What You Can't Catch Might Kill You
NCDs are in the news. Last week, the United Nations held a two-day summit on non-communicable diseases—NCDs—and we now have a new term to digest.
For years, public health folks have focused on communicable disease, that is, diseases you can catch from someone or something. For measles, mumps, whooping cough, tetanus, they advise you to get your childhood immunizations. For food-borne illness, like salmonella or botulism, they inspect restaurants and food processing facilities. As for waterborne disease (think traveller’s diarrhea), they have been so successful at eradication that we can take the quality of our water for granted.
NCDs are diseases you don’t catch. For the most part, they result from choices that individuals make every day that increase their risk of heart disease, lung disease, diabetes, and cancer, among others. These NCDs generally develop slowly and quietly with increasing cost to individuals in reduced quality of life and to society in increased demands on the medical care system.
Communicable diseases used to be the major cause of mortality—think TB and the plague. In 1854, there was an outbreak of cholera in a poor area of London. At the time, it was generally thought that cholera came from breathing “bad air.” Dr. John Snow, however, saw patterns in where the cases were occurring that suggested the source was water from the Broad Street pump. This was before water was piped to houses, and the pump had become contaminated, putting all who used it at risk. The city removed the pump’s handle to cut off the source of infection.
Today, NCDs have become the most important threat to health and life in the U.S. and other high-income countries and, as the UN conference highlighted, increasingly in lower-income countries as well. Where is the “contaminated pump” for NCDs?
The causes of NCDs are known. Tobacco use is the biggest contributor in the U.S., where an estimated 18% of all deaths are due at least in part to tobacco. But obesity is a close second (some 12-15%) and rising fast. Obesity is generally a result of “energy imbalance,” which means you take in more calories than you expend in physical activity.
Clearly, the problem is broader than one infected pump. In many urban neighborhoods, cigarettes are more easily bought than jump ropes, and chicken nuggets are easier to find than fresh fruit. Streets are designed for cars with little accommodation for bikes, and sidewalks aren’t always safe enough for children to walk to school or the playground, if there is one. Residents who want to eat well or get daily exercise have a harder time than those whose urges are less healthy.
Addressing the causes of NCDs is going to be a lot harder than disinfecting a pump. The “pumps” are much more numerous; temptation is on every corner. Moreover, instead of fixing something people recognize as dangerous, the task is to try to discourage them from something they find pleasurable and, in the case of fast food, that isn’t dangerous in moderation. The challenge then, as the public health folks often say, is to make the healthy choice the easy choice.
There is another challenge as well, one that Dr. Snow also faced. In 1854, several years before the germ theory of disease was accepted, admitting that contaminated water was linked to the cholera outbreak meant telling people about the oral-fecal route of disease transmission, not a pleasant thought, and London’s officials declined the opportunity. Today, reducing NCDs means recommending that people give up things they like and nudging them and the businesses that promote unhealthy behaviors toward more responsible consumption. Could it be that one day we will look back at our unbridled eating and smoking with the same disbelief with which we regard contamination of a public water supply?