Deadly: new, virulent virus circulating in US

Washington

On May 16, 2007, the Tacoma-Pierce County Health Department notified the Washington State Department of Health (WADOH) of four residents housed in one unit of a residential-care facility who had been hospitalized recently for pneumonia of unknown etiology. The patients were aged 40--62 years; three of the four were female. One patient had acquired immunodeficiency syndrome (AIDS); the three others had chronic obstructive pulmonary disease. All four were smokers.

The patients had initial symptoms of cough, fever, or shortness of breath during April 22--May 8, 2007. Three patients required intensive care and mechanical ventilation for severe pneumonia. After 8 days of hospitalization, the patient with AIDS died; the other patients recovered. Respiratory specimens from all four patients tested positive for adenovirus by PCR at the WADOH laboratory; isolates were available from three patients, and all three isolates were identified as Ad14 by CDC. Ad14 had last been identified in an isolate from a patient from Washington in May 2006, marking the first identification of Ad14 in the state since 2004. Active surveillance among facility residents and staff did not identify any other cases of Ad14 illness.

Texas

Since February 2007, an outbreak of cases of febrile respiratory infection* associated with adenovirus infection has been reported among basic military trainees at Lackland Air Force Base (LAFB). During an initial investigation, conducted from February 3 to June 23, out of 423 respiratory specimens collected and tested, 268 (63%) tested positive for adenovirus; 118 (44%) of the 268 were serotyped, and 106 (90%) of those serotyped were Ad14. Before this outbreak, the only identification of an Ad14 isolate at LAFB occurred in May 2006 (1).

During February 3--June 23, 2007, a total of 27 patients were hospitalized with pneumonia (median hospitalization: 3 days), including five who required admission to the ICU. One ICU patient required extracorporeal membrane oxygenation for approximately 3 weeks and ultimately died. All 16 hospitalized patients from whom throat swabs were collected, including the five patients admitted to the ICU, tested positive for Ad14. Fifteen of these hospitalized patients tested negative for other respiratory pathogens, and one patient had a sputum culture that was positive for Haemophilus influenzae.

All health-care workers from hospital units where trainees had been admitted were offered testing for Ad14, regardless of history of respiratory illness. Of 218 health-care workers tested by PCR, six (3%) were positive for Ad14; five of the six reported direct contact with hospitalized Ad14 patients.

Prevention measures implemented during the outbreak included increasing the number of hand-sanitizing stations, widespread sanitizing of surfaces and equipment with appropriate disinfectants, increasing awareness of Ad14 among trainees and staff members, and taking contact and droplet precautions for hospitalized patients with Ad14. Beginning on May 26, trainees with febrile respiratory illness were confined to one dormitory and both patients and staff members were required to wear surgical masks.

Cases reported postinvestigation. Since the investigation, new cases of febrile respiratory illness have continued to occur at LAFB, but the weekly incidence has declined from a peak of 74 cases with onset during the week of May 27--June 2, to 55 cases with onset during the week of September 23--29 (the most recent period for which data were available). In addition, during March--September 2007, three other military bases in Texas that received trainees from LAFB reported a total of 220 cases of Ad14 illness (Air Force Institute for Operational Health, personal communication, 2007). However, whether Ad14 spread from LAFB to these three bases has not been determined. Ad14 also was detected in April in an eye culture from an outpatient in the surrounding community who had respiratory symptoms and conjunctivitis. No link between this case and the LAFB cases was identified.

posted by Medclincian

Reported by: Oregon Dept of Human Svcs. Washington State Dept of Health Communicable Diseases. 37th Training Wing, 59th Hospital Wing, Air Force Institute for Operational Health, Epidemic and Outbreak Surveillance, US Air Force. Naval Health Research Center, US Navy. Texas Dept of State Health Svcs. New York City Dept of Health and Mental Hygiene. Div of Viral Diseases, National Center for Immunization and Respiratory Diseases; Div of Healthcare Quality Promotion, National Center for Preparedness, Detection, and Control of Infectious Diseases; Career Development Div, Office of Workforce and Career Development, CDC.