Measles Vaccine Impact, Tracking Narco-Submarines, Portugal’s Electoral Shift, and a Mission to Saturn’s Moon

The last few weeks have been quieter for data journalism. Instead of one or two major news items dominating visualizations, a wide variety of topics were covered, such as an analysis of the impact of measles vaccination since its introduction in the 1960s and an investigation into the narco-submarines that transport cocaine across the Atlantic and Pacific Oceans. This edition of our Top 10 in Data Journalism, which considered stories between May 10 and May 23, also highlights a special report on the fate of Jews from the Polish city of Lubartów during World War II; an examination of the number of plane crashes in the US; an investigation into an ambitious reforestation program in the Philippines; and the list of Sigma Awards winners.

Impact of Measles Vaccine

Image: Screenshot, Our World in Data

Measles has made a comeback in doctors’ offices and in headlines, with countries around the world seeing a rapid increase in cases. In this report, Our World in Data discussed the history and impact of vaccines against measles — a highly contagious disease that was once widespread, affecting more than 90% of children just 60 years ago. The first effective vaccine was developed in 1963, and vaccination rates have increased significantly since then — first in wealthier countries and then worldwide in the 1970s and 1980s. According to the report, the impact of measles vaccination was rapid and substantial, with an estimated two to three million deaths each year prevented over the past half century, making measles vaccines among the most life-saving vaccines currently in use.

Underwater Cocaine Trafficking

Image: Screenshot, InSight Crime

In 2024, authorities intercepted a near-record number of so-called narco-submarines crossing the Atlantic and Pacific Oceans. To understand what the increasing use of these vessels says about drug trafficking routes and criminal dynamics, InSight Crime analyzed hundreds of these seizures. According to the report, these vessels have been around for decades and are traditionally used to transport drugs from the Pacific coast of Colombia to Central America or Mexico, but are now expanding to new areas, such as the Azores, Sierra Leone, and even Australia. Graphs show, for example, the increase in the number of narco-submarine seizures between 1988 and 2025 and a map of them, and illustrations of the different types of vessels used on trafficking routes. According to the report, traffickers are constantly adapting their vessels to avoid interception.

History of Lubartów’s Jewish People 

Image: Screenshot, WeDoData

Designed by French dataviz agency WeDoData, the scrollytelling special, Visualizing Lubartworld, traced the “collective biography” of the Jewish population in the Polish village of Lubartów throughout the 20th century. It presented the results of the Lubartworld project, led by the French National Centre for Scientific Research (CNRS) and the School for Advanced Studies in the Social Sciences (EHESS). The report us divided into three chapters and throughout the narrative, it is possible to see historical documents and photographs that illustrate and corroborate the story: The first presents a portrait of the population of Lubartów in the 1930s — where less than 8,000 Jewish and Catholic inhabitants lived — through maps, network graphs, photographs and animations; the second chapter tells the story of the various displacements of the village’s Jewish population — around 3,400 people — before and during World War II until only 18 Jews remained in the region; and the third and final chapter features an animation based on a 3D globe with a timeline, which tells the story of the migration flows of the population of Lubartów to the rest of the world during the 20th century.

Eurovision Numbers

A Tagesanzeiger analysis found that Eastern European countries awards performers from their own region the most points in the Eurovision Song Contest. Image: Screenshot, Tagesanzeiger

Held annually since 1956, the Eurovision Song Contest (ESC) is one of the most eagerly awaited music events for European audiences each year. This year alone, 166 million people watched the competition — held in Basel, Switzerland — on television. Shortly before the final on May 17, the Swiss daily Tagesanzeiger ran a special report analyzing the event’s numbers. A series of graphs showed, for example, that the number of participants is decreasing due to finances, politics, and war; “block voting” occurs between countries that are historically, politically, culturally, or linguistically linked; and also how the competition’s points system works. The team also reflects on what makes a song a winner, through an analysis of the attributes used by the streaming service Spotify to characterize songs. The report also says that Ireland and Sweden are the two nations that have won the ESC most often — seven times each.

Is Flying Becoming More Dangerous?

Image: Screenshot, CNN

In this special report, CNN examined commercial aviation safety in the United States, citing a series of recent incidents that have raised concerns among travelers — notably the January 2024 crash in Washington, DC, in which 67 people died in a collision between an American Airlines plane and a Black Hawk helicopter. The team analyzed all aviation investigations conducted by the National Transportation Safety Board (NTSB) from January 2000 to March 2025, which included accidents with injuries, fatalities, or major damage, and asserts that flying has never been safer. According to the report, between January 2024 and March 2025, there were only 60 incidents involving commercial carriers, with two resulting in fatalities — including the accident in the US capital. Before that, the last major collision was in 2009. It also featured data on near-misses involving high-profile aircraft and data from the Department of Transportation on the share of fatalities in the US by mode of transportation from 1990 to 2022 — which showed how much safer flying is than driving.

Mission to Reach One of Saturn’s Moons

Image: Screenshot, USA Today

Dragonfly is the name of a NASA mission planned to study Titan, one of Saturn’s 274 moons. Titan has long fascinated scientists because, within our solar system, it has the atmosphere most similar to Earth’s. To reach the moon’s surface, NASA plans to use an eight-rotor probe, similar to a drone, that recently completed a crucial test. Through a series of illustrations, USA Today explained in detail the mission planned for launch in 2028, which has faced several delays and budget overruns. According to NASA, the probe has a total life cycle cost of US$ 3.35 billion.

Reforestation Failure in the Philippines

Image: Screenshot, Davao Today

The Philippines’ National Greening Program (NGP) is considered the country’s most ambitious reforestation program to date, hoping to preserve the rainforest and promote sustainable agriculture by planting 1.8 billion trees across more than 2 million hectares of public lands devastated by decades of rampant logging. But 14 years after its launch, an investigation by DavaoToday, Thibi, and Lighthouse Reports showed how the program has failed on both counts. The team used machine learning tools to analyze millions of satellite images and detect deforestation at more than 100,000 NGP sites, analyzed official government data on program spending and the status of reforestation sites, and conducted interviews with whistleblowers. Among the report’s findings: one in every 25 hectares of NGP land has suffered major deforestation rather than reforestation, with many of the areas designated as protected having no trees at all, let alone thriving rainforests of native species.

Effects of New York City’s Congestion Zone Policy

Image: Screenshot, The New York Times

On January 5, New York City implemented a congestion zone system for the lower third of Manhattan, similar to those already been adopted by major cities such as London, Milan, and Gothenburg. This system charges additional tolls for vehicles entering the area at busier times of day to reduce traffic and fund public transportation. According to The New York Times, almost immediately after it was implemented, the policy began to alter traffic patterns, passenger behavior, public transportation, and city noise. Using maps and animations, the Times showed that, compared to a year earlier, 80,000 fewer cars per day were entering lower Manhattan; 15% fewer car accidents with injuries occurred; local bus lines ran about 3.5% faster, with some routes seeing an increase of up to 28%; and complaints about vehicle noise and fines have fallen by nearly half.

Portugal’s Electoral Trends

Image: Screenshot, Público

In this special report, the Portuguese newspaper Público analogized electoral voting trends to shifting winds to analyze Portugal’s political map after its legislative elections on May 18. The scrollytelling report presented a series of interactive maps with arrows indicating the growth that political parties have had in relation to the last election. According to the data, the 2024 trend continued this year too, as Portugal’s voters leaned even further to the right, with the populist right-wing party Chega — described in the report as a hurricane — becoming the second largest political force in the country. The newspaper also described the center-right Democratic Alliance as a current: it was the most-voted-for party, electing 88 deputies. According to the report, the biggest losers on election night were the Socialist Party (PS), which came in third, and the Left Bloc (BE), which won only one seat in the Assembly of the Republic.

Looming Threats to the Insurance Industry

Image: Screenshot, Moody’s

In the months right before wildfires consumed large swaths of the Los Angeles metropolitan area, many insurers had canceled large numbers of local policies. In this report, Moody’s presented 10 potential major risks that are changing the insurance industry. Charts show the age of condominium units in Florida to note that “paradise” is now located in ever more risky places; a map of major floods since 2011 that have significantly disrupted supply chains; a network diagram of the transmission of H5N1 (avian flu); and a heatmap of wildfire risks in the US and active fire locations around the world monthly since May 2024. In addition to these potential risks, the report also lists flash flooding caused by increasing heavy rainfall, IT outages, building collapses, and contamination by forever chemicals (PFAS) and microplastics.

Bonus: Sigma Awards Winners Announced

Image: GIJN

The Sigma Awards — a competition celebrating the world’s best data journalism now hosted by GIJN — has announced its 2025 winners. Ten data-driven journalism projects were selected from 498 entries from 80 countries by a Prize Committee of 17 judges. Check out the award winners, which include stories that have exposed the impact of violence against authorities on public life in Mexico; the recruitment of prisoners for a mercenary army in Russia’s war in Ukraine; and a land trafficking scheme by organized crime syndicates in Ecuador — and be inspired!

Ana Beatriz Assam is GIJN’s Portuguese editor and a Brazilian journalist. She has worked as a freelance reporter for the newspaper O Estado de São Paulo, mainly covering stories featuring data journalism. She has also worked for the Brazilian Association of Investigative Journalism (Abraji) as an assistant coordinator of journalism courses.