MANILA - The Department of Health (DOH) on Wednesday said high-ranking officials will be reassigned amid ongoing investigations.

In a statement, the DOH vowed that it is "not taking allegations of impropriety lightly."

"I am re-assigning certain undersecretaries, assistant secretaries and directors of the Department of Health in order to preserve the integrity of ongoing investigations and to prevent any potential undue influence on their findings," Health Secretary Francisco Duque III said.

The DOH said two senior officials of the Food and Drug Administration were reassigned last week upon the recommendation of the agency's director general.

"I respect the recommendation of the director general to support any efforts in ensuring that ongoing investigations remain fair and transparent and immune to undue influence," Duque said.

Dr. Francis Cruz, a former DOH consultant, claimed that at least 18 incumbent and former officials profited from the government's controversial P3.5-billion dengue vaccine program.

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Duque has promised to probe the allegation once Cruz is able to present documentary evidence.

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The nationwide immunization program was halted early December a few days after Sanofi Pasteur, makers of Dengvaxia, the vaccine procured for the initiative, bared that the drug could cause more severe symptoms if administered on those who have not had dengue.

As of November, the vaccine has been given to about 830,000 children in Metro Manila, Southern Luzon, Central Luzon and Central Visayas, per government data.

Two House panels and the Senate have conducted separate inquiries into the controversial vaccine program.