Occupational Transmission of Neisseria meningitidis, California, 2009

Abstract & Commentary

By Mary-Louise Scully, MD

Dr. Scully is Director, Travel and Tropical Medicine Center, Sansum Clinic, Santa Barbara, CA.

Dr. Scully reports no financial relationships relevant to this field of study.

Synopsis: Prevention of occupational transmission of meningococcal disease depends on immediate reporting of suspect cases to local health authorities and the use of proper infection control measures by health-care and emergency responder personnel.

Source: Occupational transmission of Neisseria meningitidis, California, 2009. Morbid Mortal Wkly Rep 2010;59(45):1480-1483.

On December 11, 2009, the California Department of Public Health (CDPH) began an investigation into two secondary cases of meningococcal disease following occupational exposure to an unconscious adult. The index case was a 36-year-old male, and the secondary cases were a police officer and a respiratory therapist.

On December 3, 2009, four police officers arrived on the scene to find the index patient in bed, unconscious, with his airway partially obstructed by vomitus. One of the police officers (PO1) turned the patient to the side and adjusted the patient's head to aid in breathing. Immediately after, PO1 left the room and returned once, but never again within 3 feet of the patient. The index patient was then transferred to Hospital A, where a respiratory therapist (RT1) assisted with endotracheal intubation and suctioning. On December 4, gram-negative diplococci were identified in the index patient's CSF and several hours later in blood. On December 6, N. meningitidis was isolated from blood, and the following day from CSF. The patient was managed in the intensive-care unit (ICU), treated with appropriate antibiotics, and survived.

Forty-eight hours after PO1 assisted in the case, he began experiencing sore throat and nausea that eventually progressed to fever, vomiting, and muscle pain. He saw his primary care physician 4 days later (December 9), and after a colleague of PO1 called with information about possible meningitis exposure, PO1 was sent directly to Hospital B for admission and IV antibiotics. On Dec 10, gram-negative diplococci were identified in the blood of PO1, and the following day blood and CSF cultures were positive for N. meningitidis. PO1 was treated with IV antibiotics and discharged to home after 5 days in Hospital B.

On December 8 (5 days after exposure), RT1 had onset of weakness, chills, and fatigue. On December 11, gram-negative diplococci were identified in the blood and CSF of RT1, and the next day blood and CSF were culture-positive for N. meningitidis at Hospital C. After treatment with ceftriaxone, vancomycin, and meropenem, RT1 also survived and was discharged to home after 11 days of hospitalization.

N. meningitidis serogroup C, ST-11 clonal complex was isolated from both the index case and the two secondary cases, PO1 and RT1. The isolates were indistinguishable by pulse-field gel electrophoresis. The state of California requires health-care providers to report immediately by telephone any suspected cases of meningococcal disease to the local health authority. In the case of Hospital A, this report was delayed for 3 days. In addition, Hospital A did not conduct an exposure assessment of affected employees until 8 days post-exposure — essentially after learning of RT1's hospitalization. Hospital B's reporting was actually on time, but Hospital C's reporting was one day late. The other staff in the emergency room of Hospital A (one physician, 2 nurses, and another respiratory therapist) were offered post-exposure chemoprophylaxis (PEP) 8 days postexposure. Ideally PEP should be given < 24 hours or as soon as possible after an identified exposure. Two paramedics at the initial scene were offered PEP 4 days after exposure, and one firefighter at 5 days after exposure. Neither PO1 nor RT1 were ever contacted or offered PEP before their illnesses.

In the emergency room, neither the physician nor RT1 wore any type of mask or respirator during suctioning and the intubation procedure. Neither of the two nurses in the ER administering IV fluids and caring for the index patient wore any type of mask either. Another respiratory therapist caring for the patient did wear a surgical mask with a face shield. The emergency personnel performed better, with both paramedics and both firefighters wearing N95 respirators. PO1 wore only gloves.

Commentary

This is the first time more than one occupationally acquired case of meningococcal disease has occurred after exposure from the same index case. These three patients were indeed fortunate in that all survived — especially as case fatality rates for meningococcal meningitis and sepsis range from 10-14%.1

There were significant delays in notification to the local health authorities, worker exposure assessment, and timely use of PEP. There were also significant breaches in proper infection control policies by the emergency room staff.

The California Division of Occupational Safety and Health Aerosol-Transmissible Diseases (Cal/OSHA ATD) requires droplet precautions for all contact with suspected or confirmed cases of meningococcal disease.2 In the case of the index patient, the differential diagnosis included pandemic H1N1, so N95 respirators for airborne protection should have been used. As of September 2010, Cal/OSHA ATD is now recommending that employers provide a powered air-purifying respirator (PAPR) with a high-efficiency particulate air (HEPA) filter, or an equivalent respirator, to all employees who perform high-hazard procedures on patients with suspected airborne infectious diseases. The big obstacle to overcome will still be the human factor, i.e., the use of any such protective devices still will depend on health care personnel to actually wear them. However, the PAPR system seems more acceptable to health-care personnel.

PEP is recommended for close contacts of patients with meningococcal disease. The CDC Advisory Committee on Immunization Practices (ACIP) defines close contacts as: household members; child-care center personnel; and persons directly exposed to the patient's oral secretions (i.e., by kissing, mouth-to-mouth resuscitation, endotracheal intubation, or endotracheal tube management).1 Therefore, the policeman's (PO1) case is disconcerting, as his exposure was very brief and he did not recall any droplets on his skin or face. Infectious disease doctors often receive phone calls of this nature from our medical colleagues asking for advice. This report will no doubt influence our future decisions on similar cases that are outside the established parameters of meningococcal risk exposure.

References

  1. CDC. Prevention and control of meningococcal disease: Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbid Mortal Wkly Rep 2005; 54 (No. RR-7).
  2. CDC. 2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings. Atlanta GA: US Department of Health and Human Services, CDC:2007. Available at http://www.cdc.gov/ncidod/pdf/guidelines/isolation2007.pdf Accessed January 7, 2011.