Pernambuco has declared a state of emergency in order to speed up efforts in responding to Zika fever. The mosquito-borne virus from Africa has already been linked to an increased number of birth defects.

BBC reports that the Brazilian state has reported around two thirds of the cases of micro-encephalitis, which is a condition that causes an inflammation of the foetal brain, which can stunt the growth of the baby's head.

The reports said that a team from the World Health Organization (WHO) is due to arrive in Brazil this week.

The Brazilian Health Ministry said on Saturday that the link between Zika fever and birth defects was unfamiliar.

The Brazilian Health Ministry also said that it had already reported two deaths in adults as well as 1,248 cases of micro-encephalitis this year. The numbers have increased eight-fold since last year.

Most of the reported cases of micro-encephalitis have been seen in Brazil. However, the cases seem to be rapidly appearing towards the south-eastern parts of Brazil, including  Rio de Janeiro and Sao Paulo.

The Zika virus was first recorded in Brazil in April of this year and has since spread to 13 states, Sci Dev reports.

Preliminary analysis has suggested that the greatest risk of contamination happens within the first three months of pregnancy. Despite initial health warnings, it is considered less dangerous, so that reporting it is not obligatory in Brazil. 

The Brazilian Health Ministry also reported that 199 municipalities around Brazil, particularly in the northeast, southeast, and Amazon regions, have the highest risk of being hit by these diseases in the coming months.

Victims are said to not feel the symptoms at first, as it appears relatively harmless. Victims are said to have experienced a rash and then a fever after a few days. Ministry officials have already issued warnings to women who are thinking about getting pregnant, particularly in the areas most affected by Zika fever. Rural communities are at most risk of being affected by the virus, the Brazilian Health Ministry has reported. 

Zika is said to be transmitted by the Aedes aegypti mosquito, which are also known to carry air-borne diseases like yellow fever, dengue and chikungunya.

Brazil's Ministry of Health added that Zika fever has posed a serious threat to public health. The Health Ministry has urged government officials to step up on emergency procedures to control the Aedes aegypti mosquito to prevent Zika fever from spreading any further.