Time to ‘step up’ global response to Zika outbreak

WASHINGTON – Once again, the United States is ill-prepared to handle the threat of a global pandemic entering its borders and must commit resources to the development of a Zika virus vaccine, said Dr. Victor J. Dzau, president of the National Academy of Medicine.

Dr. Dzau issued this call to action on Feb. 16 at a workshop centered around the recent Zika virus outbreak and how to combat it. The workshop was convened at the request of the Health and Human Services department.

^{Deepak Chitnis/Frontline Medical News}

Dr. Victor J. Dzau

Calling Zika virus “a new threat to global health,” Dr. Dzau said the best course of action is for the U.S. and health authorities around the world is to create a “global health risk framework” that would actively work to identify new and emerging public health threats and prevent them from becoming outbreaks. This framework would consist of a global architecture to reduce risk and mitigate the next global health crisis, identification of key resources and applications before an outbreak occurs, successful containment of future outbreaks, and coordinated responses “informed by good planning and evidence, not fear or politics,” he said.

“Global leaders need to step up,” said Dr. Dzau. “They need to step up investments to improve their response and also their preparedness for pandemics and infectious outbreaks.”

One of the most serious concerns about Zika virus has been its effects on pregnant women, as infected mothers have been bearing children with microcephaly in Central and South America. Dr. Laura E. Riley of Massachusetts General Hospital spoke about the gaps in what ob.gyns. currently know about the virus and the best way to treat pregnant women who may have been exposed.

Testing for Zika immunoglobulin M (IgM) antibodies is the “first step” in treating any pregnant woman who has traveled and may have been exposed to the virus, she said. However, Dr. Riley noted that the test is relatively new and “we’re putting a lot of stock into this test that we don’t have a lot of information about.”

Citing a Morbidity and Mortality Weekly Report released by the Centers for Disease Control and Prevention in February, Dr. Riley said that evidence of the link between Zika virus infections and microcephaly is stronger than ever, but there is still doubt as to exactly how microcephaly is caused, and at what point during the pregnancy symptoms begin to present in the fetus.

Serial ultrasounds have shown the slowing of fetal development over the course of a pregnancy – specifically in two Brazilian women examined for the report – but data is still sparse. “The causal relationship between Zika virus and other adverse pregnancy outcomes” is also of critical importance, said Dr. Riley. “I think we have pretty well established the association with microcephaly [but] there may be other neurologic abnormalities that we should be aware of and looking for.”

These other conditions include lissencephaly and intracranial calcification, Dr. Riley said.

“We don’t know what the infection rate is, but more importantly, the incidence of internal fetal transmission by trimester is particularly important as well, and what are the factors that influence that transmission?” asked Dr. Riley. “Is it the severity of internal infection? Is it the maternal immune response? We don’t know. We have information that we can glean from other infections.”

For now, said Dr. Riley is relying largely on the CDC guidance in advising patients.

“I’m taking the CDC guidance and I’m taking my own knowledge of [cytomegalovirus] and rubella and I’m trying to put it all together for Zika virus, for which I know very little,” she said.

Dr. Dzau and Dr. Riley did not report having any relevant financial disclosures.

dchitnis@frontlinemedcom.com