Effect of COVID-19 Pandemic on Routine Immunization at a Tertiary Care Centre

Introduction

The novel corona virus disease (COVID-19 pandemic) caused by severe acute respiratory syndrome Corona virus 2 (SARS-CoV-2) drew worldwide attention as a public health emergency of international concern and negatively impacted every aspect of life.¹ Vital intervention strategies including partial or complete lockdown, curfews, travel bans etc. were implemented to curb community transmission due to which primary healthcare services including immunization got disrupted, putting women and children at an increased risk for acquiring vaccine preventable diseases (VPD) such as measles, mumps, rotaviral disease and typhoid.² Lack of public transport, fear of acquiring COVID-19 infection on visiting hospitals, lack of supply of vaccines were some of the factors that contributed to the delayed or missed immunizations.²

According to the World Health Organization (WHO), VPD could be a threat to about 80 million children worldwide because of the disruption of healthcare services due to the COVID-19 pandemic.¹ The incidence of VPDs in India is also expected to rise in the near future as a collateral damage of the pandemic.³ Disruption of vaccination must be avoided to prevent VPD outbreaks. The need of the hour is to bridge the existing vaccination gaps and prevent the risk of VPD epidemics. High quality supplementary immunization activities should be conducted and routine immunization activities strengthened to enable the same.

To date, there are few reports regarding the impact of COVID-19 pandemic on childhood immunization, especially in the Indian setting. With this study, we aimed to find the occurrence and frequency of delayed childhood vaccinations during the COVID-19 pandemic at our hospital. The findings of the study can help identify the obstacles to vaccinations in public health emergencies and may prompt the implementation of appropriate strategies and logistics to prevent disruption of immunization services in the future.

COVID-19 pandemic has affected all spheres of life including immunizations. Understanding the magnitude and planning catch-up immunization may be needed for prevention of surge in vaccine preventable diseases in the future.

Materials and Methods

It was a descriptive record-based study from the immunization out-patient clinic at Father Muller Medical College Hospital, Mangalore. It is a tertiary care center located in the Dakshina Kannada district of Karnataka which was a high transmission zone for SARS-CoV-2 infections. All the children aged 0-15 years who attended the immunization clinic from March 2019 to August 2021 were included in the study after obtaining clearance from the Institutional Ethics Committee (Ref. No. FMIEC/CCM/860/2021). Purposive sampling was done. The duration of the study was divided into the following phases:

Pre COVID phase: March 2019 to February 2020

Lockdown phase 1: March 2020 to May 2020

Unlock phase 1: August 2020 to September 2020

Lockdown phase 2: May 2021 to June 2021

Unlock phase 2: July 2021 to August 2021

Data collection was done from immunization records of all children aged 0 days to 15 years who attended the immunization clinic in the time period mentioned. Vaccines taken as per the national immunization schedule along with optional vaccines taken were recorded. Data was analyzed and depicted in the form of time trends for each period of lockdown and unlock.

Results

Our study showed that there was a significant difference in the number of vaccines administered in the pre COVID and COVID phases. The number of vaccine doses administered significantly reduced during the pandemic as compared to the pre COVID phase as depicted in Table 1.

There was a sudden massive dip in the vaccination rates during lockdown I, which marginally picked up during the unlock phase and a second dip was again seen during lockdown II as seen in Figure 1. Maximum reduction was noted with optional vaccines.

However, unlock period also showed decreased number of vaccinations as compared to pre COVID phase.

Discussion

In our study, the overall decrease in the vaccination can be attributed to the strict lockdown policies imposed during the pandemic. Lack of public transport, fear of contracting COVID, unavailability of vaccination appointments due to the lockdown could be the possible reasons. As the hospital happened to be in the containment zone, there was a decrease in the overall number of deliveries as well, which could account for the decrease in the number of birth dose vaccines administered.

According to the UNICEF, 23 million children missed out on basic vaccines through routine immunizations in 2020. About 17 million of these children did not receive a single vaccine during the year, widening the already immense inequities in vaccine access. Most affected were the WHO South-East Asian and Eastern Mediterranean regions.^4-9 India is at the top of the list of countries with maximum reduction in vaccination rates.^4,7,8

After the lockdown was lifted, people may not have been aware that the immunization services have resumed. This could account for the low rates of vaccinations even in the unlock phase.

This indicates that routine vaccination suffered overall, over the course of pandemic period. This could probably be explained by the parents’ fear of their children contracting COVID during the hospital visits as COVID cases still remained rampant even in the unlock phase.

However, during the second lockdown, almost a year later, the immunization services were made available with safety precautions in place.

Because of this decreasing trend in vaccinations and failure to administer catch up vaccinations in many children, there is possibility of a health crisis in the near future. There could be a slow rise in the numbers of vaccine preventable diseases as a collateral damage of the lockdown circumstances surrounding the Coronavirus spread. In recent times, we have been seeing a possible resurgence of measles in the form of epidemics in different parts of the country.

In a retrospective analytical study conducted by Patel P et al.³ in Ahmedabad, Gujarat, where they compared the immunization statistics from the lockdown period in April and May to the same period in the pre Covid phase, it was found that there was an overall decrease in the vaccination coverage during the whole lockdown period compared to the previous year except for birth vaccinations. The maximum reduction was seen with MR vaccine and DPT booster followed by pentavalent vaccines.³

In a retrospective analytical study conducted at a tertiary care center in Uttar Pradesh, Agrawal et al. found that the total number of vaccine beneficiaries decreased significantly post lockdown. There was a significant reduction in the unlock period when compared to pre COVID phase as well. Percentage reduction was maximum in booster doses while birth dose group was least affected. No significant catch up in vaccine beneficiaries was noted in the unlock period.⁴

In the United States, data was collected from 1000 pediatricians and it showed 50% reduction in measles and rubella vaccination, 42% reduction in diphtheria and whooping cough vaccination during the initial two weeks of lockdown.³

Harris et al. in their cross-sectional study on the impact of COVID-19 on routine immunization in South-East Asia and Western Pacific noted that 95% countries reported vaccination disruptions. Infancy and school entry age vaccinations were most impacted.⁸

Limitations

1. This was a retrospective record-based study and only data pertaining to number and type of vaccines taken during the study period were collected.
2. Age and gender-wise subgroup analysis was not done.
3. COVID vaccination status of our study participants was not available as it began in a phased manner only in the year 2022 for children in India, which was beyond our study period.

Conclusion

The most cited reasons for disrupted vaccinations across the globe were fear of infection, movement or travel restrictions and limited accessibility to healthcare. In order to prevent the dreaded outbreak of vaccine preventable diseases preventive measures have to be put in place and aggressive approach in catch up vaccinations is necessary. Additional vaccination campaigns may need to be conducted. Helping health workers and community leaders communicate actively with caregivers to explain importance of vaccinations, rectifying gaps in immunization coverage, including identifying communities and people who have been missed during the pandemic are some of the strategies that can be implemented.

Funding sources / grants

None

Conflict of Interest

None

Acknowledgement

We would like to thank the nurses and data entry operators from the immunization clinic of our hospital.