All weekend long Ernesto Blanco felt lousy. The 73-year-old mail clerk could barely keep his eyes open. He had a heavy cough and was struggling for each breath. On Oct. 1, he walked into Cedars Sinai Hospital in Miami to see a doctor.
"He thought there was something strange going on," Mari Orth, his stepdaughter, would later say.
Blanco was right, but it would take two weeks to learn why. Doctors initially said he had pneumonia, and it wasn't until Monday that they made a startling announcement: Blanco had inhalation anthrax.
The case, infectious disease experts say, underscores that diseases don't always behave the way they do in textbooks - and that much remains to be learned about one of mankind's most ancient killers, a disease that only a handful of U.S. doctors have ever seen.
Despite finding anthrax spores in Blanco's nose a week after he walked into the hospital and knowing that anthrax had killed a colleague at the Boca Raton tabloid publisher where Blanco worked, Miami doctors continued to believe their patient had pneumonia. According to family members, Blanco was gravely ill and on a ventilator but is now improving.
His case, experts say, may offer an encouraging lesson: that even people exhibiting advanced symptoms of the disease are not always destined to die.
Bacillus anthrecis, the bacterium that causes anthrax, is at once both mysterious and intimately familiar to scientists. The bug is one of the first bacteria to be formally studied and holds a vaunted place in the annals of microbiology: It was the bacteria that German bacteriologist Robert Koch used in the 1870s to propose the then-radical theory that germs cause disease.
Today, scientists have decoded much of the bacterium's genetic machinery and know minute details about how it lives and how it kills, thanks in part to experiments conducted since the 1950s in rhesus monkeys and other animals.
Because human cases of inhalational anthrax are rare - only 18 in the United States in the 20th century - doctors have had few opportunities to study the disease. (Doctors have had more experience with cutaneous anthrax, the more common skin form of the disease.)
The most significant source of knowledge about inhalational anthrax comes from Ekaterinburg, Russia (formerly the Soviet city of Sverdlovsk), where an outbreak of anthrax in 1979 killed 64 people. The anthrax was later traced to the accidental release of spores from a biological weapons laboratory.
From the Russian cases, doctors developed a clearer picture of inhalation anthrax. Robert Stevens, the photo editor at The Sun tabloid who died of anthrax on Oct. 5, was a textbook case.
Stevens was already gravely ill when he entered the hospital on Oct. 2. He had a fever of 102 degrees and was confused and vomiting. Within hours, doctors placed him on a ventilator.
Dr. Larry Bush, an infectious disease specialist, said he suspected that Stevens had anthrax when he placed the patient's spinal fluid under a microscope and saw rod-shaped bacteria. A chest X-ray revealed a widening of the mediastinum, a cavity outside the lungs where lymph nodes become enlarged. This, too, was typical.
In contrast, Blanco's doctors at Cedars Sinai all but ruled out anthrax when they pieced together his symptoms and lab tests. Though tests showed that he had breathed spores into his nose, cultures showed no evidence that bacteria had entered his lungs or bloodstream.
Also, doctors did not see a widened mediastinum on his chest X-ray.
Doctors put Blanco on antibiotics soon after he entered the hospital, said Dr. David Fleming, deputy director of the federal Centers for Disease Control and Prevention in Atlanta. Perhaps, infectious disease experts have speculated, the drugs wiped out most of the anthrax bacteria in Blanco's blood - making detection difficult.
Doctors were able to find the bacteria only after using a sophisticated test that looks for anthrax DNA in the blood. Though it is unclear when the diagnosis was made, the announcement wasn't made until Monday - two weeks after Blanco was admitted.
Though doctors didn't know that Blanco had anthrax when they started him on antibiotics, the drugs appear to have reversed the infection and saved his life.
Dr. James M. Hughes, a top CDC official, said the case offers an encouraging sign that victims of inhalation anthrax can be successfully treated even if antibiotics are given after symptoms begin.
Previous studies indicated that antibiotics often cure the inhalational form if started before symptoms emerge. About 90 percent of the patients who are treated later than that die of the disease.
"He's lucky he pulled through," said Dr. Michael Donnenberg, chief of infectious diseases at the University of Maryland Medical Center. "But he would not be the first person to survive inhalation anthrax."
The Blanco case was not the first time that doctors have been confused by anthrax. Medical personnel who arrived on the scene of the 1979 anthrax outbreak in Russia initially diagnosed many victims with pneumonia, according to an examination of the case in the March 1993 issue of Proceedings of the National Academy of Sciences.
In medicine, it is not unusual for patients to exhibit symptoms outside the realm of common experience, doctors say. And that could be doubly so for anthrax, a disease more common in animals and Third World nations than in the United States.
"Ninety-nine point nine percent of the medical community has never seen a case of anthrax," said microbiologist David Sullivan of the Johns Hopkins Bloomberg School of Public Health. "It's one of those diseases you just don't think about."
Wire services contributed to this article.