The Food and Drug Administration directed the strict screening of donated bloods and their donors in view of the proliferation of the Zika virus in the United States.

Considered as among the biggest health scares in history, the Zika pathogens post hazards to pregnant women and their unborn children.

It instructed all U.S. states and territories to screen individual units of donated blood and blood components through screening procedures from authorized FDA establishments.

The FDA updated its guidance after careful consideration of all available scientific evidence, consultation with other public health agencies, and the serious threat of Zika virus to pregnant women and their unborn children.

Testing of donated blood is already underway in Florida and Puerto Rico.

Expanded testing will continue to reduce the risk of Zika virus transmission. The directive will be in effect until the menace of Zika virus is reduced or eliminated, according to the FDA.

However, the FDA clarified that only donors in areas where Zika virus are reported shall undergo series of blood screening tests. It also directed all blood banks to source their supplies from areas without reported Zika incidents. 

"As new scientific and epidemiological information regarding Zika virus has become available, it's clear that additional precautionary measures are necessary," said Luciano Borio, chief scientist of FDA.