What is bird flu?

Bird flu (avian influenza) is an infectious viral disease which has been found in certain regions, eg, Asia and Africa. The ‘H5N1’ is an aggressive strain of bird flu which can be passed from wild birds to domestic poultry. Humans have caught H5N1 bird flu from contact with infected poultry, causing illness and death in some cases. The H5N1 virus is thought to be capable of mutating, which could mean it would be spread more easily among humans. Bird flu is being monitored globally by several international agencies.

How are humans affected?

Humans are not usually at risk from bird flu, and many types of bird flu only affect wild birds such as ducks and geese, and do not cause severe illness (virus has low pathogenicity). However, the H5N1 strain has ‘high pathogenicity’ causing severe disease and usually death in susceptible species of poultry.

The H5N1 strain can infect people who are in contact with infected poultry (live or dead) or contaminated environments, eg, contact with droppings from infected birds. People likely to be at higher risk are those working in or visiting poultry farms, poultry processing areas or those with backyard poultry in affected countries/regions.

In humans, the H5N1 strain can lead to pneumonia, organ failure and death. The incubation period for H5N1 in humans may be longer than for seasonal influenza, but once symptoms develop it can progress rapidly. Initial symptoms may include high fever and are similar to that for seasonal influenza.

Risk of virus mutating

The H5N1 virus is not transmitted through the airborne route, as in human seasonal influenzas. However, concern exists that the H5N1 virus could mutate in the future, possibly ‘combining’ with a human influenza, and thus making it easily transmitted among humans. If this were to happen, it could lead to a pandemic.

How many people have been affected?

The World Health Organization (WHO) figures for ‘confirmed human cases of avian influenza’ worldwide from 2003 to early October 2011 show a total of 566 cases over this period, with 332 deaths.

Which countries have reported H5N1 bird flu?

The highest number of H5N1 bird flu cases in humans, as quoted in the WHO figures, have occurred in Indonesia, with 179 cases and 147 deaths. This is followed by Egypt with 151 cases and 52 deaths, and Vietnam with 119 cases and 59 deaths (cumulative totals, ie, not all occurring in one year). [WHO figures current at 10 October 2011].

Other countries listed by WHO as having had confirmed H5N1 bird flu cases in humans include China, Cambodia, Thailand, Turkey, Azerbaijan, Iraq, Lao PDR, Pakistan, Bangladesh, Dijibouti, Nigeria and Myanmar (note: some of these countries have not had reported cases in the last few years, but have had cases previously).

When did it begin?

The first reports of H5N1 bird flu were in 1997 in Hong Kong, found in poultry on farms and in live animal markets. The same year, the first human infections with H5N1 were reported in Hong Kong, with 18 cases and 6 deaths.

A re-emergence of the disease was seen in 2003 and 2004, with it spreading to many parts of the world, eg, Asia, the Middle East, and Africa. Many poultry have been culled in affected regions, to prevent spread or contain outbreaks of the infection.

The latest cases of H5N1 in humans are reported in Indonesia, with several deaths occurring (WHO update, 26 October 2011).

Monitoring bird flu

The World Health Organization is one of several agencies monitoring bird flu globally. The other main agencies involved are the Food and Agriculture Organization of the United Nations (FAO), and the World Organisation for Animal Health (OIE).

Hygiene and food safety

International travellers should follow general measures around normal hygiene, thorough handwashing and drying (or using alcohol-based hand sanitisers if soap and water are not available). Food and water safety is important for all travellers. In addition, for bird flu prevention, measures include avoiding contact with poultry in homes, farms or markets overseas, and ensuring chicken and eggs are well cooked before eating.

More information for travellers

People planning international travel should refer to the New Zealand Government website www.safetravel.govt.nz to check if there are any travel advisories for certain regions. This includes advice on avian influenza (under "before you go" tab), as well as any natural disasters or other problems that may be current overseas.

Antivirals

Antiviral medications, eg, oseltamivir (Tamiflu) can lessen the severity and duration of seasonal influenza, and may have some effect against bird flu. General recommendations are that this would be most effective if taken in the first 48 hours of symptoms starting. Ask your doctor or pharmacist for individual advice.

Possible infection after travel

Anyone who has returned from overseas and has symptoms of influenza or who feels unwell, should phone their GP’s surgery for advice. Always phone first and tell them you have been overseas and are unwell, so they can take precautions on your arrival in case you have influenza or another infectious illness.
 
You can also phone Healthline free (in New Zealand) on 0800 611 116 for advice. Calls are answered by registered nurses or other health professionals.

Hygiene measures for any flu

If you or a member of your household has influenza of any type, follow general hygiene measures (if a pandemic situation occurred, the Ministry of Health or other agency would also likely issue specific directions).

General measures include:

• stay at home to prevent spread
• keep coughs and sneezes covered and dispose of tissues in a covered container
• wash hands regularly with soap and water or alcohol-based sanitiser
• give the affected person plenty of fluids
• phone your doctor or practice nurse for advice, also if the person has other medical conditions and/or their condition appears to get worse
• you can also phone Healthline for advice, on 0800 611 116.

Also see: Influenza care and Influenza prevention

National planning

In New Zealand, the Ministry of Health (MOH) advises on its website that “it is working with the health sector and other Government agencies to ensure New Zealand is as prepared as possible for a potential pandemic”. The MOH also says it has a national pandemic plan, and District Health Boards have local plans.

Household preparedness

General preparedness on a household basis for a possible pandemic is similar to that for a natural disaster, and includes: having a good stock of water, non perishable food, a supply of your regular medicines, tissues, pain relief medicines, soap (hand sanitiser is also useful if water unavailable), clean hand towels or paper towels, a mask (for nursing unwell persons), disposable gloves (eg, for handling used tissues), rubbish bags, a list of important phone contacts including your GP’s rooms, a torch, a radio to listen for public announcements, and spare batteries.

Material compiled by everybody, November 2011.