1·It remains to be seen whether the virus will mutate into a more virulent strain.
该病毒是否会产生变异，成为毒性更强的病毒株，仍有等观察。
2·Having sequenced the new strain's genes, the researchers recreated it in a laboratory and exposed it to pigs. The strain proved contagious but only mildly virulent.
按顺序排好新菌株的基因，研究人员在实验室中重新构建了它，并把它与猪相接触。证明了该菌株会蔓延的，但只有轻微的毒性。
3·Studies have detected no signs that the virus has mutated to a more virulent or lethal form.
经研究未发现迹象说明病毒已突变为更具毒性或更致命的形式。
4·The strain proved contagious but only mildly virulent.
证明了该菌株会蔓延的，但只有轻微的毒性。
5·Fortunately, the strain was far less virulent than originally feared, killing about 19,000 people.
幸运的是，这种菌株的毒性远远小于人们原先所担心的，但也造成了约19,000人死亡。
1·Now he faces virulent attacks from the Italian media.
现在他面临着意大利媒体的恶毒攻击。
—— 《柯林斯英汉双解大词典》
2·Such infections appear to be more virulent and more easily spread between people than earlier strains.
这类感染似乎比较早出现的菌种更恶毒，并更容易在人们之间蔓延。
3·Then we knew that this was to be expected too; as if that quality of her father which had thwarted her woman's life so many times had been too virulent and too furious to die.
我们明白这也并非出乎意料；她父亲的性格三番五次地使她那作为女性的一生平添波折，而这种性格仿佛太恶毒，太狂暴，还不肯消失似的。
4·Like any virulent conspiracy theory, that of Obama's birth has proved immune to the intervention of fact.
如同任何恶毒的阴谋论，奥巴马的出生已证明是不争的事实。
5·However, H5N1 has infected increasing Numbers of people in the past 3 years, and is becoming more virulent as it evolves.
虽然禽流感感染人的数字在过去3年不断上升，但是它却变得更加的恶毒。
1·Hermillia Villegas, a 47-year-old mother of two in Jalisco, Mexico, recently learned that she had a virulent form of breast cancer that responded well to treatment with Herceptin.
赫尔米拉·比列加斯是位两个孩子的母亲，今年47岁，住在墨西哥哈利斯科州。她最近获悉自己得了一种恶性乳腺癌，目前使用赫赛丁效果很好。
2·All of a sudden, a lot of well-maintained old cars, especially sportier models, have begun to fail in surprising numbers-as if struck down by some virulent new disease.
许多修了又修的老爷车，尤其是运动型跑车，刹那间销声匿迹了，数量之众让人称奇，就好像全都被某种新型恶性传染病夺去了生命。
3·In Belgium and the Netherlands, a virulent new strain of avian flu was wiping out entire chicken farms.
在比利时和荷兰，一种新的恶性的禽流感病毒株系席卷了所有的养鸡场。
4·After 14 months, the defining characteristic of this financial crisis has been its tendency to change shape and return in ever more virulent form.
14个月之后，危机开始扩大规模并进入更恶性的阶段。
5·Now experts fear a virulent fungus could decimate the few thousand frogs they estimate survive.
如今，专家们担心有一种恶性真菌可能会毁灭被他们认为存活的几千只山鸡蛙。