The high transmission rates in areas such as New York are worrying, says Mark Lipsitch, an epidemiologist of the Harvard School of Public Health in Boston, Massachusetts.

• 哈佛大学公共卫生学院的一位流行病学家MarkLipsitch指出：“在诸如纽约这样地区的病毒高传染率是十分令人担忧的”。