Presentation/Incidence

US Incidence Data

The CDC publishes weekly H1N1 Influenza updates at www.cdc.gov/flu/weekly.  This site provides a wide vareity of useful charts, tables and maps that are useful and easily transfered to PPT presentations. The articles by Jain and Jamieson (in Resources) outline the best current data on H1N1 in US pregnant women.  These data indicate a 6-times greater mortality and 4-times greater rates of hospitalization and ICU admission for pregnant women.

California Incidence Data

The California Department of Public Health tracks California H1N1 Influenza disease activity at their site, with the data in a sub-page.  Here you may find weekly updates for severe H1N1 illness (hospitalizations, ICU cases and deaths). Starting September 27, H1N1 influenza data tables will be posted on a monthly basis.   Click here to see California Pandemic (H1N1) 2009 Virus Provisional Data Table.  This provides the Provisional Number of Pandemic (H1N1) 2009 Virus Hospitalizations, ICU and Fatal Cases in CA by Local Health Jurisdiction.  Pregnancy and Pediatric Cases were recently released and are shown below. (Thanks to Connie Mitchell, MD MPH Policy Development (CDPH-PCFH-MCH))

CA Pregnancy Data
 

 

Presentation of H1N1 in Pregnancy

The initial reports indicate that 98% of pregnant women with H1N1 influenza are febrile (>100F),  a higher rate than for non-pregnant adults, but this can not be exclusively relied on as recent clinical expereince suggests that fever may not always be present at disease onset.  This is a respiratory disorder so cough and sore throat are quite common.  Other symptoms include chills, body aches/muscle pain, headache, fatigue, runny nose, and occasionally diarrhea and vomiting.

Severe illness is typically a pneumonia that progresses to ARDS with superimposed bacterial pneumonia and respiratory failure.  All of the H1N1 deaths in pregnant women have followed this course.  The recent article in Obstetrics and Gynecology by Saleeby etal (in Resources) describes several severe cases in detail. 

The National Grand Rounds on H1N1 Influenza and Pregnancy has a number of useful slides describing incidence and presentation (it is in PPT format).