Attempts to Stem Anthrax Fears Stumble
As public health officials and politicians attempted to stem the public’s anxiety about bioterrorism—in particular, anthrax sent through the mail—unexpected infections and deaths in postal workers exposed to contaminated mail derailed their “don’t worry” message. Only after anthrax contamination showed up at multiple postal sites, as well as in many areas of the Senate and House office buildings, did health officials admit that the form of anthrax that contaminated the letter sent to the office of Senate Majority Leader Sen Tom Daschle (D-SD) was highly processed to a fine powder that could seep out of the seams of envelopes and perhaps even the pores of the paper itself.
Postal workers, who had been assured that they did not need prophylactic treatment, were predictably angry when it was discovered that at least two of their own had died of inhalational anthrax. More suspected deaths and illnesses turned up as health officials began to screen those who had been in the nonpublic areas of post offices for anthrax exposure. Adding to the puzzle is the case of a New York hospital worker who died of inhalational anthrax on October 31, 2001.
In the October 26, 2001, issue of the Morbidity and Mortality Weekly Report (2001;50:909–919), the federal Centers for Disease Control and Prevention (CDC) noted, “This is the first bioterrorism-related anthrax attack in the United States, and the public health ramifications of this attack continue to evolve.”
The agency updated the progress of its investigations in New Jersey, New York, Florida, and Washington, DC, noting that the mail contamination had resulted in 15 infections and 3 deaths by publication time. By the end of the week, it was estimated that as many as 10 000 people in all 4 hot spots were taking antibiotics as prophylaxis against possible exposure to the bacteria.
In an editorial note attached to the October 26, 2001 report, CDC officials noted: “Limited clinical experience is available and no controlled trials in humans have been performed to validate current treatment recommendations for inhalational anthrax. Based on studies in nonhuman primates and other animal and in vitro data, ciprofloxacin or doxycycline should be used for initial intravenous therapy until antimicrobial susceptibility results are known . . . Because of the mortality associated with inhalational anthrax, two or more antimicrobial agents predicted to be effective are recommended; however, controlled studies to support a multiple drug approach are not available. Other agents with in vitro activity suggested for use in conjunction with ciprofloxacin or doxycycline include rifampin, vancomycin, imipenem, chloramphenicol, penicillin and ampicillin, clindamycin, and clarithromycin; but other than for penicillin, limited or no data exist regarding the use of these agents in the treatment of inhalational B anthracis infection. Cephalosporins and trimethoprim-sulfamethoxazole should not be used for therapy. . . . Penicillin is labeled for use to treat inhalational anthrax. However, preliminary data indicate the presence of constitutive and inducible β-lactamases in the B anthracis isolates from Florida, NYC, and DC. Thus, treatment of systemic B anthracis infection using penicillin alone (ie, penicillin G and ampicillin) is not recommended. . . . Toxin-mediated morbidity is a major complication of systemic anthrax. Corticosteroids have been suggested as adjunct therapy for inhalational anthrax associated with extensive edema, respiratory compromise, and meningitis.”
According to the CDC report, ciprofloxacin and doxycycline are first-line therapy for cutaneous anthrax, the most common infection associated with the current terrorist outbreak. The agency noted that intravenous therapy with a multidrug regimen is recommended for cutaneous anthrax with signs of systemic involvement, for extensive edema, or for lesions on the head and neck. Even though the antibiotics may render lesions “culture negative in 24 hours,” progression to eschar formation still occurs. Corticosteroids are sometimes recommended for extensive edema or swelling in the head and neck regions with this skin form of the disease. Although cutaneous anthrax typically is treated for 7 to 10 days, because the risk of simultaneous aerosol exposure seems to be high with this bioterrorist attack, those with the cutaneous form of the disease should be treated for 60 days to treat any latent infection.
The agency advised that prophylaxis for anthrax exposure requires the use of either ciprofloxacin or doxycycline as first-line agents. When these are contraindicated, high-dose penicillin may be an option. The CDC warned that “clinicians prescribing these medications should be aware of their side effects and consult an infectious disease specialist as needed.”
An editorial note in the report reminded readers that the initial anthrax cases occurred among those who had had known or suspected contact with opened letters contaminated with anthrax spores. Later investigations found cases among postal workers who had no known contact with the opened missives. “This suggests that sealed envelopes contaminated with B anthracis passing through the postal system may be the source of exposures,” the editors wrote. “The number of contaminated envelopes passing through the postal system is not known. In addition, automated sorting could damage envelopes and release spores into postal environments; other circumstances that could contribute to the contamination of postal facility environments may be identified.”
In discussing how to deal with people who are possibly exposed to the anthrax spores, the CDC noted that “persons with an exposure or contact with an item or environment known or suspected to be contaminated with B anthracis—regardless of laboratory test results—should be offered antimicrobial prophylaxis. Exposure or contact, not laboratory test results, is the basis for initiating such treatment. Culture of nasal swabs is used to detect anthrax spores. Nasal swabs can occasionally document exposure, but cannot rule out exposure to B anthracis.”
High-Normal Blood Pressure and Cardiovascular Disease
High-normal blood pressure is associated with an increased risk of cardiovascular disease, according to researchers from the Framingham Heart Study, Boston University School of Medicine, Massachusetts General Hospital, Harvard Medical School, Beth Israel Deaconess Medical Center, and the National Heart, Lung and Blood Institute in a report in the November 1, 2001, issue of the New England Journal of Medicine (2001;345:1291–1297).
In their investigation, the researchers, led by Ramachandran S. Vasan, MD, of the Framingham Study, looked for the association between blood-pressure category at baseline and the incidence of cardiovascular disease during a follow-up period among 6859 participants in the Framingham Heart Study. The subjects were initially free of high blood pressure and heart disease.
Blood pressures in the study were classified as optimal with systolic pressures of <120 mm Hg and diastolic pressures of <80 mm Hg; normal with systolic pressures of 120 to 129 mm Hg and diastolic pressures of 80 to 84 mm Hg; and high normal with systolic pressures of 130 to 139 mm Hg and diastolic pressures of 85 to 89 mm Hg. Pressures above those were considered to be high blood pressure.
All the study participants were followed for 12 years, and end points were a major cardiovascular event such as death due to cardiovascular disease, recognized myocardial infarction, stroke, and congestive heart failure. One fourth of the study subjects had high-normal blood pressure at baseline, one third had normal blood pressure, and the rest had optimal blood pressure. Those with high-normal pressure were, on average, older with a high body-mass index and higher serum cholesterol levels than those of the subjects with optimal blood pressure.
During the follow-up, 397 of the study subjects had a first cardiovascular event, including 72 deaths from heart disease. “Cardiovascular-event rates increased in a stepwise manner across the three blood-pressure categories,” the authors wrote. Compared with optimal blood pressure, “high normal blood pressure was associated with a risk factor–adjusted hazard ratio for cardiovascular disease of 2.5 among women and 1.6. . .among men. By contrast, the risk factor–adjusted hazard ratio was 1.5 among women and 1.3 among men.”
In an accompanying editorial, Julio A. Panza, MD, of Washington Hospital Center in Washington, DC, concluded: “Frank hypertension is a prevalent, often unrecognized, and poorly controlled medical condition. If we are to increase the number of patients whose condition is appropriately diagnosed and treated, there is more work to be done. The finding of Vasan et al that high-normal blood pressure is more akin to high blood pressure than it is to normal pressure is an important advance in our understanding of the magnitude of the problem.”