New respiratory pathogens: influenza A/H7N9 and coronavirus MERS CoV

The group of human respiratory pathogens of viral origin is taxonomically diverse. Influenza A viruses and coronaviruses are frequent

types of newly emerging agents due to genome plasticity and zoonotic occurrence. The population of migrating waterfowl is the main

reservoir of influenza A virus. In the recent years, the incidence of infection with the H7 subtype has increased, and in March last year

the first human infection with a novel combination of the A(H7N 9) subtype was detected in China. The infection often manifested

with a severe course, including death. During the so-called first wave (March to May 2013), 137 diseases and 45 deaths were laboratory

confirmed; from October to 27 January (the second wave), 116 diseases were confirmed with a steep increase in January 2014, with the

data on death rates being inconsistent. Bats are likely to be the main reservoir of coronaviruses. The first case of disease with the novel

MERS CoV was described in June 2012 in the United Arab Emirates and two more cases of the disease were documented retrospectively.

The reservoir and source of this virus have not yet been identified unequivocally although the same virus was confirmed by direct and

indirect evidence in camels and dromedaries kept in the Middle East region. From April 2012 to 20 January 2014, a total of 178 human

cases were confirmed of which 76 ended fatally.

Keywords: respiratory viruses, influenza, H7N9, coronaviruses, MERS – CoV