According to the World Health Organisation (WHO), the two latest suspected cases of the human form of the bird flu virus in Indonesia and Thailand have been confirmed as the H5N1 strain of the disease.

Meanwhile China has admitted that the first case of the disease in humans there was in fact two years earlier than they originally said and a 24-year-old soldier who died in December 2003, died from the virus.

China had initially said it’s first human case was in 2005.

The admission has come about as a result of a letter published in the New England Journal of Medicine in June this year, by Chinese doctors, who claimed that a 24-year-old soldier, who was admitted to hospital in November 2003 for respiratory distress and pneumonia and later died, had been infected with the H5N1 strain.

Following the revelations in the letter the WHO has called on Beijing to re-examine other pneumonia cases of unknown origin.

However the Health Ministry has denied that the 2003 case was evidence of an outbreak and says there are no plans to review other cases.

Since late 2003 bird flu has spread rapidly from Asia to Europe, the Middle East and Africa and outbreaks have been confirmed in more than 48 countries.

It has killed 137 people and infected 235 others in Azerbaijan, Cambodia, China, Egypt, Indonesia, Iraq, Thailand, Turkey and Vietnam.

According to the World Organisation for Animal Health (OIE) since the start of 2006, more than 30 countries have reported outbreaks, most cases involving wild birds such as swans who are viewed by many experts as harbingers of disease.

Most of those who have died are children and young adults and Indonesia and Vietnam have had the highest number of cases, with a combined total of 85 deaths.

The H5N1 virus is one of many bird flu viruses which have been around since 1959.

At that time it was responsible for an outbreak of highly pathogenic avian influenza in Scotland.

An outbreak in 2003 of the H7N7 bird flu virus in the Netherlands led to the destruction of more than 30 million birds, and 2.7 million were destroyed in Belgium, and around 400,000 in Germany.

In the Netherlands, 89 people were infected with the H7N7 virus, one of whom one (a veterinarian) died.

The H5N1 virus first transferred across to humans in Hong Kong in 1997, when 18 people were infected and six died.

The culling by the government of the territory’s entire poultry flock, ended that outbreak.

Experts say the symptoms in humans can range from typical influenza-like symptoms, such as fever, cough, sore throat and muscle aches, to eye inflammations (conjunctivitis), pneumonia, acute respiratory distress, viral pneumonia and other severe and life-threatening complications.

However it is worth remembering that despite it’s spread around the globe the H5N1 virus remains a disease of mainly birds and is only contracted by contact with some aspect of infected birds and poultry.

Almost all cases of the virus to date have been contracted in such a manner.