Daffodil International University

Faculty of Allied Health Sciences => Disease Outbreak => Public Health => Avian influenza => Topic started by: 710001983 on August 25, 2018, 04:07:58 PM

Title: Avian infl uenza goes global, but don’t blame the birds
Post by: 710001983 on August 25, 2018, 04:07:58 PM
Since   early   2006,   highly   pathogenic   avian   influenza H5N1 has been clocking up air miles at an alarming rate. It  has  spread  quickly  to  Europe,  the  middle  east,  India,  and Africa following no apparent pattern, and underlining how  little  scientists  know  about  the  virus  ecology  and  where  it  will  strike  next.  There  is  now  growing  concern  that  the  whirlwind  spread  of  avian  flu  in  some  parts  of  the world is not entirely governed by nature, but by the human activities of commerce and trade. Since mid-2005, the Food and Agriculture Organisation  (FAO) and WHO have given wide prominence to the theory that  migratory  birds  are  carrying  the  H5N1  virus  and  infecting   poultry   flocks   in   areas   that   lie   along   their migratory  route.  Indeed,  this  is  probably  how  the  virus  reached  Europe.  Unusually  cold  weather  in  the  wetlands  near  the  Black  Sea,  where  the  disease  is  now  entrenched,  drove  migrating  birds,  notably  swans,  much  further  west  than usual. But despite extensive testing of wild birds for the disease, scientists have only rarely identified  live  birds  carrying  bird  flu  in  a  highly  pathogenic  form,  suggesting 
these    birds    are    not    efficient    vectors    of    the    virus. 

Furthermore,  the  geographic  spread  of  the  disease  does  not  correlate  with  migratory  routes  and  seasons.  The  pattern  of  outbreaks  follows  major  road  and  rail  routes,  not flyways.  Far more likely to be perpetuating the spread of the virus is the movement of poultry, poultry products, or infected material from poultry farms—eg, animal feed and manure. But  this  mode  of  transmission  has  been  down-played  by  international agencies, who admit that migratory birds are an easy target since nobody is to blame. However, GRAIN, an   international,   non-governmental   organisation   that   promotes   the   sustainable   management   and   use   of   agricultural biodiversity, recently launched a critical report titled Fowl  play:  the  poultry  industry’s  central  role  in  the  bird  flu  crisis.GRAIN points a finger  at  the  transnational  poultry  industry  as  fuelling  the  epidemic.  Over  the  years,  large 
concentrations    of    (presumably    stressed)    birds    have    facilitated an increased affinity of the virus to chickens and
other domestic poultry, with an increase in pathogenicity. Since the 1980s, the intensification of chicken production in  eastern  Asia  has  gained  momentum,  changing  the  whole dynamic of avian influenza  viruses  in  the  southern China epicentre, which has had far-reaching consequences for the rest of the world.

Source: https://www.thelancet.com/action/showPdf?pii=S1473-3099%2806%2970417-0
Title: Re: Avian influenza goes global, but don’t blame the birds
Post by: Dr Alauddin Chowdhury on November 12, 2018, 10:08:24 AM
Title: Re: Avian infl uenza goes global, but don’t blame the birds
Post by: tokiyeasir on November 12, 2018, 11:17:54 AM