suspected COVID-19, and 39.3% were in contact with confirmed cases of COVID-19 in the prior 3 months.

Older age and receiving 1 or both doses of the vaccine were factors associated with the presence of antibodies in this study.

Investigators noted that the reporting of COVID-19 cases was low at the time of the first phase of the study, which could explain the low rate of antibodies present.

The seroprevalence increased by 42.3% between both phases, they said.

The study’s limitations included the timing of the second phase, with vaccination rollout just beginning, which may have contributed to the seropositivity during this time, investigators said.

Reference

Basheer A, Kanungo R, Ratnam VJ, Kandasamy R. Immunoglobulin G antibodies to SARS-CoV-2 among health care workers at a tertiary care center in South India. Cureus. 2022;e22520. doi:10.7759/cureus.22520