Nandost Kenari S, Haghshenas M, Mirzaei M, Rezaee M S, Tabrizi A. Prevalence of Influenza A Viruses in Patients with Flu Symptoms Attending Mazandaran Provinces Health Centers, 2009-2013. J Mazandaran Univ Med Sci 2014; 24 (119) :1-10
URL:
http://jmums.mazums.ac.ir/article-1-4512-en.html
Abstract: (11249 Views)
Background and purpose: Influenza A is an infectious disease caused by RNA viruses of the
influenza viruses. Influenza viruses spread around the world in seasonal epidemics. It is estimated to
affect %5-%15 of the global population and causing about 250000 to 500000 yearly deaths, rising to
millions in some pandemic years. The aim of this study was an epidemiological survey of influenza A
virus in patients from Mazandaran province, in North of Iran during 2009-2013 using Real Time
Polymerase Chain Reaction (RT-PCR).
Materials and methods: In this cross-sectional study, 2781 throat swabs from common cold
samples were collected from patients attending Mazandaran province health centers. Influenza-RNA was
extracted from samples using Pure LinkTM Viral RNA/DNA Kit. Identification of Influenza A viruses
was done through RT-PCR using Super Script III Platinum, and Quantitative Real Time PCR System
from Invitrogen with specific primers and probs. All samples were examined in the Influenza Laboratory
affiliated with Mazandaran University of Medical Sciences.
Results: A total of 2781 patients including 1543 (%55.48) female and 1238 (%44.52) male were
studied. We found 516 (%18.55) patients with influenza A virus of whom 281 (%55.46) were female and
235 (%45.54) were male. Most of these patients aged 21-30 years of old (%24.16). Influenza A virus was
observed more (%31.61) in 2012.
Conclusion: Influenza is one of the most prominent respiratory infections of human which
causes severe morbidity and mortality. New influenza A viruses are constantly evolving by mutation or
by re-assortment, since the influenza virus evolves rapidly, and new strains quickly replace the older
ones. Due to the high mutation rate of the virus, a particular influenza vaccine usually confers protection
for no more than few years. Identification of different types of viruses could be of great benefit in
developing efficient vaccine.