Friday, April 8, 2016

Zika virus isolated from fetal brain tissue

Cheng-Ying Ho, MD, PhD
Dr. Cheng-Ying Ho, neuropathologist at Children's National Medical Center in Washington DC, recently authored a report in the New England Journal of Medicine entitled Zika Virus Infection with Prolonged Maternal Viremia and Fetal Brain Abnormalities. In this report, Dr. Ho and colleagues describe a case of a pregnant woman and her fetus infected with the Zika virus during the eleventh week of gestation. The fetus had a significantly decreased head circumference by the twentieth week of gestation. Given the grave prognosis, the mother elected to terminate the pregnancy at 21-weeks gestation. Postmortem analysis of the fetal brain revealed diffuse cerebral cortical thinning, a high Zika virus RNA load, detection of viral particles, and isolation of the Zika virus from brain tissue. This is the first report of Zika virus isolation from fetal brain tissue. This finding fulfills Koch's second postulate regarding the isolation of a pathogen from a diseased organism and therefore goes a long way toward strengthening the association between congential Zika virus infection and fetal brain damage. This is an important work from a rising star in the neuropathological firmament. As a fellow neuropathologist commented, Dr. Ho is "a very talented young investigator from whom you will be hearing a lot in the future".

3 comments:

Ian M Mackay said...

An important item to identify is whether, and if so how often, this virus can be found in non-diseased tissue

Brian E. Moore, MD, MEd said...

Good point, Ian. I'll inquire with Dr. Ho regarding your question and post her response.

Cheng-Ying Ho said...

Dear Ian, In this particular case, virus was detected at very low level in "morphologically normal" organs by RT-PCR. The "morphologically normal" nervous tissue such as dorsal root ganglia is negative for virus by immunofluorescent staining.