 Olivia Twenty Dahl (1955-1962) In 1962, a seven-year-old girl named Olivia brought home a note from school warning about an outbreak of measles in her class. Soon Olivia too was running a mild fever and covered with red spots. Over the next few days the disease ran its expected course, and her parents weren’t particularly worried. To while away the time, her doting father amused her by telling her stories, teaching her to play chess (at which she promptly beat him), and showing her how to make figures from pipe-cleaners. Then one morning, just as Olivia appeared to be nearly recovered, her father noticed that she had suddenly become feverish and unresponsive, stirring only to moan about a headache. Within just a few hours she was dead from measles encephalitis, a serious complication for which to this day the best medicine can offer is supportive care. Olivia’s father, Roald Dahl, author of such children’s classics as Charlie and the Chocolate Factory and James and the Giant Peach, was “limp with despair.” Dahl was a “do-something” sort of person. When his infant son had suffered brain damage in an accident a couple of years earlier, he had actually set about to design a valve to prevent blockage of the shunt that drained fluid from the brain - and succeeded. He was no biomedical engineer, but when the need arose, he assembled a small team and acquired sufficient expertise to meet the challenge. Now, with Olivia’s life hanging in the balance, there was nothing he could do. He was haunted by his sense of helplessness, compounded after her death by inchoate feelings of guilt that he had somehow let his daughter down. And yet, what could he have done? Twenty-six years later, hoping to extract some shred of meaning from Olivia’s death by sparing others a similar fate, he wrote, “[T]here is today something that parents can do to make sure that this sort of tragedy does not happen to a child of theirs. They can insist that their child is immunised against measles. I was unable to do that for Olivia in 1962 because in those days a reliable measles vaccine had not been discovered. Today a good and safe vaccine is available to every family and all you have to do is to ask your doctor to administer it.” * * * * * * * * * * Measles. The very word sounds slightly risible. Like “Measles the Clown,” perhaps. Or trifling. Like “just some measly childhood disease.”  (courtesy of the Centers for Disease Control and Prevention) But measles is no joke. It is highly contagious and can be spread by an infected person up to four days before before the telltale rash emerges, via tiny airborne droplets produced by sneezing or coughing that remain suspended in the air for two or more hours, even if the infected person is no longer in the room. In many victims the disease runs a benign course, but one in ten are hospitalized, some of whom suffer serious complications including pneumonia and encephalitis. Around 1 or 2 in every 1,000 victims die. Prior to the development of a vaccine, nearly everyone in the US contracted the measles by age 15 - that is, an estimated 3 to 4 million cases/year - so the mortality rate of .1-.2% added up to many thousands of victims per year, mostly children. Measles still causes more vaccine-preventable deaths worldwide than any other infectious disease. A live measles vaccine was first licensed in 1963, just a year after the tragic death of Olivia Dahl, and was superseded by an improved version in 1968. In the twenty years following its introduction in the US, an estimated 52 million cases of measles were prevented, with corresponding dramatic reductions in measles-related complications and death. In the year 2000, measles as an endemic disease was officially “eliminated” from the US; the only reported occurrences of measles were occasional cases introduced from abroad. Truly a public health triumph. Though measles persists globally, most notably in developing countries, aggressive vaccination campaigns have resulted in a precipitous drop in mortality from measles complications worldwide, with a 75% decrease between 2000 and 2013. We now have a measles vaccine that is 97% effective after a single dose and close to 100% effective after a booster dose, which has been recommended since 1985. (Note: People born between 1957 and 1984 should review their immunization status with their doctor, especially if they are planning foreign travel.) To reduce the pain of multiple injections, the vaccine is almost always administered in combination with vaccines for mumps and rubella (MMR) - the first at 12-15 months (earlier if travel abroad is planned), the second at 4-6 years. The rate of serious or life-threatening complications following MMR vaccination is vanishingly small. Although there is NO evidence whatsoever to support a link between MMR vaccine and autism, and although that claim has long since been proved a hoax, the preservative thimerosal (the supposed villain) is no longer used in any vaccine administered to children. As a result, “do-something” parents like Roald Dahl actually have something they can do to ensure that Olivia's fate is not shared by their own child: "They can insist that their child is immunised against measles.” * * * * * * * * * * End of story? Sadly, no. For a disease that’s supposedly been eliminated, measles seems to crop up in the news surprisingly often. After reaching a low of 37 cases in 2004, we now spike record highs every few years, peaking at 667 cases in 2014. A 2013 outbreak occurred at a megachurch in Texas whose pastor had preached from the pulpit against vaccination. In 2015, nearly 200 cases in 24 states were traced to exposure after visits to Disneyland in California. Currently making headlines is an outbreak in Minneapolis, starting in the Somali-American community (fueled by anti-vaccine advocates from outside the community who prey on worries about autism, a malicious genie that refuses to go back in the bottle) and fanning out into the surrounding population through contact in the public schools.
These outbreaks are all shots over the bow. Because international travel is so commonplace, the occasional introduction of measles from abroad is inevitable so long as the disease remains a global scourge. Even more troubling is the occasional case in which no known link to international travel can be found, raising the specter that the disease might once again become endemic. But regardless of the source of any given case of measles, what happens next - whether that single case is self-contained, leads to isolated regional outbreaks, or triggers a full-blown epidemic - depends on how many susceptible individuals are subsequently exposed. Who are these susceptible individuals? As noted above, a handful remain vulnerable even though they have been vaccinated - especially if they have not received a booster dose. In addition, some people are ineligible to be vaccinated because they are very young or very old, because their immune systems are compromised due to illness, because they are pregnant, or in very rare instances because they are allergic to some component of the vaccine. The rest of the susceptible population consists of individuals - mostly children - who though medically eligible have not been vaccinated - and herein lies the problem. Because measles is so highly contagious, vaccination coverage needs to be reach around 95% to maintain “herd immunity” and prevent further spread once a case is introduced. Doing the math, almost everyone who is medically eligible must be vaccinated to prevent the spread of measles, on a regional level or potentially on a much larger scale. Epidemiological studies of measles victims have repeatedly shown that most had not been vaccinated, and of these, the majority had been exempted for non-medical reasons relating religious or philosophical beliefs, or to the systematic spread of discredited data about the health risks of vaccinating (negligible) vs not vaccinating (potentially lethal). Consequently, vaccination rates continue to fall short of the 95% threshold in communities in many areas of the country. The underlying cause of the societal breakdown that could lead to such a situation is difficult to pinpoint. Parents may be uninformed about the importance of completing immunization schedules in a timely manner or persuaded that they cannot trust scientific findings or governmental protections. They may believe their responsibility to their own children takes precedence over the social contract stipulating that we all accept small risks to avoid much larger risks to society as a whole, without understanding the risks to which they subject their own children by leaving them defenseless against measles. Government agencies in turn may succumb to pressure to issue non-medical "personal belief" exemptions or be reluctant to enforce existing vaccination requirements. People with far more expertise than I can claim have yet to figure out where to intervene in this chain and how hearts and minds can be changed. Part of the problem, of course, is that thanks to the very success of immunization campaigns, many Americans have lived their entire lives without having witnessed the ravages of a major epidemic. Let us hope an answer can be found that doesn't require a reintroduction of some of the terrifying communicable diseases medical science has conquered. How fortunate we are to live in a time and place where children like Olivia no longer need to die as their parents stand by helplessly. How sad that some will anyway, and that there is no immediate end in sight to this trend.
0 Comments
Smallpox vaccination, the first successful vaccine in Western medicine’s toolkit, was developed by Dr. Edward Jenner in 1796 after he observed that milkmaids who had caught cowpox, or Variolae vaccinae, a much milder disease, never developed smallpox. Indeed, the term “vaccine” comes from the Latin word for cow. The term vaccine originally referred specifically to smallpox vaccination with the cowpox virus; in 1881 Louis Pasteur, to honor Jenner’s achievement, proposed applying the term generically to all protective inoculations. But before there was Edward Jenner, there was Lady Mary Wortley Montagu. Lady Mary, whose husband served as British ambassador to Constantinople, had occasion while living in Turkey to observe a practice called “variolation.” “Variolation” in some form - involving exposure to a weakened form of smallpox - had long been practiced in parts of China, India, Africa, and the Ottoman Empire, and it was clear to Lady Mary that the procedure was both safe and effective. Having lost a brother to smallpox, which claimed the lives of around 35% of its victims, and having herself been left severely and permanently scarred by the disease, she was prepared to use any means at her disposal to spare her children a similar fate. In 1718 she had her 5-year-old son variolated in Turkey; in 1721, after her return to England, she had her daughter variolated as well during a smallpox outbreak, thus introducing the practice to England.  I studied Lady Mary’s writings back in the 1970s, in the course of my research on autobiographies of 17th and 18th century English women. Lady Mary wasn’t a physician or a scientist, nor did she see herself as a medical pioneer. She was simply a devoted mother who used her keen powers of observation and the resources at her disposal to protect her children as best she could. She did exactly what most mothers, guided by the best information available to them, would do in her situation. As a noblewoman, she was also aware that her actions could influence British “fashion” and assumed her example would inspire other mothers to do the same in order to protect their own children - as indeed to some extent it did. (She was far less confident that the medical profession would adopt a practice that would reduce their revenue!) Smallpox vaccination is one of the great successes of modern medicine. In fact, the last endemic case in the world occurred in Somalia in 1977, and no one in the US has been vaccinated since the early 1970s. This is one of the few instances in which not vaccinating is truly safer than vaccinating, since even the rarest or mildest of adverse reactions is unacceptable when the likelihood of anyone’s coming down with smallpox is essentially zero. So far smallpox is the only infectious disease ever to be eradicated. Other candidates such as measles and polio still elude eradication; unfortunately efforts to do so are hampered by campaigns inspired by politics, religion, or anti-science to undermine confidence in vaccination.  Selfie of my smallpox vaccination scar, almost faded but still visible on my upper arm. You will seldom see this telltale mark on people in their mid forties and under. Once my generation passes they will probably never be seen again. |
Categories
All
Archives
February 2018
|
RSS Feed
