An investigation of a deadly influenza outbreak at a residential facility in Ohio underscores the importance of clinicians being particularly attentive to signs of flu in children and young adults with neurologic and neurodevelopmental conditions.
Ten people were hospitalized and seven died after flu broke out in February 2011 at a residential facility where 130 children and young adults lived.
“Children and young adults with neurologic and neurodevelopmental conditions have increased risk for severe illness and complications from seasonal influenza, including death,” the authors of the report wrote in the Jan. 6 edition of Morbidity and Mortality Weekly Report(MMWR) from the Centers for Disease Control and Prevention (CDC).
Michael Jhung, MD, of the CDC Influenza Division, told Neurology Today that the deadly flu outbreak at the Ohio facility should prompt residential facilities to have a clear strategy in place for dealing with influenza, including vaccinations, testing, infection control and timely use of antiviral agents to ward off complications such as pneumonia.
Dr. Jhung, who helped investigate the Ohio outbreak, said lessons learned from that case also have relevance for clinicians who care for patients in the community. He noted, for instance, that respiratory symptoms such as coughing might not seem suspicious in patients with underlying conditions that cause coughing and compromised breathing. In addition, communication barriers may prove to be a hindrance to early diagnosis of influenza. “Patients may be unable to communicate that they have a sore throat or muscle aches or a headache,” symptoms typical of flu, Dr. Jhung said.
Dr. Jhung said prompt testing for flu and “early and aggressive use” of antiviral treatment is critical to reducing the possibility of severe complications in such patients.
THE OHIO CASE
A team from the CDC and the Ohio Department of Health investigated the flu outbreak that occurred in February 2011 at the Ohio residential facility. Of the 130 children and young adults who lived at the home, 76 had acute onset of respiratory illness, according to the MMWR report. Thirteen of the residents were severely ill, including seven with confirmed influenza and six with suspected influenza. The median age of the severely ill residents was 22, and they were sick for an average of 18 days. All 13 of the severely ill residents had severe to profound neurologic and neurodevelopmental disabilities, including physical limitations — scoliosis, hemiplegia or quadriplegia, cerebral palsy — and nine had “do not resuscitate orders.” All had received the 2010-2011 seasonal flu vaccine the previous fall.
Fever was the most common clinical sign at illness onset and respiratory failure was the most common hospital discharge diagnosis/cause of death, the CDC investigators reported. The report included two case studies — one of a patient who developed severe respiratory complications and died on day 8 of his illness, another involving a patient who recovered after eight days of hospitalization for respiratory problems.
“The 13 children and young adults with severe influenza illnesses in this outbreak likely would have benefited from earlier treatment with influenza antiviral medication,” according to an editorial note that accompanied the MMWR report.
“Although eight residents received antiviral treatment, oseltamivir was initiated within 48 hours of illness onset in only four cases. Treatment with a neuraminidase inhibitor is best started within 48 hours of symptom onset; however, recent observational data indicate that, even when started more than 48 hours after illness onset, treatment can help prevent influenza-related complications and death in persons at higher risk or with more severe illness.”
That said, the investigators noted that early diagnosis can be difficult. “Clinicians might encounter challenges in diagnosing influenza in persons with severe neurologic or neurodevelopmental conditions because patients might have only subtle deviations from their baseline medical status and be unable to communicate symptoms effectively,” according to the MMWR report.
Patients might already have “impaired pulmonary function resulting from muscle abnormalities or conditions such as severe scoliosis. They might, therefore, be less able to clear pulmonary secretions and be at increased risk for subsequent lower respiratory tract infection.”
USE ANTIVIRALS PROMPTLY
The report noted that because influenza can appear as a nonspecific respiratory illness, “clinicians should consider co-administration of empiric antiviral and antibiotic treatment, if warranted.”
James J. Sejvar, MD, a neuroepidemiologist in the CDC Division of High-Consequence Pathogens and Pathology, said in an interview with Neurology To1/31/2012day that the Ohio case serves as a reminder that “when influenza is suspected there should be a low threshold for rendering treatment” in high-risk patients. While there are potential side-effects associated with antiviral therapy — nausea, vomiting, diarrhea, among them — they are uncommon and generally less risky than serious complications of the flu. According to the MMWR report, antiviral medication can also be helpful in containing an outbreak once it starts. Residential facilities should undertake “early use of influenza antiviral medication for treatment of person with suspected or confirmed influenza and for prevention in other residents and staff members as soon as an outbreak is identified,” it said.
The children and young adults in the Ohio facility had been given the seasonal flu vaccine in the fall of 2010, but that didn't stop the outbreak. Larry E. Davis, MD, a neuroinfectious disease expert who is a Distinguished Professor of Neurology at the University of New Mexico School of Medicine, told Neurology Today that vaccination “reduces the risk but does not eliminate the risk” of coming down with the flu. He said that because children with neurologic and neurodevelopmental conditions seem more prone to getting lower respiratory tract infections, “you want to cut viral replication as quickly as you can,” by use of antiviral medication.
Dr. Jhung said there is research to suggest that underlying weakness in the muscles that do the work of breathing may contribute to respiratory failure in such children who come down with the flu. There is also some research to suggest that such patients may have a diminished immune response to influenza vaccine.
“It's very preliminary, a small study, but there is evidence to suggest that folks with neurologic conditions may actually be immunosuppressed. They may not respond to the influenza vaccine as well or as strongly,” Dr. Jhung said.
The MMWR report noted that the children and young adults who lived in the Ohio residential facility may have been more medically fragile than children with neurologic disabilities who live with their families, thus making the report's findings difficult to generalize to all patients with neurologic and neurodevelopmental conditions or all patients who live in residential-care centers.
Still, Dr. Jhung said the CDC was stepping up its efforts to remind residential-care facilities that they should have an influenza strategy that focuses on both prevention and early testing and treatment to contain outbreaks.