Zika, the mosquito-borne illness suspected of causing severe birth defects in Brazil, has been snagging headlines as the virus spread is gaining ground in the South American country. There are reports that with increasing number of Zika virus cases, Brazil has entered the height of the Southern Hemisphere’s summer season.

A report released by Brazilian Health Ministry Tuesday showed that more than 350 new cases of suspected Zika-related microcephaly have been reported till January 9. Health authorizes of Brazil believe virus cases have been increasing rapidly because pregnant Brazilian women are transferring microcephaly to their fetuses. International health authorities agreed with the theory given by Brazilian health authorities.

It is microcephaly that causes newborn to take birth with undersized skulls and brains. Health experts believe that babies with undersized brains may have serious health issues like learning disabilities and developmental problems.

The latest Brazilian Health Ministry’s report showed there are more than 3,500 suspected Zika-related microcephaly cases in 724 municipalities across 21 of 27 states of Brazil. The report also revealed that 46 infants with by Zika-related microcephaly have died.

“Before the explosion of cases since mid-2015, Brazil had an average 150 cases of microcephaly a year. Today I can tell you that we have 100% certainty of the connection of the Zika virus with increasing cases of microcephaly in Brazil,” Marcelo Castro, health minister of Brazil said in a statement.

Brazil is not the only country with suspected Zika virus cases as officials of Texas’ Harris County announced that a woman from Houston-area has been diagnosed with the Zika virus. The woman had travelled to El Salvador in November. The new case in Texas has signaled that the disease has started to explore the Americas. The health officials said they are tracking the case.