2010 — Sep-Aug 2011, pediatric influenza-associated deaths, 33 States — 115

–115 MMWR, CDC. “Influenza-Associated Pediatric Deaths…” 60/36, p. 1233-1238, 9-16-2011.

Narrative Information

CDC: Influenza-associated pediatric mortality has been a nationally notifiable condition since October 2004. This report summarizes the 115 cases of influenza-associated pediatric mortality reported to CDC that occurred from September 1, 2010, through August 31, 2011. Deaths occurred in 33 states. Nearly half of the deaths (46%) occurred in children aged <5 years. Of the children who died, 49% had no known Advisory Committee on Immunization Practices (ACIP)--defined* high-risk medical conditions, and 35% died at home or in the emergency department. Of the 74 children aged ≥6 months for whom vaccination data were available, 17 (23%) had been fully vaccinated. ACIP recommends that all children aged ≥6 months receive vaccination against influenza annually... These findings underscore the importance of vaccinating children to prevent influenza virus infection and its potentially severe complications. Health-care providers should develop a comprehensive strategy to increase vaccination coverage among children. “A case is defined as a death from a clinically compatible illness confirmed to be influenza by a diagnostic test in a U.S. resident aged <18 years, with no period of complete recovery between illness and death. Cases are identified by state and local health departments, which collect demographic, clinical, and laboratory information using a standard form and transmit the information to CDC via a secure, web-based interface for data entry. Confirmatory influenza testing methods include commercial rapid diagnostic tests, viral culture, fluorescent antibody, enzyme immunoassay, reverse transcription--polymerase chain reaction, and immunohistochemistry. Although influenza vaccination of women during pregnancy has been shown to be effective in reducing hospitalizations (1) and deaths among infants aged <6 months (3), data on maternal vaccination during pregnancy were not available for infants aged <6 months. “Of the 115 influenza-associated pediatric deaths reported, 72 (63%) occurred in males… The majority of cases were in non-Hispanic white children (52%), followed by non-Hispanic black (18%) and Hispanic (15%) children. The highest numbers of deaths occurred in late January and early February 2011…The median age of patients was 6 years, and 53 cases (46%) were in children aged <5 years... Seventy-one (62%) of these cases were associated with influenza A virus infection: 30 (26%) 2009 influenza A (H1N1), 21 (18%) influenza A (H3N2), and 20 (18%) influenza A viruses for which the subtype was not determined. The remaining 44 (38%) cases were associated with influenza B virus infections. In comparison, U.S. national viral surveillance data from World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories indicated that 74% of circulating viruses were influenza A and 26% were influenza B viruses. “….Information on the location of death was available for 114 children; 20 (18%) died outside the hospital, 20 (18%) died in the emergency department, and 74 (65%) died in the hospital after admission… Duration of illness ranged from 0 to 57 days…; 33 (31%) children died within 3 days of illness onset, and 69 (65%) died within 7 days. When compared with pediatric deaths among children with at least one ACIP-defined high-risk condition, children without high-risk conditions were significantly more likely to die at home or in the emergency department (p<0.01 by chi-square test). The median illness duration before death was 7 days among children with at least one ACIP-defined high-risk condition and 4 days among children without a high-risk condition…. “Information about influenza vaccination was available for 74 children aged ≥6 months; 17 (23%) received influenza vaccine in the appropriate number of doses at least 14 days before illness onset. Of 39 vaccine-eligible children with ACIP-defined high-risk medical conditions who had vaccination data available, 12 (31%) had been vaccinated according to 2010 ACIP recommendations. “Reported by: World Health Organization Collaborating Center for Surveillance, Epidemiology, and Control of Influenza. Lenee Blanton, MPH, Rosaline Dhara, MPH, Lynnette Brammer, MPH, Joseph Bresee, MD, Nancy Cox, PhD, Lyn Finelli, DrPH, Influenza Div, National Center for Immunization and Respiratory Diseases; Karen K. Wong, MD, EIS officer, CDC. “Editorial note: “….This report highlights several important points about influenza epidemiology, vaccination, and treatment in children. Although influenza-associated pediatric mortality is rare, influenza B was identified in a disproportionate number of pediatric influenza-associated deaths (38%). During the 2010--11 influenza season, only 26% of circulating influenza viruses were influenza B. In previous seasons, the percentage of influenza B viruses among children with influenza-associated mortality has been comparable to or higher than the percentage of influenza B viruses circulating for that season… “Annual influenza vaccination for all children aged ≥6 months is recommended and is the most effective way to prevent influenza and its complications. Influenza vaccination campaigns should proceed for all persons (children and adults) as soon as vaccine is available. Since 2010, ACIP has recommended annual influenza vaccination for all persons aged ≥6 months, and children with ACIP-defined high-risk medical conditions should be specially targeted for vaccination… Healthy children aged 2--18 years may receive either live, attenuated influenza vaccine (LAIV) or trivalent inactivated influenza vaccine (TIV)... Children aged 6--23 months and those aged 2--4 years who have asthma or wheezing, or who have medical conditions that put them at higher risk for influenza complications should receive TIV... Children aged 6 months--8 years who did not receive at least 1 dose of the 2010--11 seasonal influenza vaccine should receive 2 doses of the 2011--12 seasonal influenza vaccine administered at least 4 weeks apart. Children in this age group who did receive at least 1 dose of the 2010--11 vaccine, as well as persons aged ≥9 years, should receive 1 dose of the 2011--12 vaccine… “In the United States, influenza vaccination coverage for the 2010--11 season was estimated at 49% in children aged 6 months--17 years… Among children who died from influenza described in this report, 23% were vaccinated. Vaccination coverage was higher among children with ACIP-defined high-risk medical conditions than among children without high-risk medical conditions (31% versus 12%). These findings emphasize the need to improve vaccination coverage among all children, especially those at increased risk for influenza-related complications. To protect infants aged <6 months who are too young to be vaccinated, ACIP recommends that pregnant women (3) and household contacts and out-of-home caregivers of such infants receive vaccination against influenza...Because influenza vaccination of women during pregnancy has been shown to be effective in reducing hospitalizations…and deaths among infants aged <6 months (3), improving vaccination rates among pregnant women is a priority….” Source MMWR (Morbidity and Mortality Weekly Report), Centers for Disease Control and Prevention. Vol. 60, no. 36, pp. 1233-1238, 9-16-2011. Accessed 1-11-2022 at: https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6036a1.htm