Breakthroughs Blog: Zika

Interested in more global health innovation news? Every week GHTC scours media reports worldwide to deliver essential global health R&D news and content to your inbox. Sign up now to receive our weekly R&D News Roundup email. Last week, the Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) announced that it is awarding $3 million to Baxiva to support the development of a vaccine that targets the most common serotypes associated with invasive Escherichia coli infections. E. coli is the leading cause of urinary tract infections around the world and a common cause of neonatal sepsis infections, particularly in low- and middle-income countries. The candidate uses new targets that haven’t been used in other vaccines and targets several bacterial strains. The company’s rapid development platform also enables it to quickly design vaccines targeting various types of bacteria.The Coalition for Epidemic Preparedness (CEPI) last week announced a global collaborative effort to carry out epidemiological and computational modelling projects to help strengthen scientific understanding of the Rift Valley fever and its impact across Africa, helping guide the planning of future clinical trials assessing much-needed vaccine candidates for the disease. Despite major Rift Valley fever outbreaks seen in Africa and beyond and global recognition of the need to boost R&D efforts, there are large gaps in our knowledge about the burden and spread of the disease. The two projects, led by institutions in Kenya and Tanzania and supported by global partners, will assess the impact of the disease across Africa, as well as forecast its future burden, providing crucial data for vaccine developers to plan large-scale trials when the virus is widely circulating.A new study from the University of Alabama at Birmingham demonstrates that an antibody designed to target the dengue virus could also block the spread of the Zika virus, an important finding that could inform the development of much-needed treatments for Zika. There are no approved treatments for Zika, a dangerous virus that can pose severe risks to pregnant people and their babies. In a novel preclinical in vivo model, the antibody helped stop the virus from spreading, particularly in vulnerable parts of the body, leading to improved survival rates.

Here in Washington, DC, it’s been an especially buggy summer, with more ticks, mosquitos, and even invasive lanternflies everywhere. In fact, we’re seeing a global rise in mosquito-borne diseases, as rising temperatures, shifting precipitation patterns, and increasing travel and migration bring these critters—and the viruses and parasites they carry—to new places and populations. For example, just last week, a potential case of locally acquired malaria was identified in Washington state, and West Nile virus, a disease transmitted by mosquitoes that was first isolated in Uganda, is now considered endemic in New York state in 2025. Last month, the World Health Organization issued an urgent call for action as chikungunya continues to spread globally again this year, prompting fear of a repeat of the 2004-2005 epidemic. Yellow fever is on the rise too—cases in the Americas during the first few months of 2025 alone more than tripled all cases the region saw last year. 2024 was also the worst year on record for dengue cases. The collective impact of these diseases is striking: globally, mosquito-borne diseases kill more than 1 million people and infect up to 700 million people each year.As conventional vector control methods like insecticide-treated bed nets and indoor residual spraying increasingly face challenges from insecticide resistance and mosquito-borne diseases continue to enter new regions and communities, new and up-and-coming innovations, including in diagnostics, mosquito population modification, and vaccines, will be key to helping minimize the spread of these deadly and debilitating diseases. New diagnostics can help ensure patients start treatment earlierWhile effective tools exist to diagnose mosquito-borne diseases, next-generation tools now in the pipeline could help people receive an accurate diagnosis faster, earlier, at a lower cost, and closer to their home, as well as distinguish between different mosquito-borne infections with similar symptoms. These promising breakthroughs could improve detection and care, particularly in rural and remote areas worldwide.A research team at Institut Pasteur is developing a new rapid diagnostic that can detect the presence of the Plasmodium vivax malaria parasite shortly after the initial mosquito bite—before symptoms arise—, helping patients receive appropriate treatment more quickly. Another team has developed a diagnostic device that uses strips of paper, which could serve as a more affordable, portable diagnostic alternative for detecting malaria infection in asymptomatic people in just 30 minutes.Beyond malaria, a team of Brazilian researchers has developed a novel test that can rapidly identify exposure to all four serotypes of dengue virus, as well as the Zika virus, making it perfectly suitable for regions like Brazil that are endemic to both viruses, where the similarity between symptoms can make it hard to diagnose or assess immunity in patients. This test could also help health care providers and public health workers better pinpoint where treatment and preventive measures need to be implemented.Another new tool developed by scientists at the National Institute of Allergy and Infectious Diseases could also aid surveillance and response. It uses blood samples to identify people who have been bitten by Aedes mosquitoes, which can spread diseases like dengue, Zika, and chikungunya, to identify geographic hot spots for the mosquitoes and monitor exposure in people, helping improve targeted public health interventions. New and innovative tests like these can help identify and minimize the spread of mosquito-borne diseases by connecting people to treatment earlier, as well as informing public health efforts to implement larger-scale vector control measures. Modifying mosquitoes can make it harder for insects to spread diseaseAnother approach to curb mosquito-borne diseases is to directly control the mosquito population by targeting the insect’s ability to transmit viruses or parasites to people through genetic modification or other means. One method establishes a bacterium called Wolbachia, which is commonly found in insects, in an Aedes aegypti mosquito population, blocking viruses like dengue, chikungunya, and Zika from growing inside the insects' bodies. This approach has helped protect more than 13.3 million people as of December 2024. Another research team has found a way to genetically engineer Anopheles stephensi mosquitoes by inserting a gene, which naturally occurs in some mosquitoes, that makes them poor hosts for malaria parasites.Scientists are also exploring approaches that involve inhibiting the reproduction of mosquitoes to reduce population size, and thus, the spread of disease. A Spanish research team is releasing thousands of sterilized tiger mosquitoes, one of the species whose females transmit dengue, to reduce the spread of dengue and other vector-borne diseases. Similar sterilization techniques have been previously used to address other disease vectors, but the Spanish lab is pioneering its use on the tiger mosquito.In an altogether different and novel approach, scientists in the Netherlands are looking into a way to modify mosquitoes so their bite can deliver a vaccine for malaria to humans, with continuous exposure through multiple bites prolonging immunity levels.While some of these methods of targeting mosquito populations have proven effective already and new methods could offer even more precise mechanisms for vector control, the long-term implications on the ecosystem warrant further consideration, so science must move forward cautiously. New vaccines could be game changers, but research has stalled for some diseasesExperts believe that vaccines are essential for drastically reducing the incidence of mosquito-borne diseases, and when used in combination with other prevention methods, could help turn the tide against this growing threat. The world’s first malaria vaccine was approved in 2021, closely followed by a second vaccine in 2023, both of which have already had a huge impact, with 24 million doses delivered across 20 countries. Ongoing research aims to resolve some of the limitations of these first-generation vaccines. One innovative malaria vaccine candidate that is undergoing a clinical trial uses genetically engineered parasites that cannot cause disease but are potent enough to trigger a strong immune response. Preclinical data found that the vaccine could potentially offer higher efficacy at lower doses than current vaccines.The first vaccine for dengue, which could only be used among people who had previous infections, was approved in 2019, but its production is being phased out due to limited use. It was trailed by additional vaccines, including the Qdenga vaccine, which targets all four types of the dengue virus and is safe for use in individuals with and without prior infection. However, it does not provide equal protection against all dengue subtypes and has not been studied enough in people over 16 years old. Researchers in Brazil have developed a single-dose vaccine targeting all dengue subtypes that demonstrated high efficacy in people across ages in recent Phase 3 trials. Its single dose would hopefully also make it easier to administer and scale up production.While these vaccines hold tremendous promise, there are still gaps in the pipeline and a lack of availability of vaccines for certain mosquito-borne diseases. There are no human vaccines for West Nile virus, even though safe and highly effective West Nile vaccines for horses have been around for decades, with research and development efforts in the United States hindered by the sporadic and unpredictable nature of outbreaks. Zika vaccine research has also stalled since the 2015-2016 outbreak, attention dwindling along with cases as people forget the frightening and unexpected nature of the last rise in cases.With trends like climate change, globalization, and migration showing no signs of slowing down, the world’s deadliest animal and the diseases it carries are only going to become a bigger risk to human health. We’ve made tremendous progress against these diseases, but further innovations will better prepare us to take on a buggier future.

Interested in more global health innovation news? Every week GHTC scours media reports worldwide to deliver essential global health R&D news and content to your inbox. Sign up now to receive our weekly R&D News Roundup email. A team of Brazilian researchers has developed a simple test that can detect exposure to any of the four strains of dengue virus, as well as the Zika virus, as dengue cases continue to rise to a concerning degree in the region. The test was first validated with blood samples from mice experimentally infected with the viruses and then with hundreds of blood samples donated by people during the 2015-2017 Brazilian Zika epidemic. It uses technology that can be easily adapted for use in automated systems and rapid point-of-care tests and could serve as a key tool in the case of a Zika outbreak, allowing health care providers to test the immunity of at-risk groups while accounting for the possibility of cross-reactivity with antibodies produced after infection by dengue.Last week, IAVI and Biofabri announced that the first doses of tuberculosis (TB) vaccine candidate MTBVAC have been administered in a critical large-scale Phase 2b trial testing the safety and efficacy of MTBVAC to prevent active TB lung disease in adolescents and adults. While there is a vaccine for TB, it is more than 100 years old and has limited efficacy in preventing pulmonary TB, the most common form in adults. A new vaccine could be a game changer in the global fight against this leading infectious disease. MTBVAC is also a single-shot vaccine, making it easier to administer in low-resource and remote settings, and the partners developing it are committed to ensuring that, if proven successful in further trials, there will be a sufficient, affordable supply in the places where it is most needed.The Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) last week announced a $2 million award to Immunethep to develop a vaccine against invasive strains of Escherichia coli. The funding will support work on a conjugate peptide-based vaccine candidate designed to induce immunity to E coli, which can cause serious, life-threatening infections that are becoming harder to treat with the rising prevalence of antimicrobial resistance. There are currently no vaccines for E coli. The candidate has demonstrated efficacy against E coli, as well as four other priority bacterial pathogens in animal models, and, if it continues to prove successful, could be a key tool for preventing serious bacterial infections in vulnerable populations.

Interested in more global health innovation news? Every week GHTC scours media reports worldwide to deliver essential global health R&D news and content to your inbox. Sign up now to receive our weekly R&D News Roundup email. A new, first-of-its-kind trial will assess the safety and immunogenicity of Bavarian Nordic’s MVA-BN mpox vaccine in pregnant and breastfeeding women and infants under two years old, two populations at risk of severe complications from mpox but not currently eligible for vaccination. MVA-BN is the only vaccine for mpox prequalified by the World Health Organization and is currently approved for healthy adults and adolescents, but additional data from this trial could help expand access for additional key populations amid the ongoing mpox outbreak. The trial, which will start early next year, is jointly funded by the Coalition for Epidemic Preparedness Innovations (CEPI) and Global Health EDCTP3.Researchers from the University of Glasgow have developed a new drug that could help combat the spread of treatment-resistant malaria, as the disease continues to kill more than 600,000 people every year and Plasmodium falciparum, a mosquito vector that spreads malaria, grows increasingly resistant to artemisinin, the frontline malaria treatment. The drug, adapted from a cancer treatment approach, works by permanently disabling a protein that P. falciparum uses to duplicate itself in humans. The researchers behind the drug think it could be more effective than current drugs at all stages of malaria infection, potentially with only one dose.A research team from the University of California, Santa Barbara has found a way to potentially reduce the spread of mosquito-borne diseases by disrupting male mosquitoes’ ability to hear, which is essential for them to mate and breed. Male mosquitoes rely on the sound of female mosquitoes’ wingbeats in order to find and mate with them. By altering a genetic pathway that male mosquitoes use for hearing, the researchers were able to stop them mating entirely, preventing female mosquitoes, the ones that spread diseases to humans, from having babies and reducing overall mosquito populations. Specifically, the researchers studied Aedes aegypti mosquitoes, which spread diseases including dengue, yellow fever, and Zika.