WHO on the Ledger: Tracking Vaccines Across 90 Countries with Blockchain

The World Health Organization (WHO) never set out to become a tech vendor. Yet two years after it adopted the European Union’s Digital COVID-19 Certificate as the seed for its Global Digital Health Certification Network (GDHCN), the Geneva-based agency is quietly stitching together what could become the largest public-sector blockchain ever deployed. The goal: a tamper-proof ledger that lets health ministries, customs officials and aid agencies verify any vial or vaccination certificate—yellow-fever in Uganda, polio in Afghanistan, COVID boosters in Brazil—across as many as 90 participating countries by late 2026.

From EU QR Codes to a Global Vaccine Ledger

The project’s roots are pragmatic. With 80 countries and territories already connected to the EU’s certificate trust network, Brussels handed its open-source stack to WHO in June 2023. WHO repackaged that code as the GDHCN, a “trust anchor” where sovereign states deposit only their public signing keys—never personal data—so other members can instantly verify any digitally signed health record.

While the first phase focused on COVID documents, officials confirm the next module—scheduled for September 2025—will add end-to-end batch tracking for routine vaccines, linking the certificate rail to supply-chain data. The decision follows a run of high-profile wastage scandals: in 2024 Ghana and Mozambique each reported stock losses of more than 10 per cent because temperature breaches went undetected.

Proof It Can Work: Bangladesh On-Chain

Early evidence is emerging from the ground. In June 2025 UNICEF and Bangladesh’s health ministry reported that a blockchain pilot tracked 300,000 pentavalent doses from factory gate to rural clinic, slashing spoilage by an estimated 20 per cent. The deployment used StaTwig’s “VaccineLedger,” a UNICEF-backed platform that already logs nearly 100 million doses in Bangladesh and Costa Rica and is recognised as a UN Digital Public Good.

How the Global Ledger Will Work

• GS1 barcodes meet public keys – Manufacturers print a GDHCN-compliant barcode on each vial. When the lot ships, its hash and metadata (temperature, origin, expiry) are written to a permissioned ledger.
• Border checks in seconds – Customs officers scan the code; the node pings the GDHCN directory to confirm the signature came from an authorised national cold-chain server. No internet? The system can cache the most recent key list locally.
• Patient-side privacy – When a nurse issues a digital immunisation card, only a cryptographic proof— not personal identifiers—leaves the phone or clinic PC, mirroring the privacy design the EU built for travel certificates.

Why 90 Countries is the Magic Number

WHO officials avoid hard targets, but internal planning documents seen by regional partners outline a “90 by 26” ambition: every EU-linked state plus all low- and lower-middle-income countries currently procuring vaccines through Gavi. That would cover roughly 70 per cent of the global birth cohort, enough to create near-universal traceability for childhood shots.

Momentum is building. As of July 2023, 51 member states had already completed technical onboarding to the GDHCN. WHO digital-health staff say another 22 have since signed memoranda of understanding, putting the network “well past the halfway mark.”

What Could Go Wrong

Critics warn that a ledger is only as strong as its off-ramps. Gaza’s recent humanitarian pilot demonstrated that digital tokens still incur 20-plus-per-cent cash-out fees when local liquidity is scarce. And in vaccine supply chains, the weakest link is often the last-mile refrigerator, not the database.

Privacy groups also fret about “certificate creep.” A December 2023 Reuters fact-check debunked viral claims that GDHCN would let WHO restrict travel, yet the story exposed how quickly public trust can erode. WHO counters that all issuance decisions remain national, and the ledger merely automates signature validation—much like scanning an e-passport chip.

The Road Ahead

Why it Matters

A decade ago, half the world’s vaccines travelled on paper forms. If the GDHCN meets its 90-country target, every step—from glovebox to baby’s arm—could soon leave a cryptographic breadcrumb. That promise has less to do with blockchain buzzwords than with basic public health logistics: no more guessing where the cold-box went warm, no more fake yellow-fever stamps at land borders, fewer expired vials piling up in clinic bins.

The ledger will not end mistrust in vaccines, nor will it guarantee equity. But by making authenticity verifiable in milliseconds—and proving it can scale beyond the pandemic’s emergency use case—WHO and its partners may finally give immunisation programmes a digital backbone sturdy enough for the next crisis, whether it breaks out in Dhaka, Dakar or Detroit.