Breakthroughs Blog: Polio

In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week. A new study suggests the Nanopatch vaccine delivery system is more efficacious in protecting against poliovirus than typical syringes or needles. Nanopatch, defined as “a microscopic vaccine delivery platform,” targets immune cells in the outer layers of the skin, as opposed to typical syringes and needles, requiring injection into the muscle. The change from muscle to immune cells results in easier administration of the vaccine as well as a reduction in the required dosage. While initial data on Nanopatch is promising, more research is needed. The World Health Organization has warned that an increase in antibiotic use in livestock will result in increased antibiotic resistance humans, potentially causing one of the biggest threats to human health. The agricultural sectors in both Europe and North America are advancing efforts to curb antibiotic use, but many countries are still lagging behind in efforts to scale back use of antibiotics. While new policies and reform around livestock antibiotic use are needed, experts note there is still a need to treat health complications in livestock, through antibiotic alternatives like animal vaccines, as well as a need for improved diagnostics. The World Health Organization, numerous aid agencies, and relevant stakeholders have announced the first global pledge to end cholera by 2030, following one of the worst outbreaks of cholera in modern history. Cholera is considered a “disease of the poor,” affecting individuals living in areas with poor sanitary and water conditions. The recent outbreak is associated with and exacerbated by weak health systems, poor infrastructure, and a lack of necessary supplies to prevent, diagnose, or treat cholera. The pledge will focus on a multifaceted approach involving improving water and sanitation as a long-term solution and use of an oral, three-year cholera vaccine to provide immediate protection.

In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week. Sanofi Pasteur’s announcement that it will cease work on its Zika vaccine candidate has raised concerns about the future of Zika vaccine development. While the World Health Organization has reported 40 Zika vaccine candidates in development, with six candidates in phase 1 clinical trials, Sanofi was the only major pharmaceutical company working on a vaccine against the virus. Its exit from this space raises questions about who will fund clinical development if these candidates show further promise. Additionally, many unanswered questions remain about the virus’s epidemiology and the target population for a vaccine. While the number of Zika cases is now falling, Zika epidemics will likely reoccur in the future. Because of this risk, developing an effective and low-cost Zika vaccine must remain a priority. Johnson & Johnson and the Biomedical Advanced Research and Development Authority (BARDA) have formed a partnership to develop vaccines and drugs to protect against pandemic influenza. Among its projects, the partnership is seeking to develop a “universal” flu vaccine that protects against all or most influenza strains. This collaborative effort highlights a larger trend in partnerships between the private sector, the US government, and nonprofits to develop vaccines and technologies against emerging health threats for which there is currently limited commercial market. Pakistan has launched its first nationwide vaccination drive for polio, aiming to immunize over 37 million children. Pakistan is one of just three countries where polio cases remain, so this nationwide drive is an important step toward eradication. While polio still remains endemic in Pakistan, the number of cases has reduced dramatically in recent years from 306 cases in 2014 to just 4 today. Pakistan has experienced obstacles in its attempts to eradicate the virus, which include efforts by extremists to target immunization campaigns.

In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week. While polio has continued on a path toward global eradication, there have still been many substantial obstacles. The most recent challenge has been the number of cases of polio reported due to the oral polio vaccine. The vaccine, containing a weakened form of the live virus, caused just over 20 cases of polio in 2017—more than the to-date cases of wild polio. Polio is considered a “smart” virus with the capability of mutating and regaining strength rapidly, causing more problems for areas of the world that rely on the live, oral polio vaccine. Even with the problems surrounding the live polio vaccine, the vaccine has saved hundreds of thousands of lives and is credited with driving down infection rates to near-zero. Once the majority of the population is vaccinated and cases of all polio infections level off, public health professionals can begin to taper off using the vaccine to ensure continued eradication. Pandemics are among the most likely uninsured risks to occur, risk modelers have argued. A moderately severe pandemic event could cost upward of US$750 billion and affect tens of countries across the globe. To combat this financial risk, the World Health Organization (WHO) launched a pandemic bond program to prevent this risk. The bond program—called the Pandemic Emergency Financing Facility (PEFT)—would provide substantial funds to any country affected by a pandemic, and the turnover of the funds would be quick. If a program like PEFT existed during the 2014 Ebola pandemic, millions of dollars and thousandsof lives could have been saved. Instead, countries like Liberia and Sierra Leone struggled to come up with the funds to cover the various expenses associated with pandemics. Investors are already keen on buying into the bond program, suggesting it will be successful in the long-term effort to curb the disastrous effects of a moderately severe pandemic.  A generic version of a popular HIV antiretroviral drug recently launched in Kenya, making it the first country to debut an affordable HIV treatment. The drug launch is a part of a larger Optimal ARV Project, with the goal to increase access to treatment in areas of the world affected by HIV and AIDS, malaria, and tuberculosis. The antiretroviral is one that is most commonly used around the world, including the United States, with quick, positive results and minimal side-effects. While the daily regimen of taking antiretroviral drugs is still a tedious and essential set of tasks, the generic version offers poor individuals in remote-access areas the ability to use the drug with increased frequency, achieving better results, and driving down incidences of HIV.  

Researchers at the University of Cape Town discovered a compound that blocks the cycle of malaria within the human body, regardless of its drug-resistant status. The compound acts a preventative tool as well as a treatment for those infected with malaria, as it can block transmission and prevent infection. The compound, MMV390048, began phase I clinical trials in 2014, but subsequent data has not yet been published. The drug will enter phase II clinical trials this year in Ethiopia, and it is hoped this drug will be on the market within the next ten. With the world circling in on polio eradication, global public health professionals have run into a major obstacle that makes ridding the disease incredibly complicated: A vaccine shortage. There currently isn’t enough injectable polio vaccine for the world to use, as demand is so high. There isn’t enough of the vaccine in production for each child to receive two shots, which is what researchers suggest to protect against contracting polio. An alternative is the oral polio vaccine, but due to its heightened risk of complications, professionals believe this vaccine will soon be phased out. While polio vaccine manufacturing may be ramped up to treat children in the next few years, it is essential that health care professionals continue to vaccinate children ten years post-eradication to ensure there is no resurgence of the disease. Funders, including the Gates Foundation, are now putting efforts toward the next surge in vaccine demand, and hope to overcome this obstacle to reach global eradication of polio once and for all. An outbreak of Ebola has been confirmed in the Democratic Republic of the Congo (DRC), and health researchers around the globe are working to distribute an experimental vaccine. While the outbreak is contained due to the geographic isolation of the cases, the WHO and Gavi are still working quickly toward an effective and globally approved vaccine that can be used in future outbreaks. The DRC has not requested a vaccine at this point in time, but these organizations are prepping for when the country requests it, or for if the outbreak spreads past the DRC. The vaccine is experimental, and requires special modes of transportation, yet proved incredibly successful during the Ebola outbreak of 2014.