 A worldwide epidemic of a disease  Epidemic = increased number of cases from a disease  Pandemics have occurred from › Bacteria – cholera, Tuberculosis, Typhus, Bubonic plague › Viruses – smallpox, influenza

 The smallest of the microbes  Contain genetic material ( DNA or RNA or both )  Nuclear material contained within a capsid  Parasitic, hijack host cell and replicate

 New strains of virus  Take advantage when herd immunity is low  Transmissible  Limited treatment options  Influenza takes advantage of all of these to cause pandemics

 Virus first described by Hippocrates in 412 BC  Influenza pandemics occur every years  RNA virus

 Disease characterized by fever, headache, malaise, myalgias  Respiratory symptoms include sore throat, cough, nasal congestion  May include GI symptoms  Onset 3-6d after exposure  Symptoms last 4-7 days

results from RNA mutations changes surface proteins so they are not recognized by existing antibodies

Can occur in 3 ways A)Genetic mixing in an intermediate host B)Direct transmission to a new host C)Direct transmission to an intermediate host and then on to humans

 First reported in Russia May1889  Hit North America by December 1889  By February 1890 it had travelled to South America  Later reaching India and Australia  High mortality rate  Estimated one million deaths

 Started in the fall of 1918 and rapidly spread across the globe  Killed million people by end of 1919  Mortality approximately 2-3%  Most deadly for year olds  Avian H1N1

 Feb. 1957, new influenza identified in the far east, H2N2  Vaccine available Aug  Milder illness than Spanish flu ( % mortality)  Most disease in children and young adults  Most deaths Sept 1957-Mar 1958  Estimated 2 million deaths worldwide

 1968/9 pandemic 2 peaks  Milder disease, H3N2  Vaccine available in US one month after first cases identified  Estimated one million deaths worldwide  Mortality rate 0.1%

 Jan 1976 respiratory outbreak Fort Dix  Identified as swine H1N1 influenza  Fear that this virus may case pandemic as H1 and N1 had not circulated in humans in 50 years  In the end 13 ill, 1 dead, 500 others exposed  Did not spread beyond Fort Dix

 Began in China in May 1977, identified in Russia in Nov.  Affected those < 23yo  Disease mild and mortality low  Mortality = seasonal influenza  H1N1 virus

 Another pandemic was imminent  Lots of work done in Pandemic planning  Identify a team of “experts”  Plan for high absentee rates (10-50%)  Protect staff in the workplace  Communication and knowledge management

 Identify a team of “experts”  Plan for high absentee rates (10-50%)  Protect staff in the workplace  Communication and knowledge management

 H1N1 virus has previously been identified in humans  New strain with genetic elements from North American and European swine influenza, North American avian influenza and human influenza  Never previously seen in humans

 Initial cases identified in Mexico  Initial reports showed high mortality  WHO began actively tracking cases  Once virus identified, track of spread

 Phase 1 – no animal influenza known to be circulating in humans  Phase 2 – a circulating animal influenza known to infect human posses a threat  Phase 3 – animal or human-animal virus has caused sporadic disease but no human-human transmission sufficient to cause pandemic Prepare pandemic plans, surveillance systems, communication systems and plan to scale up as needed

 Phase 4 – human-human transmission of animal or animal-human virus able to sustain community level outbreak Implement containment protocols to prevent spread, increase surveillance, communicate protection plan to population and activate contingency plans

 Phase 5 – virus as in phase 4 causes sustained community outbreaks in 2 or more countries in one WHO region Pandemic – implement pandemic plans, active surveillance and monitoring, update public health and other stakeholders on ways to mitigate risk WHO declared phase 5 on April 29, 2009

 Phase 6 – same criteria as phase 5 with spread to one other WHO region WHO declared phase 6 in June 2009

 April 12, 2009-March 27, 2010  1,843 hospitalizations  319 ICU admissions  128 death  March ,759 lab confirmed cases of H1N1 PHAC FluWatch , Ontario Influenza Bulletin

 April 12, 2009-March 27, 2010  8,677 hospitalizations  1,473 ICU admissions  428 deaths  Hospitalization rate 25: , death rate 1.3: (0.0013%)  Only 13 hospitalizations and 2 deaths since 2010 PHAC FluWatch

 9 April As of 4 April 2010, worldwide more than 213 countries and overseas territories or communities have reported laboratory confirmed cases of pandemic influenza H1N1 2009, including over deaths. WHO  Most activity in Southeast Asia, West Africa  Mortality rate %

 Access to supplies  Access to reliable information  Communication within organizations

 Arepanrix (adjuvanted)  Contains split, inactivated influenza virus  Single dose of vaccine is effective  AE – pain, redness, swelling at inject. Site, myalgias and fatigue  Jan30/10 – million doses administered  6,131 AE (24.4/100,000) – 250 “serious” (0.99/100,000)– of these 131 anaphylaxis (0.52/100,000 ) – all within acceptable range for vaccines

 Vaccine supply chain in Canada › Vaccine comes from supplier to government › Supply is reviewed › Customer service determines distribution › Vaccine is repackaged › Shipments prepared in warehouse › Vaccine delivered to PH units › Vaccine delivered to public Health Canada

 Federal government purchased 50.4 million doses if vaccine for distribution to provinces and territories  Excess vaccine estimated at million doses  Many reasons for this  Initial estimates were that 25% of population received H1N1 vaccine  37% US HCP received the H1N1 vaccine

 4 Canadian studies  Monitoring of flu found those who had seasonal flu vaccine were 68% more likely to get H1N1 infection  Case control studies in Canada and Quebec and transmission study in Quebec showed risk increased by 1.4-5X PLoS Medicine, April 6, 2010

 Antivirals – recommended for age < 1, severe illness, immunocompromised, pregnant  Should be started within 48hr of symptom onset  Oseltamavir (Tamiflu) – oral  Zanamivir (Relenza) - inhaled