Measles News Monitor
An automated monitor that pulls Google News feeds to surface the latest measles reporting and updates.
Epidemiologist • Public Health Communicator • Coder
Dr. Najera's Code Repository
Public health, data, teaching tools, and digital experiments.
This site brings together projects at the intersection of epidemiology, public health, GIS, communication, teaching, and coding. Some are practical tools. Some are educational experiments. Some are proof that epidemiologists also end up with too many browser tabs open.
About
Why this site exists
Hi, I'm Dr. Ren, an infectious disease and social epidemiologist with a background in public health, data, technology, and communication. This repository serves as a portfolio of coding-related work, with a focus on projects that help explain, analyze, teach, or explore public health questions.
I am especially interested in tools that make evidence easier to understand and easier to use. That includes data analysis, GIS, educational apps, simulations, and small web projects that turn abstract concepts into something people can actually see and interact with.
Projects
Selected work
Web tools and public health explainers
Vaccine News Monitor
A focused news tool for tracking vaccine-related coverage and developments as they happen.
Measles Learn
An interactive, evidence-based learning guide to the measles virus — modules, quizzes, and a timeline covering origins, virology, epidemiology, and vaccine history.
Vaccine Fact Generator
A quick way to surface concise, accurate vaccine facts in an accessible format.
Vaccine Map (US)
An 8-bit pixel-art interactive map of US state and territory school vaccine requirements and exemptions.
Herd Immunity Simulation
A mathematical simulation that shows how herd immunity works in practice as coverage changes.
Epidemiology Flash Cards
A study tool for introductory epidemiology learners who need core concepts to stick.
Biostat Compass
A stepwise statistical test selector for graduate public health students. Answer a short series of questions and it recommends the right test, explains the reasoning, and provides ready-to-adapt R and Python code.
Teaching tools and interactive games
Operation Salad Bar
The year is 1984, and a small Oregon town faces America's first deliberate biological attack. Players become disease investigators, reading the real story and answering epidemiology questions — bioterrorism, Salmonella, attack rates, epi curves — to earn XP and unlock each chapter.
Epi Detective
A retro 8-bit disease-investigation RPG where players solve outbreaks and rise from rookie to world-class disease detective, covering epi curves, odds ratios, and attack rates through progressively harder cases.
Kid Epi
A web application that teaches children the basics of epidemiology in a friendly, approachable way.
Vaccine Match Game
A simple matching game that teaches players about vaccines and the diseases they prevent.
Stop the Outbreak
An epidemiology quiz game where correct answers shrink a growing germ colony, turning core concepts into a timed outbreak-control challenge.
Screening Test Simulator
An interactive tool showing how prevalence, sensitivity, and specificity shape predictive values — and why the same result can mean very different things in different populations.
Random Candy Game
An interactive, playful way to introduce inferential statistics.
Roulette Simulator
A simple teaching tool for probability, randomness, and risk.
Genetic Shift and Drift
A quick simulation using examples from the literature to show how variation and change accumulate over time.
Nipah Outbreak Adventure
A choose-your-own-adventure where players try to stop an epidemic of Nipah virus disease. A work in progress.
History Bee Quiz
A fast-paced history quiz game with a leaderboard, built to review Frederick County, Maryland, and US history against a two-minute clock.
DOEPI: Outbreak Investigations
A revival of a 1997 CDC course on the principles of outbreak investigation, brought back to the modern web.
Geospatial analysis and GIS
Gun crimes near Baltimore schools
A spatial analysis of how many gun crimes occurred within 1,000 feet of Baltimore schools in 2018.
Philadelphia homicide hot spots
A GIS look at geographic clustering and patterning of homicides across Philadelphia.
GIS for Public Health
Teaching materials and examples for applying geographic information systems to public health questions.
Epi Applications of GIS (JHU)
Data and files for the Epidemiologic Applications of GIS course at Johns Hopkins, with companion R labs.
COVID-19 Vulnerability Mapping
Mapping population variables to identify which geographies were more vulnerable to COVID-19 infection.
Maryland Life Expectancy
Life expectancy in Maryland by census tract, drawn from the CDC USALEEP project.
Baltimore Homicide Inequity
An open-data project exploring the inequalities between poverty and homicide in Baltimore in 2016.
Baltimore Food Closures
Mapping food-establishment closures across Baltimore.
Data analysis and epidemiology
Excel to R
Exercises, datasets, and code for making the jump from Excel to R for epidemiologic analysis.
Fake Outbreak Investigation
A simulated outbreak investigation in R, built as a hands-on teaching dataset.
Measles Case-Control Study
A fictional case-control study of a measles outbreak, designed for classroom use.
Calendar Heat Map
An R project that renders a calendar heat map of homicides in Baltimore in 2016.
Screening Tests Dashboard
A Shiny dashboard showing how screening test performance is affected by disease prevalence.
Hardware and other experiments
Literary Clock (2026)
A literary clock for the Pimoroni Inky wHAT e-ink display: book quotes tell the time, with the time phrase bolded and a live analog clock.
Inky wHAT Weather Station
A cheap, hourly-updating weather station for the Pimoroni Inky wHAT e-ink display and Raspberry Pi Zero 2 W.
Inky PHAT Breaking News
Displays breaking news headlines every few minutes on a Pimoroni Inky PHAT e-ink screen.
Raspberry Pi Shutdown Button
A small hardware project adding a safe physical shutdown button to a Raspberry Pi.
Approach
Why coding matters in public health
Coding helps bridge the gap between data and action. It makes it possible to explore patterns, test ideas, build tools, automate repetitive tasks, and create ways for people to understand health information more clearly.
This portfolio reflects that broader goal. The projects here are not just technical exercises. They are attempts to make public health more visible, more understandable, and more useful.
Connect
Elsewhere on the internet
Professional updates, public health work, talks, and the more polished version of networking.
EpidemioLogical
Longer-form writing on public health, epidemiology, communication, and life outside the algorithm.
Medium
Essays, commentary, and writing that sits between analysis, reflection, and public health explanation.