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One-third of the world’s population—more than 2 billion people—has latent tuberculosis (TB) and each year, 9.6 million people develop active TB. However, a team of scientists have identified 16 genes, referred to as a “risk signature,” that can predict which cases are most likely to progress to active TB. In two studies enrolling more than 10,000 participants across South Africa and Gambia, researchers collected and analyzed blood samples to detect the presence of the risk signature. The genes predicted cases of active TB with sensitive and specificity rates of 66.1 percent and 80.6 percent: in other words, two-thirds of the patients with the genetic risk signature developed active TB during the study, compared to only one-fifth of those without the risk signature. TB is the world’s leading infectious disease killer, resulting in 1.5 million deaths in 2014. However, the study suggests that this risk signature could be used to predict cases of active TB up to 18 months in advance, and treating latent TB can reduce the risk of developing the disease by 90 percent. A new tool to easily insert intrauterine devices (IUDs)—long-acting contraceptive devices that can remain in the uterus for up to twelve years—could make the devices more accessible in low-resource settings. IUDs contain either copper, which is toxic to sperm, or hormones that preclude the release of eggs from the ovaries. The devices are safe and more than 99 percent effective, however, they can be difficult to insert. However, a new IUD inserter could make the contraceptive devices much more accessible, particularly for postpartum woman. The inserter was developed by Population Services International, in partnership with Stanford Program for International Reproductive Education and Services and Pregna International Ltd., costs just US$1, and is longer and sturdier than existing tools. In a trial enrolling 80 women in India each of whom had given birth just hours before, 90 percent of health workers reported that the IUD was easy to place with the new inserter and more than 90 percent of women felt no increase in pain during the procedure. Improved inserters could have a significant impact in settings without ultrasound technology—used to confirm the placement of the IUD—or with limited ability to sterilize equipment. Next Billion took an in-depth look at existing vaccines to prevent and treat cancer, emphasizing their need in low-resource settings, where cancer testing and treatment are often inaccessible and prohibitively expensive. Rather than targeting pathogens, these vaccines train the immune system to attack cancerous cells. There are currently preventative vaccines available against strains of human papillomavirus (HPV) and hepatitis B virus that cause cervical and liver cancer, respectively, and other vaccines available and under development can prevent the spread or relapse of bladder, prostrate, and lung cancer. Cervical cancer results in more deaths among women in low- and middle-income countries than any other type of cancer. Fortunately, HPV vaccines prevent against several strains of the virus, including the two responsible for 70 percent of cases. Liver cancer ranks second in cancer mortality worldwide, however, many cases could be averted with increased access to hepatitis B vaccines. Individuals infected with hepatitis B are 100 times more likely to develop liver cancer. Lung cancer is the leading cause of death from cancer worldwide, and non-small cell lung cancer (NSCLC) accounts for 85 percent of cases. However, researchers in Cuba are developing a therapeutic vaccine against NSCLC, which has extended survival rates for patients by 68 percent in phase 3 trials. Additionally, the TB vaccine is used to fight bladder cancer and the vaccine Sipuleucel-T is used against advanced prostate cancer.

US Senator Bernie Sanders (I-VT) released a plan last week as part of his Democratic presidential bid to incentivize research and development (R&D) for new HIV and AIDS medicines while ensuring they remain affordable. Under his proposal, drug companies would receive a cash prize for market introduction of a novel HIV and AIDS therapy, but would not receive exclusive marketing rights, an idea he first proposed in 2012. The prize would reflect the “therapeutic value” of the treatment as well as the number of people expected to benefit from the product. To finance these cash prizes, the Senator is proposing a Prize Fund for HIV and AIDS of US$3 billion per year. Eliminating exclusive market rights for these new drugs would ensure that generic products could immediately enter the market, spurring competition and lowering prices. However, critics argue that the proposal could take limited research funding away from other diseases and note that the plan does not detail how the size of the cash award would be determined for a given drug or to whom it would be distributed (i.e., the patent holder, the regulatory sponsor, public-sector agencies involved in the basic research, etc.). Photo: CDC The US Food and Drug Administration (FDA) announced last week its tentative approval of a trial of genetically engineered mosquitos to combat mosquito-borne diseases, pending 30 days of public comment. The mosquitos, developed by British company Oxitec, are intended to reduce the population of Aedes aegypti mosquitos, which transmit the Zika, dengue, chikungunya, and yellow fever viruses. The mosquitos are all male and when they reproduce with native mosquitos, their offspring are not viable, dying before reaching adulthood. The trial, if approved, will take place in the Florida Keys; Oxitec’s mosquitos would be released up to three times per week for up to 22 months. After a careful review, the FDA has determined, in collaboration with the US Centers for Disease Control and Prevention and the Environmental Protection Agency, that the trial is safe for humans, animals, and the environment. The agency noted that the trial will be short and that the Aedes aegypti “occupy a fairly uncontested ecological niche,” making it unlikely that another mosquito population would expand to fill the vacuum. The United Nations Children’s Fund (UNICEF) and the government of Malawi are conducting a pilot program to determine the cost, feasibility, and impact of using drones—unmanned aerial vehicles—to expedite HIV and AIDS testing for infants. In Malawi, 10 percent of adults are HIV-positive, and there are 130,000 children living with HIV and AIDS. However, it can take up to ten weeks to get HIV test results for infants born to mothers with HIV and AIDS, who require specialized testing. The blood samples are transported by ambulance or bike to one of only eight labs in the country capable of conducting these tests. It then takes at least two weeks for the tests to be completed, and often the results wait in the lab until there is a large batch. UNICEF and the Malawi government are testing the feasibility of drone delivery at different times and in different weather conditions and will be comparing the costs, which include electricity for charging the device and the hardware itself, to current delivery methods, which include fuel and driver salaries. The goal is to reduce testing time from more than two months to just a few days, ensuring that children with HIV and AIDS can start treatment much sooner.

A new study out of the Washington University School of Medicine in St. Louis, Missouri, revealed a proliferation of antibiotic-resistant bacteria in the gastrointestinal tracts of premature infants. The team collected fecal samples from 84 babies born premature and identified nearly 800 genes that enable bacteria to develop resistance to 16 different antibiotics. Preterm infants are more susceptible to infection and nearly all are given antibiotics preemptively for at least the first few days of life. However, this practice could have unintended consequences; high bacterial diversity in the gut protects against infection from harmful bacteria, and the study indicated that preterm infants have one-tenth the number of bacteria species found in babies born full term. The team used a novel technique to identify genes that can confer drug resistance, resulting in the discovery of hundreds of genes not previously associated with antibiotic resistance. Further, the findings suggest that administering one antibiotic can result in a growth in resistance to other antibiotics. However, breastfeeding and aging appeared to have a positive impact on the infants’ gut, resulting in increased bacterial diversity. A novel, low-cost technique can diagnose tuberculosis (TB) in 25 minutes using just a urine sample. Standard TB tests require X-rays and/or mucus samples, which are harder to acquire than urine samples, particularly in low-resource settings. In a study of more than 2,500 patients across four countries in sub-Saharan Africa, use of the test reduced TB deaths in HIV and AIDS patients by four percent, as improved detection enabled patients to start treatment early. In Africa alone, 300,000 HIV and AIDS patients die of TB annually, and thus, this diagnostic technique could save thousands of lives each year. The new tool costs US$2.66 per test, whereas the leading TB test costs $10 and requires a $17,000 machine to read the results. Last week, US government representatives met with scientists and public health officials to discuss a White House ban, instated 18 months ago, on research that makes viruses more dangerous than natural strains. Within the scientific community, many argue that such research can be done safely, and that the potential scientific and public health benefits are significant, whereas others contend that the benefits are overstated and the risk is too high. The officials met to discuss the establishment of a high-level committee which would review proposals for such studies, weighing the potential benefits and risks, evaluating the security of the laboratory facilities, and determining whether the results could be achieved through less risky research. Prior to the meeting, Dr. Inglesby—CEO of the UPMC Center for Health Security—along with Drs. Lipsitch and Relman of Harvard University and Stanford University, proposed policy options for conducting such research safely. The recommendations include: requiring a high-level official to approval such research (i.e., the director of the National Institutes of Health), defining “red lines” for research that would prompt additional safety reviews, limiting such research to select labs with the highest level of security, or requiring the purchase of insurance policies for such research.