https://jewishaction.com/religion/jewish-law/zika-in-halacha/
To give us a sense of the magnitude of the epidemic, according to an account from the rabbinic court of Rav Shmuel Vozner (1913-2015), over 1,000 cases were presented to the court requesting abortion. The court prohibited abortion in every single case (consistent with the general approach of Rabbi Feinstein). As a postscript, it is further reported that in all the cases, save one, no harm befell the subsequent children. As this is an anecdotal account, absent any details of the cases, we cannot know whether the women had confirmed cases of rubella, and if so, during which trimester. In any case it is a remarkable number.