Brazilian soldiers display an almost biblical urgency as they rush from door to door in Recife — the northeastern coastal city that is the frontline of the fight against the Zika virus.
They call through slats, gates, and letterboxes, urging people to empty stagnant water and prevent disease-carrying mosquitos from breeding. When doors open they search for possible infestations and, if they find any, put down orange larvacide granules, which attract the feeding larvae and then poison them.
It is a thankless and seemingly never-ending task that unfolds amid an often ambivalent public.
"People have the knowledge, they are informed through the TV. It's just that they don't always put measures in place," said Lieutenant Yago Douglas da Silva Fortaleza, who is responsible for one of the units inspecting a poor community in Recife. "They think it's a problem for somewhere else."
Brazil's crusade against the mosquito-borne Zika virus stems from evidence suggesting a link between the Dengue-like disease — that is typically mild and often asymptomatic — and a sudden hike in the number of babies born in the country with abnormally small heads.
The possible link, which was first noticed last August, has not been scientifically proved, but the World Health Organization said on Monday that the evidence is strong enough to warrant declaring Zika to be a global emergency.
Brazil, where an estimated 1.5 million have been infected with Zika since the virus was first detected in the country eight months ago, had already announced the deployment of 200,000 troops to aid health workers combat the mosquito.
This week president Dilma Rousseff signed off on additional provisional measures that allow any public agent in search of mosquitos – including soldiers - to forcibly enter properties where the owner is absent, or the building has been abandoned.
"In the situation of imminent danger to public health through the presence of a mosquito that transmits Dengue Fever, Chikungunya, and Zika, the highest authority of the National Health System across federal, state, county and municipal levels is authorized to establish and implement the necessary measures to control the diseases caused by these viruses," the federal gazette said.
The extra powers follow reports that some households in Recife have been refusing health agents entry to their homes. The reticence is said to stem from a rash or burglaries in which conmen have posed as inspectors.
The authorities also have to battle the doubts of those who want to cooperate, but are concerned that this will not be enough to contain the virus that has already spread well beyond Brazil to at least 23 other countries.
"We're worried because we take care of our home but there are neighbors who don't," said Glaucia Perreira Ramos, 30, who stayed home to wait for inspectors in her humble Roda de Fogo community in Recife where sanitation conditions are poor.
On Monday night, key government officials met with the president to discuss public engagement.
"Of course we are doing our part by mobilising where needed," Jacque Wagner, the president's chief of staff, told reporters after the meeting. "But the mosquito lives on the street, on the corner, and in a water tank that has a crack."
The Brazilian authorities have said that the military campaign is building up to what it calls a "Day of Clarification" on February 13, aimed at raising awareness. The day will involve a concentrated effort of all public institutions to promote the fight against the mosquito, including a special hotline for suspected infestations.
"The only way to fight the mosquito is by spreading awareness and that is a task not only for public services," Wagner said. "The only vaccine we have now is the awareness and citizen mobilisation of everyone."
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