title: Avian influenza virus in pregnancy.
abstract: The unprecedented epizootic of avian influenza viruses, such as H5N1, H5N6, H7N1 and H10N8, has continued to cause disease in humans in recent years. In 2013, another novel influenza A (H7N9) virus emerged in China, and 30% of those patients died. Pregnant women are particularly susceptible to avian influenza and are more likely to develop severe complications and to die, especially when infection occurs in the middle and late trimesters. Viremia is believed to occur infrequently, and thus vertical transmission induced by avian influenza appears to be rare. However, avian influenza increases the risk of adverse pregnancy outcomes, including spontaneous abortion, preterm birth and fatal distress. This review summarises 39 cases of pregnant women and their fetuses from different countries dating back to 1997, including 11, 15 and 13 infections with H7N9, H5N1 and the 2009 pandemic influenza (H1N1), respectively. We analysed the epidemic features, following the geographical, population and pregnancy trimester distributions; underlying diseases; exposure history; medical timelines; human-to-human transmission; pathogenicity and vertical transmission; antivirus treatments; maternal severity and mortality and pregnancy outcome. The common experiences reported in different countries and areas suggest that early identification and treatment are imperative. In the future, vigilant virologic and epidemiologic surveillance systems should be developed to monitor avian influenza viruses during pregnancy. Furthermore, extensive study on the immune mechanisms should be conducted, as this will guide safe, rational immunomodulatory treatment among this high-risk population. Most importantly, we should develop a universal avian influenza virus vaccine to prevent outbreaks of the different subtypes. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Infectious Diseases, Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang Province, China.
authors.forename: Shelan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Endocrinology, The 421 Hospital of Chinese People's Liberation Army, Guangzhou, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Sha
authors.affiliation: Department of Infectious Diseases, Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang Province, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Endocrinology, The 421 Hospital of Chinese People's Liberation Army, Guangzhou, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Centre for Geographic Information Science, Research Centre for Humanities and Social Science, Academia Sinica, Taipei, Taiwan.
authors.forename: Ta-Chien
authors.initials: TC
authors.lastname: Chan
authors.affiliation: Department of Infectious Diseases, Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang Province, China.
authors.forename: Xiaoxiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Pan
authors.affiliation: Department of Infectious Diseases, Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.affiliation: Department of Infectious Diseases, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China.
authors.forename: Shenghua
authors.initials: S
authors.lastname: Mao
authors.affiliation: Department of Reproductive Endocrinology, Key Laboratory of Reproductive Genetics, Ministry of Education, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Run Ju
authors.initials: RJ
authors.lastname: Zhang
authors.affiliation: Department of Infectious Diseases, Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang Province, China.
authors.forename: Enfu
authors.initials: E
authors.lastname: Chen
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use; D002681:China; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D018445:Infectious Disease Transmission, Vertical; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D053124:Influenza A Virus, H5N1 Subtype / Q000302:isolation & purification*; D064766:Influenza A Virus, H7N9 Subtype / Q000302:isolation & purification*; D007252:Influenza Vaccines / Q000276:immunology / Q000302:isolation & purification; D007251:Influenza, Human / Q000188:drug therapy / Q000473:pathology* / Q000517:prevention & control / Q000821:virology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy / Q000473:pathology* / Q000517:prevention & control / Q000821:virology*; D055502:Secondary Prevention; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D007155:Immunologic Factors; D007252:Influenza Vaccines