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  1. News Release

  2. Jun 24, 2021

Delaware Bay, Times Square Billboards Highlight the Horseshoe Crab

Doctors, Scientists Press for Nonanimal Vaccine Safety Testing Method

MILFORD, Del.—The Physicians Committee for Responsible Medicine—a national nonprofit of physicians and scientists—is calling for the replacement of horseshoe crab blood with a nonanimal reagent for vaccine safety testing, with billboards in Delaware Bay and Times Square and a corresponding informative video. 

At present, testing vaccines for bacterial contamination typically uses reagents sourced from the blood of horseshoe crabs; many crabs die following the extraction process, and the species is considered vulnerable by the International Union for Conservation of Nature. A nonanimal, synthetic option called recombinant factor C, or rFC, is shown to be scientifically superior. 

Horseshoe crab spawning season on the Atlantic coast peaks this month, with thousands of crabs flocking to the sandy beaches of Delaware Bay to lay 100,000 or more eggs per crab. Two billboards from the Physicians Committee, located near the bay, in Milford, Del., feature a peaceful image of a horseshoe crab on a beach and direct readers to The ads point out why the synthetic vaccine safety testing option surpasses the reagent derived from horseshoe crab blood: It’s safe, effective, animal-free, and reliably available. 

At the same time, in New York’s Times Square, an animated, wraparound ad five stories above the intersection of West 43rd Street and Broadway shows horseshoe crabs in their natural environment, with gentle waves washing over them. The text reports that many horseshoe crabs die after their blood is extracted for vaccine safety testing but that there is a synthetic option—and it’s better. 

The organization has also released an informative 2-minute video further explaining the details of the issue, noting that reliance on the blood of an animal species for vaccine and injectable therapy production goes along with a risk of supply disruption. The rFC reagent has already been successfully employed to test injectable therapies, but outdated regulatory policies make it difficult to use. 

“rFC holds advantages over the horseshoe crab blood test that can help safeguard vaccine supply,” says Elizabeth Baker, Esq., regulatory policy director for the Physicians Committee. “It is time to bring policy in line with science by removing regulatory hurdles to its use.”

To speak with Ms. Baker or to see the video or ads, please contact Reina Pohl at 202-527-7326 or rpohl [at]

How Vaccine Safety Testing Hurts Horseshoe Crabs—And Why It Doesn't Have To

Media Contact

Reina Pohl, MPH



Founded in 1985, the Physicians Committee for Responsible Medicine is a nonprofit organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in education and research.

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