HUGE VICTORY! CDC to End All Its Monkey Experiments

Update (November 21, 2025): HUGE VICTORY! In a seismic win for animals and science, the U.S. Centers for Disease Control and Prevention has announced that it will phase out cruel experiments on monkeys in its laboratory—a long-overdue move that PETA has fought for relentlessly. PETA is thanking the administration for taking this decisive, visionary step and acknowledging what mountains of evidence have made clear: Experiments on monkeys aren’t delivering for humans, nowhere more obvious than the four-decade failure to produce a marketable HIV vaccine. Today, we’re celebrating a historic turning point—one that protects public health, respects endangered species, and helps propel research into a modern, animal-free future.

Update: Tom Frieden—who was the director of the Centers for Disease Control and Prevention (CDC) when egregious incidents of neglect and incompetence took place that resulted in the suffering and death of monkeys, prairie dogs, mice, and other animals—has just been charged with third-degree sexual abuse, forcible touching, and harassment of a woman. Is it any wonder that someone who, for a long time, was giving vivisectors the green light to conduct horrific experiments on complex individuals and treat them as nothing more than walking test tubes would have trouble respecting the rights of another member of his own species?

Frieden is being forced to deal with these allegations, but he has yet to answer for a long list of atrocities committed at the CDC under his watch. These include incidents in which monkeys sustained third-degree burns over their arms and backs, prairie dogs died after becoming stuck in a floor drain, and mice were painfully asphyxiated after the ventilation pump to their enclosure was turned off.

The Centers for Disease Control and Prevention (CDC)—which imprisons thousands of animals—has a long history of violating federal animal welfare laws and guidelines. Not long ago, PETA released disturbing leaked photos of monkeys at CDC labs who suffered third-degree burns over their arms and backs as a result of incompetence and negligence. We obtained documents showing, among other abuses, that when CDC employees failed to monitor an owl monkey who had undergone experimental surgery, the distressed monkey pulled out the sutures and her intestines spilled out of the wound. Eventually, she stopped breathing.

Now, PETA has received more government reports documenting glaring incompetence and gross mistreatment in the CDC’s laboratories—leading to immense suffering and cruel deaths for animals, including incidents in which:

• Fifteen mice died or had to be euthanized after they were placed in cages that were still hot from high-temperature sterilization equipment. The mice were reported as showing “increased salivation” and “signs of distress due to hyperthermia.”
• A calf died of hypothermia in a barn that was known to have a malfunctioning heater.
• A pigtail macaque monkey was either inadvertently inoculated with simian-human immunodeficiency or acquired the infection from a positive animal. It was not known which.
• On two separate occasions, prairie dogs died after becoming stuck in an unsecured floor drain.
• Five mice died painfully of asphyxiation after the ventilation pump to their enclosure was turned off.
• Two ferrets and 40 mice were inoculated with an H9N2 virus, which was later confirmed to be contaminated with the highly contagious H5N1 bird flu virus. The animals were all killed.
• During a viral study using embryonated eggs, 17 eggs were inadvertently allowed to hatch. All of the chicks were killed.

The new revelations follow more than a decade of documented problems of abuse, neglect, and incompetence in the CDC’s laboratories. The CDC has an annual budget that exceeds $6 billion, with more than $500 million earmarked for “monitoring health and ensuring laboratory excellence.” In contrast to other laboratories that use animals covered under federal regulations, government laboratories—like those operated by the CDC—are not subject to federal inspections. The CDC’s lack of accountability has resulted in egregious suffering for animals and perilous working conditions for employees.