Influenza A (H1N1)

Influenza A (H1N1) (Swine flu)

• Swine flu is a respiratory disease of pigs

caused by Type A Influenza virus that

causes regular outbreaks in pigs

• Swine flu viruses have been reported to

spread from person-to-person, however

transmission was limited

• The current pandemic started in Mexico

in 2009 and now declared as seasonal

influenza

3

Pandemics of influenza

H7H5H9*

1980

1997

Recorded new avian influenzas

1996 2002

1999

2003

1955 1965 1975 1985 1995 2005

H1N1

H2N2

1889RussianinfluenzaH2N2

H2N2

1957AsianinfluenzaH2N2

H3N2

1968Hong KonginfluenzaH3N2

H3N8

1900Old Hong Kong influenzaH3N8

1918SpanishinfluenzaH1N1

1915 1925 1955 1965 1975 1985 1995 20051895 1905 2010 2015

2009PandemicinfluenzaH1N1

Recorded human pandemic influenza(early sub-types inferred)

Reproduced and adapted (2009) with permission of Dr Masato Tashiro, Director, Center for Influenza Virus Research, National Institute of Infectious Diseases (NIID), Japan. Animated slide: Press space bar

H1N1Pandemic

H1N1

Phases of Pandemic Influenza

Influenza A (H1N1) (Swine flu)

• Swine flu is a respiratory disease of pigs caused by Type A Influenza virus that causes regular outbreaks in pigs

• Swine flu viruses have been reported to spread from person-to-person, however transmission was limited

• During pandemic and post pandemic situation widespread human to human infection occurs

What is Influenza A (H1N1) ?

• Viral infection.• Genetic mixing of three

different viruses• Highly susceptible to

oseltamivir

Current Situation• Global

– First case reported on 18th March 2009– WHO declared Post Pandemic – June 2010

• India• Pandemic Phase – May 2009 to Dec 2010• Post Pandemic Phase – Jan 2011 – Dec 2014• Circulate as Seasonal Influenza

• Tamil Nadu• First case : 1st May 2009 & Declined in

2011• Cases continue to report sporadically

Tamil Nadu

Year Samples Positives Positivity Rate Deaths CFR

2009 23625 3047 12.9 10 0.33

2010 9630 1405 14.6 24 1.71

2011 786 34 4.3 4 11.76

2012 5058 750 14.8 40 5.33

2013 2528 37 1.5 6 16.22

2014 1363 58 4.3 8 13.79

2015* 196 36 18.4 4 11.11

*Up to 20.01.2015

Place DistributionS.no HUD

2014 2015Cases Deaths Cases Deaths

1 Chennai 18 1 7 12 Coimbatore 8 2 8 1 3 Vellore 6 - 5 -4 Erode 3 1 3 1 5 Kancheepuram 3 - - -6 Thiruppathur 3 - - -7 Thiruvallur 3 2 1 -8 Salem 2 - 2 -9 Thiruvannamalai 2 - - -

10 Villupuram 2 - 1 -

Place DistributionS.no HUD

2014 2015Cases Deaths Cases Deaths

11 Cuddalore 1 - - -12 Kanniyakumari 1 1 1 -13 Krishnagiri 1 - - -14 Namakkal 1 1 - -15 Ramnad 1 0 - -16 Saidapet 1 - 3 -17 The Nilgiris 1 - 1 -18 Thiruppur 1 0 2 1 19 Dharmapuri - - 1 -20 Madurai - - 1 -

Total 58 8 36 4

(Up to 20-01-2015)

(Up to 20-01-2015)

Laboratories Identified for Testing

Sl. No Name of the LaboratoryGovernment

1 King Institute of Preventive Medicine, Guindy Chennai2 Madras Medical College and Research Institute, Chennai3 Coimbatore Medical College, Coimbatore4 Tirunelveli Medical College, Tirunelveli5 KAP Vishwanathan Medical College, Tiruchirapalli6 Madurai Medical College, Madurai7 JIPMER, Pondycherry

Private1 Bharat Specialities Lab, Chennai2 Hitech Diagnostics Centre, Chennai3 Lister Metropolis Laboratory and Research Centre(P) Ltd4 Sri Ramachandra Medical College, Porur Chennai5 Diagnostic services, T Nagar, Chennai6 Immuno Ancillary Clinical Services, Coimbatore7 Microbiology Laboratory, Coimbatore8 Vivek Laboratory, Nagercoil9 Doctor’s Doagnostic centre, Tiruchirapalli

10 Premier Health centre, Chennai11 Star biotech solution, Chennai12 Christian Medical College, Vellore13 Narayana Hiruthayala Hospital, Kartanaka

Epidemiology of AH1N1

Case Definition*

A suspected case Acute febrile respiratory illness who• Develops symptoms within seven days of close

contact with a person who is a confirmed case of H1N1 influenza A virus infection or

• Develops symptoms within seven days of travel or resides in a community where there are one or more confirmed A H1N1 influenza cases

* CDC definition

Case Definition

• A probable case: Acute febrile respiratory illness who is

positive for influenza A, but negative for H1 and H3 by RT-PCR

• A confirmed case Acute febrile respiratory illness with

laboratory-confirmed H1N1 influenza A virus detection by real-time reverse transcriptase PCR (RT-PCR) or culture.

Mode of transmission

• People become infected by touching something with live flu viruses on it and then touching their mouth or nose (More than 80%)

• Viruses are spread from person to person by droplet through coughing or sneezing of people with influenza.

Communicability

• From one day before to 7 days after the onset of symptoms.

• If illness persists for more than 7 days, communicability may persist.

• Children, especially younger children, might potentially be contagious for longer periods.

Clinical features

Vomiting or diarrhea (not typical for influenza but reported by recent cases of swine influenza infection)

Other Manifestations

• Tachycardia• Tachypnoea• Low O2 sat.• Hypotension• Cyanosis• Acute myocarditis• Cardiopulmonary arrest

High Risk Group• Asthma• Pregnancy • Age above 65 Years • Children under five

years• Chronic lung disease • Chronic heart disease • Chronic kidney disease

• Chronic liver disease • Chronic neurological

disease • Immunosuppressant

(whether caused by disease or treatment)

• Diabetes mellitus • Obesity

Investigations

• Routine investigations for evaluation and management of symptoms– Hematological, bio chemical, radiological and

micro biological tests• Confirmation of influenza

– Real Time RT – PCR– Isolation of virus in culture– Four fold rise in virus specific neutralizing

antibodies

Case Management

• Prompt treatment to prevent severe illness and death

Supportive treatment (Antipyretics, antibiotics, IV fluids, Oxygen therapy, nutrition, saline gorgling, mucolytics etc)

Specific anti viral treatment (Oseltamivir)

Antiviral treatment

• Oseltamivir (Tami flu) is the drug of choice for treatment and chemoprophylaxis.

• Available in capsule (75 mg, 45 mg and 30 mg) and syrup form (60 ml bottle= 12 mg per ml)

• For treatment, antiviral drugs work best if started soon after getting sick

• Reduces the duration of virus excretion and the severity of illness

Antiviral treatment for cases

• Duration of treatment: 5 days BD• Dosage schedule

Weight Dosage<15 kg 30 mg BD 5Days

15-23 kg 45 mg BD 5Days

24 to <40kg 60 mg BD 5Days

>40 kg 75 mg BD 5Days

Antiviral treatment for cases-Infants

• Duration of treatment: 5 days BD• Available as oral suspension• Dosage schedule

Months Dosage

<3 months 12mg BD 5Days

3-5 months 20mg BD 5Days

6-11 months 25mg BD 5Days

Contact tracing and chemoprophylaxis

• Powerful public health intervention to interrupt the transmission

• All contacts of confirmed cases are to be administered with Oseltamivir (Tami flu) irrespective of whether they have symptoms or not

Antiviral dosage for chemoprophylaxis

• Duration of treatment: 10 days OD• Dosage schedule

Weight Dosage<15 kg 30 mg OD 10 Days15-23kg 45mg OD 10 Days24to<40kg 60mg OD 10 Days>40 kg 75mg OD 10 Days

Antiviral dosage for chemoprophylaxis -infants

• Duration of treatment: 10 days OD• Chemoprophylaxis not recommended for children

below 3 months generally• Dosage schedule

Months Dosage

3-5 months 20 mg OD 10 Days

6-11 months 25 mg OD 10 Days

Guidelines for hand washing in Health Care

Settings

• Use surgical spirit (70% alcohol or more)

• Wash hands before and after seeing every patient

• Discard basins with antiseptic lotions for handwashing

HAND HYGIENE

HAND HYGIENE

Disinfectants• 1 to 10% Sodium or Calcium

hypochlorite solution – for disinfecting instruments and infected body fluids

• 5% lysol – Decontamination of floor by mopping

• Surgical spirit with minimum of 70% alcohol – For disinfecting Hands

Guidelines for schools• Daily screening• Students/ teacher with flu like condition

should be sent to a doctor• Home isolation/ admission in isolation ward

as per category• Disinfect the class rooms before the

commencement of next class (Floor with 5% lysol and other surfaces including desk with

surgical spirit)

Guidelines for cinema theatres

• Disinfect the theatre before the commencement of next show

- Floor with 5% lysol or 1% hypochlorite solution - Seats, ticket counters and other surfaces with surgical spirit

Guidelines for marriage halls and other community halls

• Disinfect the hall before the commencement of next function

- Floor with 5% lysol or 1% hypochlorite solution - Seats and other surfaces with surgical spirit

Guidelines for lodging houses

• Disinfect the room before allotting to the next guest

- Floor with 5% lysol or hypochlorite solution - Seats, teapoy, TV remote, door handles and other surfaces with surgical spirit

Guidelines for Public Transport

• Disinfect the vehicle particularly the areas touched by hands at the end of every trip

- Floor with 5% lysol - Seats and other surfaces with surgical spirit

Guidelines for Public Places

• Improve general cleanliness -Floor with 5% lysol or hypochlorite solution -Seats and other surfaces with surgical spirit

• Liberal use of disinfectants

What should I do?• First and most important: wash

your hands

• Practice cough etiquette

• Avoid touching surfaces that may be contaminated with the flu virus.

• Avoid close contact with people having flu like illness

What should I do?• Staying at home if you have flu like

symptoms• Educating school children and staff, advising

avoidance of mass gatherings • Avoid crowded places, avoid hand shaking• Avoid picnics