News organizations, the targets in all of the anthrax cases confirmed so far, responded to new incidents Friday at NBC News and the New York Times by intensifying their scrutiny of mail and packages, as did package-delivery companies.
Doctors reported that patients were hoarding antibiotics, convinced that their throat tickles and coughs could signal the onslaught of flu-like anthrax symptoms.
"It's bordering on mass hysteria," said Dr. Michael Hirt, an internist and medical director of the Center for Integrative Medicine at Encino-Tarzana Regional Medical Center.
The volume of patients seeking help for real or perceived maladies seemed to increase despite health officials' pleas for calm.
At the Parker Post Office south of Denver, normal operations screeched to a halt shortly before 9 a.m., when a postal worker stamped an envelope so hard that white powder spilled out.
A hazardous materials team descended on the scene, joined by police, firefighters and units of the FBI, EPA, National Guard and the Postal Inspection Service. Four workers were decontaminated then taken to a trauma center, while 48 of their co-workers were whisked away by school bus for questioning.
Even as other Denver mail carriers abandoned their routes to rush to hospital emergency rooms, a portable lab determined the "suspicious white substance" was innocuous. It turned out to be vanilla pudding powder. The torn and much-analyzed envelope was eventually delivered by hand by a postal inspector.
The Connecticut Department of Environmental Protection was evacuated Thursday when employees discovered a substance police later said was apparently nondairy creamer. A department store in suburban Detroit was emptied after a white powdery substance was found leaking from a statue. Emergency workers later determined it was casting clay.
In Oxnard, the Fire Department evacuated its lobby Friday after a man dropped off a package of toilet paper that he said contained a white powdery substance. No one was allowed in or out of the building all afternoon as hazardous material teams conducted tests.
Not all of Friday's scares started with white stuff.
Authorities shut down Alcatraz Island at 2:10 p.m. Friday after a man with a backpack evaded park rangers' questions and attempted to flee, said Rich Weideman, spokesman for the Golden Gate National Recreation Area.
It turned out the large satchel contained only cameras and film. Not wanting to take chances, however, park staff canceled all tours for the rest of the day.
As the media-related anthrax cases expanded from a supermarket tabloid in Florida to NBC News offices in New York, scores of news organizations took precautionary measures to protect themselves.
At some offices, including those of Newsweek, the Los Angeles Times, CBS, ABC and CNN, top executives temporarily suspended all internal mail delivery, as did several movie studios.
In Burbank, a portion of NBC's West Coast offices was sealed off Friday to investigate a suspicious package that arrived earlier this week. Firetrucks and emergency squads were lined up outside the building for hours while officials from the city's hazardous materials unit and the county Health Department conducted tests.
In the Los Angeles Times' newsroom, a small quantity of a powder-like substance was discovered on a desk in its book review section. The Fire Department quarantined the building for about 90 minutes Friday night and investigated. The substance "tested negative," a Fire Department official said, and employees were allowed to leave. The substance wasn't identified.
In Ohio, the Columbus Dispatch's six-story building was closed for about 2½ hours Friday after an employee opened a Halloween card and found a powdery substance inside.
The constant rat-a-tat of new anthrax scares sent thousands of Americans running to their doctors, county health departments, online vendors and even south of the border for help.
Newport Beach plastic surgeon Michael Elam said he was receiving up to 10 calls a day from patients asking for Cipro, an antibiotic used to treat anthrax. He said he was refusing them all, even turning down his wife.
Some doctors, though, were giving patients what they wanted. Lois Steidel, a pharmacy technician at Newport Beach Pharmacy, said her office was filling about three times the normal number of Cipro prescriptions, going from 10 to 30 a day. The prescriptions were larger too: 100 tablets, instead of the usual 20.
Demand for Cipro ignited an explosion of new Web sites retailing the drug at high prices. Ken Brown, who operates Winnepeg-based Healthmeds.com, said his company had hired 10 additional customer service agents and four pharmacists to handle the more than 50 orders per hour for Cipro. At other Web sites, business was just as brisk and prices were exceeding $5.50 a pill in some cases, analysts said.
Sales of Cipro also increased at Tijuana pharmacies in the past week, store workers said. Most of the sales were to U.S. citizens crossing the border to purchase the antibiotic, said Eduardo Vargas, salesperson at Farmacia Castañeda, located just beyond the border fence.
Vargas said the Mexican-manufactured pharmaceutical sells for less than $1 a pill.
Nationwide, government officials held news conferences largely to try to ease public anxieties, yet acknowledging all the while that tension was rising.
San Francisco Mayor Willie Brown tried to assuage fears by alternately assuring residents that the city is prepared for any potential problems and making light of false alarms.
One day recently, the dapper mayor recounted Friday, City Hall was evacuated because a suspicious shoe box had been left unattended. It ended up being a false alarm.
"A Gucci shoe box was found at City Hall," Brown said with a straight face. "No City Hall worker can afford Gucci. If it had been Prada, it would have been different."