◎Swine flu striking pregnant women hard: CDC study
ロイター Wed Jul 29, 2009
By Julie Steenhuysen
CHICAGO (Reuters) - Pregnant women infected with the new H1N1 swine flu have a much higher risk of severe illness and death, U.S. government researchers said on Wednesday, confirming a trend that has worried global health experts.
While pregnant woman have always had a higher risk of severe disease from influenza in general, the new H1N1 virus is taking an exceptionally heavy toll, the researchers said.
"We do see a fourfold increase in hospitalization rates among ill pregnant women compared to the general population," Dr. Denise Jamieson of the U.S. Centers for Disease Control and Prevention said in a telephone interview.
"We're also seeing a relatively large proportion of deaths among pregnant women. We report 13 percent in the paper, but that is a very unstable number based on a small number of deaths reported," said Jamieson, whose study appears in the journal Lancet.
The study was based on the deaths of six pregnant women out of 45 deaths related to H1N1 reported to the CDC between April 15 and June 16.
All of the women were healthy prior to infection, and all developed pneumonia and needed to be put on a ventilator.
Jamieson said 302 deaths have been officially reported to the CDC from the new H1N1 virus.
"Among those, we have relatively complete information on 266 deaths. And of those, 15 have been among pregnant women, which is about 6 percent," Jamieson said.
Given that at any point, about 1 percent of the U.S. population is pregnant, she said, pregnant women "are definitely over-represented in terms of the proportion of deaths."
She said pregnant women do not need to change the way they live because of the new H1N1 flu.
"There is no reason to delay pregnancy or to be overly concerned. We do not have evidence that pregnant women have increased susceptibility or are more likely to acquire influenza," Jamieson said.
"It's just that when they have influenza they are at increased risk of having severe disease," she said.
Jamieson said pregnant women who suspect they have influenza should call their doctors promptly.
And she said doctors need to provide a separate waiting area for pregnant women who suspect they are ill, to protect healthy pregnant women from infection.
Jamieson said pregnant women with influenza should be given antiviral drugs as soon as possible, within the first 48 hours to be most effective.
Despite recommendations from the Advisory Committee on Immunization Practices and the American College of Obstetricians and Gynecologists that all pregnant women get a seasonal flu shot, less than 14 percent do, according to the CDC.
The ACIP, which advises the CDC, is meeting later on Wednesday to decide who should be first to get the new H1N1 vaccine.
(Editing by Maggie Fox and Vicki Allen)
◎H1N1 2009 influenza virus infection during pregnancy in the USA
Denise J Jamieson MD a , Margaret A Honein PhD b, Sonja A Rasmussen MD b, Jennifer L Williams MSN b, David L Swerdlow MD c, Matthew S Biggerstaff MPH c, Stephen Lindstrom PhD c, Janice K Louie MD e, Cara M Christ MD f, Susan R Bohm MS g, Vincent P Fonseca MD h, Kathleen A Ritger MD i, Daniel J Kuhles MD j, Paula Eggers RN k, Hollianne Bruce MPH l, Heidi A Davidson MPH m, Emily Lutterloh MD d n, Meghan L Harris MPH o, Colleen Burke MSN p, Noelle Cocoros MPH q, Lyn Finelli DrPH c, Kitty F MacFarlane CNM a, Bo Shu MD c, Sonja J Olsen PhD c, the Novel Influenza A (H1N1) Pregnancy Working Group
Pandemic H1N1 2009 influenza virus has been identified as the cause of a widespread outbreak of febrile respiratory infection in the USA and worldwide. We summarised cases of infection with pandemic H1N1 virus in pregnant women identified in the USA during the first month of the present outbreak, and deaths associated with this virus during the first 2 months of the outbreak.
After initial reports of infection in pregnant women, the US Centers for Disease Control and Prevention (CDC) began systematically collecting additional information about cases and deaths in pregnant women in the USA with pandemic H1N1 virus infection as part of enhanced surveillance. A confirmed case was defined as an acute respiratory illness with laboratory-confirmed pandemic H1N1 virus infection by real-time reverse-transcriptase PCR or viral culture; a probable case was defined as a person with an acute febrile respiratory illness who was positive for influenza A, but negative for H1 and H3. We used population estimates derived from the 2007 census data to calculate rates of admission to hospital and illness.
From April 15 to May 18, 2009, 34 confirmed or probable cases of pandemic H1N1 in pregnant women were reported to CDC from 13 states. 11 (32%) women were admitted to hospital. The estimated rate of admission for pandemic H1N1 influenza virus infection in pregnant women during the first month of the outbreak was higher than it was in the general population (0·32 per 100 000 pregnant women, 95% CI 0·13—0·52 vs 0·076 per 100 000 population at risk, 95% CI 0·07—0·09). Between April 15 and June 16, 2009, six deaths in pregnant women were reported to the CDC; all were in women who had developed pneumonia and subsequent acute respiratory distress syndrome requiring mechanical ventilation.
Pregnant women might be at increased risk for complications from pandemic H1N1 virus infection. These data lend support to the present recommendation to promptly treat pregnant women with H1N1 influenza virus infection with anti-influenza drugs.
Vaccine experts who advise the U.S. government are likely on Wednesday to put healthcare workers, pregnant women and patients with asthma and diabetes at the front of the line to get vaccinated against the new pandemic H1N1 influenza.
◎U.S. panel to set priorities for H1N1 flu vaccines
ロイター Tue Jul 28, 2009