Unusual pathogens ruled out in Alabama illness cluster

May 23, 2013 (CIDRAP News) – Test results on a cluster of Alabama patients hospitalized with similar respiratory symptoms indicated no unusual pathogens but instead a variety of common respiratory viruses and bacteria, state health officials announced today.

Don Williamson, MD, Alabama's state health officer, said in a statement from the Alabama Department of Public Health (ADPH)."This is good news. Testing has ruled out avian flu and novel coronavirus."

At a press briefing today Williamson said 10 patients at a hospital in Dothan, in the southeastern corner of the state  have been identified as part of the cluster, and so far tests results are available for 7 of them. Two patients have died, according to earlier reports.

Three of the seven patients had influenza A, four had rhinovirus, and three had bacterial pneumonia of different types, Williamson told reporters, indicating co-infection in at least some of the patients.

Six of seven patients had pneumonia on x-ray findings, and the seventh one was intubated, which suggests lower-respiratory involvement, he said.

Investigations found no common exposures or links between the patients. Williamson said it's uncommon to see flu in the spring, but it's not unheard of.

He said unusual cases, especially a cluster of them, trigger a closer look by public health officials. Williamson said health officials followed the proper procedures for reporting unexpected findings and patients who had common symptoms.

In March 2012 Maryland health officials identified a cluster of severe respiratory infections that had family connections. The patients were co-infected with H3N2 influenza and methicillin-resistant Staphylococcus aureus (MRSA).

Also, federal authorities have asked state and local health officials to be vigilant for unusual respiratory illness patterns, especially in people returning from China, where the novel H7N9 virus has sickened 131 people and killed 36 of them.

Earlier this month seven patients were admitted to the hospital, all with fever, cough, and shortness of breath, with no known cause for their illnesses, according to the ADPH, which requested that health providers send samples to the ADPH Bureau of Clinical Laboratories in Montgomery.

The illness cluster also triggered a May 21 alert for health providers to look for unusual respiratory infections and to submit samples from patients who fit the broad case definition.

Mary McIntyre, MD, MPH, assistant state health officer for disease control and prevention, said in the statement that enhanced surveillance is no longer necessary. "Health care providers are encouraged to continue routine year-round influenza surveillance activities and submit specimens to the state laboratory for testing."

Though nothing unusual was found in the cluster, the heightened surveillance strategy would be useful for quickly identifying a novel pathogen, if one had been involved, Williamson said.

The 10 patients in the cluster ranged in age from 24 years to 87 years, Williamson said. The patients who died were ages 34 and 55. A few of the patients have been released from the hospital, he added.

CIDRAP News thanks Mike Coston from Avian Flu Diary for his help in accessing the ADPH media briefing.

See also:

May 23 ADPH press release

May 22 CIDRAP News story "Alabama officials probe respiratory illness cluster"

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