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Anopheles malaria mosquitoes in Africa and Latin America are evolving in response to human activity, studies in both continents have found. Anopheles gambiae, the most significant malaria vector in Africa, is developing increasing resistance to pyrethroid insecticides, a study published in Nature Scientific Reports this month shows. Synthetic pyrethroids are the most commonly used insecticide for controlling malaria mosquitoes worldwide. The team of researchers from Kenya, Ghana and the US [...]

Mammal loss is accelerating across Latin America, threatening the delicate ecosystem balance that ultimately provides communities with food, shelter and livelihoods, new research warns. The extinction or decline in the populations of mammals — particularly the largest of these animals — can have far-reaching consequences for the natural processes of ecosystems, such as seed dispersal, pollination and even oxygen production, a study published in Ecosystem [...]

Remote light sensing technology has revealed that the fragmentation of the Amazon rainforest contributed one-third of deforestation carbon emissions in the region between 2001 and 2015. Deforestation fragments forests, creating artificial edges and altering forest ecologies — known as ‘edge effects’.  “Forest edges are more exposed to the sun, which dries vegetation out and raises local temperatures,” Celso Silva Junior, lead author of a [...]

In Brazil’s coronavirus-ravaged north, up to 66 per cent of people living in Manaus have contracted COVID-19, according to new research that aims to shed light on herd immunity. Manaus, the capital of Amazonas state, has recorded about 51,000 cases of COVID-19 and more than 2,500 deaths from its population of less than two million. Many countries are yet to have recorded 50,000 cases. The threshold for herd immunity — a “fundamental epidemiological parameter” — [...]

Water will become scarcer and more degraded as demand in Brazil increases up to 25 per cent over the next 30 years, warn scientists, as they urge governments to improve sanitation and environmental protections. Loss of native plant cover is the main threat to water sources across Brazil, according to a study led by the University of São Paulo. Just 26 per cent of original vegetation remains in the country’s Atlantic Forest region, which is home to 65 per cent of the [...]

Waste pickers exposed to discarded electronics, aluminium and metal cans have up to four times higher levels of the toxic heavy metal cadmium in their blood than the wider population, a study has found. Researchers in Brazil found that salvagers and workers at recycling facilities — known as waste pickers — who previously worked in another occupation had lower cadmium levels, suggesting that length of exposure and heavy metal concentration levels are linked. Scientists compared [...]

Brazilian scientists have collected more than 90,000 signatures in less than a week against a bill that would slash the science and research budget in the state of São Paulo, which produces about half of Brazil’s scientific output. Science across the country, not just research in São Paulo, will be harmed if the bill is approved, the scientific community says. They say institutions that contribute to public health and knowledge development should be allowed to continue [...]

Brazil’s community health workers serve 75 per cent of Brazil’s 210 million residents, yet just nine per cent have been given personal protective equipment or infection control training, say global health experts. The 286,000 community health workers (CHWs) “are the bedrock of Brazil’s Unified Health System [SUS]”, says Gabriela Lotta, a professor at the think tank and education institution, the Getulio Vargas Foundation. However, Brazil’s community health [...]

Domestic and international air travel helped spread the novel coronavirus in Brazil, a study has found, as tourism bodies push for global travel to resume amid infection resurgences in some countries. The collapse of global tourism during the COVID-19 pandemic has cost the industry US$320 billion, according to the UN World Tourism Organization (UNWTO). The drive to restart the industry has already begun: UNWTO analysis shows that 40 per cent of global destinations have eased [...]