Health Advisory
INFLUENZA-ASSOCIATED PEDIATRIC MORTALITY AND STAPHYLOCOCCUS AUREUS CO-INFECTION

CDC is requesting that states report all cases of influenza-related pediatric mortality during the 2007-2008 influenza season. This health advisory contains updated information about influenza and bacterial co-infections in children and provides interim testing and treatment recommendations.

Background

Since 2004, the Influenza-Associated Pediatric Mortality Surveillance System, part of the Nationally Notifiable Disease Surveillance System, has collected information on deaths among children due to laboratory-confirmed influenza, including the presence of other medical conditions and bacterial infections at the time of death. From October 1, 2006 through September 30, 2007, 73 deaths from influenza in children were reported to CDC from 39 state health departments and two city health departments. Data on the presence (or absence) of bacterial co-infections were recorded for 69 of these cases; 30 (44%) had a bacterial co-infection, and 22 (73%) of these 30 were infected with Staphylococcus aureus.

The number of pediatric influenza-associated deaths reported during 2006-07 was moderately higher than the number reported during the two previous surveillance years; the number of these deaths in which pneumonia or bacteremia due to S. aureus was noted represents a five-fold increase. Only one S. aureus co-infection among 47influenza deaths was identified in 2004-2005, and 3 co-infections among 46 deaths were identified in 2005-2006. Of the 22 influenza deaths reported with S. aureus in 2006-2007, 15 children had infections with methicillin-resistant S. aureus (MRSA).

The median age of children with S. aureus co-infection was older than children without S. aureus co-infection (10 years versus 5 years, p<.01) and children with co-infection were more likely to have pneumonia and Acute Respiratory Distress Syndrome (ARDS).Influenza strains isolated from these children were not different from common strains circulating in the community, and the MRSA strains have been similar to those associated with MRSA skin infection outbreaks in the United States.

Recommendations

Health care providers should test persons hospitalized with respiratory illness for influenza, including those with suspected community-acquired pneumonia. Health care providers should be alerted to the possibility of bacterial co-infection among children with influenza, and request bacterial cultures if children are severely ill or when community-acquired pneumonia is suspected. Health care providers should be aware of the prevalence of methicillin-resistant S. aureas strains in their communities when choosing empiric therapy for patients with suspected influenza-related pneumonia. Clinicians, health care providers, and medical examiners are asked to contact DPH (Division of Public Health) as soon as possible when deaths among children associated with laboratory-confirmed influenza are identified.

Influenza in Delaware

As of January 31, 2008, Delaware Division of Public Health (DPH) has confirmed 82 cases of Influenza distributed as follows; 43 cases from New Castle County, 27 from Kent County, and 12 from Sussex County. Distribution by sub-type is 55 are influenza A and 27 are influenza B.

The age range of the confirmed cases is 2 months to 72 years. No Influenza-associated pediatric deaths have been reported to DPH.

DPH has not been notified of any instances of bacterial co-infections related to influenza to date. We are requesting that when co-infections exist, they be reported along with the influenza morbidity report (see below).

Testing

DPH strongly encourages providers (hospitals, physicians, long term care facilities, school wellness centers, etc.) to submit influenza specimens to the DPH Laboratory for PCR, culture confirmation and sub typing (throat/NP/nasal wash) to assist with surveillance. Influenza testing by DPHL is done free of charge and results are sent back to the requesting organizations as soon as test results are available. To submit a specimen for culture, contact DPHL at (302-223-1520) to request influenza virus isolation kits and obtain information about specimen transport to the laboratory.

Reporting

Influenza and Influenza-Associated Pediatric Mortality are reportable conditions in Delaware. Healthcare providers can report cases of influenza by visiting the following website, printing out a copy of the morbidity report form and faxing it to the Bureau of Epidemiology at 302-739-1503. Morbidity reports can also be mailed. Providers may also contact the Bureau of Epidemiology at 302-739-4541 or 888-295-5156 with any questions or concerns regarding communicable disease reporting.

The list of Notifiable Diseases and Reporting Requirements may be viewed at:   http://www.dhss.delaware.gov/dhss/dph/dpc/rptdisease.html

For more information

• DPH Laboratory: (302) 223-1520
• DPH Immunization Hotline: 1-800-282-8672
• DPH Epidemiology: 1-888-295-5156 (Fax: 302-739-1503)
• CDC Influenza Division, Epidemiology and Prevention Branch: 404-639-3747.