Malaria remains a global health challenge, with 263 million cases and 597,000 deaths reported in 2023. Current vector control methods, such as long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), have become less effective due to insecticide resistance and behavioral adaptations in mosquitoes to bite outdoors and during dusk or dawn, when people are not protected by these measures. This underscores the urgent need for innovative solutions to combat malaria.

Ivermectin for malaria: A novel strategy

Ivermectin, a drug traditionally used to treat neglected tropical diseases like onchocerciasis, which causes river blindness, and lymphatic filariasis, which causes elephantiasis, has been shown to reduce malaria transmission by killing the mosquitoes that feed on treated individuals. Given the rising resistance to conventional insecticides, ivermectin could offer an effective new approach totackle malaria transmission, especially in regions where traditional methods have become less effective.

The Unitaid-funded BOHEMIA project(Broad One Health Endectocide-based Malaria Intervention in Africa) conducted two Mass Drug Administration (MDA) trials in the high-burden malaria regions: Kwale County (Kenya) and Mopeia district (Mozambique). The trials assessed the safety and efficacy of a single monthly dose of ivermectin (400 mcg/kg) given for three consecutive months at the start of the rainy season in reducing malaria transmission. In Kenya, the intervention targeted children aged 5-15, while in Mozambique it focused on children under five.

Malaria reduction in Kenya

In Kwale County, Kenya, children who received ivermectin experienced a 26% reduction in malaria infection incidence compared to those who received albendazole, the control drug used in the study. The trial involved over 20,000 participants and more than 56,000 treatments, demonstrating that ivermectin significantly reduced malaria infection rates — particularly among children living further from cluster borders or in areas where drug distribution was more efficient. Moreover, the safety profile of ivermectin was favorable, with no severe drug-related adverse events and only mild, transient side effects already seen with ivermectin in campaigns against neglected tropical diseases.

“We are thrilled with these results,” says Carlos Chaccour, co-principal investigator of the BOHEMIA project and ISGlobal researcher at the time of the study. “Ivermectin has shown great promise in reducing malaria transmission and could complement existing control measures. With continued research, ivermectin MDA could become an effective tool for malaria control and even contribute to elimination efforts,” Chaccour, who is now a researcher at the Navarra Centre for International Development at the University of Navarra, adds.

“These results align with the World Health Organization’s (WHO) criteria for new vector control tools,” states Joseph Mwangangi, from the KEMRI-Wellcome Trust Research Programme. “The findings suggest that ivermectin MDA could be a valuable complementary strategy for malaria control, particularly in areas where mosquito resistance to insecticides is a growing concern,” adds Marta Maia, BOHEMIA’s lead entomologist from the University of Oxford.

Lessons from the Mozambique trial

In contrast, the implementation of the Mozambique trial in the rural district of Mopeia faced severe disruptions due to Cyclone Gombe (2022) and a subsequent cholera outbreak, which significantly disrupted operations. “One of the most important lessons we learned from the trial in Mopeia is that strong community engagement is essential,” states Francisco Saúte, director of the Manhiça Health Research Centre (CISM). “Building trust with local communities and fostering close collaboration with the Health Ministry, National Malaria Control Program, and local authorities was key to ensuring acceptance of the ivermectin MDA.”

Expanding the Impact Beyond Malaria

In addition to reducing malaria transmission, ivermectin MDA offers significant collateral benefits. The BOHEMIA team found an important reduction in the prevalence of skin infestations such as scabies and head lice in the ivermectin group in Mozambique, and the community reported a major reduction in bed bugs in Kenya. These effects are particularly valuable when ivermectin is integrated into existing delivery systems, maximizing its impact on public health.

Shaping the future of malaria prevention

The study is part of a larger global effort to assess ivermectin’s potential in malaria control. The findings have been reviewed by the WHO vector control advisory group, which concluded that the study had demonstrated impact and recommended further studies. Findings were also shared with national health authorities as they evaluate the potential inclusion of ivermectin in malaria control programs.

“This research has the potential to shape the future of malaria prevention, particularly in endemic areas where existing tools are failing,” concludes Regina Rabinovich, BOHEMIA PI and Director of ISGlobal’s Malaria Elimination Initiative. “With its novel mechanism of action and proven safety profile, ivermectin could offer a new approach using a well-known, safe drug that can add to the effect of other mosquito control tools available today.”

In findings recently published in Environmental Research Letters, the team reported that the level of corn crop decline would vary, depending on the scale of the conflict. A regional nuclear war, which would send about 5.5 tons of soot into the atmosphere, could reduce world-wide annual corn production by 7%. A large-scale global war, injecting 165 tons of soot into the atmosphere, could lead to an 80% drop in annual corn yields. In all, the study simulated six nuclear war scenarios with varying soot injections.

Because of the crop’s global significance, the researchers chose to model corn’s collapse in a nuclear winter to represent the expected fate of agriculture overall, according to study first author Yuning Shi, associate research professor in Penn State’s Department of Plant Science. He noted that an 80% drop in global crop production would have catastrophic consequences, leading to a widespread global food crisis. Even a 7% drop in global crop production would have a severe impact on the global food system and economy, likely resulting in increased food insecurity and hunger.

The simulations were possible thanks to the Cycles agroecosystem model, created a few years ago by scientists in Penn State’s College of Agricultural Sciences, including lead developer Armen Kemanian, professor of production systems and modeling and corresponding author on this study. Using high-performance computing and considering atmospheric conditions, Cycles enables large-scale, high-resolution, multi-year simulations of crop growth by meticulously tracking the carbon and nitrogen cycles within the soil-plant-atmosphere system.

“We simulated corn production in 38,572 locations under the six nuclear war scenarios of increasing severity — with soot injections ranging from 5 to 165 tons,” Shi said. “This investigation advances our understanding of global agricultural resilience and adaptation in response to catastrophic climatic disruptions.”

In addition to considering the effects of massive amounts of soot in the atmosphere, the researchers modeled the increase in UV-B radiation — a type of ultraviolet radiation that can lead to DNA damage, oxidative stress and reduced photosynthesis in plants — that would reach Earth’s surface in a nuclear winter that could further limit agriculture.

Shi said he believes that this was the first study to estimate the extent of UV-B radiation damage to agriculture after nuclear explosions, which the researchers predicted would peak six to eight years after a global war. They estimated this could further cut corn production by an additional 7%, for a total worst-case scenario of an 87% drop in corn production.

Ozone high in Earth’s atmosphere effectively absorbs the bulk of UV radiation the planet receives from the sun, but nuclear war would dismantle this ability, Shi explained.

“The blast and fireball of atomic explosions produce nitrogen oxides in the stratosphere,” he said. “The presence of both nitrogen oxides and heating from absorptive soot could rapidly destroy ozone, increasing UV-B radiation levels at the Earth’s surface. This would damage plant tissue and further limit global food production.”

While the predictions point to potentially catastrophic drops in the production of corn varieties currently grown, Shi said, switching to crop varieties that can grow under cooler conditions in shorter growing seasons could boost global crop production by 10% compared to no adaptation. However, seed availability for these crops could become a serious problem — a “bottleneck to adaptation,” the researchers said.

Their proposed solution is to prepare “agricultural resilience kits” ahead of any nuclear disaster, containing region- and climate-specific seeds for crop varieties that can grow under cooler conditions with shorter growing seasons to survive lower temperatures.

“These kits would help sustain food production during the unstable years following a nuclear war, while supply chains and infrastructure recover,” Kemanian said. “The agricultural resilience kits concept can be expanded to other disasters — when catastrophes of these magnitude strike, resilience is of the essence.”

Shi noted that while proactive, internationally coordinated planning for such kits is unlikely, simply increasing awareness could help lead to better preparedness. “If we want to survive, we must be prepared, even for unthinkable consequences,” he said.

Kemanian said he sees value in the research beyond human-caused calamity.

“Recall that catastrophes of this nature can happen not just because of nuclear war, but due to, for example, violent volcanic eruptions,” he said. “One may think that studies of this nature are just navel gazing, but they force us to realize the fragility of the biosphere — the totality of all living things and how they interact with one another and the environment.”

Contributing to the research at Penn State were Felipe Montes, associate research professor of cropping systems modeling; Francesco Di Gioia, associate professor of vegetable crop science; and Charles Anderson, professor of biology and principal investigator of the project funding this work; as well as Charles Bardeen, with the Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, Colorado; and Yolanda Gil, Deborah Khider and Varun Ratnakar, all with the Information Sciences Institute, University of Southern California.

This research was supported by Open Philanthropy, the Defense Advanced Research Projects Agency, the U.S. Department of Agriculture National Institute of Food and Agriculture, the U.S. National Science Foundation and the Future of Life Institute.

Despite the growing popularity of bio-based plastics, plastic pollution remains one of the world’s most pressing environmental issues. According to the OECD’s Global Plastics Outlook (2022), about 353 million metric tons of plastic waste were produced globally in 2019, with nearly 1.7 million metric tons flowing directly into aquatic ecosystems. Much of this waste becomes trapped in large rotating ocean currents, known as gyres, forming the infamous “garbage patches” found in the Pacific, Atlantic, and Indian Oceans.

To tackle this, researchers have been searching for plastics that can be degraded more reliably in deep-sea environments. One promising candidate is poly(d-lactate-co-3-hydroxybutyrate) or LAHB, a lactate-based polyester biosynthesized using engineered Escherichia coli. So far, LAHB has shown strong potential as a biodegradable polymer that breaks down in river water and shallow seawater.

Now, in a study made available online on July 1, 2025, and published in Volume 240 of the journal Polymer Degradation and Stability on October 1, 2025, researchers from Japan have shown for the first time that LAHB can also get biodegraded under deep-sea conditions, where low temperatures, high pressure, and too limited nutrients make breakdown of plastic extremely difficult. The study was led by Professor Seiichi Taguchi at the Institute for Aqua Regeneration, Shinshu University, Japan, together with Dr. Shun’ichi Ishii from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Japan and Professor Ken-ichi Kasuya from Gunma University Center for Food Science and Wellness, Japan.

“Our study demonstrates for the first time that LAHB, a microbial lactate-based polyester, undergoes active biodegradation and complete mineralization even on the deep-sea floor, where conventional PLA remains completely non-degradable,” explains Prof. Taguchi.

The research team submerged two types of LAHB films — one containing about 6% lactic acid (P6LAHB) and another with 13% lactic acid (P13LAHB) — alongside a conventional PLA film for comparison. The samples were submerged at a depth of 855 meters near Hatsushima Island, where deep-sea conditions, cold temperatures (3.6 °C), high salinity, and low dissolved oxygen levels make it hard for microbes to degrade plastic.

After 7 and 13 months of immersion, the LAHB films revealed clear signs of biodegradation under deep-sea conditions. The P13LAHB film lost 30.9% of its weight after 7 months and over 82% after 13 months. The P6LAHB film showed similar trends. By contrast, the PLA film showed no measurable weight loss or visible degradation during the same period, underscoring its resistance to microbial degradation. The surfaces of the LAHB films had developed cracks and were covered by biofilms made up of oval- and rod-shaped microbes, indicating that deep-sea microorganisms were colonizing and decomposing the LAHB plastic. The PLA film, however, remained completely free of biofilm.

To understand how the plastic decomposes, the researchers analyzed the plastisphere, the microbial community that formed on the plastic’s surface. They found that different microbial groups played distinct roles. Dominant Gammaproteobacterial genera, including Colwellia, Pseudoteredinibacter, Agarilytica, and UBA7957, produced specialized enzymes known as extracellular poly[3-hydroxybutyrate (3HB)] depolymerases. These enzymes break down long polymer chains into smaller fragments like dimers and trimers. Certain species, such as UBA7959, also produce oligomer hydrolases (like PhaZ2) that further cleave these fragments, splitting 3HB-3HB or 3HB-LA dimers into their monomers.

Once the polymers are broken down into these simpler building blocks, other microbes, including various Alpha-proteobacteria and Desulfobacterota, continue the process by consuming the monomers like 3HB and lactate. Working together, these microbial communities ultimately convert the plastic into carbon dioxide, water, and other harmless compounds that ideally return to the marine ecosystem.

The findings of this study fill a critical gap in our understanding of how bio-based plastics degrade in remote marine environments. Its proven biodegradability makes it a promising option for creating safer, more biodegradable materials.

“This research addresses one of the most critical limitations of current bioplastics — their lack of biodegradability in marine environments. By showing that LAHB can decompose and mineralize even in deep-sea conditions, the study provides a pathway for safer alternatives to conventional plastics and supports the transition to a circular bioeconomy,” says Prof. Taguchi.