Three more cases of A/H1N1 influenza have been confirmed in the state of Oklahoma, the state department of health said on late Thursday.

The new cases, which bring the state's total to four, were a student at Deer Creek school in Oklahoma County, a woman and an unrelated teenage girl in Cleveland County, according to Pam Williams, spokeswoman for the state health department.

None of them required hospitalization and all have fully recovered, she added.

An earlier case, confirmed on Tuesday, involved a woman in Pontoc County who also recovered without hospitalization.

The girl at Deer Creek school did not attend school while suffering symptoms of the flu, which she likely got from contact with a relative who had been to Mexico, local officials said.

The virus has killed two people in Texas in the United States and 42 people in neighbouring Mexico.

As of Thursday, 41 states in US have reported 896 confirmed cases of A/H1N1 flu, according to the Centers for Disease Control and Prevention (CDC).

Williams emphasized that the virus is behaving much like the regular, seasonal flu, and people should take similar precautions. "We just want people to stay calm," she said.

Earlier this week, Oklahoma State University announced administrators will not be shaking graduates' hands during their commencement activities this weekend to protect against possible exposure to A/H1N1 flu. The university has also canceled all tripsit sponsored to Mexico through the summer.

Since the virus seems not as deadly as predicted, the CDC now does not recommend closing schools when a case is confirmed, leaving local officials to make decision, according to a press release from the state health department.

The department at the same time warns people that there is no vaccine to prevent A/H1N1 flu, and the seasonal flu vaccine does not protect against it.

(Xinhua News Agency May 8, 2009)