Unexplained Critical Illnesses and Deaths of Possible Infectious Etiology, 2006

Surveillance for unexplained critical illnesses and deaths of possible infectious etiology began in September 1995. Any case should be reported, regardless of the patient’s age or underlying medical conditions. A subset of cases (persons up to 49 years of age with no underlying medical conditions who died of apparent non-nosocomial infectious processes) are eligible for testing performed at CDC as part a special project. For cases not eligible for the CDC project, some testing may be available at MDH or CDC, at the physician’s request. Forty-five cases (36 deaths and nine critical illnesses) were reported in 2006, compared to 67 cases in 2005. The cause(s) of illness subsequently were determined for nine cases. Among the remaining 36 cases, 12 case-patients presented with respiratory symptoms; three presented with shock/sepsis; five presented with neurologic symptoms; eight presented with cardiac symptoms; three presented with sudden unexpected death (SUD); four presented with gastrointestinal (GI) symptoms; and one had an illness that did not fit a defined syndrome. Case-patients with respiratory symptoms ranged from 1 month to 48 years of age; those with sepsis were 1 month to 58 years of age; the neurologic case-patients were 1 year to 59 years of age; the cardiac case-patients were 1 month to 45 years of age; the case-patients with GI symptoms were 4 to 47 years of age; the case-patients with sudden unexpected death were 2 months to 35 years of age; and the case-patient without a defined syndrome was 41 years of age. Ten patients with respiratory symptoms, two patients with sepsis, three patients with neurologic symptoms, five patients with a cardiac syndrome, and three patients with a GI syndrome died, as did the patient without a defined syndrome. Eighteen patients resided in the metropolitan area, 12 case-patients resided in Greater Minnesota, three case-patients were out-of-state residents hospitalized in Minnesota, and residence for three case-patients was unknown.

Twenty-one cases were eligible for the CDC project (nine respiratory, one sepsis, two neurologic, four cardiac, and four GI cases; and one SUD). Specimens were obtained for testing at MDH or CDC for 14 cases. Probable etiologies were established for three cases. A 4-year-old male who died with GI symptoms had immunohistochemical testing of the small intestine that was positive for rotavirus. A 39-year-old male who died with a respiratory syndrome had positive PCR tests of lung samples and a nasopharyngeal swab for metapneumovirus. A 47-year-old female who died with GI symptoms had a positive PCR result for norovirus from a stool sample. Positive PCR results for three other cases were of unknown significance.

Testing was also provided at MDH and/or CDC at the physician’s request for eight of the 15 cases that were not eligible for the CDC project. Positive results were found for two of these cases. A PCR for Epstein-Barr virus was positive in a blood sample of a 9-year-old male with myocarditis and a PCR for parainfluenza 3 was positive in a bronchial wash specimen of a 7-year-old female with myocarditis. The significance of these results is unknown.

Medical Examiner Surveillance Summary

In September 2006, MDH began a medical examiner (ME) surveillance program in Minnesota to collect reports of all deaths possibly due to infectious diseases that were reported to the ME’s Office. Our program was based on the New Mexico Office of the Medical Investigator, National Association of Medical Examiners, and CDC programs titled: “Medical Examiner/Coroner-based Surveillance for Fatal Infectious Diseases and Bioterrorism”. The surveillance program was piloted in 2006 at the Minnesota Regional Coroner’s Office, in Hastings. This Office covers seven counties, including Carver, Chisago, Dakota, Houston, Fillmore, Goodhue, and Scott, which together make up 14.3% of the state population.

There are two main components to the program. First, we increased the collection of samples taken at autopsy from cases with possible infectious disease signs or symptoms at the time of death or upon autopsy. MDH distributed specimen collections kits to the ME Office to help guide the number and type of specimens collected. These specimens were tested at the facility laboratory or sent to MDH for testing. In addition, MDH consulted with CDC on unexplained cases. There were approximately 10 kits distributed. Use of these kits improved the quality and number of specimens sent to MDH, which aided in determining a possible infectious disease cause of death.

The other main component to the program was a review of all death reports from 2006 at the ME Office to determine any other possible infectious disease deaths not already reported to MDH. There were 1,563 death reports reviewed at the Minnesota Regional Coroner’s Office. Of these, 56 (4%) were determined to be ME infectious disease surveillance cases, which means there were signs or symptoms of an active infectious disease at the time of death or upon autopsy, or it was an unexplained death in someone <50 years of age. There were 16 (29%) deaths determined to be due to infectious disease causes, 28 (50%) were possibly due to infectious disease causes, seven (13%) were not due to infectious disease causes, and five (9%) were unable to be determined because there was no anatomic cause of death. Cases were determined to be possible infectious disease causes if an infectious disease was a possible significant contributing cause of death or there was not enough information available to definitively attribute the cause of death to the infectious disease. Of the 16 deaths determined to be infectious disease related, eight did not have a pathogen specified, five were not vaccine preventable (two CJD, two HIV, and one HSV), and three were vaccine preventable (two S. pneumoniae, one N. meningitidis).

Of the 56 cases, 10 (19%) were reported to MDH as part of the unexplained deaths project. The ME also reported four additional cases, but these did not meet criteria for the unexplained deaths project. In addition, at least five cases were reported to MDH by the hospital, nursing home, or other care provider as part of the EIP. This means there were approximately 37 cases picked up by the ME active surveillance in addition to cases already reported to MDH, which represents 66% of the total cases found using the ME surveillance program.

• For up to date information see>> Unexplained Deaths and Critical Illnesses
  
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2006