Since the spring of 1977, two subtypes of influenza A virus (H3N2 and H1N1) have been seasonally infecting the human population. In this work we study the distribution of patient ages within the populations that exhibit the symptomatic disease caused by each of the different subtypes of seasonal influenza viruses. When the publicly available extensive information is pooled across multiple geogr...

Swine influenza (SI) is a respiratory disease of pigs caused by type A influenza that regularly causes pandemics. SI viruses do not normally infect humans; however, human infections with SI do occur, and cases of human-to-human spread of swine flu viruses have been documented. Swine influenza also called as swine flu, hog flu, and pig flu that refers to influenza is caused by those strains of i...

In the rainy season of 1989, 72 strains of influenza viruses were isolated in Thailand by using MDCK cell cultures, which included 36 samples belonging to H1N1, 24 samples belonging to H3N2 subtype of type A and 12 samples of type B1). The identified viruses were inoculated into developing hen's eggs of 10 days' age, and 22 (32.6%) of them were adapted to the egg after one passage, which includ...

Despite a mass of research on the epidemiology of seasonal influenza, overall patterns of infection have not been fully described on broad geographic scales and for specific types and subtypes of the influenza virus. Here we provide a descriptive analysis of laboratory-confirmed influenza surveillance data by type and subtype (A/H3N2, A/H1N1, and B) for 19 temperate countries in the Northern an...

BACKGROUND Pregnant women were at increased risk for serious outcomes of 2009 pandemic influenza A virus subtype H1N1 (influenza A[H1N1]pdm09) infection, but little is known about the overall impact of the pandemic on neonatal and maternal outcomes. METHODS We identified live births that occurred from 1 July 2008 through 31 May 2010 in 5 Kaiser Permanente regions. Pregnant women were consider...

Influenza surveillance was carried out in a subset of patients with influenza-like illness (ILI) presenting at an Employee Health Clinic (EHS) at All India Institute of Medical Sciences (AIIMS), New Delhi (urban) and pediatric out patients department of civil hospital at Ballabhgarh (peri-urban), under the Comprehensive Rural Health Services Project (CRHSP) of AIIMS, in Delhi region from Januar...