WASHINGTON (Reuters) - The World Bank said on Thursday it is making $150 million in financing immediately available to help combat the Zika virus outbreak in affected Latin American and Caribbean countries.

Aedes aegypti mosquitoes are seen inside Oxitec laboratory in Campinas, Brazil, February 2, 2016. REUTERS/Paulo Whitaker

The multilateral lender said in a statement that it stands ready to increase its support if needed, and the initial amount is based on current demands from the affected countries and assessments from teams of experts sent there.

The World Bank also released initial projections for the economic impact of the largely mosquito-borne virus, saying it expects it to reduce the region’s 2016 economic output by $3.5 billion, or 0.06 percent of gross domestic product.

The bank estimates that governments in the region would lose a combined $420 million in fiscal revenues this year due to the virus.

Mexico and Cuba would take the worst hits by dollar value this year, it said, reducing their GDP by $744 million and $664 million, respectively, as it expects the virus to cause a drop-off in Caribbean tourism.

Belize would lose the biggest percentage of GDP, a drop of 1.22 percent, while several Caribbean island nations would see drops of similar size. Brazil, which has had the most Zika virus cases reported, is projected to lose $310 million, or just 0.01 percent of its GDP - less than the Dominican Republic, the World Bank said.

The bank’s economic forecasts, however, assume that the international response to the Zika outbreak will be swift and well-coordinated and that the most significant health risks are for pregnant women.

The World Health Organization has cited a “strongly suspected” relationship between Zika infection in pregnancy and microcephaly, a condition in newborns marked by abnormally small heads and brains that have not developed properly.

The WHO declared the outbreak a global public health emergency on Feb. 1.

Brazil has confirmed more than 500 cases of microcephaly, and considers most of them to be related to Zika infections in the mothers. Brazil is investigating more than 3,900 additional suspected cases of microcephaly.

“Our analysis underscores the importance of urgent action to halt the spread of the Zika virus and to protect the health and well being of people in the affected countries,” World Bank President Jim Yong Kim said in a statement.

In 2014, Kim criticized the world’s “disastrously inadequate response” to West Africa’s Ebola virus outbreak, saying that it caused many needless deaths.

The World Bank said its Zika financing will support a wide range of activities related to the Zika response, including surveillance of the virus’s spread, identifying at-risk people, access to family planning and public awareness.