**Preface XI**


Nikolaevna Stolpnikova, Alexander Petrovich Cherdantsev and Anna Egorovna Vlasenko

Preface

Influenza is a perpetual economic burden causing significant morbidity and mortality rate in humans. Globally, the reported cases of seasonal influenza viruses rise up to 3–5 million during epidemics with estimated death toll of 290,000–650,000 per year. Comorbidity condi‐ tion (such as diabetes and heart or liver disease) and immunocompromised condition of the patients are predominant causes of mortality associated with influenza virus. Transmission of influenza virus occurs by direct or indirect contact, inhaling virus-infected droplets or the small droplet nuclei, exposure to diseased poultry, intake of raw or undercooked poultry, or transplacental transmission. Influenza viruses enter humans through the respiratory tract by oral or nasal route, and then they cross the mucous layer surrounding the respiratory epi‐ thelium. The host defense mechanism gets activated to prohibit the spread of the virus. In‐ nate and adaptive immune responses collectively play an important role in clearance of influenza virus from the host. A comprehensive understanding at the molecular and genetic level of the avian and swine influenza virus will strengthen us in understanding their mech‐ anism of reassortment and transmission in humans. Several antivirals are given for the treat‐ ment of influenza virus infection such as adamantanes, oseltamivir, and zanamivir targeted toward viral proteins. The complementary and alternative medicine provides an additional support to the antivirals for its treatment. The development of the vaccine should consider several strategies such as epidemiological data of the previous pandemic influenza viruses, presence of viruses in nature, and viruses responsible for infecting human population. The current influenza vaccines available are live attenuated influenza vaccines (LAIV), inactivat‐ ed influenza vaccine (IIV), recombinant subunit DNA, and vectored virus vaccine. There are some limitations associated with influenza virus vaccines suggesting circulating virus, and the vaccine virus should be of same strains to give a high efficacy, or else the vaccine might provide a false sense of security. Other preventive methods to control influenza are proper hand washing, the use of masks, covering the mouth during coughing and sneezing, avoid‐ ing physical contacts with influenza-infected individuals, wearing gloves while working with infected poultry or swine, and intake of effective antiviral medications. Awareness re‐

garding the prevention and control methods of influenza should be widely spread.

man race from more loss of resources and economies due to pathogens.

This book covers a collection of articles by brilliant researchers who have devoted their time to combat influenza. This book gives a comprehensive overview of recent advances in influ‐ enza, as well as general concepts of molecular biology of influenza infections, epidemiology, immunopathology, prevention, and current clinical recommendations in management of in‐ fluenza, including preparation of vaccines, assessment of the safety and quality of influenza vaccines and adjuvants highlighting the ongoing issues and recent advances, with future directions in prevention and therapeutic strategies. The book focuses on various aspects and properties of influenza, whose deep understanding is very important for safeguarding hu‐

