Foodborne Disease and Vulnerable Groups

Posted by Adaora Anozie

On March 4, 2015
Foodborne  disease  may  be  caused  by  pathogenic  microorganisms  or  by  toxic  chemicals.    For  microbial
hazards,  susceptibility  may  be  increased  by  many  factors,  particularly  those  that  reduce  immune  system
function.    For  example,  neonates,  infants,  young  children  are  more  vulnerable  to  certain  foodborne
diseases  because  of  immaturity  of  their  immune  and  physiologic  systems.    For  the  elderly,  progressive
weaknesses  of  the  immune  system  play  a  major  role.    Another  group  is  pregnant  women  because  of
immune  tolerance  to  the  fetus.    Also  vulnerable  are  those  having  poor  nutritional  status,  existing  health
problems,   such   as   HIV   infection   and   liver   disease,   and   drug   therapies   which   suppress   the   immune
system,  such  as  those  for  cancer    and  organ  transplantation.  Such  persons  are  not  only  more  likely  to
acquire  foodborne  infections,  but  also  are  prone  to  more  severe  disease  outcomes,  including  higher
mortality   rates.     The   main   pathogens   involved   include   bacteria   (Salmonella,   Escherichia   coli,  Campylobacter,   Listeria   monocytogenes)   and   viruses   (norovirus,   rotavirus),   as   well   as   parasites
(Cryptosporidium,  Giardia,  Toxoplasma  gondii).
For  chemical  intoxications,  windows  of  vulnerabilities  may  occur  at  different  stages  of  life  and  can  result
in  both  acute  and  chronic  health  effects.    Chemical  exposures  of  the  fetus  can  lead  to  spontaneous ,abortion,  low  birth  weight,  structural  congenital  abnormalities  and  carcinogenesis.    The  fetus  and  the
young  are  also  vulnerable  to  chemically induced  mental  and  physical  developmental  deficits,  such  as
reduced  intelligence  caused  by  exposure  to  lead.    Because  children  consume  twice  to  three  times  the
amount  of  food  on  a  body  weight  basis  compared  to  an  average  adult,  children  are  generally  more
vulnerable   because   of   their   increased   exposure   to   toxic   chemicals.     In   the   case   of   food   allergies,
vulnerability   is   due   to   an   overly   active   immune   system   in   contrast   to   biological   hazards   where   the
immune   system   is   impaired.     Allergies   due   to   food   proteins   are   not   uncommon   with   the   most
predominant  being  allergies  to  milk,  eggs,  peanuts,  tree  nuts,  fish,  shellfish,  soy,  and  wheat  and  where
reactions  can  be  mild  to  life threatening.    While  the  number  of  people  allergic  to  a  specific  food  may  be
low,  the  total  number  of  people  with  food  allergies  is  sizable.    Another  vulnerable  group  is  those  who
are  deficient  in  a  key  enzyme  that  inhibits  their  metabolism  of  certain  food  components,  such  as  lactose.