Anthrax. Surveillance Protocol. Provider Responsibilities. Laboratory Responsibilities. Infectious Disease Epidemiology Program

Transcription

1 January 2007 may result from a naturally occurring, unintentional exposure such as from infected animals or from an intentional exposure such as from a bioterrorism (BT) event. When necessary this protocol addresses unintentional and intentional exposures separately; otherwise the protocol applies to both situations. This protocol applies when a case of cutaneous, gastrointestinal, or inhalational anthrax is highly suspected, i.e. when the patient is moribund, exhibiting some second stage symptoms including a widened mediastinum or eschar with preliminary laboratory evidence of rod shaped bacillus in blood, CNS, or eschar specimens, or first stage symptoms associated with a confirmed exposure to Bacillus anthracis. This protocol does not apply to cases with non-specific flulike, gastrointestinal, neurologic, or rash-like symptoms without association to a confirmed anthrax exposure. Provider Responsibilities 1) Report confirmed or suspected cases of anthrax to the local health department immediately by phone 24/7/365; do not wait for laboratory confirmation. Anticipate the need to collaborate with public health on: a) Confirmation of the clinical diagnosis. b) Laboratory confirmation of the diagnosis. Laboratory testing should begin at the hospital laboratory. If results are suspicious for anthrax, confirmatory testing must occur through the Office of Laboratory Services ( ). c) Investigation of the source of infection. Health officials will need to investigate urgently to identify the source of infection. This investigation will usually begin with interviews of the patient, family and close friends. 2) Complete the provider (yellow) portion of the WVEDSS form and forward to the local health department. Forward copies of the laboratory reports to the local health department when available. Laboratory Responsibilities 1) Report confirmed or suspect cases of anthrax to the local health department immediately. Consult with the Office of Laboratory Services ( ) urgently regarding any requests for testing or confirmation of anthrax in a clinical or environmental sample. 2) Refer suspect isolates to Office of Laboratory Services for confirmation and further characterization. Page 1

2 Public Health Action 1) Prior to the occurrence of an anthrax case a) Protect employee health: i) Educate employees: (1) is NOT transmitted from a person who has the disease. Standard precautions should be used with persons diagnosed with anthrax. (2) CAN be transmitted by direct contact with or inhalation of spores. Untrained unprotected workers should NOT enter an area known or suspected to be contaminated with anthrax spores or come into direct contact with items or equipment contaminated with spores until the area has been decontaminated. ii) Assemble and train a BT epidemiologic response team: (1) Assemble BT epidemiologic response team: Identify staff for a BT epidemiologic response team that can adequately respond to a large outbreak by conducting surveillance and epidemiologic investigations after a BT event. (2) Periodically train and pre-drill individuals on the team in their respective responsibilities during an outbreak. iii) Educate health care providers and the public in the recognition and diagnosis of anthrax. iv) Educate providers and laboratories to report anthrax infections to the local health department in the patient=s county of residence immediately. 2) If a suspected case of anthrax is reported, the LHD should contact the Infectious Disease Epidemiology Program (IDEP) immediately (do not wait for lab confirmation to contact IDEP). The local health department should anticipate the need to collaborate with IDEP, other state and local jurisdictions and Federal public health officials and law enforcement. 3) Steps in investigation a) Confirm cases: i) For each suspected case, immediately obtain a complete clinical and laboratory history. Review the WVEDSS Investigation Form, complete any missing data, and determine whether a case is clinically or laboratory confirmed (See Case Definition). ii) Assure that appropriate laboratory specimens are obtained on each suspected case (see Laboratory Notes). Specimens of blood or vesicular fluid (for cutaneous anthrax cases) are to be sent to the local hospital laboratory (Sentinel lab) for preliminary confirmation of Bacillus anthracis. If results are suspicious, the specimens will be sent to the WV Office of Laboratory Services (OLS) (Reference lab) for confirmation. Specimens will be packaged and shipped to OLS according to the OLS laboratory protocol. Page 2

3 4) Incident Triage critical: Determine if the case experienced natural exposure to anthrax within 7 days prior to onset of symptoms, including exposure to 1) infected livestock; 2) to wool, hides, leather or other leather products from infected animals, or 3) ingestion of infected animals. Obtain a travel history to determine if the case traveled to an enzootic area during the incubation period. a) If a clear source is identified on the initial interview, begin active surveillance to identify other cases exposed to the same source. b) If no clear source is identified on initial interview, begin active surveillance to identify other cases. 5) Outbreak investigation: Outbreak investigation requires collaboration with experienced epidemiologists, environmentalists and laboratorians. The basic steps are identified here: a) Case Finding: i) Develop a working case definition: Develop a working case definition for the outbreak investigation. After the outbreak has been identified, a working case definition may be considered as follows: 1) a confirmed case of anthrax, 2) a clinically confirmed case of anthrax while laboratory confirmation of exposure to B. anthracis is pending or 3) a suspected case of anthrax who is clinically compatible, not laboratory confirmed, and has a confirmed exposure to B. anthracis. (See Case Definition Section). ii) Begin enhanced passive surveillance: Immediately begin enhanced passive surveillance as needed with health care providers and laboratories in the county. Educate health care providers and the public in the recognition and diagnosis of anthrax. iii) Conduct active surveillance: If necessary, alert the regional epidemiologist and be prepared to expand active surveillance throughout the region, e.g., be prepared to interview providers and patients, and review/abstract patient records. iv) Confirm new cases: Receive and screen reports of suspected cases, and confirm new cases. v) Develop a line list of cases: Develop a line listing of all confirmed and suspect cases. Record information on: (1) Case ID number (use this number to link to other databases), (2) Name, (3) Age, date of birth, (4) Location (hospital, clinic, home), (5) Time of onset of symptoms, (6) Classification of case (pending, ruled out, suspected, clinically confirmed, and laboratory confirmed), (7) Lab confirmation status (confirmed, negative, pending), (8) Status of clinical information (complete or incomplete), and (9) Status of exposure information (complete or incomplete). vi) Use the line listing to make work assignments to complete missing information. Page 3

4 b) Develop and maintain a data base of pertinent clinical and exposure data for hypothesis testing. Plan to collaborate with an experienced epidemiologist on exposure assessment, as follows: i) Interview a representative sample of cases and obtain a complete risk factor and exposure history, including travel and activities during the case=s exposure period (usually one to seven days, but up to 60 days, before onset of symptoms). ii) If a possible source is suspected, continue the interview with the same sample of cases. Obtain more detailed information, including the type, location, and specific areas, duration, relative amount, and method of dissemination of exposure. iii) Perform epidemiological, laboratory and environmental studies to test / refine / confirm hypotheses. 6) Identify exposed population: a) Definition of an exposed individual: An exposed individual will be a person who shared or possibly shared airspace that was contaminated by B. anthracis, had direct contact with contaminated material such as powder or other environmental exposures as part of a BT event, touched an infected animal, or ingested contaminated food or water. b) Develop a line listing of all persons possibly exposed using the Exposed Individual Line Listing Form. Record each person=s exposure risk based upon proximity to exposure. 7) Surveillance of exposed population: a) Contact and referral of exposed: Assure that all exposed individuals are contacted within 24 hours and refer them for post exposure prophylaxis (PEP), as necessary (See Treatment Section). For large populations, alert the public about the location of clinical centers for treatment or PEP through media announcements. b) Surveillance of exposed individuals: Conduct surveillance of all exposed individuals for 60 days. 8) Prevention and Control: a) Environmental exposures: After the source has been identified, remove people from any environment confirmed or suspected to be contaminated with anthrax spores until decontamination is achieved. b) Post exposure prophylaxis: Because of the short incubation period, and the high mortality, PEP must begin before the investigation is complete. See Treatment Section for PEP guidelines. Recommend to the State Health Commissioner that PEP should be offered to: i) Groups of persons in which 2 or more persons have culture-confirmed anthrax (and therefore common-source exposure is likely or plausible).. PEP should be offered until exposure is confirmed or ruled out or for 60 days (See Treatment Section.) ii) Groups of persons in which 1 person has culture-confirmed anthrax and an associated environmental source is also culture positive. PEP should be offered until exposure is Page 4

5 confirmed or ruled our or for 60 days. iii) Groups of persons undergoing investigation for possible exposure (e.g., environmental sampling). PEP should be offered for 5-10 days pending laboratory results and a final recommendation. 9) Treatment of Cases: Recommend to the State Health Commissioner that cases should be recommended for treatment according to current guidelines (See Treatment Section.) Disease Prevention Objectives Prevent disease in high risk populations through: o Education of personnel in the proper use of protective clothing and respirators prior to entry into exposed areas or prior to direct contact with contaminated items or equipment. Disease Control Objectives Prevent unnecessary illness and death through rapid identification of populations exposed to anthrax so appropriate treatment or post exposure prophylaxis can quickly be administered. Surveillance Objectives Rapidly detect and confirm a case or outbreak of anthrax if it occurs in WV. Public Health Significance In the U.S., the incidence of naturally acquired anthrax is extremely low. Two hundred twenty-eight cases of naturally occurring cutaneous cases occurred in the U.S. from One further case was reported in Eighteen cases of naturally occurring inhalational anthrax occurred from 1900 through 1976; an additional case associated with handling imported animal hides was reported in Gastrointestinal anthrax is rare but may occur in association with ingestion of infected animals. Historically, the last reported case of anthrax in humans in WV occurred in In the fall of 2001, however, 11 cases of inhalational anthrax and 11 cases of cutaneous anthrax were linked to B. anthracis sent through the mail. This attack on citizens of the U.S. demonstrated that intentional release of anthrax spores through the mail is possible and highlights the need for public health preparedness to meet the challenge of bioterrorism. Page 5

6 Clinical Description presents as three somewhat distinct clinical syndromes in humans: cutaneous, inhalational, and gastrointestinal disease. Cutaneous: The cutaneous form (also referred to as a malignant pustule) occurs most frequently on the hands, neck, and forearms of persons working with infected livestock. Ninety-five percent of anthrax infections occur when the bacterium enters a cut or abrasion on the skin, such as when handling contaminated wool, hides, leather, or hair products of infected animals. It begins as a papule, i.e. a raised itchy bump, but within 1-2 days develops into a fluid-filled vesicle, and then progresses to a painless ulcer (usually 1-3 cm in diameter) with a characteristic black necrotic (dying) area in the center. The vesicle typically dries and forms a coal-black scab (eschar). This local infection can occasionally disseminate into lymph nodes and blood stream causing a fatal systemic infection. Inhalational: The clinical presentation of inhalational anthrax is a two-stage illness. In the first stage, patients develop a spectrum of non-specific symptoms, including fever, cough, headache, vomiting, chills, weakness or malaise, abdominal pain, and chest pain. In the second stage, symptoms progress and develop abruptly with sudden fever, dyspnea, diaphoresis, and shock. Massive lymphadenopathy and expansion of the mediastinum lead to stridor in some cases. X-ray may show a widened mediastinum consistent with lymphadenopathy, pulmonary infiltrates, and effusions. After several days, the symptoms may progress to severe breathing problems and shock. Up to half the patients may also have a hemorrhagic meningitis. In the first ten 2001 BT cases, all had abnormalities on chest X-ray: widened mediastinum was present in 7 cases, pleural effusions in 8 cases, and infiltrates in 6 cases. Gastrointestinal: may follow the consumption of contaminated meat and is characterized by an acute inflammation of the intestinal tract. Upper gastrointestinal disease or the oral-pharyngeal form results in oral or esophageal ulcers and leads to the development of regional lymphadenopathy, edema and sepsis. The lower gastrointestinal disease form manifests as primary intestinal lesions occurring predominantly in the terminal ileum or cecum. Initial signs of nausea, loss of appetite, vomiting, and fever are followed by abdominal pain, vomiting of blood, and severe diarrhea. Mortality may be high; however there is little information on gastrointestinal mortality rates in the absence of inhalational or cutaneous exposures. Etiologic Agent Bacillus anthracis, the causative agent of anthrax, is an aerobic, gram-positive spore-forming, nonmotile rod. The spores are the usual infective form. Page 6

7 Reservoir is primarily a zoonotic disease of herbivores, with cattle, sheep, goats, and horses being the usual animal hosts, but other animals may be infected. Mode of Transmission Humans generally contract the disease when handling contaminated hair, wool, hides, flesh, blood, or excreta of infected animals; when contacting contaminated soil; or when contacting contaminated manufactured products of animal origin. Infection is introduced by skin contact via scratches or abrasions, wounds, inhalation of spores, ingestion via eating insufficiently cooked infected meat, or possibly from biting flies that have fed on infected animals. With intentional exposure, as in a bioterrorist release, breathing in the spores or contact with an opening in the skin (cuts, scratches, abrasions, etc) have been the most likely routes of entry into the body. Discharges from cutaneous lesions are potentially infectious, but person-to-person transmission has not been documented. Accidental infections have occurred in laboratory workers. Incubation Period Symptoms generally develop between 1-7 days after exposure, but can occur up to 60 days after exposure. Onset of symptoms is dependent upon the dose and strain. Infectious Period Person-to-person transmission has not been documented. Prior to development of eschars, fluid from vesicles may be infectious and standard precautions should be taken when treating patients with cutaneous anthrax. Outbreak Recognition There has not been a human case of anthrax in WV since Thus, one case of anthrax constitutes an outbreak. Page 7

8 Case Definition Clinical Description An illness with acute onset characterized by several distinct clinical forms including the following: Χ Cutaneous: A skin lesion evolving during a period of 2-6 days from a papule, through a vesicular stage, to a depressed black eschar. Χ Inhalation: A brief prodrome (fever and malaise, and 1 or more nonspecific symptoms including cough, headache, vomiting, abdominal pain, and chest pain) resembling a viral respiratory illness followed by development of hypoxia, and dyspnea, with radiographic evidence of mediastinal widening or other chest x-ray abnormalities (e.g., lymphadenopathy, pulmonary infiltrates, or pleural effusion). Χ Gastrointestinal: Severe abdominal distress followed by fever and signs of septicemia. Χ Oral-pharyngeal: Mucosal lesion in the oral cavity or oropharynx, cervical adenopathy and edema, and fever. Laboratory criteria for diagnosis: Χ Isolation of B. anthracis from a clinical specimen, or Χ electrophoretic immunotransblot (EITB) reaction to the protective antigen and/or lethal factor bands in one or more serum samples obtained after onset of symptoms (i.e., lysis by gamma phage test), or Χ Demonstration of B. anthracis in a clinical specimen by immunofluorescence (i.e., direct fluorescence-antibody (DFA) assay or time-resolved fluorescence (TRF) testing.) Case classification Confirmed: a clinically compatible case that is laboratory confirmed. Laboratory Notes Environmental samples Environmental samples may be taken if possible and if appropriate for exposure assessment. Page 8

9 Consult IDEP ( ) or OLS ( ) before collection. Specimens The following clinical specimens may be collected for testing for B. anthracis: lymph node biopsy, vesicular fluid or eschar swab (for cutaneous anthrax), stool (gastrointestinal anthrax), blood and/or CSF for inhalational or other forms of anthrax. The clinician should consult his/her clinical laboratory about guidance for specimen collection. Clinical laboratories should consult the Office of Laboratory Services ( ) about specimen collection and confirmatory testing. Preventive Interventions 1) Personal protective equipment (PPE): Proper PPE, including clothing and respirator use must be employed by all personnel who are exposed to B. anthracis by entering an environmentally contaminated exposure zone in a BT event. Untrained and unprotected personnel should NOT enter a contaminated zone until decontamination is complete. 2) Infection Control Procedures: Standard precautions are recommended for patient care. 3) In the event of a naturally occurring case of anthrax, remove people from the source of infected livestock, wool, hide, or leather products, etc. 4) Decontamination of the environment is technically difficult and should be undertaken only with expert guidance. 5) Management of deceased persons or animals with anthrax: a) Cremation is recommended. Embalming may be associated with special risks. b) If autopsy is performed, CDC can offer guidance on conducting autopsies. All instruments should be autoclaved or incinerated. Treatment During the 2001 bioterrorist anthrax mailings 5 of 11 patients died from inhalational anthrax. Prior to that time, mortality was 92% in published cases. Reductions in mortality are associated with early treatment with multiple effective antibiotics. Mortality is very high with onset of meningitis or other signs of fulminant infection. Without antibiotic therapy, the mortality rate for cutaneous anthrax has been reported to be as high as 20%; with appropriate antibiotic treatment, death due to cutaneous anthrax is rare. In summary, rapid post exposure prophylaxis and treatment is essential. Page 9

10 Treatment protocols for inhalational and cutaneous anthrax are shown in the tables below for the contained casualty setting (a few cases), mass casualty setting and cutaneous anthrax. Oral administration of antibiotics is recommended in a mass casualty setting in which supplies and resources are exhausted. Intravenous administration is preferred when feasible. Page 10

11 Reference: JAMA, May 1, 2002; Vol 288, pp

12 Reference: JAMA, May 1, 2002; Vol 288, pp

13 Reference: JAMA, May 1, 2002; Vol 288, pp

14 Adverse Events Adults: During October 26-November 6, 2001, evaluation of adverse events associated with antimicrobial prophylaxis was conducted among 8,424 postal employees who had been offered antimicrobial prophylaxis for 60 days in NJ, NYC, and Washington, D.C. (MMWR, Nov. 30,2001, vol 50,no 47, pages ) Questionnaires were administered 7 to 10 days after individuals first took the prophylaxis. Of the 3,428 persons who had taken ciprofloxacin, 1666 (19%) reported severe nausea, vomiting, diarrhea, or abdominal pain, 484 (14%) reported fainting, light-headedness, or dizziness; 250 (7%) reported heartburn or acid reflux; and 216 (6% reported rashes, hives, or itchy skin.) Of 3,863 persons on any medication for antimicrobial prophylaxis, 83 (2%) sought medical attention for symptoms that may have been associated with anaphylaxis (i.e., difficulty breathing; throat tightness and difficulty swallowing; swelling of lips, tongue, or face; and rash, hives, and itchy skin). Of the 33 persons who sought medical attention for these symptoms, none were hospitalized and none of the symptoms were attributed to the treatment by their clinicians. Children: The American Academy of Pediatrics has recommended that doxycyline not be used in children younger than 9 years because the drug has resulted in retarded skeletal growth infants and discolored teeth in infants and children. However, the serious risk of infection following an anthrax attack supports the consensus recommendation that doxycycline, instead of ciprofloxacin, be used in children if antibiotic susceptibility testing, exhaustion of drug supplies, or adverse reactions preclude use of ciprofloxacin (JAMA, May 1, 2002). Pregnant women: Fluoroquinolones (e.g., ciprofloxacin) are not generally recommended during pregnancy because of their association with arthropathy in adolescent animals and small numbers of children. Animal studies have documented no evidence of teratogenicity related to ciprofloxacin, but no controlled studies of ciprofloxacin in pregnant women have been conducted. Balancing these risk against the concerns of anthrax due to a bioterrorist attack, pregnant women should receive ciprofloxacin as part of combination therapy for treatment of inhalational anthrax (JAMA, May 1, 2002). Page 14

15 The tetracycline class of antibiotics has been associated with both toxic effects in the liver in pregnant women and fetal toxic effects, including retarded skeletal growth. Balancing the risk of anthrax with those associated with doxycycline use in pregnancy, the working group recommends that doxycycline can be used as an alternative to ciprofloxacin as part of combination therapy in pregnant women for treatment of inhalational anthrax. For postexposure prophylaxis or in mass casualty settings, doxycycline can also be used as an alternate to ciprofloxacin in pregnant women. Ciprofloxacin and doxycycline can be excreted in breast milk and thus breast feeding women should be treated with the same antibiotics based on what is most safe and effective for the infant. Immunosuppressed persons: The antibiotic treatment of postexposure prophylaxis for anthrax among immunosuppressed has not been studied in human or animal models of anthrax infection. Antibiotics are to be administered in the same regimens recommended for immunocompetent adults and children. Surveillance Indicators 1) Time between suspicion of anthrax and first report to public health. 2) Completeness of investigation including risk factor and exposure data collection. 3) Time between suspicion of anthrax and completion of clinical history. 4) Time between suspicion of anthrax and completion of risk factor and exposure data collection. 5) Time from suspicion of anthrax and identification of source of exposure. References 1) Bartlett JG, Inglesby TV and Borio L. Management of anthrax. Clin Infect Dis, 2002; 35: ) Centers for Disease Control and Prevention. Human anthrax associated with an epizootic among livestock North Dakota, MMWR, 2001; 50: ) Centers for Disease Control and Prevention. Update: adverse events associated with anthrax prophylaxis among postal employees New Jersey, New York City, and the District of Columbia Metropolitan Area, MMWR, 2001; 50: ) Centers for Disease Control and Prevention. Inhalation anthrax associated with dried animal hides Pennsylvania and New York City, MMWR, 2006; 55: ) Dixon TC, Meselson M, Guillemin J, and Hanna PC.. New Engl J Med, 1999; 341:815- Page 15

16 826. 6) Holty Jc, Bravata DM, Liu H, et.al. Systematic review: a century of inhalational anthrax cases from 1900 to Ann Intern Med, 2006; 144: ) Inglesby TV, OToole T, Henderson DA, et.al. as a biological weapon, 2002: updated recommendations for management. JAMA, 2002; 288: ) Jernigan DB, Raghunathan PL, Bell BP, et.al. Investigation of bioterrorism related anthrax, United States, 2001:epidemiologic findings. Emerg Infect Dis, 2002; 8: ) Shafazand S, Doyle R, Ruoss S, Weinacker A, and Raffin TA. Inhalational anthrax: epidemiology, diagnosis and management. Chest, 1999; 116: ) Swartz MN. Recognition and management of anthrax an update. New Engl J Med, 2001; 345: ) Meselson M, Guillemin J, Hugh-Jones M, et.al. The Sverdlovsk anthrax outbreak of Science, 1994; 266: Page 16