MEDICAL: Similarity versus Reality—- The Bilibid Prison Vaccination Saga – By Yvonne Sam

 By Yvonne Sam

An unethical vaccine experiment that went horribly wrong but was swept under the rug

On November 18, 1906, Richard P. Strong, the Director of the Bureau of Laboratories at Bilibid Prison in the Philippines inoculated 24 inmates with a serum against cholera. Not only did the vaccines grant a relatively short period of immunity—a maximum of fourteen months, but was clearly indicated only when there was a clear threat of cholera to the patient.

For over two months there had been no cholera in the prison, and there was absolutely no reason to expect the disease to recur in the upcoming months. The inmates were not told what was inside the syringe, and those who resisted the injection were urged on by prison guards.   

Strong wanted to test the side effects of a popular cholera vaccine, and was not particularly devoted in protecting the health of his subjects, but was hoping to prove instead that his own vaccine was more efficacious than others.

Three days following administration of the vaccination, two of the inoculated inmates fell ill an died. Autopsies suggested an unexpected culprit: the bubonic plague. By the time the disease had run its course, thirteen of the twenty-four inmates were dead.

Speculation that a visiting doctor must have inadvertently gotten the plague tube mixed with the cholera vaccines came from Dr. Paul Freer, the immediate supervisor of Dr. Strong. In a confidential letter written to a friend, he recapitulates that a tube containin g virulent plague bacteria became missing from the laboratory of Dr. Strong, who on noticing its absence , issued a search. An empty tube was later discovered discarded in a cleaning solution and the doctor thought no more of the matter, believing that all was cleared up.

Although Freer was Strong’s superior he only became aware of the inoculation experiment after the prisoners started becoming ill. He received a telephone call notifying him that “two men whom Strong had inoculated were very sick in Bilibid; that one was likely to die and that he (Freer) had better get hold of Strong.” Attempting to keep the incident quiet was, in Freer’s words, “the hardest blizzard we have ever experienced.” The Philippine Governor-General appointed two committees to investigate the actions of Dr. Strong. After review, it was “generally agreed that Strong had not intentionally inoculated the prisoners with the contaminated vaccine,” writes physician Kristine Campbell, in a journal article titled Knots in the Fabric: Richard Pearson Strong and the Bilibid Prison Vaccine Trials, 1905-1906

Although the Senate, the secretary of war, and even the President were kept informed of developments, no mainland investigations ensued. The general committee concluded that Strong was negligent for not having locks on his incubators and for leaving a visiting physician alone in the laboratory, where he might have mixed up the cholera and plague cultures on the fateful day.

The committee’s charge was referred to the attorney general, who found Strong innocent of criminal negligence, whereupon the governor-general exonerated Strong. Strong himself published nothing about the incident in Bilibid prison. Freer’s only public report was an article in which he “emphasized the safety of the vaccine under ordinary circumstances” and avoided confronting the ethical questions raised by the experimental procedure

Strong would go on to have a successful career, earning a place at Harvard University as a professor of tropical medicine. This event would remain a hidden dark spot on the record of the acclaimed scientist.

The Bilibid episode remains, however, as a cautionary tale for those engaged in clinical research.

Post a comment or leave a trackback: Trackback URL.


  • Dennis Albert  On 12/28/2020 at 6:07 pm

    Is the COVID vaccine being used on inmates or what?

  • P Guarco  On 07/30/2021 at 5:56 pm

    As a Filipino American I thank you for this very informative article. I am afraid episodes like this are one reason why some populations are Covid vaccine reluctant. I do have one question….I believe Bilibid was used to house Filipino freedom fighters (insurrectos) as well as common criminals. So the trials these trials may have been inflicted on legitimate combatants. Very sad.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: