Why does the body sometimes fight against infection, and sometimes against itself? Akiko Iwasaki, PhD, Waldemar Von Zedtwitz Professor of Immunobiology and Molecular, Cellular and Developmental Biology, and a Howard Hughes Medical Institute investigator, has spent over two decades studying the question, and is one of the foremost experts in her field. As such, she has been vocal about the dangers of COVID-19, a viral infection that sometimes provokes a type of autoimmune response that overwhelms the body and can lead to fatality.“In certain patients, the immune system actually goes into overdrive,” said Iwasaki. “Instead of simply getting rid of the virus, the immune system secretes cytokines... instead of helping the host cope with infection, the cytokines actually can cause damage to the tissue.” With COVID-19, in those cases where the patient’s immune system malfunctions, a “cytokine storm” attacks the tissue lining of a person’s lungs and blood vessels, flooding many alveoli (tiny air sacs in the lungs) and preventing oxygen exchange. “That’s why people have shortness of breath, because they no longer have enough oxygen in the blood coming in through the alveoli, because the alveoli are full of fluids,” said Iwasaki.Iwasaki has been a prominent voice explaining to the public what is happening to patients suffering from the cytokine storm, many of whom are elderly, immune-compromised, or have underlying immunological conditions. Echoing the guidance of epidemiologists like Saad Omer, PhD, of Yale Institute for Global Health, and Gregg Gonsalves, PhD, of Yale School of Public Health, both of whom have also explained the danger to populations and individuals, Iwasaki has stressed the importance of social distancing, and avoiding crowded places. My laboratory is currently working very hard to try to understand the immune responses that occur in COVID-19 patients.Akiko IwasakiThere is another component of COVID-19 that worries Iwasaki as an immunologist; because it is a new type of infection, few people have any preexisting immunity to COVID-19. This state of immunological vulnerability—known as being “naïve”—means the virus has a greater and more dangerous effect on even a healthy individual.It also means there aren’t vaccines or effective treatments—something Iwasaki is working to change. “My laboratory is currently working very hard to try to understand the immune responses that occur in COVID-19 patients… right now we don’t understand what kind of immune responses are needed to recover from the infection, versus what types are driving the disease,” she said. “If we can figure this out, we can have better therapy and better vaccine strategies.”In the meantime, said Iwasaki, people “need to keep social distancing measures. Also washing hands, and really keeping a healthy lifestyle so that your immune system is as optimal as it can be, which includes eating healthily and exercising and getting enough sleep.” While Iwasaki and scientists hard at work in her laboratory seek insights by which to accelerate the search for effective vaccines and treatments, she remains convinced that the best thing people can do to combat COVID-19 is to stay home.