Analysing Global COVID-19 Vaccination Trends

📌 Project Summary

Vaccinations have been the cornerstone of global efforts to curb the COVID-19 pandemic. In this project, I analysed worldwide COVID-19 vaccination data using SQL to uncover trends, identify global disparities, and highlight progress over time. The analysis involved designing a relational data model, writing complex SQL queries, and presenting insights visually through Excel dashboards.

🗂 Dataset Details

I used the Our World in Data COVID-19 Vaccination Dataset, which compiles regularly updated global vaccination statistics. The dataset includes:

• Total vaccinations administered
• Number of people vaccinated (1st and 2nd doses)
• Daily vaccination rates
• Population-adjusted vaccination coverage As of April 7, 2021, data spans 169 countries, aiding policymakers, researchers, and public health stakeholders in tracking progress and identifying gaps.

⚙️ Data Processing & ER Diagram

To make the dataset analysis-ready:

• I structured it into relational tables (e.g., Countries, VaccinationStats, PopulationData).
• Developed an Entity-Relationship (ER) diagram to capture links between countries, doses, and dates.

Entity-Relationship Diagram

• Cleaned and standardised date formats and missing values for consistency.

🧠 SQL Queries & Insights

Using advanced SQL queries, I extracted key insights:

• Running Total of the Number of People Who Have Taken the Vaccine For Each Observation Day

A running total tracks the cumulative number of people vaccinated each day, providing a clear view of overall progress and helping identify trends in the vaccine rollout over time.

SQL Query

Results

• Cumulative Numbers of COVID-19 Doses Administered by Each Country:

Cumulative numbers of COVID-19 doses administered by each country help measure the scale and pace of each nation’s vaccination campaign, enabling comparisons across countries and informing global health strategies.

SQL Query

Results

India leads in the total number of COVID-19 vaccine doses administered, followed by the United States and Brazil. This high volume is largely influenced by population size, but it also reflects the scale and intensity of each country’s vaccination drive. These figures highlight the logistical efforts and public health prioritisation in densely populated nations.

• Speed of Vaccination Administration by Country

The speed of vaccination administration by country helps assess how quickly nations are protecting their populations, identify leaders and laggards in rollout efficiency, and guide resource allocation and policy decisions during a health crisis.

SQL Query

Result

The image shows a table displaying the monthly COVID-19 vaccine doses administered in four countries from January 2022 to June 2022. The countries included are:

• Australia
• United States
• England
• New Zealand

Key Observations:

• England consistently administered the highest number of doses each month, followed by the United States.
• Australia and New Zealand had significantly lower vaccination counts compared to England and the U.S., likely due to smaller populations.
• There are fluctuations in the monthly figures for all countries, indicating changing vaccination rates over time.

The table helps track vaccination trends and volumes across countries on a month-by-month basis, which is useful for comparing the pace and scale of each country’s vaccination efforts.

💡 Key Learnings

• Learned to handle real-world, imperfect public datasets using SQL.
• Strengthened query design by applying aggregation, subqueries, joins, and window functions.
• Gained deeper insight into global public health efforts and data-driven decision-making.
• Reinforced the importance of effective data visualisation for storytelling.

🔗 Project Links

• 💻 GitHub Repository: Contains SQL scripts, ER diagram, and dataset files.

https://github.com/Samay9812/Coivd-19-vaccination