In a milestone move, the United States Food and Drug Administration approves the first ever drug that treats the infectious and potentially lethal smallpox disease.

Smallpox has actually been declared as eradicated as far back as 1980, but the disease remains a threat due to the concerns of the virus being used as a biological weapon.

FDA Approves Smallpox Drug

On Friday, July 13, the FDA announced the approval of the drug tecovirimat or TPOXX, which was deemed effective following successful trials on animals infected with viruses related to the one that causes smallpox.

The newly approved drug's safety was established with tests on healthy human volunteers who reported side effects that include headache, nausea, and abdominal pain.

Even with the elimination of naturally occurring smallpox, the Congress made it a priority to find solutions for pathogens that could be used as weapons.

"This new treatment affords us an additional option should smallpox ever be used as a bioweapon," Scott Gottlieb, M.D, the FDA commissioner, says in a statement. "This is the first product to be awarded a Material Threat Medical Countermeasure priority review voucher. Today's action reflects the FDA's commitment to ensuring that the U.S. is prepared for any public health emergency with timely, safe and effective medical products."

Smallpox And Bioterrorism

Smallpox emerged thousands of years ago, plaguing populations around the world with severe illness and death, the Centers for Disease Control and Prevention reports. Highly contagious, it is caused by the variola virus. Symptoms include fever and a distinctive rash that spreads all over the body.

The majority of people who catch the infection recover, but many are left with large scars from the rash. There are those who become blind from the infection. Three out of 10 people with smallpox died.

It's a potentially fatal disease on its own, but what makes smallpox even more terrifying is the prospect of it being used as a bioweapon.

While the last naturally occurring smallpox was back in 1977, CDC says that it has been used historically by people to infect their enemies.

Only the CDC and the Russian State Centre for Research on Virology and Biotechnology in the Russian Federation are approved to have the smallpox virus for research. However, there have been credible concerns that some countries used it to create bioweapons. If these creations somehow get to the hands of terrorists, it could prove to be extremely dangerous worldwide.