"I'm not like Michael Jackson, but I'm really conscious about washing it," she said.
The latest figures from the World Health Organization show 1,025 lab-confirmed cases of swine flu and 26 deaths in 20 countries. Though many health experts say the virus is at the moment mild, that could change.
"Why this is such a big story is because it's a new strain and a new strain is potentially dangerous," Szymanski said. "But with OCD, it's really about whether your OCD happens to grab on to it or not.
"In talking to patients, I've had some say, 'I'll take swine flu any day, as long as you promise me I'm not going to get AIDS,'" he said. "During the anthrax scare, we were flooded with calls. But I never heard a thing for the avian or West Nile viruses."
Szymanski notes that sufferers seem to be more preoccupied with sexually transmitted disease, perhaps in part because of the nature of OCD -- sufferers imagine losing control, have intrusive sexual thoughts or urges, or excessive religious or moral doubt.
"Typically, when you think about herpes and HIV, there is a kind of personal responsibility that goes along with it," he said. "It's tied up with sexual issues and taboos: 'I wasn't careful enough and I'm a bad person. But when I get the swine flu, I get it like anyone else.'"
At the same time, as publicity ramps up, experts like Szymanski don't want to give sufferers any more "triggers" that might create a new obsession.
Some mental health Web sites like PsycheCentral.com have listed warnings for OCD patients on how to react to the swine flu, urging them not to ignore Centers for Disease Control and Prevention (CDC) warnings.
"For people who have any type of significant anxiety ... times like these are especially difficult," write their psychologists. "You should probably consult with a mental health professional if you are not currently in treatment and feel your distress is climbing.
"If you're already a worrier," they add, "You're likely to need some extra help."
Some online message boards have also been buzzing with those who say they suffer from OCD.
"Is there anyone out there that read the words, 'swine flu' in my title and had sudden onset anxiety?" wrote one person on BeliefNet.com "That was me 16 years ago, except then it was ebola.
"My OCD kept me in a closed loop of thought: It's the end of the world. In my mind, it was going to happen for real," the posting continued. "I went non-functional for days. When I wasn't full 'fight or flight' brain chemical flush, then I was deeply depressed. The cycle last for weeks."
But others, like Mary Ellen, are less panicked.
"I watch everyone freaking out and just kinda laugh," wrote another.
Studies find that it takes an average of 17 years from the time OCD begins for people to obtain appropriate treatment. The disorder tends to be under diagnosed as many sufferers are secretive or ignorant about their symptoms.
Treatment has been improved markedly with the advent of selective serotonin reuptake drugs, according to Dr. Robert Edger, a psychiatrist at Northwest Memorial Hospital and Children's Memorial Hospital in Chicago.
Those drugs are even more effective when they go hand in hand with psychotherapy.