Municipal workers gesture before spraying insecticide at the neighborhood of Imbiribeira in Recife, Brazil, January 26, 2016. The operation is part of the city's effort to prevent the spread of Zika's vector, the Aedes aegypti mosquito, according to a statement from Municipal Health Secretary. [Photo/Agencies]

RIO DE JANEIRO - Brazil is struggling to deal with a soaring number of Zika virus infections which have led to a staggering number of microcephaly cases in newborns.

The country has reported some 3,900 cases of infections, with over 300 confirmed.

Although the Health Ministry has reinforced actions against the proliferation of the Aedes aegypti mosquito, which transmits Zika and dengue, microcephaly cases in the South American country has not shown any sign of decline.

Zika was believed to reach Brazil during the World Cup in 2014. In contrast to the lethal dengue, Zika was at first taken as a lesser problem. But because the country has no antibodies against it, the disease is feared to have the potential for an outbreak.

The surging Zika cases, later found to have caused a sudden soaring increase in microcephaly cases, have become a major concern for the Brazilian health authorities in the second half of 2015.

The problem was first spotted in the Northeastern state of Pernambuco. After noticing the sudden increase in microcephaly cases, from less than a dozen per year to more than hundreds in just a few months, local pediatricians managed to make an initial association between the development and the Zika outbreak that occurred months earlier in the region.

The alarming contagious rate of the Zika virus was finally reported to the Health Ministry.