Page 64 - Poultry-Punch April 2020 edition
P. 64

POULTRY PUNCH                                                                         ARTICLE
                         AVIAN CORONA





                                VIRAL DISEASES







                                                                                Prof. R.N.Sreenivas Gowda,
                                                  Poultry disease specialist and former VC,KVAFSU,Bidar.
                                                                                   drrns.gowda@gmail.com


                 he word  ‘Corona’ has become a street popular language, it   Both SARS- and MERS-CoVs crossed the species barrier from bats to
                 is so popular  that even the people in   remote areas of the   humans through civet cats and camels as intermediate organisms.
              Tvillages  speaks and make fun of it. Now everyone knows   The current Novel Coronavirus covid-19 is the other face of SARS
            about the difference between virus and bacteria and become so   and hence called SARSII baffling the entire world.
            familiar of these terms.  No surprise that the children born in this   Wild bird species serve as a natural reservoir of many emerging
            period  may named either COVID  for male and CORONA for female   zoonotic pathogens and thus have a significant impact on public
            child. Thanks to the news media and television media for their   health.  They  are  also  the  source  of  pathogens  dangerous  to
            observations    and  creating  awareness  of  this  pandemic  disease   domestic animals, and such infections could have socio-economic
            COVID-19.All the corona will not create serious infections, if  only   consequences.
            genetically modified or mutated to highly pathogenic strain then  it
            will cause infection. The role of this corona virus causing respiratory
            infection in human was detected only  in the year 1960.
              But, the corona virus is not new to our  poultry scientists. They
            are aware of corona virus as early as 1930’s. Since nine decades
            poultry scientists are working on various aspects of its existence,
            behavior, pathogenesis, molecular biology, vaccine manufacturing
            and  control  of  this    virus.So  far  there  is  no  history  of    causing
            infectious bronchitis in any scientist or the farmers working   in
            poultry.
              Coronaviruses  (CoVs)  are  a  large  group  of  enveloped  viruses
            with  a  single-strand  RNA  genome,  which  continuously  circulate
            in mammals and birds and pose a threat to livestock, companion
            animals,  and  humans.  CoVs    harboured    by  avian  species  are
            classified to the genera gamma- and delta corona viruses. Within
            the gamma-CoVs the main representative is avian coronavirus, a   Proposed epidemiology and transmission of IBV among wild
            taxonomic name which includes the highly contagious Infectious   birds and poultry (Adopted from Woo et al.,2009)
            bronchitis viruses (IBVs) in chickens and similar viruses infecting   Avian coronavirus  (IBV)  is  a  coronavirus  which  infects  birds,
            other domestic birds such as turkeys, guinea fowls, or quails.   causing the associated disease, infectious bronchitis (IB). It is a
              Similarly  to  other  RNA  viruses,  coronaviruses  (CoVs)  are   highly  infectious  avian  pathogen  which  affects  the  respiratory
            characterised  by  high  genetic  diversity  driven  by  mutation  and   tract, gut, kidney and reproductive systems of chickens.
            recombination, which can lead to the emergence of new viruses.   IBV affects the performance of both meat producing and egg
            Such new pathogens can have new features which even enable   producing chickens and is responsible for substantial economic loss
            them to switch to new hosts . These newly created viruses can   within the poultry industry.
            acquire  zoonotic  potential,  as  witnessed  by  the  Severe Acute
            Respiratory Syndrome (SARS), the epidemic from Southern China   Host Specificity
            in  2003  caused  by  SARS-CoVs.  This  disease,  termed  “atypical   The domestic fowl (Gallus gallus) and pheasant (Phasianus spp.)
            pneumonia”, was diagnosed in humans in 29 countries and had a   are  considered  to  be  natural  hosts  for  IBV  but,  other  IBV-like
            nearly 10% mortality rate. In 2012, there emerged a subsequent   coronaviruses have been identified in nondomestic avian species
            disease caused by a novel coronavirus, the so-called Middle East   including pheasant, peafowl, turkey, teal, geese, pigeon, penguins
            respiratory  syndrome  (MERS)  with  even  higher  mortality  rates.   quail,  duck,  and  Amazon  parrot.  Antigenic  similarities  between



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