1984 Rajneeshee Bioterror Attack: Motive, Prosecutions, and Legacy

The 1984 Rajneeshee bioterror attack was a deliberate mass poisoning in The Dalles, Oregon, carried out by followers of the Indian guru Bhagwan Shree Rajneesh, who contaminated salad bars at ten local restaurants with Salmonella typhimurium to keep opposing voters home on Election Day. The attack sickened 751 people, hospitalized at least 45, and remains the largest bioterrorist attack in United States history.¹²

What Happened at the Salad Bars

Beginning on September 9, 1984, teams of cult members from the Rajneeshpuram commune fanned out to restaurants in The Dalles, a county seat of about 10,500 people. They poured cultured salmonella onto items on self-service salad bars, into salad dressings, and into coffee creamers. Produce in at least one local supermarket was also contaminated.¹

The outbreak came in two waves. The first ran from September 9 to 18 and peaked on September 15; the second ran from September 19 to October 10 and peaked on September 24. Victims developed severe gastroenteritis, with diarrhea, fever, chills, headache, nausea, vomiting, abdominal pain, and bloody stools that lasted an average of three days. Among the worst cases was a 34-year-old pregnant woman whose newborn was delivered in septic shock. Both survived, and no deaths were recorded.¹²

The bacteria came from a legitimate scientific supplier. Ma Anand Puja, a licensed nurse who ran the Rajneesh Medical Corporation, purchased a standard strain of Salmonella typhimurium from VWR Scientific in Seattle and used commercially available Bactrol discs to grow it in a shed on the commune grounds known as the “Chinese Laundry.”²

The September and October restaurant contaminations were a trial run. A larger attack was planned for on or around Election Day, November 6. Smaller poisoning attempts targeted individual officials: Krishna Deva, the mayor of Rajneeshpuram, helped contaminate doorknobs and urinals at the Wasco County courthouse and poured salmonella into salad dressing at a local restaurant, and another member tried to poison rival politicians by smearing bacteria on her palms and shaking hands at a political event.²

Why the Commune Did It

By mid-1984, leaders at Rajneeshpuram had concluded that the November Wasco County elections would decide the commune’s future. County commissioners controlled land-use decisions critical to the settlement’s expansion, and the roughly outnumbered Rajneeshees were losing a running battle with local Oregonians and the state attorney general, who had sued to disincorporate their city on separation-of-church-and-state grounds.³¹

Ma Anand Sheela, Rajneesh’s personal secretary and the commune’s de facto leader, designed a two-track plan: register thousands of new pro-commune voters by busing homeless people to the ranch, and simultaneously incapacitate anti-Rajneesh voters so they could not reach the polls. The voter-registration track collapsed when the Wasco County clerk halted registrations for probable fraud and the Oregon Secretary of State required prospective voters to appear at special hearings. On Election Day, only 249 Rajneeshpuram residents voted.⁴ The salmonella attack was the other half of the same plan.

Why It Took a Year to Identify as an Attack

Investigators from the Wasco-Sherman Public Health Department, the Oregon Health Division, and the CDC began looking into the outbreak on September 17, 1984. Their case-control and cohort studies found that 80 percent of the affected restaurants had salad bars, compared with only 11 percent of unaffected ones, a relative risk of 7.5. Local health officials ordered all salad bars in The Dalles closed on September 25, and the outbreak ended.¹

Investigators attributed the outbreak to poor restaurant hygiene. They documented minor violations, including improper food rotation and ice-chilled salad bars running at 55 to 60 degrees Fahrenheit rather than the recommended 45. Those conditions could help salmonella grow once introduced but did not, on their own, explain such a widespread, simultaneous outbreak.¹

Several things kept sabotage out of the frame. No one claimed responsibility or made demands. Investigators had no precedent for politically motivated mass food contamination in the United States. The two-wave pattern across multiple unrelated restaurants seemed easier to explain by accident than by design.¹ Oregon Congressman Jim Weaver publicly accused the commune of deliberate contamination, but health authorities and the press dismissed his claim.⁵

How the Plot Unraveled

The truth surfaced only when the Rajneeshee movement collapsed from inside. On September 15, 1985, Sheela and several top lieutenants fled the commune for West Germany. The next day, Rajneesh broke years of public silence to accuse “Sheela and her gang” of wiretapping, attempted murder, and other crimes.⁵

A state-federal task force led by the Oregon Attorney General entered the ranch on October 2, 1985. In the Rajneesh Medical Center laboratory, investigators seized a vial of Salmonella typhimurium. CDC testing confirmed the strain was indistinguishable from the one that had caused the outbreak the previous year.⁵ Testimony from former commune members filled in how the bacteria were cultured, who carried out the contaminations, and how the poisonings fit into the electoral plan.¹

The same investigation surfaced two other schemes tied to the water supply. Cult members had tried pouring salmonella directly into city water tanks and discussed releasing bacteria-laden beavers into the system. Neither worked; The Dalles’ chlorination and purification defeated the quantities the commune could produce.²

Who Was Prosecuted

Ma Anand Sheela

Sheela was arrested in West Germany in October 1985 and extradited to the United States in February 1986. In April 1986, she pleaded guilty to federal charges of immigration fraud, wiretapping, and conspiracy to tamper with consumer products for the salmonella attack. U.S. District Judge Edward Leavy imposed concurrent four-and-a-half-year federal prison terms for the immigration and wiretapping counts, with a five-year suspended sentence for the poisoning conspiracy, and she agreed to pay $469,000 in fines.⁶ On the state side, she pleaded guilty to the attempted murder of Rajneesh’s personal physician, Dr. Swami Devaraj, the poisoning of two Wasco County officials, and arson at the Wasco County Planning Office.⁷

Sheela served 39 months and was released. She moved to Germany and then Switzerland in 1989, having obtained Swiss nationality through a 1984 marriage. She later opened two nonprofit residential homes for elderly and disabled patients near Basel that received government accreditation in 2008.⁸ In 1999, a Swiss court convicted her of “criminal acts preparatory to the commission of murder” in connection with the plot to assassinate the U.S. Attorney for Oregon.⁹

Ma Anand Puja

Diane Yvonne Onang, known as Ma Anand Puja, ran the laboratory and personally directed the restaurant contaminations. She was sentenced to four and a half years in federal prison for conspiracy to tamper with consumer products and three years of probation for wiretapping.⁶

Krishna Deva

David Berry Knapp, the former mayor of Rajneeshpuram, cooperated with investigators after leaving the commune in September 1985 and filed a 22-page affidavit detailing its leadership and criminal activities.¹⁰ U.S. Attorney Charles Turner called his information “essential” and recommended probation. Judge Leavy sentenced him to two years in prison for conspiracy and immigration fraud.¹¹

Bhagwan Shree Rajneesh

On October 28, 1985, Rajneesh and twelve followers were arrested at Charlotte-Douglas International Airport in North Carolina after chartering two Learjets from Rajneeshpuram, ostensibly for Bermuda. The FAA had tracked the aircraft through refueling stops in Salt Lake City and Pueblo, Colorado.¹² A federal grand jury in Portland had returned a secret 35-count indictment the previous week, charging Rajneesh and seven aides with conspiracy and immigration fraud, including arranging hundreds of sham marriages. On November 15, 1985, he accepted a plea deal: a five-year suspended sentence, a $400,000 fine, and immediate departure from the United States. He flew to India that evening.¹³ He later adopted the name Osho and died in India in 1990.

Rajneesh was not charged in connection with the salmonella attack itself. The federal charges he pleaded to concerned immigration fraud.

The Plot to Assassinate the U.S. Attorney

In May 1985, Sheela launched a separate conspiracy to kill Charles Turner, the U.S. Attorney for Oregon then directing a grand jury investigation into the commune’s wiretapping and immigration fraud. Catherine Jane Stubbs, also known as Ma Shanti Bhadra, volunteered to carry out the shooting, bought weapons, and surveilled Turner’s workplace garage. The plot was never executed. A federal grand jury indicted Stubbs and six others in May 1990, but Stubbs had fled to Germany, which denied a U.S. extradition request in 1991. She lived abroad for 20 years before returning voluntarily in September 2005 to plead guilty to conspiracy to murder and federal firearms violations.⁹

The Wiretapping Case

In December 1985, a federal grand jury indicted 21 Rajneeshees for operating a wiretapping network out of a listening post near the commune’s telephone switching center. Members had intercepted and recorded calls into and out of Rajneeshpuram from January 1984 until Sheela’s departure in September 1985. U.S. Attorney Turner called the operation “without precedent in the District of Oregon.”¹⁴

Why the Case Still Matters

The Dalles attack was the first large-scale bioterrorist attack in the United States, but it went publicly unrecognized as deliberate for more than a year, and the federal government did not formally classify it as a biological weapons attack until 1997.¹⁵ It is now cited alongside the 1995 Aum Shinrikyo sarin gas attack in Tokyo and the 2001 U.S. anthrax mailings as a foundational case in the study of biological terrorism.

The case exposed a low barrier to entry for small-scale biological weapons. The commune obtained a common pathogen from a scientific supplier, cultured it with off-the-shelf laboratory materials, and used it on civilians in an ordinary American town. A 2025 analysis in Cureus argued that policymakers should be “far more concerned that biologists will become terrorists” than that terrorists will acquire advanced scientific training, and pointed to “plausible deniability” as a durable advantage of biological weapons: public health and law enforcement systems default to natural explanations and are slow to consider sabotage, as happened in The Dalles.²

1
CDC. A Large Community Outbreak of Salmonellosis Caused by Intentional Contamination of Restaurant Salad Bars
2
National Center for Biotechnology Information. The 1984 Rajneeshee Bioterrorism Attack
3
University of Oregon. The Rajneeshees Oregon Communal Experiment
4
New Republic. The Bhagwan’s Biggest Gamble
5
Food Safety News. For the First 12 Months the Investigation Was All About Salad Bars
6
Los Angeles Times. Former Aides to Guru Plead Guilty
7
New York Times. Former Aides to Guru in Oregon Plead Guilty to Numerous Crimes
8
Swissinfo. The Rebirth of Ma Anand Sheela
9
U.S. Department of Justice. Former Rajneeshee Cult Member Pleads Guilty to Conspiracy to Murder
10
The Oregonian. A Failed Vision Chronology
11
New York Times. Ex-Leader of Commune Gets 2-Year Sentence
12
Los Angeles Times. Indian Guru Seized Trying to Flee US
13
New York Times. Guru to Leave US in Immigration Plea Bargain
14
Los Angeles Times. 21 Rajneesh Followers Indicted in Wiretapping Scheme
15
Defense Technical Information Center. Bioterrorism and Policy