By: Allison Dennis, BS
Keeping up With the Synthetic Opioids
At the center of the opioid crisis is an ever-expanding class of would-be-regulated drugs, exploited for their ability to produce morphine-like effects. Opioids, including morphine, heroin, and oxycodone interact with the opioid receptors found on the surface of our nerve cells to trigger feelings of euphoria, and block pain. Unfortunately, these substances can adversely affect the respiratory rhythm generating area of the central nervous system, resulting in respiratory depression, effectively disrupting the body’s instincts to breathe.
In 2013, the U.S. Drug Enforcement Agency began to detect in confiscated supplies of heroin the synthetic compound, Fentanyl, which is 50 to 100 times more potent and carries a much higher risk of respiratory depression. The supply was traced to illicit online pharmacies in China, prompting Chinese officials to implement an export ban on fentanyl. Just as medical drug makers audition new compounds through structure-based drug design, illicit drug makers quickly modified the structure of fentanyl to produce furanyl fentanyl, temporarily circumventing the ban. This was followed by the production of the elephant tranquilizer, carfentanil. As of March 1, 2017, China has placed a ban on the sale and manufacture of these compounds along with acrylfentanyl and valeryl fentanyl.
However the dynamic that has emerged is a global game of whack-a-mole. Cutting off the global supply of fentanyl-derived compounds will require negotiations with individual governments to cooperate in their ban. Willing chemists in Mexico may already be setting up to fill the gap left by the ban in China. As each substance is entering the U.S. Drug Enforcement Agency’s radar, the list of designer fentanyls is expanding. The rotating portfolio of synthetic opioids has left local law-enforcement and coroners stumped as to how to test for drugs not-yet-known to their screens, leaving a critical lag in identifying local suppliers. (Eric Niler, Wired Magazine)
Keeping up with the Neuraminidases
The H7N9 strain of bird flu may be gaining ground as a global threat to human health. On Monday, the U.S. Department of Agriculture confirmed the presence of a highly pathogenic H7 avian influenza strain in a flock of chickens in Lincoln County, Tennessee. The agency is hurrying to establish the neuraminidase protein type, or “n-type” of the virus. In combination with the H7 hemagglutinin type, an N9 would consign this virus to the class of influenza the WHO has described as “definitely one of the most lethal influenza viruses we have seen so far.”
First detected in China in 2013, the H7N9 strain has been the source of yearly epidemics of human infections. These infections are characterized by severe respiratory illness, which has lead to death in 40% of cases. Over 5 flu seasons, 1222 human cases of H7N9 flu have been confirmed. Most infections have been tied to direct exposure to poultry where the avian strain circulates, indicating that the virus is not currently suited for sustained person-to-person spread. However, the ability of these viruses to recombine, gaining new specificities, keeps public health officials watchful.
Following the first reports of H7N9 infections in humans in 2013, the U.S. Department of Health and Human Services amassed a 12 million-dose stockpile of H7N9 specific vaccines. However, the strains selected as the seeds for these vaccines may not adequately protect against the particular H7N9 virus circulating now. The U.S. CDC is currently evaluating the need to update its vaccine stockpiles in addition to recommending inclusion of H7N9 in next year’s seasonal flu vaccine. Many researchers are hoping to circumvent these concerns with the development of a universal vaccine, protective against all known flu strains. (Helen Branswell, STATnews)
Have an interesting science policy link? Share it in the comments!