Pattern of vaccination delivery around COVID-19 lockdown in Nigeria

ABSTRACT

COVID-19 pandemic has affected the world, including developing countries in various aspects. This pandemic might have severe consequences in terms of population health, especially in places where the health system is already weak. Using the health facility-level data over time, we evaluated the impact of COVID-19 lockdown on the vaccination service delivery in Nigeria. The lockdown was announced on March 30, 2020 and was effective until May 4, 2020. Compared to the quantity of vaccinations administered in March 2020, the quantity was significantly reduced during April 2020. The quantity was further reduced during May 2020. However, from June onwards, the quantity of vaccination administered has recovered. We observed that, although the lockdown reduced the quantity of vaccination administered significantly, it quickly recovered soon after the lockdown was relaxed.

Keywords:

• COVID-19
• lockdown
• service delivery
• vaccine delivery
• Nigeria

Introduction

COVID-19 pandemic continued to impact health systems across the globe in 2020.¹ Specifically, pandemics may disrupt vaccine delivery.² The impact of such a shock can be severe where the baseline health system is weak, especially in developing countries.³ In these countries, Nigeria inclusive, the disruption of the service delivery may trigger outbreaks of vaccine-preventable diseases. It is, therefore, crucial to investigate the extent of disruption of health services delivery during COVID-19 pandemic

In Nigeria, the federal government imposed a national lockdown on March 30, 2020. However, this national lockdown was short-lived, only until May 4, 2020 (Ajide et al. 2020).⁴ In sub-Saharan Africa, where vaccination coverage is limited, it might be anticipated that there will be a drop in vaccine delivery due to the lockdown. This study examined the effect of lockdown due to COVID-19 pandemic on the immunization delivery in Nigeria.

Methods

We used the health facility-level data collected by the Health Management Information System through the District Health Information Software 2 (DHIS2), which is an open-source platform. The author obtained the access to data through Primary Healthcare Development Agency. The DHIS2 data record monthly information on the quantity of various health services provided by all the health facilities in Nigeria from January to September 2020.

Using DHIS2 data, we observe the monthly number of vaccinations delivered at each health facility in each state before, during, and after the national lockdown due COVID-19 pandemic, in all Nigerian states. Nigeria consists of 36 states and 1 federal capital territory. Each state is divided by local government areas, where primary health facilities are located. Vaccination is administered at each primary health facility.

The federal government of Nigeria announced a national lockdown on March 30, 2020. The lockdown was imposed immediately in three states: Lagos, Abuja, and Ogun. Other states followed shortly after these three states. This lockdown lasted only till May 4, 2020. In other words, Nigeria experienced the lockdown in the month of April for the full month (Ajide et al. 2020).^4,5

In our study, we present the number of vaccinations administered at each health facility for five types of vaccine/vaccination: BCG, Penta1, Penta3, Measles, and Full vaccination. Full vaccination counts the number of children who received all the required vaccinations (BCG, OPV, Penta, and Measles) for their age.

First, we show the national trend of vaccination delivery over time. Second, we conduct OLS regression analysis which evaluates the effect of the lockdown on the vaccination delivery at state level, in the following regression framework:

(1) $y_{\mathit{hit}}=\mathit{\alpha }+{\beta }_1{\sum }_{t=1,t\ne 3}^9(\mathit{month}=\mathit{t})+v_h+{\epsilon }_{\mathit{it}}$(1)

where y_it is the number of vaccinations administered in a health facility h at a state i in the month of t in 2020. We employ OLS regression for its simplicity for the interpretation. The main independent variable is the set of dummy variables, and month = 3 (March, 2020) is the comparison group, which is right before the lockdown is initiated. We used the Health Facility Fixed Effect, v, to control for health facility-specific characteristics. Since we controlled for any variations within the health facility through the fixed effect, we did not include other covariates, also partially due to the limited data availability.

Finally, we show the zonal trend of vaccination delivery over time. Nigeria has six zones: north central (NC), north east (NE), north west (NW), south east (SE), south south (SS), and south west (SW).

Results

Figure 1 presents the monthly trend of the number of vaccinations administered at health facilities according to the type of vaccine at national level. We observed that the number of vaccinations administered was the lowest in May 2020 for any type of vaccines, but it recovered to the level prior to the lockdown in the following month – June 2020.

Figure 1. Number of vaccination administered by month, national average

Table 1 presents the regression result of the effect of lockdown on the number of vaccinations administered. Compared to the quantity of vaccinations administered in March 2020, the quantity was significantly reduced during April 2020. The quantity was further reduced during May 2020. However, from June onwards, the quantity of vaccinations administered has recovered.

Table 1. Effect of lockdown on the number of vaccinations administered

	BCG	Penta1	Penta3	Measles	Full vaccination
	(1)	(2)	(3)	(4)	(5)
Month = Jan	−0.132	2.103***	1.243***	1.930***	1.771***
	(0.845)	(0.127)	(0.143)	(0.196)	(0.154)
Month = Feb	−0.835	0.969***	0.861***	1.766***	1.488***
	(0.847)	(0.127)	(0.143)	(0.196)	(0.154)
Month = Apr	−1.127	−1.016***	−1.846***	−1.748***	−1.787***
	(0.851)	(0.128)	(0.144)	(0.197)	(0.154)
Month = May	−2.373***	−2.072***	−3.177***	−2.603***	−2.807***
	(0.854)	(0.129)	(0.145)	(0.198)	(0.155)
Month = Jun	−0.142	0.776***	−0.359**	−0.025	0.516***
	(0.847)	(0.128)	(0.144)	(0.196)	(0.154)
Month = Jul	−1.127	0.697***	0.282*	0.951***	0.798***
	(0.851)	(0.128)	(0.144)	(0.197)	(0.155)
Month = Aug	0.291	0.024	0.181	0.358*	0.204
	(0.849)	(0.128)	(0.144)	(0.196)	(0.154)
Month = Sept	0.562	1.158***	1.541***	1.277***	1.056***
	(0.866)	(0.130)	(0.147)	(0.200)	(0.158)
N	194237	203681	203241	198880	168690
r2	0.000	0.008	0.010	0.006	0.010

The regression controls for health facility fixed effect. The control group of the independent variables is Month = March, right before the lockdown (April 2020). N stands of the number of observation, r2 stands for the R-squared values. *significant at 10%; **significant at 5%; ***significant at 1%.

Figure 2 presents the monthly trend of the number of vaccinations administered at health facilities according to the type of vaccine, at zone level. Three northern zones (NC, NE, and NW) generally observed a decline in the quantity of vaccinations administered in May 2020, while southern states only observed a minor reduction in the month of April, or they did not observe a decline.

Figure 2. Number of vaccination administered, zonal average

Discussion

This paper reports on how vaccination service delivery was impacted due to the COVID-19 lockdown in Nigeria. The national lockdown in Nigeria is believed to have a large negative social and economic impact.⁶ The Nigerian health system was put to the challenge.⁷

We found that the national lockdown due to COVID-19 reduced the average number of vaccinations administered at national level, especially during the month of April and May, 2020, immediately after the national lockdown was announced at the end of March 2020. At national level, the reduction in the quantity of vaccinations administered was lower in April than in March, but it got further reduced in May.

However, soon after the lockdown was relaxed, the quantity of vaccination administered at national level recovered to the average level prior to the lockdown.

At zone level, we observed a reduction in the quantity of vaccinations administered in southern Nigeria by April 2020, while northern states observed such a reduction in May 2020. However, both southern and northern zones recovered 1 month after the reduction.

This gap in the effect of lockdown between southern and northern states might be due to the difference in the response of each state or of each zone to the national lockdown, difference in capacity, or other factors.

Overall, we observed that, although the lockdown reduced the quantity of vaccination administered significantly, they quickly recovered immediately after the lockdown was relaxed. However, we should be cautious in interpreting the result; this is because the lockdown was short-lived; thus, the data might not have captured the trend, and also because we only investigated the pattern of vaccine delivery using less than 1 year of monthly data, due to the limited data availability.

Conclusion

The reduction in the quantity of vaccinations administered due to the national lockdown due to COVID-19 was quickly offset soon after the lockdown was relaxed.

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.