Avian flu ?

Bird flu also killed 12 people in Thailand last year, but no new cases have been reported there since November.
The World Health Organization warned Vietnam may face new bird flu cases this month as poultry is moved around the country ahead of the Lunar New Year celebrations.
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The transporting activities plus the migrating birds are the factors that may cause new type of virus. How to minimise the 'mix around' and prevent or delay infectious viral attack? I am sure you are wise and know the answer.