RIO DE JANEIRO, Jan. 5 (Xinhua) -- Dengue fever cases show very rare increase in spring and late winter last year, as 123,000 new cases were registered from September to December, O Estado de Sao Paulo daily said Tuesday.
Dengue cases are common in Brazil but they usually increase during the summer months of December-February, also known as the wet season.
According to the newspaper, the country registered 1.58 million dengue cases from January to the first week of December.
Meanwhile, the number of deaths caused by dengue also saw a significant rise to 839, the highest since 1982.
Dengue is a disease transmitted by the Aedes aegypti mosquito. In addition to four types of dengue, the Aedes mosquito also transmits chikungunya fever and the zika virus.
The zika virus was previously not considered a matter of great concern, as its symptoms are not as serious as those of dengue and chikungunya.
However, months after an outbreak of zika in 2015, the country has registered an alarming number of cases of microcephaly in newborns, and a connection between the two has now been established.
Microcephaly is a condition characterized by a baby being born with a smaller cranium. It is frequently accompanied by other health conditions and can lead to cognitive delays. Brazil used to have very few cases of microcephaly, but the number of cases skyrocketed in areas where zika outbreaks had been registered months before.
Scientists from Brazil's renowned Oswaldo Cruz Institute managed to find traces of the zika virus in the amniotic fluid of a woman who had the disease and was pregnant with a microcephalic baby, thus establishing a link between microcephaly and zika infection.
Additionally, scientists also suspect a connection between zika and the Guillain-Barre syndrome, an auto-immune disease which affects the nervous system, after the number of cases of this disease also rose significantly among people who had previously contracted zika.
The news that a disease transmitted by the so-called dengue mosquito, which is an old problem in the country, could cause malformations in babies has prompted the government to set up a stricter campaign for mosquito control.