The rapid spread of the Zika virus across Brazil is giving local authorities a headache as the country is gearing up for the annual carnival celebrations. In the past few weeks, the country's health authorities have increased preventive measures and awareness campaigns in the hope of reducing the disease's impact in major tourist cities such as Rio de Janeiro.

During rehearsals for street bands' parades and samba performances, flyers are distributed advising citizens to empty disused flower vases or buckets in case the stagnant water there becomes a breeding ground for Aedes aegypti mosquito, carrier of the Zika virus.

Healthcare agents have been going door-to-door in the city in search of areas where Aedes larvae might be. There are more than 3,000 people helping with this task, according to Rio's municipal administration.