On a hill overlooking a middle-class neighbourhood and a hospital lies one of São Paulo’s slums – home to about 300 families trying to eke out a living in the largest city in Brazil. Here in Boi Malhado, ramshackle dwellings built with planks of wood and corrugated iron are perched precariously on the hillside. Only recently, one house belonging to a mother and her newborn baby collapsed. Both survived but the remains are there for everyone to see.

Children run up and down narrow passageways between laundry lines and live electric wires; sewers are a hole in the ground covered by a piece of wood; and water access is sporadic – it’s common for the community to go without for days. “Our government is very unfair,” says resident Mariangela Ferreira, 35. “We pay our taxes and we don’t even have the basics.”

Paraisópolis, the largest favela in São Paulo (top); around 300 families live in this particular area of the Boi Malhado favela (bottom left); the remains of a house which collapsed (bottom right)

Inhabitants face all manner of health problems, including HIV. It is this that has brought Sandra Santos, a healthcare professional who specialises in educating young people about the virus, here on a Saturday afternoon. Santos, who works at Emilio Ribas hospital is convinced that it’s areas like this where she must work.

But it’s challenging. The poverty is breathtaking and Santos had to go through an intermediary to ask the drug dealers that rule this area to allow her into the slum. “Healthcare professionals won’t enter because they’re too scared,” she says. “But these are the people who we can’t reach and who need our help.”

Sandra Santos (right) talks to residents of Boi Malhado about HIV

In the past hour, she has spoken to a 20-year-old mother who is living with a diagnosis of HIV. The new mother is taking antiretroviral drugs – she started when she found out she was pregnant – but Santos fears for the future. “If [health services] don’t give her the support she needs, she will lose motivation and not take her medication.”

The number of young people with HIV in Brazil is on the rise. Figures from 2019 show that from 2007 to June 2019, 300,496 cases of HIV were reported in Brazil. The majority (52.7%) were found among those aged 20-34. While rates among the white population are falling, more black people are becoming infected. In São Paulo, young men account for the most accentuated spread of the epidemic. In the 10 years up until 2018, male 15- to 19-year-olds, 20- to 24-year-olds and 25- to 29-year-olds showed an increase in detection of 3.8 times, 2.9 and 2.3 times respectively.

A pregnant resident of Boi Malhado stands in her house (top); views in and out of the favela (bottom left and right)

Santos’s work has never been more important. Traditionally her role has been to welcome young people who contracted HIV from their mothers to the hospital, and work with other healthcare professionals to educate them around the importance of taking their medication, as well as helping them to deal with prejudice and stigma in society.

Now she is focusing on prevention. She works with a team of young people with the virus to give lectures in schools and youth centres about what living with HIV is like, and how to avoid getting it in the first place.

Renata Ferreira, 21, is a patient at Emilio Ribas and recently helped to set up an organisation that supports other young people with HIV. She also goes out with Santos and others to talk about her life with the virus.

Santos with three teenage residents of Boi Malhado

She was the only one of three siblings to contract HIV from her mother and now lives in Paraisópolis, one of the largest favelas in Brazil, with her adoptive parents. She takes antiretrovirals and is undetectable – she cannot pass on HIV through sex and can have children without giving them the virus. “No one knows about HIV around here. We know it exists but that’s it,” says Ferreira. “We are taught very little about sex and prevention. Even doctors don’t know much.” At her local health centre, she has found herself explaining aspects of living with HIV to doctors.

Life hasn’t always been easy for Ferreira. “Until the age of 14 I thought I was going to die,” she says. “I didn’t have other people with HIV in my life.” There were times when she gave up taking her medication and struggled with stigma at school. Along with Santos and her friend and colleague Thiago Martins, who also lives with HIV, Ferreira has seen lots of people die. Santos remembers one year when 17 people she was working with died. “We’d go from a funeral to a birthday party. It was very hard,” she says.

Thiago Martins and Renata Ferreira in the grounds of Emilio Ribas hospital where they receive treatment for HIV

Back in Boi Malhado, Maria dos Anjos, a community leader, sits at a table with Santos talking about ways they can work together. “It’s so important to talk about HIV. And first we must talk about prevention,” says Anjos. “I know 11- and 12-year-old girls who have to prostitute themselves to survive. We have a problem with sexually transmitted infections and pregnancy because children don’t receive any sex education.”

The future may be fraught with challenges and Santos and her colleagues have to work in a difficult political climate: the president of Brazil, Jair Bolsonaro, recently labelled people with HIV “an expense for everyone”. But today has been productive and, at least on the ground, there is hope and appetite for change.