In the midst of the greatest climate tragedy in the history of Rio Grande do Sul, the affected population, which still suffers from floods and the lack of basic services, faces another enemy: the high risk of transmitting diseases, such as leptospirosis. The disease is transmitted through direct contact with the urine of rats infected with the bacteria. Leptospira or through contaminated water and mud.
In areas at risk of flooding, the incidence of the disease can increase more than ten times, says the Butantan Institute citing the World Health Organization (WHO). Rodent control is also important to prevent the spread of infection. In Porto Alegre, residents reported an infestation of rats and cockroaches after the floods. In 2023, Brazil recorded 3,128 cases of leptospirosis, and the South of the country had the highest incidence: 1,221 – there were 70 deaths in the region.
Current tests are a major obstacle to diagnosis, as they only detect the infection a week after the onset of symptoms – when complications and risk of death already exist. Furthermore, the disease can manifest itself up to 30 days after contact with contaminated mud or water.
Concerned, the Brazilian Society of Infectious Diseases (SBI) released a note recommending the use of specific antibiotics as prevention for people exposed to flood waters for a prolonged period, rescue teams and volunteers, a group considered at high risk.
According to the Ministry of Health, anyone infected with Leptospira may present with a sudden fever above 38°C – lasting 7 to 14 days –, chills, headache, muscle pain (especially in the calf), nausea, vomiting and lack of appetite in the first week after contact with infected water. The most serious conditions occur in 15% of cases, starting in the second week. Mortality, around 10%, can reach 50%.
Prevention is urgent in the face of chaos. Until yesterday, according to the Civil Defense of Rio Grande do Sul, 397 municipalities had been devastated by floods – 79.88% of the 497. The floods affected 1.4 million people and have left almost a hundred dead and more than 130 missing. If preventive measures are not adopted immediately, the suffering of the population of Rio Grande do Sul could become even greater and last for an even longer period.
