Health officials today reiterated that the novel H1N1 virus continues to spread rapidly around temperate zones of the Northern Hemisphere, hospitalizing and killing an unusual number of children, young adults, and pregnant women. The need for vaccine and antivirals remains pressing in these countries, and demand currently outstrips supply. Confusion also still complicates efforts to treat and prevent disease.Between 1% and 10% of people who develop swine flu require hospitalization, according to a review of the current epidemiologic data released today by the World Health Organization (WHO). The new data were discussed 27-29 October at a meeting of WHO’s Strategic Advisory Group of Experts (SAGE) on Immunization. Up to 25% of hospitalized people are admitted to intensive care units, and between 2% and 9% die. Pregnant women make up 7% to 10% of hospitalized patients.In a departure from official recommendations made elsewhere, SAGE announced that people regardless of age need only one dose of the H1N1 vaccine. The U.S. Centers for Disease Control and Prevention (CDC) recommends that children under 10 receive two doses. After the European Medicines Agency’s Committee for Medicinal Products for Human Use meeting 19-22 October, the agency recommended that everyone regardless of age receive two doses of the pandemic flu vaccines approved for use there. Granted, different vaccines are in use in different locales, but the differences reflect that data from clinical trials of various vaccines in a range of age brackets is still preliminary. And the dosing questions impact both the efficacy of the vaccines and their availability, given that they remain in short supply everywhere.Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)At a press conference held today by the CDC, its director, Tom Frieden, addressed the discrepancies about children under age 10. CDC based its decision for children under 10 to receive two doses on preliminary data from clinical trials of the vaccines being used in the United States, but he said more complete data should emerge soon. “Throughout this entire response, our approach is, look at the data and follow the data,” said Frieden. Frieden also revealed new data about deaths in children. To date, 119 children with confirmed infection of the novel H1N1 virus have died from the disease in the United States. That is 19 more than 1 week earlier, the largest jump yet seen in a single week. The virus also is now widespread in all but two states, the most activity yet reported. Although spread has started to decrease in a few locales, Frieden stressed that “we don’t know whether that’s a decrease before an additional wave.”As of today, CDC has 26.6 million doses of H1N1 vaccine available, and Frieden emphasized that this is 10.5 million more than they had 1 week ago. CDC is also racing to keep up with demands for pediatric formulations of the anti-influenza drug Tamiflu. It has now released its entire stockpile of liquid Tamiflu, which amounts to 534,000 courses of the drug. CDC is also encouraging pharmacists to make syrup for children from adult capsules of the drug. If parents can only obtain pediatric capsules of Tamiflu, CDC says they, too, can mix that with syrup at home.