A combination of influenza A, rhinovirus, and bacterial pneumonia – not avian influenza or a novel coronavirus – caused a cluster of serious respiratory illnesses that struck southeastern Alabama, according to state public health officials.
Testing that ruled out avian influenza and novel coronavirus for the cluster of cases, including some that were fatal, is “good news,” said State Health Officer Dr. Donald E. Williamson.
The state's department of health announced its findings in a statement issued May 23.
Earlier in May, seven people with unexplained fever, cough, and shortness of breath had been admitted to the hospital; two cases were fatal. Specimens in six of the seven patients were positive for influenza A, rhinovirus, or a combination of the two; and three patients had bacterial pneumonia, according to the statement. There were no pediatric cases; the ages of the patients ranged from the mid-20s to the 80s, a department spokesperson said.
Enhanced surveillance associated with the cluster of cases was no longer necessary, Dr. Mary McIntyre, assistant state health officer for disease control and prevention, said in the statement. But she encouraged health care providers “to continue routine year-round influenza surveillance activities and submit specimens to the state laboratory for testing.”
Influenza was most likely the main cause of the severe cases, infectious disease specialist Dr. William Schaffner said in an interview. The cluster illustrates that while influenza is a winter infection, it “remains capable of being transmitted and occurring in our population at very low levels” in the summer months, he cautioned.
The investigation of the Alabama cluster “reinforces the need for physicians to be alert constantly, to treat serious disease with respect, get those specimens and, in circumstances like this, at a drop of the hat, notify the public health department,” added Dr. Schaffner, professor and chair of the department of preventive medicine at Vanderbilt University, Nashville, Tenn.