It's impossible to make vaccines to bioweapons

There is no universal flu vaccine. There are no vaccines with long-lasting protection against malaria or tuberculosis. None for parasites like Chagas, elephantiasis, hookworm or liver flukes. None for some viral threats that could become pandemic, like Nipah, Lassa and Middle East Respiratory Syndrome. None for some that already have, including Lyme, West Nile, Zika and hepatitis C. None for respiratory syncytial virus, which kills infants, nor even for the dozens of causes of common colds. Vaccines are among the world’s greatest medical advances, like clean water, soap, bleach, sewage systems and antibiotics. In a rational world — one where budgets are built on lives saved per dollar — spending on vaccine research would rival that on defense research. And progress would be as rapid. When Louis Pasteur was born, soldiers carried muskets. Now, a Taliban fighter can be killed by a drone flown from a base in Arizona, but vulnerable Americans still have to rely on a flu-shot technology invented in 1931: growing vaccine in chicken eggs. And as with weaponry, fear changes everything. In epidemiologically quiet times, the anti-vaccine lobby sows doubts; when Ebola or pandemic flu strikes, Americans clamor for protection. There are two obstacles to faster progress, said Dr. Gregory A. Poland, director of the vaccine research group at the Mayo Clinic. “One is scientific, and one is embarrassing,” he said. The embarrassing part is the lack of investment. It takes 10 years and more than $1 billion to develop a vaccine — a small fortune for a medical advance but a pittance for a weapons system. While defense research is driven by one mega-customer, the Pentagon, vaccine researchers face a confusing hodgepodge of potential backers. Private industry largely pursues high-priced vaccines for American children, militaries and adventure tourists. Potential bioweapons like anthrax, plague and rabbit fever attract bioterrorism funds. But vaccines meant to protect only poor people in faraway countries usually must wait for donor governments and philanthropies like the Bill and Melinda Gates Foundation and the Wellcome Trust, even though we know these plagues cross borders. The scientific obstacles, though more intractable, are relatively rare. Many pathogens are genetically farther apart than rhinoceroses and bees: A defense against a horn does not protect against a sting, and vice versa. Most vaccines work by creating antibodies — Y-shaped proteins — that block the disease agent’s own proteins. While viruses have only handful of target proteins, bacteria have up to 6,000 and parasites even more, noted Dr. Paul A. Offit, director of vaccine education at the Children’s Hospital of Philadelphia. And even some smallish viruses, including H.I.V., flu and hepatitis C, mutate so rapidly that their surfaces change shape before antibodies can lock onto them. As a rule, if a disease normally leaves even a few survivors who are completely disease-free and immune for life, a vaccine against that disease is possible. “Natural infection is the mother of all vaccines,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases. Smallpox meets the criteria; H.I.V., malaria and tuberculosis do not. H.I.V. mutates as fast in one day as flu does in a year; it also survives by splicing its DNA into the very immune cells that hunt it. TB bacteria can survive even when “walled in” by white blood cells. And malaria, a shape-shifting parasite, never triggers lifetime immunity. People who survive repeated bouts get less sick each time, but that immunity disappears if they move out of the malarial region. If they return, the first mosquito bite may kill them. Other diseases are complex, with many subtypes. For example, Pneumovax 23, the anti-pneumonia shot given to middle-aged people, negates 23 strains of one bacterium.