day 24 WHO

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Published

April 24, 2025

The prompt for Day 24 is the World Health Organisation. I spent some time exploring the WHO website for a chart that uses a geom that I hadn’t tried before and came up with this one from the World Health Statistics 2024 report.

I found a table of the data in the Global Hepatitis Report 2024 and used this Rscript to get it into csv format.

library(tidyverse)
library(here)
library(janitor)
library(treemapify)
library(ggeasy)
library(patchwork)
library(ggtext)

hep <- read_csv(here("charts", "2025-04-24_who", "hepBC.csv"))

glimpse(hep)

Rows: 6
Columns: 5
$ WHO_region  <chr> "African Region", "Region of the Americas", "South-East As…
$ new_hepB    <dbl> 771000, 8000, 266000, 18000, 86000, 83000
$ new_hepC    <dbl> 172000, 176000, 225000, 126000, 183000, 98000
$ deaths_hepB <dbl> 272000, 20000, 218000, 32000, 41000, 518000
$ deaths_hebC <dbl> 35000, 38000, 42000, 21000, 65000, 43000

what kind of plot?

Now I don’t even know what this kind of chart is called, let alone how to make it with ggplot, so I asked claude.ai for some suggestions.

claude’s code

I was surprised that the code that claude wrote ran without throwing an error and made a passable treemap plot. It is actually impressive that the LLM pulled the data and colour palette from the png file I gave it. Of course, if I want to learn about how treemaps work, I should probably start from scratch.

source(here::here("charts", "2025-04-24_who", "claudes_code.R"))

final_plot

my code

hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region)) +
  geom_treemap()

Basic plot check! Things I would like to change…

colour scheme
labels on the boxes
titles, captions
layout (how do I get the large African Region box to appear on the top, rather than left)

colours

It is interesting that the colours that claude used in his code are close but not exactly the same as the ones I pulled from the plot using the ColorZilla tool.

claudes_colors <- c(
  "African Region" = "#5EB3D5", "South-East Asia Region" = "#A9D18E",
  "Eastern Mediterranean Region" = "#F6B18F", "Western Pacific Region" = "#FFD966",
  "European Region" = "#C293CE", "Region of the Americas" = "#A593C7"
)

palette <- c("African Region" ="#69C1E6",  "South-East Asia Region" = "#B5D47C", 
                 "Eastern Mediterranean Region" = "#F3A078",  
               "Western Pacific Region" =  "#FACF70",
                 "European Region" ="#CC71B2", "Region of the Americas" ="#A687B6")

OK here I have sorted the colour palette and added I fine white line between the boxes using colour = “white”. Next labels…

hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region)) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette)

labels

hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region, 
             label = paste(WHO_region, new_hepB, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend()

layout

note it doesn’t seem possible to control the layout of the boxes using the treemapify package; I played with the layout argument which has “squarified” as the default but allows you to specific layout = “srow” which forces the tile placement to begin with a row… it didn’t seem to do anything.

hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region, layout = "srow",
             label = paste(WHO_region, new_hepB, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend()

titles / captions

I am going to make an equivalent HepC plot and then paste them together before adding chart titles and captions. Using the layout = “fixed” option allow a side by side comparison of the HepB and HepC plots

hepB <- hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region, layout = "fixed",
             label = paste(WHO_region, new_hepB, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend() +
  labs(title = "Figure 2.4 Number of new hepatitis B and hepatitis C infections, by WHO region, 2022", subtitle = "Hepatitis B") +
  theme(plot.subtitle = element_text(hjust = 0.5, size = 5), 
        plot.title = element_text(size = 10)) 



 hepC <- hep %>% 
  ggplot(aes(area = new_hepC, fill = WHO_region, layout = "fixed",
             label = paste(WHO_region, new_hepC, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend() +
  labs(subtitle = "Hepatitis C") +
   theme(plot.subtitle = element_text(hjust = 0.5, size = 5))

 
 hepB  + hepC

And lastly, claude helped get the yellow/bold formatting for the title. The ggtext package is required to allow for element_markdown()

hepB <- hep %>% 
  ggplot(aes(area = new_hepB, fill = WHO_region, layout = "fixed",
             label = paste(WHO_region, new_hepB, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend() +
labs(title = "<span style='color:#F4BD4B;'>Figure 2.4</span><span> Number of new hepatitis B and hepatitis C infections, by WHO region, 2022</span>", 
     subtitle = "Hepatitis B") +
  theme(plot.subtitle = element_text(hjust = 0.5, size = 5), 
        plot.title = element_markdown(hjust = 0, size = 8, face = "bold"))

 hepC <- hep %>% 
  ggplot(aes(area = new_hepC, fill = WHO_region, layout = "fixed",
             label = paste(WHO_region, new_hepC, sep = "\n"))) +
  geom_treemap(colour = "white") +
  scale_fill_manual(values = palette) +
  geom_treemap_text(colour = "black",
                    place = "topleft",
                    size = 5, 
                    grow = FALSE) + # option from ggfittext to NOT make font fit box
  easy_remove_legend() +
  labs(subtitle = "Hepatitis C") +
   theme(plot.subtitle = element_text(hjust = 0.5, size = 5))

 
 hepB  + hepC