CARACAS - The number of people infected with the H1N1 virus in Venezuela rose sharply by 57.18 percent in a week's time, to reach 1,138 cases, the country's health ministry reported on Wednesday.

The report covering the week of May 26 to June 1 showed an increase of 414 cases, with the most affected states located along the northern coast and western Venezuela.

Health Minister Isabel Iturria called for the public to remain calm, saying the situation was "under control", as 3 million people were vaccinated in May.

The H1N1 virus first appeared in 2009 in Venezuela, infecting about 900 people and causing eight deaths.

As a particularly aggressive type of the flu virus, H1N1 is not lethal itself, but can be fatal for those whose immune systems have been already weakened by another ailment, such as cancer, AIDS or diabetes, especially for the old people and pregnant women.

In Venezuela, test methods now are short of quickly determining whether a patient has been infected by the virus, but the country reportedly has a good reserve of medicine needed to combat the disease.