Johns Hopkins launches U.S. disease tracker

Johns Hopkins University has launched a new public tracker for vaccine-preventable diseases in the United States, expanding beyond its earlier measles work into a broader state-by-state and substate surveillance tool. The site was announced on August 5 and is being run with the Association of State and Territorial Health Officials and the Council of State and Territorial Epidemiologists, in partnership with state and territorial public health agencies. (hub.jhu.edu) At launch, it covers measles, invasive meningococcal disease and pertussis, better known as whooping cough. Johns Hopkins says the tracker is meant to give the public, clinicians, journalists, public health officials and policymakers a more timely and visual view of disease trends. ### So what exactly is new here? The August 5 launch turns Johns Hopkins’ disease-monitoring work into a single national-facing platform that combines interactive maps, trend views and downloadable visuals for multiple vaccine-preventable diseases. Johns Hopkins says cases are displayed in a standardized format at state and substate levels, with age-group reporting intended to show which populations are being hit hardest. The project builds on the university’s earlier measles tracker and is designed to complement, not replace, the Centers for Disease Control and Prevention’s surveillance systems. Johns Hopkins said the distinguishing feature is open-access presentation of standardized and validated public health data for broader audiences. (hub.jhu.edu) ### Which diseases does the tracker follow first? The initial list is short: measles, invasive meningococcal disease and pertussis. Johns Hopkins said other vaccine-preventable diseases will be added later. (hub.jhu.edu) The measles component comes after a sustained rise in U.S. cases. Johns Hopkins’ measles tracker was updated July 31 and showed 2,370 cases in 2026, with the site warning that outbreaks in multiple states have raised concerns about continued spread, hospitalizations, deaths and possible loss of measles elimination status. (hub.jhu.edu) Pertussis is also being added amid elevated case counts. A Johns Hopkins IVAC analysis published May 27 said the United States recorded nearly 29,000 whooping cough cases in 2025, the highest since 2012, and 16 related deaths; it said 4,598 cases had already been reported in 2026 at that point. (hub.jhu.edu) ### Where does the data come from? Johns Hopkins says participating jurisdictions voluntarily provide data for the tracker. For states not yet participating directly, the site uses data from the CDC’s National Notifiable Diseases Surveillance System. (publichealth.jhu.edu) Lauren Gardner, director of the Johns Hopkins Center for Systems Science and Engineering and a project co-lead, said the tracker’s value rests on “standardized and validated public health data.” Shaun Truelove, IVAC executive director and another co-lead, said the team designed the effort with public health partners to preserve non-identifiability and data security. (publichealth.jhu.edu) ### How broad is the rollout on day one? Ten participating states are already reflected directly in the tracker, according to Johns Hopkins. More than 25 jurisdictions have committed to join the effort, and more than 15 additional jurisdictions are set to begin participating in 2026, the university said. (publichealth.jhu.edu) The launch materials also say the tracker includes state and substate mapping across all 50 states, even as direct jurisdictional participation expands. That means the site is starting with national geographic coverage while its underlying state-supplied feeds are still being built out. That reading is based on Johns Hopkins’ description of direct participating-state data plus CDC-based coverage for non-participating states. (hub.jhu.edu) ### Why is Johns Hopkins doing this now? Johns Hopkins has spent the past two years publishing data that point to renewed vulnerability to vaccine-preventable disease. In June 2025, the university published county-level MMR vaccination data showing declines in 1,614 of 2,066 counties studied, with the average county rate falling from 93.92% before the pandemic to 91.26% after it. (hub.jhu.edu) William Moss, a senior adviser at the International Vaccine Access Center and a project co-lead, said the goal is to provide maps, figures and analyses that can help guide public health policy and help providers advise patients. (hub.jhu.edu) The next phase is already defined: Johns Hopkins says more jurisdictions and additional vaccine-preventable diseases will be added to the tracker after the August 5 launch. (hub.jhu.edu)