In a first in Singapore, a person with no underlying conditions has been taken seriously ill with Influenza A (H1N1).
The victim is a 22-year-old woman who is six months' pregnant. She developed pneumonia and tested positive for H1N1 at a private hospital.
She was admitted to KK Women's and Children's Hospital (KKH) on Monday.
A day later, she was transferred to the hospital's intensive care unit (ICU) for closer monitoring as her need for oxygen increased.
Pregnant women are considered high-risk and should consult their specialist if they have flu-like symptoms. If complications develop, they should call an ambulance immediately.
In this case, the mother-to-be was sent to the hospital's ICU because her condition had deteriorated.
She is one of two women who are critically ill with the virus, the Ministry of Health said yesterday.
The other is a 45-year-old with a slew of medical conditions: Diabetes, hypertension, high cholesterol and peripheral vascular disease, which develops when the arteries which supply blood to the legs become blocked.
She was also on immunosuppressants as she had undergone a kidney transplant in 2006.
She went to the Singapore General Hospital's emergency department on July4 after vomiting and suffering from diarrhoea for two days, and was admitted.
But her condition worsened, and she was transferred to the ICU on Sunday.
Laboratory tests later confirmed that she was infected with H1N1.
The latest cases bring the number of people critically ill with H1N1 in Singapore to three. The third is a 51-year-old man who was admitted to Changi General Hospital's ICU last Thursday.
His condition is now stable, but he remains in the ICU.