Bird Flu

Avian Influenza (AI), commonly known as “bird flu”, is caused by infection with avian influenza Type A viruses. Strains are classified as low pathogenicity avian influenza (LPAI) or highly pathogenic avian influenza (HPAI), depending on their ability to cause disease in poultry (e.g. chickens). LPAI strains cause minimal to no signs of disease in poultry. HPAI strains on the other hand, can result in severe disease with high mortalities in poultry. In addition, different subtypes of AI viruses may be identified according to their “H” and “N” subtypes, (e.g. H5N1, H7N9).

Although AI viruses mainly infect birds, these viruses can sometimes infect people and cause illness, ranging from typical flu-like symptoms to severe respiratory disease leading to death.

It is important to note that bird flu viruses have the ability to mutate and adapt, and sometimes these changes result in the emergence of a novel (new) bird flu virus that could infect and spread between people. To date, all naturally occurring highly pathogenic strains in poultry have been associated with either the H5 or H7 subtype. When transmitted to poultry, LPAI of the H5 or H7 subtype have the potential to mutate to become HPAI or be able to infect other species of animals. For the purposes of early notification and trade, the World Organisation for Animal Health (OIE) defines avian influenza as infection caused by HPAI viruses or LPAI viruses of H5/H7 subtypes.

2. What animals can be affected by bird flu?

Many species of waterfowl, especially wild geese, ducks and swans, carry the bird flu virus naturally in their intestines and respiratory tract without showing clinical signs. Chickens are very susceptible to bird flu, which can cause them to be very sick and die.

LPAI usually causes little to mild illness in poultry and other birds. Clinical symptoms can be exacerbated by other factors such as concurrent illness. Signs include lack of energy and appetite, decreased or abnormal egg production and respiratory signs such as sneezing, coughing, eye and nasal discharge. Some infected poultry may not show any clinical signs.

Bird flu in mammals is typically uncommon, as the virus is not well-suited to infecting mammals. Nevertheless, due to various factors, more HPAI cases in mammals have been reported in recent years. Mammals generally cannot spread HPAI to other mammals; instead, they typically become infected due to the consumption of or contact with infected birds or their body fluids (e.g., faeces). This is why cases of HPAI in mammals usually only happen when there are many infected birds in the area.

3. How is bird flu spread between birds?

The virus is contagious and can be spread to susceptible birds through:

4. What are the signs that infected birds will show?

In poultry such as chickens and turkeys, HPAI usually causes severe illness; few birds in infected flocks survive. Infected poultry can show signs such as:

In wild birds, there can be a wide variation in clinical signs depending on the strain of bird flu and the species of bird infected. Some wild birds show little or no signs of illness if infected. Others may become very ill and show clinical signs similar to those seen in infected poultry. To verify that Singapore remains free of bird flu, AVS undertakes regular monitoring of resident and migratory birds. There have been no reports of HPAI in Singapore to date.

5. What are the signs that infected mammals will show?

HPAI infections in mammals have wide variation in clinical signs. Even within the same species, some animals may have only mild illness while others may become very sick. In general, HPAI-infected mammals may show some or all of the following signs: 

4. Are there guidelines to cooking poultry?

Consumers are advised to cook poultry meat thoroughly, practise good food hygiene and keep raw meat and other foods separate. Also, thorough cooking helps to kill any harmful germs present. The eating of any raw or semi-cooked food, including eggs, comes with an inherent food safety risk.

5. What precautions should be taken when working with poultry?

To minimise public health risks, people working in close contact with poultry are advised to observe good personal hygiene and take necessary precautions when handling poultry.

The use of gloves when handling poultry and washing of hands after handling poultry are highly recommended. Other appropriate personal protective equipment includes N95 masks, disposable gowns, shoe covers, and goggles, which adequately protect workers from potential exposure.

Pet Poultry and Other Pet Birds

1. I/My neighbour/My school owns some pet birds or poultry. Is it safe to continue keeping them? Will these pets pose a risk to the public?

Given Singapore's current bird flu free status, and the various disease prevention measures and conditions already put in place, pet birds and poultry kept in Singapore currently do not pose a risk to the general population.

Bird flu can be spread by wild migratory birds. Owners should ensure that any pet birds are kept within bird-proof cages or enclosures with:

Also, owners should not introduce birds of unknown origin to their existing pet birds.

Anyone who handles pet birds should also practise good hygiene, such as washing hands thoroughly with soap before and after handling their pets.

Owners should also engage a veterinarian for assistance, should any birds start showing signs of sickness and/or if they have concerns regarding the health of the birds.

No more than 10 poultry (including chickens) are allowed to be kept in any premises. On top of this, owners are also subjected to rules of the managing body of the premises, which may or may not allow the keeping of poultry within their managed areas.

2. How does AVS ensure that the ornamental/pet birds that are imported into Singapore are free from bird flu?

Ornamental birds are allowed to be imported into Singapore only from sources free of bird flu. The birds are also subject to pre-export quarantine and testing for bird flu to ensure that they are free from bird flu before they are exported to Singapore. In addition, AVS follows up with further checks when the consignments arrive in Singapore.

3. What should I do if my pet bird falls sick or dies?

If your pet bird is sick, bring it to the veterinarian. If you have more than one bird, separate the healthy birds from the sick birds if possible. The birds should be kept in enclosures that are not adjacent to each other. As a general precaution, adopt hygiene practices such as washing hands thoroughly with soap and water after handling the birds and the cage.

When handling dead pet birds, the following steps must be observed:

4. What should I do if I don't want to keep my birds anymore?

It is against the law to abandon animals. You should rehome them.

Visits to Nature Reserves, Bird Paradise, Zoo, etc

1. Bird flu is usually spread by migratory birds. Is it safe to go to Sungei Buloh Wetland Reserve or other parks and reservoirs?

Singapore is free from bird flu. It is safe to visit Sungei Buloh Wetland Reserve and other parks and reservoirs, as it is unlikely that visitors would catch avian flu from wild birds.
Human infections have mostly occurred after close contact with infected poultry. In addition, there is an on-going surveillance programme for bird flu in wild birds at Sungei Buloh Wetlands Reserve where swabs are collected regularly from wild birds for testing.

For the safety of wildlife and of yourself, please be reminded not to touch or handle any wild birds.

2. Is it safe to visit Bird Paradise and the Zoo?

Singapore is free from bird flu. It is safe to visit Bird Paradise and the Zoo. AVS works closely with Mandai Wildlife Group on surveillance to prevent the introduction of bird flu.

Actions Taken by AVS and SFA

1. What is AVS doing to prevent the introduction of bird flu into Singapore?

AVS has in place measures to prevent the incursion of bird flu. Preventative measures include banning the import of live birds, poultry and poultry products from countries or regions affected by bird flu, as well as inspection and sampling at points of entry, local poultry slaughterhouses and poultry farms. Farms and slaughterhouses are also required to ensure that biosecurity measures are in place, and the public is not allowed to visit these establishments. AVS and SFA work closely to ensure that these measures are implemented in the local farms and slaughterhouses. Additionally, AVS regularly inspects pet shops that sell birds to ensure they are free from bird flu. AVS also conducts regular checks and surveillance on migratory birds as well as common birds such as crows, mynahs and pigeons.