Transcript H1N1 Presentation Primary Care
Pandemic (H1N1) 2009 Presentation (Massey University)
29 July 2009 Tui Shadbolt BHlthSci, MVS (candidate) Coordinator Health Protection MidCentral Public Health Service
Seasonal influenza
• Relatively minor epidemics of influenza typically occur in NZ during winter • Predominantly affects the elderly and very young • Serious illness in those with underlying illnesses and in pregnancy
Seasonal Influenza
• Between 10 and 20% of the population are infected with influenza each year – (380,000 to 760,000 people). • On average, 2.7% of the population (53,000 to 156,000 people) will consult a GP because of influenza each year (1990-99) • 266 to 874 New Zealanders end up in hospital each year because of influenza • 4 to 95 New Zealanders could die as a result of being infected with influenza.
NZ Influenza-like-illness Sentinel Surveillance
• 2008 estimated ~48 000 ILI presentations to general practice (~33 000 in 2007) – 1.2% population – Deemed moderate • Currently ILI is similar to 2008 (up to 12 June) • Seasonal A(H1N1) has gene for resistance to Tamiflu
Seasonal Vaccine
• Protective against the resistant A(H1N1) • Too early to determine match with circulating strains • Vaccination period being extended to September
Pandemic Influenza
• Global disease outbreak – Causing disease in many parts of the world • Can only occur when 3 conditions have been met: – New influenza virus subtype emerges – Infects humans, causing significant morbidity and/or mortality – Spreads easily and sustainably among humans
20
th
Century Pandemics
• 1918 (Spanish Flu) – 40-50 (poss 100) million deaths worldwide – 8000 + deaths in NZ (>0.8% population) • 1957 (Asian Flu) – High illness rate, low death rate • 1968 (Hong Kong Flu) – Relatively benign
Pandemic (H1N1) 2009
• New influenza virus, first detected in April 2009 in Mexico and shortly after in the USA • Referred to as “swine flu” because preliminary laboratory testing showed that many of the genes were similar to influenza viruses that normally occur in pigs in North America • Further testing has shown that this new virus contains two genes from flu viruses that normally circulate in pigs in Europe and Asia and avian genes and human genes (“quadruple reassortment” virus)
Pandemic (H1N1) 2009
• Symptoms – Flu symptoms: fever, cough, sore throat, runny/blocked nose, headache and body aches, fatigue, vomiting/diarrhoea • Infectious period – 1 day before until generally 4 days after symptom onset (potentially up to 7 days & longer in children <5yrs) • Incubation period – Usually within 3-4 days of exposure, but potentially up to 7 days
MDHB Confirmed H1N1 Rate to 22-07-09 by Age Group
70 60 50 40 30 20 10 0 < 1 1 to 4 5 to 1 4 15 to 2 4 25 to 4 4 45 to 6 4 65 +
Age Group Years
50 40 30 20 10 0
MDHB Rate Confirmed H1N1 to 22-07-09 by Ethnicity
European Maori Pacific
Ethnicity (prioritised)
Other
40 35 30 25 20 15 10 5 0
MDHB Confirmed H1N1 Rate to 22-07-09 by TA (excludes Kapiti Portion of MDHB)
Horowhenua District Manawatu District Palmerston North City
Territorial Authority
Tararua District
How Infectious is Pandemic (H1N1) 2009?
• Reproductive number – Measures how many cases a single infectious case causes in a susceptible population • Seasonal Influenza R=1.2-1.4
– Partially susceptible population • Estimates for Mexico 2.2-3.1 (Eurosurveillance) 1.4-1.6 (Science) • Estimate for New York School 2.7
Phase changes
Trigger for phase change – Resources overwhelmed for stamp it out phase • Public health, primary care, laboratory and other support services – Evidence of sustained community transmission • Cases identified with no epidemiological link to confirmed case or travel history • Sentinel GP influenza-like-illness surveillance • Routine ILI viral swabs
Phases so Far
• “Keep it out” – Border response • “Stamp it out” – Border response (intense) – Contact tracing – Tamiflu (treatment and prophylaxis) – Quarantine and isolation • “Manage it” – Cluster control – High risk institutions – Tamiflu (severe illness, underlying illness, high risk institutions – minimal prophalaxis)
CIMS
• NHCC activated on the 25 April combined Keep it out/stamp it out • New Zealand went to Manage it phase 19 th June 2009 • MidCentral PHS activated 27 th April – the last region to identify community spread within sentinel surveillance sites moved to “manage it” on 2 July 2009
New Zealand Cases
As at 1500hrs 28 July 2009
• 2704 Confirmed cases • 13 Deaths
MidCentral PHS case numbers
• 61 confirmed cases • 1 Death • 60 (Wanganui) • 0 Deaths
Isolation
• Reduce close contact with other people as much as possible – Separate rooms – Avoid communal eating – Staying at least 1 metre away wherever possible • Preferable length of isolation is until no longer considered infectious – Children <5yrs old infectious longer (5 days of treatment or symptom free) – Adults without treatment (considered no longer infectious after 7 days or if well) – Vulnerable treated with Tamiflu and recovered (72 hrs or symptom free whichever is longest)
Strategies to manage isolation
Staff
• Reinforce sickness policy i.e. don’t come to work if you are sick
Students
• Reinforce “don’t come to lectures or communal spaces if you are sick” • Taped lectures (for anxious conscientious students) • Food eaten in rooms • Increased cleaning in affected hostels • Separating ablutions for those well and those who are sick • Rubbish bags in open bins for easy disposal of tissues • Easy access to hand washing facilities and handsanitiser • Surgical masks for sick people when outside rooms
Infection Control when dealing with people with ILI
• Physical Distancing • Isolation • Hand hygiene • Cough/sneezing hygiene • Ventilation • PPE • Cleaning
Key messages
If/when Massey has an outbreak
• Standard precautions – Resources – Knowledge • Case logs in hostels – For knowledge about those who are sick • Staff and residents – Information on how the outbreak progresses and when it ends • Liaison with Public Health – How/if we use of National stockpile of Tamiflu and its release
Signs and Symptoms
Symptoms are the same as for normal seasonal flu
Signs and symptoms of the new Influenza A (H1N1) virus are similar to the symptoms of seasonal flu and can include: • fever (a temperature ≥38 °C), cough, sore throat, runny or stuffy nose, body aches, headache, chills, fatigue.
• Some people also experience diarrhoea and vomiting.
Also, like seasonal flu:
• the worst symptoms usually last about five days, but coughing can last up to two to three weeks • some very young children, people with some long-term medical conditions, pregnant women, and older people, can get very sick
Care of those unwell in hostels
• Mild Flu like illness in most people –
Fever can be managed with fever lowering meds such as paracetamol
–
Important for them to be well hydrated (access to hydration drinks)
– Health line Number 0800 611 116 • Those who develop severe symptoms and you /or them have concerns for their health – Ring the health line, Massey Doctor or A/H call the Emergency – department advise severe ILI symptoms (wear a mask if going) • Those who are pregnant or have underlying illnesses most at risk
e.g. Asthma, diabetes, chronic illness or are immunocompromised - can these be identified These people need to be medically assessed within 48 hours of onset of illness – ring the Dr for an appointment advise ILI
–
They need to have good monitoring of the progression of their illness if they deteriorate seek medical help
Health Line Phone Number
• • •
0800 611 116
Health line is a free service operates 24 hours a day, 7 days a week staffed by registered nurses If the wait is a long time and you have concerns for your health ring the DR or ED
What are the symptoms of most
concern
and likely to indicate the need for urgent medical assessment
• starts to feel better, then gets worse • has a temperature of 38°C or greater • has chills or severe shaking • has difficulty breathing or chest pain • has purple or blue discolouration of the lips • is less responsive than normal, is unusually quiet, or becomes confused • is vomiting and unable to keep liquids down • has signs of dehydration such as dizziness when standing, not urinating, and in infants, a lack of tears when they cry • has seizures or convulsions.
Resources
• Travel – www.safetravel.govt.nz
• General Queries from Public – Healthline 0800 611 116 – www.moh.govt.nz
• CBAC planning – Frances Guthrie at Compass Health first point of contact • Public Health Surveillance Weekly Update – http://www.surv.esr.cri.nz/virology/influenza_weekly_update.php
• Information Sheets