Wheezing Illness in Children with Asthma Aged 1.5 to 4 Years After Live Attenuated Influenza Vaccine (LAIV), Central Texas Field Trial, 1998-2002

Pedro A. Piedra, MD W. Paul Glezen, MD

Baylor College of Medicine, Houston, Texas

Manjusha J. Gaglani, MBBSMark Riggs, PhD

Scott & White Memorial Hospital and ClinicTAMU Health Science Center, Temple, Texas

Criteria for LAIV on enrollment in the TrialPiedra et al: Pediatrics 2005; 116:e397-e407

Healthy Children, 1.5 to 18 years of age, without immunocompromized household contact

Children with mild intermittent asthma were included

Definition: Mild intermittent asthma was defined as history of asthma or reactive airway disease (RAD) not requiring daily (or every other day) use of steroids (oral or inhaled) or bronchodilator therapy for asthma control, not hospitalized or seen in the emergency room for asthma in the prior 12 months (prior 6 months if they were < 2 years old).

Children with exercise-induced asthma were included.

Children with allergic rhinitis on daily nasal steroids were included.

[Others were offered inactivated influenza vaccine if not allergic to eggs.]

Year 1.5 - 4 years of ageRAD* No RAD

Pre-School Children with a History of Asthma/Reactivate Airway Disease (RAD) Who Received the Live Attenuated Influenza Vaccine (LAIV) in the

Central Texas Field Trial, Scott & White Clinic (SWC). 1998-2002

*identified by parent history, medical record or both (about 1/3 in each group)

1998-99 138 7121999-00 192 7832000-01 167 7182001-02 109 607

Relative Risk of Medically Attended Acute Respiratory Illness (MAARI) 1 - 14 Days after LAIV for Children 1.5 – 4

Years of Age with RAD, Central Texas Field Trial, 1998-2002.

Year 1 – 14 days post-LAIV* Pre-LAIV & >14 Days RR Post-LAIV (reference)* 95% CI

1998-99 51.9 110.3 0.490.26, 0.92

1999-00 90.1 119.8 0.740.48, 1.12

2000-01 116.5 128.6 0.950.62, 1.44

2001-02 19.8 78.6 0.250.08, 0.81

*Rate per 10,000 child-days

Relative Risk of Lower Respiratory Illness (LRI) 1 – 14 Days after LAIV for Children 1.5 – 4 Years of Age with RAD,

Central Texas Field Trial, 1998 – 2002.

Year 1 – 14 days post-LAIV* Pre-LAIV & >14 Days RR Post-LAIV (reference)* 95% CI

1998-99 5.2 16.3 0.320.04, 2.34

1999-00 3.8 10.7 0.390.05, 2.90

2000-01 12.9 24.0 0.590.17, 1.97

2001-02 0.0 9.2 n/a

*Rate per 10,000 child-days

Relative Risk of Asthma/RAD Events 1 – 14 Daysafter LAIV for Children 1.5 – 4 Years of Age with RAD

Central Texas Field Trial, 1998 – 2002.

Year 1 – 14 days post-LAIV* Pre-LAIV & >14 Days RR Post-LAIV (reference)* 95% CI

1998-99 10.4 18.7 0.600.14, 2.50

1999-00 15.0 18.4 0.800.28, 2.26

2000-01 8.6 12.0 0.700.16, 3.19

2001-02 0.0 3.1 n/a

*Rate per 10,000 child-days

Relative Risk of Medically Attended Acute Respiratory Illness (MAARI) 1 – 42 Days after LAIV for Children 1.5 – 4 Years of

Age with RAD Central Texas Field Trial, 1998 – 2002.

Year 1 – 42 days post-LAIV* Pre-LAIV & >42 Days RR Post-LAIV (reference)* 95% CI

1998-99 78.3 123.4 0.640.46, 0.88

1999-00 111.8 108.0 0.940.73, 1.23

2000-01 126.2 114.9 1.120.82, 1.53

2001-02 49.3 101.2 0.550.32, 0.93

*Rate per 10,000 child-days

Relative Risk of Lower Respiratory Illness (LRI) 1 – 42 Days after LAIV for Children 1.5 – 4 Years of Age with RAD

Central Texas Field Trial, 1998 – 2002.

Year 1 – 42 days post-LAIV* Pre-LAIV & >42 Days RR Post-LAIV (reference)* 95% CI

1998-99 17.4 17.7 0.920.45, 1.90

1999-00 6.3 11.3 0.580.21, 1.58

2000-01 23.2 17.1 1.310.61, 2.84

2001-02 2.2 12.5 0.130.01, 1.06

*Rate per 10,000 child-days

Relative Risk of Asthma/Reactive Airways Disease (RAD)1 – 42 Days after LAIV for Children 1.5 – 4 Years of Age with

RAD, Central Texas Field Trial, 1998 – 2002.

Year 1 – 42 days post-LAIV* Pre-LAIV & >42 Days RR Post-LAIV (reference)* 95% CI

1998-99 7.0 17.7 0.410.14, 1.16

1999-00 21.4 12.3 1.710.89, 3.29

2000-01 10.2 12.2 0.740.26, 2.10

2001-02 0.0 12.5 n/a

*Rate per 10,000 child-days