EDMONTON (CBC) - Alberta children under 10 with chronic health conditions and parents of babies will be able to get a swine flu vaccination, starting Tuesday.

The list of those eligible for the vaccine is expanding, Alberta health officials announced Friday.

Pregnant women and children under five will continue to be offered the shot, which targets the strain of H1N1 influenza A virus responsible for the current swine flu pandemic.

Infants under six months can't be immunized, so either both parents, or one parent and one caregiver will be offered the shot.

"The vaccine supply issue that we're facing is forcing us to make some very difficult decisions," said Alberta's chief medical officer of health, Dr. André Corriveau.

"If it was up to us, we would be providing vaccine to everyone who wants it immediately. But we have to face the reality that we're dealing with a supply that is coming in one bit at a time."

The province will not make the vaccine available to other high-risk groups until more of it becomes available from the manufacturer.

Parents don't have to bring their babies to the clinics but they will need to provide proof of the baby's age, such as a birth certificate. Caregivers attending clinics alone will need photo identification and a letter from the parent or guardian confirming their role.

Children who are under 10 as of Nov. 1 with medical conditions that put them at greater risk of severe illness from H1N1 will also be able to get immunized. Parents will need to provide proof of age and a prescription or other record of the childs medical condition.

Two more people in Alberta have died from complications related to swine flu, health officials said Friday, bringing the total deaths in the province to 20 since the outbreak began in April.

Besides the two deaths, Alberta is reporting that 41 people have been treated in hospital because of the flu, bringing the total so far this year to 480. The median age of hospitalized cases is 31. Most of the people who are in hospital, or have died from H1N1, had underlying health conditions.

On Thursday, health officials said about 25 per cent of the people in the province's intensive-care units are either confirmed to have, or suspected of having, the virus.

Last week, the vaccine was offered to any Albertan older than six months, and people waited in massive lines to get the shot. Alberta Health Services abruptly closed all of Alberta's clinics on the weekend, blaming a shortage of vaccine and overwhelmed staff.

Clinics across the province reopened Thursday for very young children, providing 35,000 doses of the vaccine.

On Friday, Alberta expanded its H1N1 vaccination program to include pregnant women, who are being offered a form of the vaccine without an adjuvant, an additive that boost's the body's response to the vaccine.

At Calgary's six vaccination clinics, lines were mostly moving quickly Friday.

"I've been here maybe 45 minutes," said Pat Clendon, who was at the Brentwood Village Mall. "They gave me two wristbands and an informed-consent form to read, and it sounds like there will be minimum paperwork upstairs, and we can get right to business."

Vaccination of pregnant women and young children will continue through the weekend. Locations and times of the clinics are available on Alberta Health Service's website.