Based on previous experience in the USA and Italy, if the weaker H5N2 strain is present in the environment, it is likely to mutate into the stronger H5N1 strain within six months.
再說，根據早年美國和義大利的經驗，只要環境中帶有 H5N2 弱病株，不出半年，就有可能因突變而轉成 H5N1 強病株。