Breakthroughs Blog: Diagnostics

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. Since 2015, scientists from the Fiocruz Institute in Brazil have been infecting mosquitoes with Wolbachia bacteria in a lab and then releasing them into the wild in trial tests in the hopes of slowing the spread of mosquito-borne diseases like dengue. Wolbachia bacteria—common among insects except the Aedes aegypti mosquito, which transmits dengue, Zika, and chikungunya—works by boosting a mosquito's immune system, making it less likely to contract disease. However, if a mosquito does contract dengue, Wolbachia makes it harder for the virus to grow inside the insect and be transmitted to humans. The hope is that the lab-infected mosquitoes will reproduce with wild mosquitoes, spreading the bacteria through the population. Scientists report “significant reductions” in cases of dengue and chikungunya in neighborhoods near where mosquitoes were released. Tests also show more than 90 percent of mosquitoes in areas where the first infected insects were released more than three years ago have the bacteria. Scientists see this technique as one in a suite of tools to control mosquito populations and halt the spread of disease. The Biomedical Advanced Research and Development Authority (BARDA) awarded the Sabin Vaccine Institute (Sabin) an initial US$20.5 million, with options for an additional $107.5 million, to support development of vaccines against Marburg virus and Sudan Ebola virus. With the initial award, Sabin will conduct development and non-clinical activities with the intent of continuing clinical research through phase 2 trials, which may be supported by the additional funding. The Sudan Ebola vaccine candidate is the first of this virus strain to receive BARDA support and the Marburg vaccine candidate is the second to receive BARDA support. BARDA is also supporting the development of vaccines, therapeutics, and diagnostics against the Ebola virus strain causing the current outbreak in the Democratic Republic of the Congo. For the first time, researchers have developed a rapid diagnostic test that uses a biomarker in saliva to detect the mosquito-borne parasite that causes malaria. The test, which will be marketed as SALVA!, is less invasive than traditional malaria diagnostics, which require a blood sample, and can even detect the disease before people carrying the parasite show symptoms or fall ill. Easy-to-administer at the community level, the test also delivers results in five to twenty minutes without samples being sent to a lab. Global Health Innovative Technology Fund has awarded the test’s developers more than £1 million for field trials and continued development. The World Health Organization has called for more new tools to detect malaria, a disease for which there are more than 200 million cases worldwide each year.

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. On Friday, Kenya became the third African country—following Malawi and Ghana— to introduce the world’s only licensed malaria vaccine. Health authorities are administering the vaccine to young children in rural areas where transmission rates are high. The aim is to reach approximately 360,000 children per year across the three countries in which the vaccine is being rolled out. Although the vaccine only protects about one-third of children who are immunized, those who are vaccinated are likely to have less severe cases of malaria. The vaccine—developed by GlaxoSmithKline, PATH, and partners—is the first and only vaccine to significantly reduce malaria in children, according to the World Health Organization. Malaria kills approximately 435,000 people every year, the majority of whom are children under five years of age in Africa. For the first time, researchers have used CRISPR gene-editing technology to try to treat a person infected with HIV. Scientists in China used CRISPR to engineer human stem cells to mimic a rare form of natural immunity against the HIV virus and transplanted them into a man with HIV and blood cancer. Though many of the cells survived in the man’s body for more than a year without causing detectable side effects, the number of cells was not high enough to significantly reduce the amount of HIV in his blood. While this research was a mixed success, scientists say it serves as proof of concept that CRISPR can be used to edit human stem cells that can be implanted safely in a patient. Researchers at the University of Alberta have developed a user-friendly, affordable, one-step test to diagnose dengue—a mosquito-borne disease that infects nearly 400 million people per year and causes flu-like symptoms. Unlike many traditional diagnostic tests for dengue which, in order to produce a precise diagnosis, require expensive equipment, multiple steps, and advanced training to operate, this test only requires a small blood or plasma sample and a portable tester that produces results in about two hours. As this new dengue test requires cold chemicals, the researchers are now exploring the use of vacuum-drying to create a powder that could withstand the heat in tropical climates where dengue is endemic. Additional research is required for field trials.

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. Researchers at Purdue University have created a device that can rapidly detect the bacterium which causes cholera in water. Unlike traditional tests, which require a well-equipped laboratory and three to five days to process results, this device acts as a portable “cholera detection lab” built around a smartphone. A water sample is placed in a single-use, disposable test kit which uses chemicals that make copies of the toxin gene in cholera bacteria in a process called amplification. If the water becomes more viscous, it signals that harmful bacteria has been identified and the imaging system on the smartphone will capture the results, which can be sent to researchers or charities who can address the water quality issue. The device is currently in early field testing. The nonprofit Sabin Vaccine Institute (Sabin) has acquired the rights from GSK to develop three experimental, single-dose vaccines for Marburg virus, Ebola Sudan, and Ebola Zaire—the strain of the Ebola virus responsible for the yearlong outbreak in the Democratic Republic of the Congo (DRC). Sabin will develop these vaccines in collaboration with the National Institutes of Health Vaccine Research Center, whose scientists originally designed the vaccines which all use the same approach to induce immunity. Though the vaccines have not been tested in phase 3 trials, which would show their efficacy in preventing infection, a phase 2 trial conducted at the end of the West African Ebola outbreak showed that the Ebola Zaire vaccine produced an antibody response in most recipients that lasted up to a year. The largest-ever trial of a preventive Ebola vaccine in Uganda began last week, amid fears of the virus spreading from neighboring DRC. The two-year trial, which will test a two-dose Ebola candidate vaccine developed by Janssen Pharmaceuticals of Johnson & Johnson, will involve 800 participants picked from core health workers and non-core personnel in the Mbarara district, located in the southwest of the country, and will assess the vaccine’s safety and efficacy in inducing an immune response to prevent the disease. The trial will be conducted by both Ugandan and international researchers and is sponsored by the London School of Hygiene and Tropical Medicine. Ebola has killed more than 1,800 people in the DRC during this latest outbreak, which began over a year ago.

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 Wednesday, GlaxoSmithKline (GSK) announced its two-drug HIV regimen, Dovato, was successful in suppressing the virus in patients over a 48-week period at the same level of a previous three-drug treatment in a late-stage trial. The study evaluated the effectiveness of Dovato in adults with HIV-1 virus, the most widespread strain, who switched to the regimen from at least a triple combination containing Gilead’s Vemlidy. GSK’s HIV drugs division, ViiV, noted that adults who used Dovato did not develop any resistance to the treatment. Dovato, a combination of dolutegravir and lamivudine, was approved in the United States in April for newly diagnosed patients. GSK already has a two-drug regimen, Juluca, on the market but only for HIV patients that have received prior treatment.Two experimental Ebola drugs, an antiviral called remdesivir and an antibody treatment called ZMapp, have been found to be effective in laboratory studies in treating the strain of the virus responsible for the deaths of more than 1,600 people in the current outbreak affecting the Democratic Republic of Congo (DRC). According to this new research performed by the Centers for Disease Control and Prevention, in laboratory studies both drugs inhibited the growth of the virus strain in human cells. These two treatments were developed based on strains from previous outbreaks, and this study was the first to test them on the strain causing the current outbreak, which researchers are calling the Ituri strain. According to the latest figures from the World Health Organization (WHO), the Ebola outbreak in DRC has killed 1,630 people with 2,418 total cases—making it the second biggest outbreak of the disease in history.On July 9, WHO published updates to two lists critical for global health: the twenty-first WHO Model List of Essential Medicines and the second WHO Model List of Essential Diagnostics (EDL). These lists help countries prioritize critical health products that should be available, accessible, and affordable in a health system. While the first EDL, developed in 2018, covered a limited number of priority diseases, the second list has expanded to include more noncommunicable and communicable diseases, consisting of 122 test categories. In this editorial piece, Dr. Madhukar Pai, Canada Research Chair of Epidemiology & Global Health at McGill University, explains what’s included in the EDL, what follow up is required by low-and middle-income countries (LMIC) to make the list work, and the LMIC investment required to develop the diagnostic tests and laboratories necessary to deliver on universal health coverage and to better detect outbreaks, antimicrobial resistance, and pandemics.