The US Department of Health and Human Services (DHHS) has declared that a strain of enterovirus now sweeping across the US has a high potential to cause a "public health emergency," thereby allowing the US Food and Drug Administration (FDA) to clear the use of drugs and diagnostic devices under special "emergency use" regulatory pathways.

According to the US Centers for Disease Control and Prevention (CDC), the virus, known as enterovirus D68, is one of more than 100 non-polio enteroviruses. The virus disproportionately affects infants, children and teenagers, and can cause severe respiratory illness.

While the virus has been present in the US since at least 1987, a 2014 outbreak of the virus "was much greater than [outbreaks] reported in previous years," explained CDC on its website.

New Authority

Unlike in past years, however, US healthcare officials have a new suite of regulatory tools they can use to confront the outbreak.

In March 2013, FDA was given a host of new authorities and responsibilities under the Pandemic and All-Hazards Preparedness Reauthorization Act (PAHPRA), a piece of legislation meant to bolster the government's ability to respond to health crises, and especially those of a biological nature.

Among the law's many provisions is one that allows FDA to temporarily approve a medical product if it determines that an emergency is likely to occur—a "threat justifying emergency authorized use," to quote the legislation. Previously, FDA was only permitted to approve products on an emergency basis if a public health emergency was already present.

The law also allows FDA to approve those products without first ensuring that they meet current good manufacturing practice (CGMP) regulations.

The bill was signed into law on 4 March 2013 by President Barack Obama, and received overwhelming bipartisan support during its passage through Congress.

Since then, DHHS has declared that several diseases pose "a significant potential to affect national security or the health and security of United States citizens living abroad." For example, DHHS has declared that the H7N9 influenza virus, the Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and the Ebola virus all represent threats to the US.

DHHS's declarations aren't just symbolic. Once a threat is declared by DHHS, FDA is then legally permitted to fast-track the authorization of new medical products under its emergency use authorization (EUA) provisions.

For example, FDA has already authorized the use of eight diagnostic tests meant to make it easier to diagnose patients suspected to have the Ebola virus. The agency has also authorized the use of three diagnostics for the H7N9 influenza virus, and one diagnostic for MERS-CoV. A standing EUA also covers the use of doxycycline to treat anthrax after suspected exposure.

Measures to Impact Enterovirus D68

Now, FDA will be permitted to take similar measures to help confront Enterovirus D68.

An early candidate for authorization is likely to be a diagnostic test developed by CDC and already in use by the agency. CDC's test reportedly allows for the diagnosis of the test "within a few days of receiving specimens).

It will therefore be up to FDA to determine whether CDC's test—and other tests—are sufficiently accurate to warrant emergency use authorization. If granted EUA, each test would be exempt from normal premarket regulatory requirements, but would need to accompany each device with specific labeling indicating that the device has not yet been granted approval.

There are currently no antiviral medications approved for use to treat the virus, CDC says.

Determination and Declaration Regarding Emergency Use of New In Vitro Diagnostics for Detection of Enterovirus D68