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By John Miller and Stephanie Nebehay
ZURICH/GENEVA, Dec 3 (Reuters) - The World Health Organization (WHO) does not recommend countries issuing "immunity passports" for those who have recovered from COVID-19, but is looking at prospects of deploying e-vaccination certificates like those it is developing with Estonia.
Estonia and the United Nations health agency in October started a pilot project for a digital vaccine certificate - a "smart yellow card" - for eventual use in interoperable healthcare data tracking and to strengthen the WHO-backed COVAX initiative to boost vaccinations in developing countries.
The reality of vaccinations is growing, since Britain on Wednesday approved a COVID-19 shot from Pfizer and Germany's BioNTech, while other companies Moderna and AstraZeneca have delivered positive trial data amid their push for approval.
"We are looking very closely into the use of technology in this COVID-19 response, one of them how we can work with member states toward an e-vaccination certificate," said Siddhartha Datta, Europe's WHO programme manager for vaccine-preventable diseases, told reporters on a call from Copenhagen.
He cautioned that any technology initiative must not overwhelm countries in the midst of pandemic responses, must conform to varying laws and ensure seamless border-crossing service.
For instance, some national COVID-19 tracing apps do not function abroad.
Estonia earlier this year separately began testing a "digital immunity passport", potentially to track those recovered from COVID-19 with some immunity, though questions remain over whether, or for how long, someone might by protected.
But another WHO official, Catherine Smallwood, the WHO's Senior Emergency Officer for Europe, on Thursday said the agency is sticking to guidance against using immunity passports as part of bids to resume some cross-border travel normalcy.
"We do not recommend immunity passports, nor do we recommend testing as a means to prevent transmission across borders," Smallwood said, urging countries instead to base travel guidance on COVID-19 transmission data.
Smallwood also said rapid antigen tests, in use by some airlines to test passengers boarding or getting off flights, may be "less appropriate" for enabling international travel. The antigen tests are less accurate than molecular PCR tests, so some people might slip through the cracks. (Reporting by Stephanie Nebehay and John Miller; Editing by Alex Richardson and Nick Macfie)
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