• Users Online: 793
  • Print this page
  • Email this page


 
 
Table of Contents
ORIGINAL ARTICLE
Year : 2022  |  Volume : 13  |  Issue : 4  |  Page : 216-220

Effect of SARS-CoV-2 vaccination on severity and outcome of COVID-19 among health-care workers of a tertiary care hospital in India


1 Department of Microbiology, VMMC and Safdarjung Hospital, New Delhi, India
2 Department of Pulmonary and Critical Care Medicine, VMMC and Safdarjung Hospital, New Delhi, India
3 Department of Community Medicine, VMMC and Safdarjung Hospital, New Delhi, India

Date of Submission11-May-2022
Date of Decision26-Jun-2022
Date of Acceptance26-Jun-2022
Date of Web Publication18-Oct-2022

Correspondence Address:
Dr. Pranav Ish
Room Number 638, Superspeciality Block, VMMC and Safdarjung Hospital, New Delhi - 110 029
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/injms.injms_56_22

Rights and Permissions
  Abstract 


Introduction: SARS-CoV-2 vaccines decrease the risk of infection. However, data on the utility of vaccines in decreasing the severity of COVID-19 need to be evaluated. This study was carried out with the primary objective to assess the severity and clinical outcome of COVID-19 infections among unvaccinated and vaccinated health-care workers (HCWs). Methods: This was a hospital-based retrospective cohort study including all HCWs who developed microbiologically confirmed COVID-19 over 6 months from January 31, 2021, to July 31, 2021 (during the second wave of COVID-19 in India). Data were recorded through a questionnaire which included demographic details, primary location of work, history of vaccination with dates, comorbidities, severity of COVID-19, and outcome. HCWs who tested positive for SARS-CoV-2 before any dose of the COVID-19 vaccine were included in the “unvaccinated” group. Whereas HCWs who developed SARS-CoV-2 after a single or both doses of vaccine were included in the vaccinated group. The outcome and mortality among the vaccinated and unvaccinated groups were evaluated and compared. Results: The study included 500 HCWs who developed a microbiologically confirmed CVOID-19 infection. It was a predominantly middle-aged population with 247 unvaccinated and 253 vaccinated at the time of developing COVID-19. Only one-fourth of the population (26%) was working in the COVID-19 area and the source of COVID-19 to most was either a COVID-19 patient (39%) or a colleague (38%). Around 13% of the population had comorbidities with cardiovascular disease and diabetes being the most common. The majority of the patients were mild (71%) and most were treated at home in isolation (91%). Only 4% of the study population required intensive care. Among the vaccinated group, COVID-19 infection was predominantly mild and this difference was statistically significant as compared to the nonvaccinated. No difference was found in mortality among the two groups; however, the overall mortality was only 1%. Conclusions: SARS-CoV-2 vaccines reduce the severity of COVID-19 besides preventing infections and its spread. This can help in effective care of COVID-19 in home isolation without overburdening the health-care services. More studies including clinical parameters and microbiological components are required to understand the true extent of this protection of vaccines from severe forms of COVID-19.

Keywords: COVID-19, efficacy, health-care workers, severity, vaccine


How to cite this article:
Gaind R, Gupta NK, Nath R, Srivastava N, Gahlot T, Ish P, Gupta N. Effect of SARS-CoV-2 vaccination on severity and outcome of COVID-19 among health-care workers of a tertiary care hospital in India. Indian J Med Spec 2022;13:216-20

How to cite this URL:
Gaind R, Gupta NK, Nath R, Srivastava N, Gahlot T, Ish P, Gupta N. Effect of SARS-CoV-2 vaccination on severity and outcome of COVID-19 among health-care workers of a tertiary care hospital in India. Indian J Med Spec [serial online] 2022 [cited 2023 Jun 4];13:216-20. Available from: http://www.ijms.in/text.asp?2022/13/4/216/358777




  Introduction Top


COVID-19 vaccination was initially started in India on January 16, 2021, for health-care workers (HCWs), followed by frontline workers and the elderly population (60 years plus). Later, vaccination expanded to the middle-aged population with comorbidities (45–60 years), followed by all middle-aged population, and eventually to young adults (18–45 years). The national protocol was followed which included two doses given 1 month apart. Two vaccines Covaxin (inactivated vaccine made indigenously by Bharat Biotech) and Covishield (carrier vaccine made by AstraZeneca) were approved and the world's largest vaccination drive was launched.[1] Our tertiary care center was designated as one of the sites for COVID-19 vaccination where Covaxin alone was administered.

Our hospital was also designated as a referral hospital for the management of COVID-19 patients on March 1, 2020, and was one of the largest COVID-19 care facilities in the capital city. For effective implementation of infection prevention and control practices for COVID-19, an isolated block inside the hospital premises was converted into a dedicated COVID-19 care facility. Therefore, a small group of hospital staff including medical, paramedical, and nonmedical staff were posted at this facility, whereas the rest of the hospital staff continued working in the non-COVID area to continue uninterrupted patient care. The HCWs posted in the COVID-19 facility were trained for appropriate use of personal protective equipment (PPE) and COVID-19 preventive measures. Eventually, this training was imparted to the entire health-care staff of the hospital. There were designated sites for entry into the COVID-19 area after donning the appropriate PPE. Any patient in the non-COVID area who developed COVID-19 infection was immediately shifted to the COVID-19 area with the appropriate PPE.

COVID-19 vaccination helps in decreasing chances of infection and decreased transmission.[2] Even though both the vaccines had proven efficacy in phase III trials, data from India postnationwide mass vaccination can only help understand the benefits of vaccination in a holistic perspective.[3] A recent study from the United States using an agent-based model of SARS-CoV-2 transmission has demonstrated reduced infection, severity, intensive care unit (ICU) admission, and deaths, especially among the elderly age groups postvaccination. Similarly, a Susceptible-Exposed-Infectious-Recovered model-based study has found reduced transmission and hospitalization including deaths and it was concluded that early vaccination with even a less effective vaccine is the key to reduced hospitalizations and deaths.[4] There are multiple studies on breakthrough COVID-19 infection postvaccination,[5] vaccines decrease the risk of infection. However, data on the utility of vaccines in decreasing the severity of COVID-19 are limited and need to be evaluated including in India.[6] This is particularly relevant as they are the backbone of the hospital which is probably the reason why vaccination was initially launched for HCWs. This study was carried out with the primary objective to assess the severity of COVID-19 infections among unvaccinated/vaccinated and partially vaccinated HCWs. The secondary objective was to assess the clinical outcome of COVID-19 infection among unvaccinated/vaccinated and partially vaccinated HCWs.


  Methods Top


This was a hospital-based retrospective cohort study carried out in our tertiary care hospital providing management to COVID-19 patients. All HCWs who developed COVID-19 confirmed by reverse transcription-polymerase chain reaction (RT-PCR)/nucleic acid amplification test (NAAT)/rapid antigen test (RAT) from January 31, 2021, to July 31, 2021, were included (during the second wave of COVID-19 in India). Confirmatory RT-PCR tests were performed and interpreted as per the ICMR guidelines. The status of vaccination for COVID-19 was recorded along with their demographic, clinical profile, and outcome. HCWs who tested positive for SARS-CoV-2 before any dose of the COVID-19 vaccine were included in the “unvaccinated” group. Whereas HCWs who developed SARS-CoV-2 after a single or both doses of vaccine were included in the vaccinated group. This was done because the vaccine we rolled out on January 16, 2021, as per national guidelines, the two doses of vaccination were given 28 days apart and the second wave of the COVID pandemic started upsurging as early as March 2021 by which time most of the HCWs have received only one dose. Microbiologically negative and clinically suspected COVID-19 patients were excluded from the cohort. The starting point of the study was a telephonic collection of data of HCWs who were microbiologically confirmed COVID-19. Those HCWs who denied consent or could not be contacted were excluded. Data were telephonically recorded from the kin of the patient in case of death due to COVID-19, or else it was obtained retrospectively from the patients. Records of the admitted patients were also reviewed wherever available.

Data were collected telephonically after the confirmation of identity by the validated government document submitted at the time of testing for SARS-CoV-2. The response was on a voluntary basis, and if the participant agreed, it was recorded through a questionnaire. Data included demographic details, primary location of work (COVID-19/non-COVID area), history of vaccination, comorbidities, management (home or hospital-ICU/isolation ward as per the ministry of health and family welfare (MOHFW) guidelines),[7] severity of disease (mild/moderate/severe) based on the minimum saturation of oxygen recorded, and the outcome was recorded. All patients selected according to the inclusion and exclusion criteria were evaluated for the severity of COVID-19 into mild/moderate/severe categories. HCWs who reported oxygen saturation above 93% O2 were classified as mild, those who reported 90%–93% O2 were classified as moderate, and those who reported <90% O2 were classified as severe. The O2 saturation was self-reported by the HCW during the interview.[7] The source of the data regarding vaccination is the Indian Council of Medical Research (ICMR)/specimen referral form (SRF) form for COVID-19 testing, which mandates the recording of vaccination status as one of the components. Data on clinical profile and outcome were telephonically recorded from the kin of the patient in case of death due to COVID-19, or else it was obtained retrospectively from the patients. For admitted patients, the medical records were also reviewed for clinical profile and outcome along with telephonic confirmation. The outcome and mortality among the vaccinated and unvaccinated groups were evaluated and compared.

The principles outlined in the Declaration of Helsinki were followed in the study. Data acquired in this retrospective study were kept anonymous. Patients' details were only available to investigators. All data were collected in a predesigned proforma and analyzed. Parametric data were represented as mean and standard deviations. The Chi-square test was used to compare categorical variables. A two-tailed “P value” of less than 0.05 was considered significant.


  Results Top


The demographic profile, disease severity, and outcome of HCW with COVID-19 are presented in [Table 1]. The age of the majority (83%, n = 419) of the HCW ranged 18–45 years and with nearly equal gender distribution as shown in [Table 1]. Nearly half of this study group were unvaccinated (49.4%, 247/500) and 50.6% (n = 253) were vaccinated at the time of developing COVID-19. Approximately one-fourth of the enrolled HCW (26%) were working in the COVID-19 area. The likely source of COVID-19 infection among the HCWs was either exposure to a COVID-19-positive patient (39%) or a colleague (38%). The majority of the HCW presented with mild (71%) disease and most were successfully managed with home isolation (91%). Only 4% of the HCWs with COVID-19 infection required intensive care and mortality overall was only 1% and only 2.6% required oxygen support at discharge. Around 13% of the population had comorbidities with cardiovascular disease and diabetes being the most common. Among the vaccinated group, COVID-19 infection was predominantly mild and this difference was statistically significant as compared to the nonvaccinated group as shown in [Table 2]. No difference was found in mortality among the two groups.
Table 1: Demographic profile, clinical severity, and outcome of health-care workers with laboratory-confirmed COVID-19 infection

Click here to view
Table 2: Profile, clinical severity, and outcome of health-care workers who developed COVID-19 in relation to vaccination status

Click here to view



  Discussion Top


This was a study done on HCWs of a tertiary care hospital involved in the management of COVID-19 in India. As it is evident, the majority of HCWs presented with mild disease. It has been well documented that most of the COVID-19 infections are mild and patients recover with conservative therapy. However, these patients require isolation and hence even a mild infection in HCW can decrease the workforce and affect patient care. The source of infection was a patient or a colleague and uncommonly family members as most of these HCWs were staying in dedicated hostels for health-care staff and avoiding contact with family members for fear of the risk of spread of infection. However, the predominance of COVID-19 in health-care workers posted in non-COVID areas is a matter of concern. It is possible that COVID-19 appropriate behaviors were not followed in strict compliance in non-COVID areas due to a lack of training or compliance. Besides, asymptomatic infections in non-COVID areas could have led to increased spread of COVID-19. However, being a tertiary care hospital where COVID-19 was seen mostly by pulmonologists, medicine specialists, and intensivists, the other non-COVID departments' staff was definitely greater in proportion to the COVID-19 staff. Interaction between these two groups without appropriate PPE and precautions could have led to the transmission of disease to non-COVID staff.

This study is a real-time experience of the benefits of COVID-19 vaccination among HCWs in the second wave of COVID-19 in India. While undoubtedly, the second wave in 2021 had a greater spread, and COVID-19 positive cases,[8] vaccination before the second wave may have blunted the severity. Internationally multiple vaccines were approved and used after proving efficacy and safety in phase III trials. The presence of COVID-19 infection after vaccination is not uncommon.[9] However, the efficacy in preventing the infection is complemented by preventing a severe COVID-19 disease as evident in our study. COVID-19 vaccination has been proven to reduce both actual numbers of cases as well as the COVID-19-related complications along with hospitalizations in HCW[10] which is in line with our findings, in terms of the severity of disease.

There was no statistical difference among the vaccinated and unvaccinated in terms of mortality. However, this was probably due to the fact that the mortality was only seen in 6 (1.2%) patients overall. In the current study, most of the (84%) HCWs were under 45 years with only 13% of the study population with underlying comorbidities, which may suggest a better outcome in the majority of the patients, similar to the findings of Sabetian et al.[11] from Iran, which had a mean age of 35 years and 80% of HCWs without any comorbidity, leading to a less severe form of disease in the study population. Mutations are expected to occur during viral proliferation in SARS-CoV-2 as witnessed worldwide but the benefits of the vaccination program will probably continue,[12] as evident from the current study too.

The authors would like to point out few limitations of this study. Although a separate COVID-19 area was created within the hospital, the presence of COVID patients (suspects) in the non-COVID area cannot be ruled out. Moreover, since HCWs were exposed to such suspects/patients, it might have happened that HCWs had an episode of asymptomatic infection. A prior asymptomatic infection can offer some protection against COVID-19 even in the absence of vaccination. Second, the existing literature suggests that vaccine hesitancy was also present among HCWs, leading to the delay in vaccination or not getting vaccination at all.[13] Furthermore, those HCWs who took the first dose of vaccine, and were infected with COVID-19 before the second dose, had to defer the vaccination by 3 months. This data was collected from the time period when India was going through the second wave of the pandemic, the above factors might have played a role in vaccination drive and hence, the spread of COVID-19. Third, we did not take a history of following COVID-19 appropriate behavior during HCWs stay in the hospital/home.


  Conclusions Top


HCWs are the backbone of our fight against the COVID-19 pandemic. Our data suggesting less severe disease among vaccinated HCWs as compared to unvaccinated HCWs is certainly encouraging. Vaccines continue to provide protective effects against COVID-19 infection including the newer variants of concern. More studies including clinical parameters, microbiological components, and prospective in nature are required to understand the true extent of protection provided with vaccination against COVID-19.

Financial support and sponsorship

None.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Srivastava RK, Ish P; COVID-Vaccination Group S. The initial experience of COVID-19 vaccination from a tertiary care centre of India. Monaldi Arch Chest Dis 2021;91. [doi: 10.4081/monaldi. 2021.1816].  Back to cited text no. 1
    
2.
Kunal S, Aditi, Gupta K, Ish P. COVID-19 variants in India: Potential role in second wave and impact on vaccination. Heart Lung 2021;50:784-7.  Back to cited text no. 2
    
3.
Moghadas SM, Vilches TN, Zhang K, Wells CR, Shoukat A, Singer BH, et al. The impact of vaccination on COVID-19 outbreaks in the United States. medRxiv 2020. [doi: 10.1101/2020.11.27.20240051].  Back to cited text no. 3
    
4.
Haghpanah F, Lin G, Levin SA, Klein E. Analysis of the potential impact of durability, timing, and transmission blocking of COVID-19 vaccine on morbidity and mortality. EClinicalMedicine 2021;35:100863.  Back to cited text no. 4
    
5.
Teran RA, Walblay KA, Shane EL, Xydis S, Gretsch S, Gagner A, et al. Post vaccination SARS-CoV-2 infections among skilled nursing facility residents and staff members – Chicago, Illinois, December 2020-March 2021. MMWR Morb Mortal Wkly Rep 2021;70:632-8.  Back to cited text no. 5
    
6.
Tyagi K, Ghosh A, Nair D, Dutta K, Singh Bhandari P, Ahmed Ansari I, et al. Breakthrough COVID19 infections after vaccinations in healthcare and other workers in a chronic care medical facility in New Delhi, India. Diabetes Metab Syndr 2021;15:1007-8.  Back to cited text no. 6
    
7.
8.
Nath R, Gupta NK, Jaswal A, Gupta S, Kaur N, Kohli S, et al. Mortality among adult hospitalized patients during the first wave and second wave of COVID-19 pandemic at a tertiary care center in India. Monaldi Arch Chest Dis 2021;92. [doi: 10.4081/monaldi.2021.2034].  Back to cited text no. 8
    
9.
Keehner J, Horton LE, Pfeffer MA, Longhurst CA, Schooley RT, Currier JS, et al. SARS-CoV-2 infection after vaccination in health care workers in California. N Engl J Med 2021;384:1774-5.  Back to cited text no. 9
    
10.
Shah AS, Gribben C, Bishop J, Hanlon P, Caldwell D, Wood R, et al. Effect of vaccination on transmission of SARS-CoV-2. N Engl J Med 2021;385:1718-20.  Back to cited text no. 10
    
11.
Sabetian G, Moghadami M, Hashemizadeh Fard Haghighi L, Shahriarirad R, Fallahi MJ, Asmarian N, et al. COVID-19 infection among healthcare workers: a cross-sectional study in southwest Iran. Virol J 2021;18:58.  Back to cited text no. 11
    
12.
Sapkal GN, Yadav PD, Ella R, Deshpande GR, Sahay RR, Gupta N, et al. Inactivated COVID-19 vaccine BBV152/COVAXIN effectively neutralizes recently emerged B.1.1.7 variant of SARS-CoV-2. J Travel Med 2021;28:taab051.  Back to cited text no. 12
    
13.
Kishore J, Venkatesh U, Ghai G, Heena, Kumar P. Perception and attitude towards COVID-19 vaccination: A preliminary online survey from India. J Family Med Prim Care 2021;10:3116-21.  Back to cited text no. 13
  [Full text]  



 
 
    Tables

  [Table 1], [Table 2]



 

Top
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
Abstract
Introduction
Methods
Results
Discussion
Conclusions
References
Article Tables

 Article Access Statistics
    Viewed1564    
    Printed64    
    Emailed0    
    PDF Downloaded111    
    Comments [Add]    

Recommend this journal