New Delhi, July 29 - The Indian health ministry Wednesday asked educational institutes not to shut but take preventive measures to control the swine flu spread as 23 new cases of the influenza A(H1N1) were reported, taking the tally of the infected people in the country to nearly 500.

The government reiterated its advisory against visiting the flu-affected countries.

The total influenza A(H1N1) virus cases have reached 498 in India, a statement said.

'About 2,252 persons have been tested so far, out of whom 498 are positive for the virus. Of the 498, 273 have been discharged,' the statement said.

Twelve children were among 23 new positive cases reported Wednesday , with Pune for the third consecutive day registering the maximum cases. Eleven people, including nine children, tested positive in the Maharashtra city, already declared a hit by the pandemic.

Seeing a surge in the number of cases among students, the health ministry asked educational institutes not to shut but take preventive measures to control the swine flu spread. It advised students to avoid study tours to the infected countries.

An official circular said: 'Given the current magnitude of the spread of A(H1N1) infection and the fact that the virus is fairly mild, closure of educational institutions on account of any student/staff member falling ill with flu like symptoms is not recommended.'

The guideline, however, said educational institutes are encouraged to report the flu cases to local health officers for further monitoring.