Thread by @MackayIM

😷Lab-confirmed #Flu in #Australia to 21SEPT2019
⚪ pink line=positives for 2019, other colours=other years
🤧+3,143 over last *2* days
🤧283,742 cases for 2019

😷Lab-confirmed #Flu numbers
🤧Difference in totals, between reporting days, #Australia
🤧decline in positives slowly continues from mid-July peak
⚪ graph is a guide only. Each total may include NNDSS numbers that were added to previous as well as current days

😷 Rates and States, #Flu. New South Wales (NSW) remains the hottest spot overall
🤧 South Australia's (SA) early surge retains it the jurisdiction with the highest rate of cases per 100,000 population, but NSW closing in

😷 Flu in #Australia by age, sex & rate.
🤧 Very young have highest numbers *&* highest proportion testing positive
🤧 Older age groups aren't testing positive as often (cf to very young), but of those presenting with flu-like illness, a high proportion are #Flu positive

Source:www9.health.gov.au/cda/source/cda…

😷 #Flu activity in New South Wales (NSW) is high but ⬇
🤧respiratory presentations to EDs expected for this period & ⬇
🤧of those typed, mostly A (62%) and A/H3N2 the most common (79% of A)
🤧 38% FluB
🤧 235 (+19) lab-confirmed deaths
😷Source: health.nsw.gov.au/infectious/inf…

#Flu in Western Australia has basically returned to baseline.
Source: ww2.health.wa.gov.au/Reports-and-pu…

😷 #Flu in Tasmania remains at high levels but dropping; is below peak of 3 recent seasons - a *very* long season for them though
Source: dhhs.tas.gov.au/publichealth/c…

😷#Flu in Victoria has declined from last week (they don't do monthly graphs)
🤧 8 new residential aged care outbreaks in the past week (and previous years numbers tweaked)
Source: www2.health.vic.gov.au/about/publicat…

😷 #Influenza (#flu) thread for Australia's States and Territories
🤧 latest fortnightly national #flu report with data to 08SEPT2019
🤧 Source: www1.health.gov.au/internet/main/…
🤧 low clinical severity; low-moderate impact
🤧 national activity consistent with post-peak pattern & ⬇

🤧lab-confirmed activity still above 5-year average for same period but ⬇ this fortnight
🤧 2 of 4 sentinel labs report #flu as the most common cause of influenza-like illness (ILI), #RSV in 1/4, rhinovirus in 1/4
🤧 sentinel hospitalizations
⬇ in past fortnight (some backlog)

😷 lab-confirmed #flu cases still high &...
🤧 ⬇ in New South Wales, Queensland, Aust Capital Territory, Tasmania, Western Australia, Northern Territory
🤧↔️ in Victoria
🤧 ⬆️ in South Australia
😷 long legs on some of these concurrent epidemics we call
"flu season" in Aus

🤒 662 #flu associated deaths reported in Australia to date, up 72 from 590 a fortnight ago
⚪️ 643 due to FluA (28 A/H1N1 (+1..of those subtyped), 107 A/H3N2 (+4), 19 FluB (+3)
⚪️ median age of deaths 86 years (range <1-105 years)

🤒 overall, 66.4% ⬆ of detections were FluA across Australia, last fortnight
⚪️ 2.2% A/H3N2
⚪️ 0.1% A/H1N1
⚪️ Rest of FluAs not subtyped
⚪️ FluB (33.4% ⬆ from 29.2%)
⚪️ <1% Flu co-infections
⚪️ FYI Red bars mean *not* typed. They don't mean can't be typed

🤒1,391 (+110) isolates characterized for similarity to their corresponding vaccine components by haemagglutination lab test
⚪️ 607/628 (96.7%) A/H1N1 wild viruses were a good match
⚪️ 117/151 (77.5%) B/Victoria & (?)1/26 (96.2%) B/Yamagata wild viruses were a good match

⚪️ 242/586 (41.3%) A/H3N2 wild viruses couldn't be characterised for vax similarity because they didn't grow properly in culture
⚪️ 231/586 (39.4%) A/H3N2 wild viruses were good reactors to antibodies made in animals using vaccine component virus

⚪ +0 new H1N1s; +79 new H3N2s; +31 B/Vict; +0 B/Yama added

😷 Most 2019 #flu detections only typed (FluA or FluB)
🤧 FluA is the dominant #flu virus type this year; A/H3N2 dominating A/H1N1 subtype
🤧 FluB⬆️, comprising about third of all flu detections; B/Victoria lineage (they aren't called subtypes in B'world) dominates B/Yamagata

🤧 NOTE: A/H3N2 and B/Victoria etc are just name "boxes" or buckets. Each hold/encompass a range of distinct #flu virus genotypes. This is why a vaccine component for A/H3N2 can be quite different from the A/H3N2-dominating the flu season and yet still be called "H3N2"

😷 higher proportion of #Flu B (green) in the younger age groups (especially 5-19 years of age) and higher proportion of A/H3N2 among the elderly (65+ years)
🤒 interesting double peak among the 5-19 years-of-age group
⚪ only group still not decreasing in (+) numbers