Listeria  monocytogenes  

Tom  Duszynski,  MPH,  REHS  Director  of  Surveillance  and  

Inves>ga>on      

References  

•  Scallan,  E.,  Hoekstra  R.M.,  Angulo  F.J.,  Tauxe  R.V.,  Widdowson  M.A.,  Roy  S.L.,  et  al.  Foodborne  illness  acquired  in  the  United  States-­‐-­‐-­‐major  pathogens.  Emerg  Infect  Dis  2011;  17(1):  7-­‐15.    

•  Retrieved  from  hYp://www.cdc.gov/listeria/defini>on.html    on  December  27,  2011  

•  Retrieved  from  hYp://www.cdc.gov/listeria/outbreaks/cantaloupes-­‐jensen-­‐farms/index.html    on  December  27,  2011  

Listeria  monocytogenes  

•  Bacterium  Listeria  monocytogenes,  is  an  important  public  health  problem  in  the  United  States.    

•  The  disease  primarily  affects  older  adults,  pregnant  women,  newborns,  and  adults  with  weakened  immune  systems.    

•  Rarely,  persons  without  these  risk  factors  can  also  be  affected.    

Listeria  monocytogenes  •  Listeria  monocytogenes,  a  gram-­‐posi>ve            rod-­‐shaped  bacterium,  commonly                                          found  in  soil  and  water.    

•  Animals  can  carry  the  bacterium                                  without  appearing  ill  and  can  contaminate  foods  of  animal  origin,  such  as  meats  and  dairy  products.    

•  Most  human  infec>ons  follow  consump>on  of  contaminated  food.  Rare  cases  of  nosocomial  transmission  have  been  reported.  

Where  it  can  be  found  •  The  bacterium  has  been  found  in  a  variety  of  raw  foods,  such  as  uncooked  meats  and  vegetables  

•  Foods  that  become  contaminated  a^er  cooking  or  processing,  such  as  so^  cheeses,  processed  meats  such  as  hot  dogs  and  deli  meat  (both  products  in  factory-­‐sealed  packages  and  products  sold  at  deli  counters),  and  smoked  seafood.    

Where  it  can  be  found  •  Unpasteurized  (raw)  milk  and  cheeses  and  other  foods  made  from  unpasteurized  milk  are  par>cularly  likely  to  contain  the  bacterium.  

•  Listeria  is  killed  by  pasteuriza>on  and  cooking;  however,  in  some  ready-­‐to-­‐eat  foods,  such  as  hot  dogs  and  deli  meats,  contamina>on  may  occur  a^er  factory  cooking  but  before  packaging.    

•  Unlike  most  bacteria,  Listeria  can  grow  and  mul>ply  in  some  foods  in  the  refrigerator.  

 

Who  Gets  Listeriosis?  •  Pregnant  women  are  about  20  >mes  more  likely  than  other  healthy  adults  to  get  listeriosis.  About  one  in  six  (17%)  cases  of  listeriosis  occurs  during  pregnancy.  

•  Newborn  babies  suffer  the  most  serious  effects  of  infec>on  in  pregnancy.    

•  Persons  with  weakened  immune  systems  from  transplants  or  certain  diseases,  therapies,  or  medica>ons.  

Who  Gets  Listeriosis?  •  Persons  with  cancer,  diabetes,  alcoholism,  liver  or  kidney  disease.  

•  Persons  with  AIDS  are  almost  300  >mes  more  likely  to  get  listeriosis  than  people  with  normal  immune  systems.  

•  Older  adults  •  Healthy  children  and  adults  occasionally  get  infected  with  Listeria,  but  they  rarely  become  seriously  ill.  

Patients with non-pregnancy-associated listeriosis, by age group and sex, Listeria Initiative, 2009 (n=421).

Challenges  of  recogni>on  

•  Incuba>on  Period  for  Listerosis  is  3-­‐70  days  with  a  median  incuba>on  of  3  weeks  

•  Signs  and  Symptoms  mimic  many  other  infec>ons    

•  The  bacteria  can  stay  in  the  body  a  long  >me  before  making  a  person  sick,  allowing  more  people  to  be  infected  

Signs  and  Symptoms    

•  A  person  with  listeriosis  usually  has  fever  and  muscle  aches,  some>mes  preceded  by  diarrhea  or  other  gastrointes>nal  symptoms.  

•   Almost  everyone  who  is  diagnosed  with  listeriosis  has  "invasive"  infec>on,  in  which  the  bacteria  spread  beyond  the  gastrointes>nal  tract.  The  symptoms  vary  with  the  infected  person  

Signs  and  Symptoms  

•  Symptoms,  in  addi>on  to  fever  and  muscle  aches,  can  include  headache,  s>ff  neck,  confusion,  loss  of  balance,  and  convulsions.  

•  Pregnant  women  typically  experience  only  a  mild,  flu-­‐like  illness.  Infec>ons  can  lead  to  miscarriage,  s>llbirth,  premature  delivery,  or  life-­‐threatening  infec>on  of  the  newborn.  

Surveillance  •  Listeriosis  (infec>on  with  Listeria  monocytogenes)  was  added  to  the  list  of  na>onally  no>fiable  diseases  in  2001.  

•  To  improve  surveillance,  the  Council  of  State  and  Territorial  Epidemiologists  has  recommended  that  all  L.  monocytogenes  isolates  be  forwarded  to  state  public  health  laboratories  for  subtyping  

Sta>s>cs  •  Listeria  monocytogenes  is  es>mated  to  cause  nearly  1,600  illnesses  (Listeriosis)  each  year  in  the  United  States,  with  more  than  1,400  hospitaliza>ons  and  250  deaths    

•  Compared  to  1996-­‐1998,  the  incidence  of  listeriosis  had  declined  by  about  38%  by  2003.  

Sta>s>cs  

•   On  average  from  1998-­‐2008,  2.4  outbreaks  per  year  were  reported  to  CDC.    

•  Before  2011,  the  largest  outbreak  occurred  in  2002,  when  54  illnesses,  8  deaths,  and  3  fetal  deaths  in  9  states  were  found  to  be  associated  with  consump>on  of  contaminated  turkey  deli  meat.  

How  do  I  know  if  I  have  Listeriosis?  •  If  you  develop  fever  and  chills  while  pregnant  or  if  you  are  very  sick  with  fever  and  muscle  aches  or  s>ff  neck,  consult  your  doctor  immediately.    

•  A  blood  or  spinal  fluid  test  (to  look  for  the  bacteria)  will  show  if  you  have  listeriosis.  

Diagnosis  &  Tes>ng  

•  Diagnosis  is  confirmed  only  a^er  isola>on  of  Listeria  monocytogenes  from  a  normally  sterile  site,  such  as  blood,  or  from  amnio>c  fluid  or  the  placenta  in  the  semng  of  pregnancy.    

Treatment  &  Outcomes    

•  Listeriosis  is  treated  with  an>bio>cs.  A  person  in  a  high-­‐risk  category  who  experiences  flu-­‐like  symptoms  within  2  months  of  ea>ng  contaminated  food  should  seek  medical  care  

•  Even  with  prompt  treatment,  some  listeriosis  cases  result  in  death.  This  is  par>cularly  likely  in  older  adults  and  in  persons  with  other  serious  medical  problems.  

The  2011  Outbreak    

Listerosis  and  Cantaloupes    •  In  2011,  cantaloupes  contaminated  with  the  bacteria  Listeria  monocytogenes  caused  the  deadliest  foodborne  disease  outbreak  in  the  United  States  in  nearly  90  years.    

Outbreak  Inves>ga>on    

•  September  2  –  Listeria  'spike'  reported  in  Colorado  

•  Local  doctors  report  seven  cases  of  listeria  infec>on  far  more  than  usual  

•  Outbreak  defini>on:  More  cases  of  disease  than  expected  in  a  given  popula>on  at  a  given  >me    

Outbreak  Inves>ga>on    

•  September  2:  The  Colorado  Department  of  Public  Health  and  Environment  (CDPHE)  no>fies  the  Centers  for  Disease  Control  and  Preven>on  (CDC)  of  seven  ill  persons  with  listeriosis  (Listeria  infec>on)  reported  since  8/29/11.    

•  September  5:  Cantaloupes  are  collected  by  CDPHE  for  Listeria  tes>ng  from  the  home  of  an  ill  person.    

Outbreak  Inves>ga>on  •  September  6th    PulseNet  defines  the  Outbreak  strain      Cases  seen  in  the  NE  and  Texas  with  the  strain  

Outbreak  Inves>ga>on  

•  September  7th-­‐-­‐    CDC  begins  coordina>on  of  a  mul>-­‐state  inves>ga>on    

•  September  8th—States  with  cases  are  asked  to  use  supplemental  ques>onnaire  to  learn  more  about  possible  exposure  

•  September  9th–  Cantaloupes  are  iden>fied  as  a  likely  suspect  in  the  outbreak.    

Outbreak  Inves>ga>on    

•  September  10:  FDA  and  CDPHE  visit  Jensen  Farms  for  an  inspec>on  and  to  collect  environmental  and  product  samples.  The  broker  for  Jensen  Farms  stops  distribu>on  of  cantaloupes  and  tells  grocery  stores  to  remove  Jensen  Farms  cantaloupes  from  shelves.  

•  September  11th  –  Preliminary  Traceback  suggests  cantaloupes  were  produced  at  Jensen  Farms  

Outbreak  Inves>ga>on  

•  September  12th–  CDC  post  mul>state  outbreak  informa>on  of  Listeriosis  linked  to  cantaloupes  and  issues  na>onal  listeria  warning,  saving  many  lives  

•  September  13th  –  FDA  issues  a  statement  that  most  ill  people  consumed  cantaloupes  

•  September  14th  –  CDC  posts  a  web  update  linking  the  listerosis  cases  to  cantaloupes  produced  at  Jensen  Farms.    

Outbreak  Inves>ga>on    

•  September  22:  FDA,  along  with  CO  state  and  local  officials,  begins  an  environmental  assessment  at  Jensen  Farms.    

•  September  23:  Carol’s  Cuts  of  Kansas  City,  Kansas  ini>ates  a  recall  of  cantaloupe  

•  October  6:  Fruit  Fresh  Up  of  Buffalo,  New  York  ini>ates  a  recall  of  individual  packages  of  fresh  cut  cantaloupe  

Outbreak  Inves>ga>on    

•  October  18:  FDA  issues  a  warning  leYer  to  Jensen  Farms  based  on  the  presence  of  the  outbreak  strains  of  Listeria  in  environmental  and  cantaloupe  samples  taken  on  9/10.  

•  October  19:  FDA  announces  findings  of  its  environmental  assessment  at  Jensen  Farms  

Outbreak  Inves>ga>on  •  146  cases,  30  deaths,  and  1  miscarriage  in  28  states.    

•  Onset  ranged  from  July  31,  2011  through  October  27,  2011.  

•   Ages  ranged  from  <1  to  96  years,  median  age  of  77  years.    

•  Most  ill  persons  were  over  60  years  old.  58%  of  ill  persons  were  female.    

•  Among  the  144  ill  persons  142  (99%)  were  hospitalized.    

Outbreak  Inves>ga>on    

•  Collabora>ve  inves>ga>ons  by  local,  state,  and  federal  public  health  and  regulatory  agencies  indicated  that  the  source  of  the  outbreak  was  whole  cantaloupe  grown  at  Jensen  Farms’  

•  Among  the  140  ill  persons  with  available  informa>on  on  what  they  ate,  131  (94%)  reported  consuming  cantaloupe  in  the  month  before  illness  onset.    

Outbreak  and  Lab  Tes>ng    

•  Laboratory  tes>ng  by  the  Colorado  Department  of  Public  Health  and  Environment  iden>fied  Listeria  monocytogenes  outbreak  strains  on  cantaloupes  collected  from  grocery  stores  and  from  ill  persons'  homes.    

•  Product  traceback  informa>on  from  Colorado  state  officials  indicated  that  these  cantaloupes  also  came  from  Jensen  Farms.    

Ques>ons  •  Wash  your  hands  •  Stay  home  if  you’re  sick  •  Get  your  vaccines  

•  Tom  Duszynski,  tduszyns@isdh.in.gov                                        317-­‐233-­‐7009