-
[show abstract]
[hide abstract]
ABSTRACT: An outbreak of tick-borne relapsing fever (TBRF) originating at the North Rim of Grand Canyon National Park was investigated in 1990. To determine risk factors for the disease, almost 7,000 parties of visitors were surveyed; over half responded, representing > 10,000 people. Fifteen cases of confirmed or probable TBRF were identified in visitors and 2 in employees. All patients except one experienced symptoms after overnight stays in a group of cabins that had not been rodent-proofed after a TBRF outbreak in 1973 (relative risk for visitors [RR] 8.2, 95% confidence interval [CI] 1.1-62). Seven cases of TBRF were associated with a single cabin (RR 98, 95% CI 30-219). Structural flaws and rodent nests were common in the implicated cabins and rare in unaffected cabins. This investigation suggests that measures to rodent-proof cabins at sites where TBRF is endemic prevent reinfestation of cabins by infected rodents and tick vectors, thereby preventing the spread of disease in humans.
The American journal of tropical medicine and hygiene 01/2002; 66(1):71-5. · 2.59 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Epidemiological methods are needed to evaluate community exposure to Borrelia burgdorferi, the causative agent of Lyme disease (LD). For LD serodiagnosis, the Centers for Disease Control and Prevention (CDC) recommends a 2-test approach that involves enzyme immunoassay (EIA) testing and Western immunoblotting (WB) of EIA-equivocal and EIA-positive specimens. The specificity of this approach was evaluated among residents of a LD-endemic community and was compared with WB alone and with a simplified 2-test approach (WB of equivocal EIA only). Participants reporting no previous diagnosis of LD were recruited during a community-wide serosurvey on Block Island, Rhode Island. Of 80 eligible participants, 20 had received LD vaccine. Seven (35%) of 20 vaccinees and 22 (37%) of 60 nonvaccinees reported nonspecific symptoms compatible with LD in the previous year. In this highly LD-endemic community, the overall specificity of the CDC-recommended approach was highest (100%), followed by WB alone (98.7%), then the simplified approach (95%).
The American journal of tropical medicine and hygiene 12/2001; 65(5):563-6. · 2.59 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In the summer of 2000, an outbreak of primary pneumonic tularemia occurred on Martha's Vineyard, Massachusetts. The only previously reported outbreak of pneumonic tularemia in the United States also occurred on the island in 1978.
We conducted a case-control study of adults with pneumonic tularemia and investigated the environment to identify risk factors for primary pneumonic tularemia. Patients with confirmed cases were residents of or visitors to Martha's Vineyard who had symptoms suggestive of primary pneumonic tularemia, were ill between May 15 and October 31, 2000, and had a positive laboratory test for tularemia. Controls were adults who had spent at least 15 days on Martha's Vineyard between May 15 and September 28, 2000.
We identified 15 patients with tularemia; 11 of these cases were primary pneumonic tularemia. Francisella tularensis type A was isolated from blood and lung tissue of the one man who died. Patients were more likely than controls to have used a lawn mower or brush cutter in the two weeks before the illness or before an interview, for controls (odds ratio, 9.2; 95 percent confidence interval, 1.6 to 68.0) and during the summer (odds ratio, undefined; 95 percent confidence interval, 1.8 to infinity). Lawn mowing and brush cutting remained significant risk factors after adjustment for other potentially confounding variables. Only one patient reported being exposed to a rabbit while cutting brush. Of 40 trapped animals, 1 striped skunk (Mephitis mephitis) and 1 Norway rat (Rattus norvegicus) were seropositive for antibodies against F. tularensis.
Study of this outbreak of primary pneumonic tularemia implicates lawn mowing and brush cutting as risk factors for this infection.
New England Journal of Medicine 12/2001; 345(22):1601-6. · 53.30 Impact Factor
-
D T Dennis,
T V Inglesby,
D A Henderson,
J G Bartlett,
M S Ascher,
E Eitzen,
A D Fine,
A M Friedlander,
J Hauer,
M Layton,
S R Lillibridge,
J E McDade,
M T Osterholm,
T O'Toole,
G Parker,
T M Perl,
P K Russell,
K Tonat
[show abstract]
[hide abstract]
ABSTRACT: The Working Group on Civilian Biodefense has developed consensus-based recommendations for measures to be taken by medical and public health professionals if tularemia is used as a biological weapon against a civilian population.
The working group included 25 representatives from academic medical centers, civilian and military governmental agencies, and other public health and emergency management institutions and agencies.
MEDLINE databases were searched from January 1966 to October 2000, using the Medical Subject Headings Francisella tularensis, Pasteurella tularensis, biological weapon, biological terrorism, bioterrorism, biological warfare, and biowarfare. Review of these references led to identification of relevant materials published prior to 1966. In addition, participants identified other references and sources.
Three formal drafts of the statement that synthesized information obtained in the formal evidence-gathering process were reviewed by members of the working group. Consensus was achieved on the final draft.
A weapon using airborne tularemia would likely result 3 to 5 days later in an outbreak of acute, undifferentiated febrile illness with incipient pneumonia, pleuritis, and hilar lymphadenopathy. Specific epidemiological, clinical, and microbiological findings should lead to early suspicion of intentional tularemia in an alert health system; laboratory confirmation of agent could be delayed. Without treatment, the clinical course could progress to respiratory failure, shock, and death. Prompt treatment with streptomycin, gentamicin, doxycycline, or ciprofloxacin is recommended. Prophylactic use of doxycycline or ciprofloxacin may be useful in the early postexposure period.
JAMA The Journal of the American Medical Association 07/2001; 285(21):2763-73. · 30.03 Impact Factor
-
JAMA The Journal of the American Medical Association 09/2000; 284(6):695-6. · 30.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Exposure to cats infected with Yersinia pestis is a recently recognized risk for human plague in the US. Twenty-three cases of cat-associated human plague (5 of which were fatal) occurred in 8 western states from 1977 through 1998, which represent 7.7% of the total 297 cases reported in that period. Bites, scratches, or other contact with infectious materials while handling infected cats resulted in 17 cases of bubonic plague, 1 case of primary septicemic plague, and 5 cases of primary pneumonic plague. The 5 fatal cases were associated with misdiagnosis or delays in seeking treatment, which resulted in overwhelming infection and various manifestations of the systemic inflammatory response syndrome. Unlike infections acquired by flea bites, the occurrence of cat-associated human plague did not increase significantly during summer months. Plague epizootics in rodents also were observed less frequently at exposure sites for cases of cat-associated human plague than at exposure sites for other cases. The risk of cat-associated human plague is likely to increase as residential development continues in areas where plague foci exist in the western US. Enhanced awareness is needed for prompt diagnosis and treatment.
Clinical Infectious Diseases 07/2000; 30(6):893-900. · 9.15 Impact Factor
-
T V Inglesby, D T Dennis,
D A Henderson,
J G Bartlett,
M S Ascher,
E Eitzen,
A D Fine,
A M Friedlander,
J Hauer,
J F Koerner,
M Layton,
J McDade,
M T Osterholm,
T O'Toole,
G Parker,
T M Perl,
P K Russell,
M Schoch-Spana,
K Tonat
[show abstract]
[hide abstract]
ABSTRACT: The Working Group on Civilian Biodefense has developed consensus-based recommendations for measures to be taken by medical and public health professionals following the use of plague as a biological weapon against a civilian population.
The working group included 25 representatives from major academic medical centers and research, government, military, public health, and emergency management institutions and agencies.
MEDLINE databases were searched from January 1966 to June 1998 for the Medical Subject Headings plague, Yersinia pestis, biological weapon, biological terrorism, biological warfare, and biowarfare. Review of the bibliographies of the references identified by this search led to subsequent identification of relevant references published prior to 1966. In addition, participants identified other unpublished references and sources. Additional MEDLINE searches were conducted through January 2000.
The first draft of the consensus statement was a synthesis of information obtained in the formal evidence-gathering process. The working group was convened to review drafts of the document in October 1998 and May 1999. The final statement incorporates all relevant evidence obtained by the literature search in conjunction with final consensus recommendations supported by all working group members.
An aerosolized plague weapon could cause fever, cough, chest pain, and hemoptysis with signs consistent with severe pneumonia 1 to 6 days after exposure. Rapid evolution of disease would occur in the 2 to 4 days after symptom onset and would lead to septic shock with high mortality without early treatment. Early treatment and prophylaxis with streptomycin or gentamicin or the tetracycline or fluoroquinolone classes of antimicrobials would be advised.
JAMA The Journal of the American Medical Association 06/2000; 283(17):2281-90. · 30.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Lyme disease is caused by infection with the spirochete Borrelia burgdorferi and is the most commonly reported vector-borne disease in the United States. Borrelia burgdorferi is transmitted to humans by infected Ixodes scapularis and I. pacificus ticks. Lyme disease is typically evidenced in its early stage by a characteristic rash (erythema migrans), accompanied by nonspecific symptoms (e.g., fever, malaise, fatigue, headache, myalgia, and arthralgia). Lyme disease can usually be treated successfully with standard antibiotic regimens.
1992-1998.
Lyme disease surveillance data are reported to CDC through the National Electronic Telecommunication System for Surveillance, a computerized public health database for nationally notifiable diseases. During 1992-1998, data regarding reported cases of Lyme disease included county and state of residence, age, sex, and date of onset. Descriptive analyses were performed, and cumulative incidence by state, county, age group, and sex were calculated.
During 1992-1998, a total of 88,967 cases of Lyme disease was reported to CDC by 49 states and the District of Columbia, with the number of cases increasing from 9,896 in 1992 to 16,802 in 1998. A total of 92% of cases was reported from eight northeastern and mid-Atlantic states and two north-central states. Children aged 5-9 years and adults aged 45-54 years had the highest mean annual incidence.
Lyme disease is a highly focal disease, with the majority of reported cases occurring in the northeastern and north-central United States. The number of reported cases of Lyme disease increased during 1992-1998. Geographic and seasonal patterns of disease correlate with the distribution and feeding habits of the vector ticks, I. scapularis and I. pacificus.
The results presented in this report will help clinicians evaluate the prior probability of Lyme disease and provide the framework for targeting human Lyme disease vaccine use and other prevention and treatment interventions.
MMWR. CDC surveillance summaries: Morbidity and mortality weekly report. CDC surveillance summaries / Centers for Disease Control 05/2000; 49(3):1-11.
-
Journal of American Medical Association (JAMA). 01/2000; 283:2281-2290.
-
[show abstract]
[hide abstract]
ABSTRACT: The Centers for Disease Control and Prevention (CDC) recommend a two-test approach for the serodiagnosis of Lyme disease (LD), with EIA testing followed by Western immunoblotting (WB) of EIA-equivocal and -positive specimens. This approach was compared with a simplified two-test approach (WB of EIA equivocals only) and WB alone for early LD. Case-patients with erythema migrans (EM) rash >/=5 cm were recruited from three primary-care practices in LD-endemic areas to provide acute- (S1) and convalescent-phase serum specimens (S2). The simplified approach had the highest sensitivity when either S1 or S2 samples were tested, nearly doubling when S2 were tested, while decreasing slightly for the other two approaches. Accordingly, the simplified approach had the lowest negative likelihood ratio for either S1 or S2. For early LD with EM, the simplified approach performed well and was less costly than the other testing approaches since less WB is required.
The Journal of Infectious Diseases 04/1999; 179(4):931-8. · 6.41 Impact Factor
-
New England Journal of Medicine 12/1998; 339(22):1637; author reply 1638-9. · 53.30 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Lyme disease, caused by infection with Borrelia burgdorferi, is the most frequently reported arthropod-borne disease in the United States. To develop a national map of the distribution of the vectors of B. burgdorferi to humans (Ixodes scapularis Say and Ixodes pacificus Cooley & Kohls ticks), we sent questionnaires to acarologists, health officials, and Lyme disease researchers; surveyed the 1966-1996 MEDLINE data base; and reviewed 1907-1995 National Tick Collection data. Tick collection methods cited included flagging and dragging, deer surveys, small- and medium-sized mammal surveys, CO2 baiting, and receipt of tick submissions. A total of 1,058 unique, county-specific I. scapularis and I. pacificus records was obtained. Tick populations were classified as "reported" (< 6 ticks and 1 life stage identified) or "established" (> or = 6 ticks or > 1 life stage identified). Established populations of I. scapularis were identified in 396 counties in 32 states in the eastern and central United States, whereas established populations of I. pacificus were found in 90 counties in 5 western states. Counties with established populations were most concentrated in the northeastern, upper northcentral, and west-coastal states but were also clustered in southeastern and Gulf-coastal states. A less concentrated distribution was found in the south-central states. Reports were notably missing from all but a few counties in Ohio, West Virginia, western Virginia and North Carolina, Kentucky, and Tennessee. They were absent in the Great Plains and Rocky Mountain regions and from large areas of western states east of the Cascade and Sierra Nevada cordilleras. These data are useful for identifying areas of Lyme disease risk, for targeting Lyme disease prevention strategies, and for monitoring trends in spatial distribution of Lyme disease vector ticks.
Journal of Medical Entomology 09/1998; 35(5):629-38. · 1.76 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Reported cases of Lyme disease in Hunterdon County, New Jersey, increased almost 200% from 75 (67/100,000 population) in 1992 to 216 (193/100,000 population) in 1993. For evaluation of risk factors for Lyme disease and for determination of the cause of this increase, a case-control study was conducted, and the reporting practices of physicians' offices were evaluated. For cases reported in 1993, age and sex distribution, month of disease onset, and proportion of cases with erythema migrans rash were within expected limits. Analysis of age-matched case-control data showed that rural residence; clearing periresidential brush during spring and summer months; and the presence of rock walls, woods, deer, or a bird feeder on residential property were associated with incident Lyme disease. A review of physician reporting patterns suggested that the increase in reported cases in 1993 was due to improved reporting as well as to an increase in the numbers of patients diagnosed with Lyme disease. In addition, substantial underreporting of Lyme disease by physicians' offices was found.
American Journal of Epidemiology 02/1998; 147(4):391-7. · 5.22 Impact Factor
-
The Lancet 11/1997; 350(9086):1191-2. · 38.28 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: An ELISA containing a purified flagellar antigen from Borrelia burgdorferi (FLA-ELISA) was evaluated. The FLA-ELISA, detecting IgM and IgG together, did not have adequate specificity by itself. Good accuracy was obtained, however, when the FLA-ELISA was the first step in a two-step protocol that used immunoblotting as a conditional second test. Samples that scored positive or equivocal by the FLA-ELISA were evaluated with separate IgM and IgG immunoblots. The sensitivity of the two-step process for patients with erythema migrans or with later manifestations of Lyme disease was 64% and 100%, respectively. The specificity for health blood donors was 100% and was 90% for the aggregate of all persons with illness that may cause serologic cross-reactivity (98% if the samples from relapsing fever patients were excluded). Test precision was 96% overall, 99% for Lyme disease case serum samples, 100% for specimens from blood donors, and 88% for samples from persons with other illness.
The Journal of Infectious Diseases 09/1996; 174(2):346-53. · 6.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A retrospective case-control study investigated 45 Missouri outpatients with annular rashes meeting a surveillance case definition for erythema migrans and with onset in 1990-1991. Risk factors included being male, living near a body of water, and hunting. Twenty patients (44%) associated their rash with the bite of a tick; of these, 5 described an adult Amblyomma americanum. A typical rash was described as expanding over time and measuring 8 cm in diameter at 4 days after onset. Mild constitutional symptoms were common but fever was uncommon. Serologic tests failed to incriminate Borrelia burgdorferi or selected other arthropodborne pathogens. Skin specimens from suspected erythema migrans lesions of 23 Missouri patients sampled prospectively in 1991-1993 were culture-negative for B. burgdorferi. Thus, tick bite-associated annular rashes in Missouri remain idiopathic. Possible causes include infection with a novel A. americanum-transmitted pathogen and an atypical toxic or immunologic reaction to tick-associated proteins.
The Journal of Infectious Diseases 09/1995; 172(2):470-80. · 6.41 Impact Factor
-
D T Dennis
[show abstract]
[hide abstract]
ABSTRACT: A clear understanding of the epidemiology of Lyme disease is needed to bring about its effective treatment, prevention, and control. Strategies for effective intervention must be based on quantitative descriptions of the complex interactions of B. burgdorferi with its human and other vertebrate hosts, tick vectors, and the environment. Sound decision making on diagnosis and patient management requires an understanding of the prior probabilities of infection and disease, the performance characteristics of laboratory tests, and the cost-benefits of various treatments. Lyme disease is still a relatively new disease for which there are many unanswered questions; it is an exciting and challenging model of an emerging vector-borne zoonotic disease.
Dermatologic Clinics 08/1995; 13(3):537-51. · 2.16 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Treatment of unsubstantiated Lyme disease has led to serious complications in some cases. Two case-control studies, based on information in clinical records of patients discharged with a diagnosis of Lyme disease during 1990-1992, were conducted at a central New Jersey hospital. Twenty-five patients with biliary disease were identified, and 52 controls were selected from 1352 patients with suspected Lyme disease. Only 3% of 71 evaluatable subjects met the study criteria for disseminated Lyme disease. Patients with biliary disease were more likely than were antibiotic controls to have received ceftriaxone and more likely than ceftriaxone controls to have received a daily ceftriaxone dose > or = 40 mg/kg and to be < or = 18 years old. Fourteen of 25 biliary case-patients underwent cholecystectomy; all had histopathologic evidence of cholecystitis and 12 had gallstones. Thus, treatment of unsubstantiated diagnoses of Lyme disease is associated with biliary complications.
The Journal of Infectious Diseases 03/1995; 171(2):356-61. · 6.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Currently, the best medium for culture of Borrelia burgdorferi, the etiologic agent of Lyme disease, is Barbour-Stoenner-Kelly (BSK), or its modifications. This medium is complex, expensive, and laborious to prepare. A recent report suggested that a less expensive and simpler medium, hypertonic Columbia broth, might be useful as a transport medium for human tissues infected with B burgdorferi. To test this observation, hypertonic Columbia broth, Amies broth, distilled water, physiologic saline, phosphate-buffered saline (PBS), and modified Stuart medium were compared with BSK II as transport media, using ear and tail tissue samples from B burgdorferi-infected laboratory mice and using holding times and temperatures simulating actual transport conditions. The results showed BSK II to be markedly superior to the other media tested, although B burgdorferi remained viable in a few tissue samples held at room temperature in hypertonic Columbia broth, physiologic saline, or PBS for up to 2 days. Barbour-Stoenner-Kelly II continues to be the best medium for transport of tissues infected with B burgdorferi.
American Journal of Clinical Pathology 03/1994; 101(2):154-6. · 2.60 Impact Factor
-
Clinical Infectious Diseases 10/1993; 17(3):523-4. · 9.15 Impact Factor
