Brazil has declared an end to its public health emergency over the Zika virus, but doctors have warned that victims of the disease must not be forgotten.

It was not considered a major health threat until the 2015 outbreak revealed it can cause birth defects.

Thousands of babies have been born with microcephaly, leaving them with reduced head size and symptoms including stunted development, seizures and delayed speech skills.

“The end of the emergency doesn't mean the end of surveillance or assistance” to affected families, said Adeilson Cavalcante, the secretary for surveillance at Brazil's health ministry.

“The health ministry and other organizations involved in this area will maintain a policy of fighting Zika, dengue and chikungunya.”

All three diseases are carried by the Aedes aegypti mosquito, which Brazil has been battling to eradicate to stop the spread of Zika.

The Zika virus - in pictures Show all 5 1 /5 The Zika virus - in pictures The Zika virus - in pictures A three-month-old, who has microcephaly, in Recife, Brazil. A rise in microcephaly cases is thought to have been caused by the spread of the Zika virus in affected countries Getty Images The Zika virus - in pictures A mother holds her baby who has microcephaly Getty Images The Zika virus - in pictures A five-month-old baby, who has microcephaly, in Recife, Brazil Getty Images The Zika virus - in pictures A pediatric infectologist examines a two-month-old baby, who has microcephaly, in Recife, Brazil Getty Images The Zika virus - in pictures A baby affected with microcephaly

From January through to mid-April, the health ministry recorded 95 per cent fewer cases than during the same period last year, with the incidence of microcephaly also falling.

But the World Health Organisation (WHO) has warned that Zika is “here to stay” despite the decline in cases, and that continued efforts are needed to fight the disease.

Adriana Melo, the Brazilian doctor who raised alarm early in the outbreak about a link between Zika and birth defects, said the official lifting of the public health emergency had been expected.

“The important thing now is that we don't forget the victims,” she added.

Brazil was at the epicentre of the public health emergency declared in 2015, which caused a global alert to be issued by the WHO as cases were found around the world, arriving in the US and Europe.

The outbreak came just as Brazil, was preparing to host the 2016 Olympics, fuelling concerns the Games could help spread the virus.

At least one athlete, a Spanish wind surfer, said she contracted Zika during training in the country.

Travel warnings issued by governments including the UK caused travellers, particularly pregnant women most at risk, to cancel trips to affected countries, while revelations Zika could be sexually transmitted heightened concern.

Zika, first recorded in humans in the 1950s, is transmitted by the Aedes aegypti mosquito and spread from Uganda through Africa, Asia, the Pacific and onwards to South America.

The WHO lifted its own international emergency in November, while saying the virus remained a threat.