U.S. President Barack Obama urged everyone Saturday not to give in to “hysteria or fear” about the deadly Ebola virus, but hysteria and fear are helping spread conspiracy theories like, well, a virus. Some of the most outrageous claims are coming from Liberia’s Daily Observer, but there are also U.S.-based wing-nuts exploiting the current hysteria and fear to put forward their own creative charges about an infectious disease that’s killed thousands of people in Liberia, Sierra Leone and Guinea since December, and very few anywhere else.

“Conspiracies against the powerless tend to be effective because the masses often feel that way,” James F. Broderick, an English professor at New Jersey City University and co-author of “Web of Conspiracy: A Guide to Conspiracy Theory Sites on the Internet,” told The New York Times. “They reflect and reinforce the idea that ordinary citizens are victims of the government.”

The claims are following a pattern similar to conspiracy theories that surfaced for the 2009 H1N1 influenza outbreak that by some estimates killed a half-million people worldwide.

“Besides the usual anti-vaccine paranoia that demonized the [H1N1] vaccine as, alternately, ineffective, full of ‘toxins,’ a mass depopulation plot, and many other equally ridiculous fever dream nonsense, there was the quackery,” David Gorski, a surgical oncologist who writes under the pseudonym Orac at ScienceBlogs, said in a column published Thursday. “Truly, pandemics bring out the crazy.”

The current Ebola outbreak ravaging three West African countries has yet to reach the level of pandemic, but since September the conspiracy-theory meter has been running high.

Here are the two most common Ebola conspiracy theories, all of which have antecedents in previous infectious disease outbreaks and efforts to contain them:

Like HIV, Ebola was created by the U.S. as a biological weapon.  

We’ve seen similar charges about diseases or their vaccines before, notably surrounding HIV in Africa and polio vaccinations in Pakistan. The narrative for this popular conspiracy meme goes like this: The U.S. government has a secret bioweapons program that uses Africa as a staging ground for testing the effectiveness of bioengineered viruses and their cures for use in future warfare. This appears to be one of the main conspiracies promoted by the Daily Observer, Liberia's main English-language newspaper.

“It should not be so shocking to realize the military purpose of Ebola as yet another highly destructive weapon in its vast lethal arsenal could be potentially used to eliminate an enormous segment of this planet’s readily expendable current human population,” writes Joachim Hagopian in an article published earlier this month at the GlobalResearch website.

“Anyone that had the cure for this bug would be in the position to select who gets saved and who does not. That is the whole point of biowarfare,” Tom Chatham wrote recently at the Project Chesapeake website.

Ebola is a way for pharmaceutical companies to make tons of money.

The way pharmaceuticals are created, patented and marketed has offered a convincing platform on which to build the idea that drugmakers profit from the spread of infectious diseases that require their treatments. It’s a familiar narrative with truthful undertones. After all, pharmaceutical companies routinely sell pricey life-saving treatments and fight hard to retain the rights to their patents for as long as possible before generic versions of their drugs can be produced at lower costs to patients.

“Who has the most to gain by a worldwide outbreak of Ebola? Whoever can sell a solution to the problem, right? And just who might that be? Global pharmaceutical companies to the rescue!” reads a recent article on the blog site Western Journalism, which proposes the idea the U.S. government will eventually hand-pick a pharmaceutical company to fast track an Ebola vaccine once the virus becomes a global pandemic.

Much like the vaccine conspiracy theories related to childhood vaccines, the “Big Pharma” routine crosses ideological boundaries. Right-wingers see big government conspiring to create an effective way to kill millions (or cure them) while holistic medicine proponents on the left see government and corporations suppressing the benefits of a natural Ebola cure.

Infowars.com, a popular website for these type of stories, is also perpetuating the theory the government and pharmaceutical companies are conspiring to find a way to maximize profitability, namely by suppressing a less costly cure to promote their more profitable genetically modified cure.  

Because Obama.

One virus conspiracy theory we haven’t seen before has emerged from conservative activists Phyllis Schlafly (who blames Central American child migrants for spreading disease in the U.S.) and Larry Klayman (who believes Obama is an African-born Muslim). They claim the president wants Ebola to spread in the United States to further his anti-America agenda and his war against white people. While Schlafly and Klayman reside at the fringes of the American far-right, conservative radio host Rush Limbaugh has a much larger following. Earlier this month the radio talk show host said Obama wants Americans to contract the Ebola virus as payback for slavery.