The patients have been categorised as follows:

Category A: Patients with mild fever plus cough/sore throat with or without body ache, headache, diarrhoea and vomiting will be categorised. They do not require Oseltamivir and should be treated for the symptoms mentioned above. The patients should be monitored for their progress and reassessed at 24 to 48 hours by the doctor.

No testing of the patient for H1N1 is required. Patients should confine themselves at home and avoid mixing up with public and high risk members in the family.

Category B: (i) In addition to all the signs and symptoms of Category A, if the patient has high grade fever and severe sore throat, may require home isolation and Oseltamivir;

(ii) In addition to all the signs and symptoms of Category A, individuals having one or more of the following high risk conditions shall be treated with Oseltamivir: children under five, pregnant women, those above 65 years, those with lung diseases, heart disease, liver disease, kidney disease, blood disorders, diabetes, neurological disorders, cancer and HIV/AIDS; Patients on long term cortisone therapy.

No H1N1 tests are required for Category-B (i) and (ii). Such patients should confine themselves at home and avoid mixing with public and high-risk members in the family.

Category C: In addition to the symptoms of Categories A and B, if the patient has one or more of the following:

–Breathlessness, chest pain, drowsiness, fall in blood pressure, sputum mixed with blood, bluish discolouration of nails;

– Irritability among small children, refusal to accept feed;

– Worsening of underlying chronic conditions.

Such patients require testing, immediate hospitalisation and treatment.

RECOMMENDATIONS FOR PUBLIC HEALTH PERSONNEL
For interviews of healthy individuals (i.e. without a current respiratory illness), including close contacts of cases of confirmed swine influenza virus infection, no personal protective equipment or antiviral chemoprophylaxis is needed. See section on antiviral chemoprophylaxis for further guidance.

For interviews of an ill, suspected or confirmed SIV case, the following is recommended:

1. Keep a distance of at least 6 feet from the ill person; or
2. Personal protective equipment: fit-tested N95 respirator [if unavailable, wear a medical (surgical mask)].

For collecting respiratory specimens from an ill confirmed or suspected SIV case, the following is recommended:

1. Personal protective equipment: fit-tested disposable N95 respirator [if unavailable, wear a medical (surgical mask)], disposable gloves, gown, and goggles.
2. When completed, place all PPE in a biohazard bag for appropriate disposal.
3. Wash hands thoroughly with soap and water or alcohol-based hand gel.

Infection Control
Recommended Infection Control for a non-hospitalized patient (ER, clinic or home visit):

1. Separation from others in single room if available until asymptomatic. If the ill person needs to move to another part of the house, they should wear a mask. The ill person should be encouraged to wash hands frequently and follow respiratory hygiene practices. Cups and other utensils used by the ill person should be thoroughly washed with soap and water before use by other persons.

Recommended Infection Control for a hospitalized patient:

1. Standard, Droplet and Contact precautions for 7 days after illness onset or until symptoms have resolved.
2. In addition, personnel should wear N95 respirators when entering the patient room.
3. Use an airborne infection isolation room (AIIR) with negative pressure air handling, if available; otherwise use a single patient room with the door kept closed.
4. For suctioning, bronchoscopy, or intubation, use a procedure room with negative pressure air handling.

Recommended PPE for personnel providing clinical care to ill individuals:

1. Disposable gown, gloves, goggles, N95 respirator.

Antiviral Treatment
Antiviral treatment for confirmed or suspected ill case of swine influenza virus infection may include either oseltamivir or zanamavir, with no preference given at this time. Recommendations for use of antivirals may change as data on antiviral susceptibilities become available.

Initiate treatment as soon as possible after the onset of symptoms.

Oseltamivir:

1. The treatment dosing recommendation for children who weigh 15 kg or less is 30 mg twice a day. For children who weigh more than 15 kg and up to 23 kg, the dose is 45 mg twice a day. For children who weigh more than 23 kg and up to 40 kg, the dose is 60 mg twice a day. For children who weigh more than 40 kg, the dose is 75 mg twice a day.
2. For ages 13 years and older: 75mg twice a day for five days

Zanamivir is an alternative for treatment of influenza in patients aged 7 years and older; dosage varies by age. This drug is not approved for treatment of influenza in children aged <7>

1. The treatment dosing recommendation for persons aged 7 years and older is 2 inhalations twice a day for five days (2 inhalations of 5mg each twice a day for five days)

Antiviral Chemoprophylaxis
Antiviral chemoprophylaxis (pre-exposure or post-exposure) can be considered for close contacts of a confirmed or highly suspected case of swine influenza virus infection.

Close contact is defined as: within about 6 feet of an ill person who is a confirmed case of swine influenza A virus infection (e.g. post-exposure chemoprophylaxis following unprotected close exposure).

Duration of antiviral chemoprophylaxis is 7 days after the last known exposure

Oseltamivir: Administered by mouth once a day for seven days following the last known exposure; dosage varies by age and weight for children aged 1 year to 12 years (available in suspension, 30mg, 45mg, 75mg capsules)

1. The chemoprophylaxis dosing recommendation for children who weigh less than 15 kg is 30 mg once a day. For those who weigh more than 15 kg and up to 23 kg, the dose is 45 mg once a day. For children who weigh more than 23 kg and up to 40 kg, the dose is 60 mg once a day. For children who weigh more than 40 kg, the dose is 75 mg once a day.
2. For ages 13 years and older: 75 mg once a day for seven days

Zanamivir is an alternative for chemoprophylaxis for patients aged 5 years and older; dosage varies by age. It is an orally inhaled drug that is administered using a disk inhaler device.

1. Dosing is 2 oral inhalations once a day for seven days (2 inhalations of 5mg each once a day for seven days)

Follow-up Monitoring of Exposed Close Contacts
Close contacts are defined as persons who were within about 6 feet of the confirmed swine influenza case while the case was ill up to 7 days after the case’s illness onset. Examples include household members, social contacts, public health care workers, medical health care workers, and others.

1. Close contacts should be monitored daily for fever (temp ≥38.0 ºC) and/or any respiratory symptoms up to 7 days following the last known exposure to an ill person who is a confirmed case of swine influenza virus infection.
2. Close contacts of an ill person who is a confirmed case of swine influenza virus infection should be educated about the signs and symptoms of swine influenza virus infection and advised to contact public health staff if fever or feverishness or any respiratory tract symptoms occur up to 7 days following the last known exposure to the ill case.

What is the new influenza A(H1N1)?

This is a new influenza A(H1N1) virus that has never before circulated among humans. This virus is not related to previous or current human seasonal influenza viruses.

How do people become infected with the virus?

The virus is spread from person-to-person. It is transmitted as easily as the normal seasonal flu and can be passed to other people by exposure to infected droplets expelled by coughing or sneezing that can be inhaled, or that can contaminate hands or surfaces.

To prevent spread, people who are ill should cover their mouth and nose when coughing or sneezing, stay home when they are unwell, clean their hands regularly, and keep some distance from healthy people, as much as possible.

There are no known instances of people getting infected by exposure to pigs or other animals.

The place of origin of the virus is unknown.

What are the signs and symptoms of infection?

Signs of influenza A(H1N1) are flu-like, including fever, cough, headache, muscle and joint pain, sore throat and runny nose, and sometimes vomiting and diarrhoea.

Why are we so worried about this flu when hundreds of thousands die every year from seasonal epidemics?

Seasonal influenza occurs every year and the viruses change each year - but many people have some immunity to the circulating virus which helps limit infections. Some countries also use seasonal influenza vaccines to reduce illness and deaths.

But influenza A(H1N1) is a new virus and one to which most people have no or little immunity and, therefore, this virus could cause more infections than are seen with seasonal flu. WHO is working closely with manufacturers to expedite the development of a safe and effective vaccine but it will be some months before it is available.

The new influenza A(H1N1) appears to be as contagious as seasonal influenza, and is spreading fast particularly among young people (from ages 10 to 45). The severity of the disease ranges from very mild symptoms to severe illnesses that can result in death. The majority of people who contract the virus experience the milder disease and recover without antiviral treatment or medical care. Of the more serious cases, more than half of hospitalized people had underlying health conditions or weak immune systems.

Most people experience mild illness and recover at home. When should someone seek medical care?

A person should seek medical care if they experience shortness of breath or difficulty breathing, or if a fever continues more than three days. For parents with a young child who is ill, seek medical care if a child has fast or labored breathing, continuing fever or convulsions (seizures).

Supportive care at home - resting, drinking plenty of fluids and using a pain reliever for aches - is adequate for recovery in most cases. (A non-aspirin pain reliever should be used by children and young adults because of the risk of Reye's syndrome.)

Use of pandemic influenza A (H1N1) vaccines

Up-to-date as of 23 July 2009 (Originally posted on 2 May 2009 and revised on 27 May and 12 July 2009)

Will it be possible to deliver influenza A (H1N1) vaccine simultaneously with other vaccines?

Inactivated influenza vaccine can be given at the same time as other injectable non-influenza vaccines, but the vaccines should be administered at different injection sites. Advice is being developed at present by regulatory authorities on co-administration of pandemic and seasonal influenza vaccines and will be provided when available.

How can a person who wishes to be vaccinated against influenza A (H1N1) receive the vaccine?

Once the first doses of pandemic influenza A(H1N1) vaccine become available, national health authorities will decide how to implement national vaccination campaigns.