Brazil is mobilizing more than 200,000 troops to go "house to house" in the battle against Zika-carrying mosquitoes, blamed for causing horrific birth defects in a major regional health scare, a report said Monday.

Soldiers will fan out to homes across Brazil distributing leaflets and dispensing advice, Health Minister Marcelo Castro was quoted as saying by the newspaper O Globo, signaling a major ramping up of efforts against the Zika virus.

Castro said that the government, under growing pressure to deal with the crisis, will also hand out repellent to at least 400,000 pregnant women on social welfare.

Zika is linked to serious birth defects, including microcephaly, in which babies born to women infected during pregnancy have abnormally small heads.

A surge in incidents across Latin America, notably in Brazil, has prompted the United States and other governments to warn pregnant women against traveling to the region -- an alarming prospect for Brazil as it gears up to welcome the Olympics to Rio de Janeiro in August.
Unlike some other international health scares, the Zika virus is not spread person to person. And for most people who get infected, the flu-like symptoms will clear up in about a week.

But the specific threat to pregnant women and their fetuses, and the seeming impossibility of avoiding mosquitoes in tropical countries, has given this crisis extra bite.

Brazil has recorded at least 3,893 microcephaly cases since an unusual spike in the rare condition was noticed in the country's northeast in October. Previously an annual average of 160 cases was the norm.

And short of not getting pregnant, there is no foolproof method for avoiding risk.

Castro said last week that the Aedes aegypti mosquito, which carries Zika and also dengue fever and the chikungunya virus, was gaining momentum.