Three influenza pandemics have occurred in the 20th century. The “Spanish” flu of 1918-19 killed over 40 million people worldwide. Some virologists refer to this as “Swine” flu. The population of young healthy adults was particularly affected: one of every 100 persons aged 20-39 years died of influenza-related causes. Some historians believe that World War I ended in part because of this pandemic. The “Asian” flu occurred with the transmission into humans of the avian influenza virus type A (H2N2), causing over 1 million deaths in 1957-58 worldwide. The H2N2 virus no longer circulates in humans. The most recent pandemic was the “Hong Kong” flu (H3N2) which occurred in 1968-69 and killed approximately 1 million people worldwide. The 1976 pandemic originated in China and spread round the globe in under a year. Infection was mainly limited to young persons because many older people had antibodies acquired from childhood infection with related strains. Slide 9
First case linked to second wave of SARS was 96 yo on an ortho ward – admitted March 22 – onset of illness April 2 Link through patient transfer to rehab hospital 67/74 cases of SARS from april 15 to June 9 resulted directly from exposure in the index hospital
Two phases of the outbreak in Taiwan: March 7 to April 18 and after April20. First phase was travel related – first recogized case was a 54 yo businessman who returned from guangdong province by way of hong kong – he became symptomatic Feb 25 About 80% of cases in first wave were travel related. In second wave – 90% cases were hospital acquired Index hospital, spread was related to a laundry worker – seen in the ER from april 12, 14, 15 - interacted with staff, other patients, and vistors – off duty would socialize in the ED – diarrhea, fever, then respitatory symptoms – intubated April 22. -
Green dots on this slide represent the locations of WNV infected mosquito pools, the majority of which were culex species. Although no human cases were documented in NJ, positive mosquitoes pools were identified. Northern Queens had the highest concentration of infected mosquitoes.
EMERGING INFECTIOUS DISEASES Mark Loeb, MD, MSc, FRCPC
A/Fujian/411/2002 (H3N2) Neuraminidase Hemagglutinin Type of nuclear material Virus type Geographic origin Strain number Year of isolation Virus subtype
Cellular Pathogenesis Flint et al . Principles of Virology: Molecular Biology, Pathogenesis, and Control .
Natural History of Clinical Influenza Runny Nose Sore Throat Myalgia Headache Cough Anorexia Malaise Symptoms: 0 1 2 3 4 5 6 7 8 Days after Onset 38.5 37.5 36.5 Oral Temperature 0 C Onset of Illness
March 25, 2003 March 29, 2003 April 2, 2003 Severe Acute Respiratory Syndrome (SARS)
Spread from Hotel “M” March 2003 Hotel M Hong Kong Guangdong Province Hong Kong 95 HCW A A H, J Vietnam 37 HCW B C, D,E Singapore 34 HCW US I, L,M K Ireland F, G Canada 18 HCW
Probable and Suspect Cases of SARS in Ontario by Date of Onset Probable Suspect Date of Onset 2-Mr 9-Mar 23-Mar 30-Mar 13-Apr 20-Apr 4-May 11-May 25-May 18-May 6-Apr 16-Mar 23-Feb 1-Jun 8-Jun 15-Jun 22-Jun 30-Jun