Protect Against the Pox

When I was an intern a child who had diphtheria came to the emergency room. During the next 24 hours all the younger members of the medical staff visited the child because none of us had ever seen anyone with this illness. Today, many experienced physicians and even pediatricians have never seen a child with this disease.

In the 1930s, 7,000 children died of whooping cough each year in the U.S. Now, whole years go by without a single fatality due to this once terrible disease. These diseases have been almost eradicated by immunization programs.

The discovery of this medical miracle is worth retelling as it shows that you do not necessarily have to have a million-dollar research grant to come up with wonderful discoveries. Edward Jenner was a country physician in England two centuries ago. He noticed that when epidemics of smallpox occurred, certain people in his village did not catch the disease. After some thought, he realized that it was the people who were in close contact with cows who seemed to be immune. He also noted that they had all been infected with cowpox, a minor disease with some similarities to smallpox. The next step was to try to deliberately cause patients who had not had cowpox to become infected. He took scrapings from a sore of a patient with cowpox and placed it over a scratch on the skin of the patient that he wished to treat. The patients caught cowpox and were then found to have protection when the next epidemic of smallpox arrived in the village. The Latin word for cow is vacca; cowpox is vaccinata: hence the word 'vaccination.' I have read recently that this method may have been discovered independently in China.

Immunization programs throughout the world have been the most successful public health initiatives ever. Some parents, for quite understandable reasons, have started to question the need for these shots and have decided to not have their children immunized. This is partly due to the fact that almost nobody remembers these diseases as they have hardly been seen for more than half a century. It is the very success of these programs that has led parents to question their necessity. Fortunately, most countries have regulations that insist children have coverage before they are admitted to school.

Once children have been given these vaccines they have almost complete protection from these nasty infections. It is less well-known that at the age of ten or eleven the pre-adolescent child needs to be reassessed and revaccinated. American government health services advise that adolescents who have not been vaccinated against varicella (chicken pox) and hepatitis B have these vaccines at this time and also have a booster shot against measles, mumps, rubella (MMR) and diphtheria tetanus (DT). 

The newest recommended vaccine protects against chicken pox. It has only been available since 1995 and there has been little publicity about its availability. The varicella virus causes epidemics of chicken pox, usually in the winter and spring. After contacting the virus there is a long incubation period, usually about 14 days, although it can be as short as 10 days or as long as 20 days. A mild fever and a general feeling of discomfort are the first signs of the illness. The rash is composed of many small spots; they often start with the appearance of a little blister which then breaks down to leave a painful weeping area. They usually first appear on the head and trunk. 

Anyone who has had a child with this disease will remember the attack. In addition to the general feeling of malaise that goes with the fever, the spots can be extremely tender.

Recovery is usually fairly quick and the spots normally heal with no damage. The risk of serious complications is small, but cannot be ignored. One child in 100,000 can die from neurological and other complications and this rate is much higher in adults. The virus may stay in the body and can reactivate years later as 'shingles,' a disease where little blisters appear in bands around the body,  causing a great deal of pain. 

As an obstetrician I am very concerned about the effects of this disease and feel that we should do as much as we can to reduce outbreaks. If a woman in the first four months of pregnancy should come into contact with a patient with chicken pox and she does not have protection then the baby may be damaged, although this risk is not nearly as high as the risk that occurs with exposure to rubella. Unfortunately it is not always easy to know whether the mother has been infected. Blood tests are not widely available in Beijing and in any case are not as reliable as for other illnesses. 

The risk to the baby is very small -- one to two percent -- but this makes the decision of what to do very difficult. Another difficult situation is if the baby is born within five days of the mother becoming infected. The baby may be born with the disease and this can prove fatal to the baby in as many as 30 percent of cases.
Last winter in Beijing there was an outbreak of chicken pox and there were several pregnant patients, many of them schoolteachers, who were very distressed, as they had had contact with infected children. Waiting to see whether the rash would develop was an incredibly nerve racking experience for these expectant mothers.

I would urge anybody who has not had the disease in the past or has not had the vaccine to consider being vaccinated. Many people may not remember whether they have had an attack or not. Talk to your parents and ask them if they remember if you had an attack as a child. As the vaccine has only been available for five years, many children who are over the age of four may not be protected. There are a few people that are not suitable candidates for this treatment. Patients taking steroids, pregnant women or women who intend to get pregnant within one month should not take the vaccine. One strategy is to give the vaccine to any woman who is planning to be pregnant in the next year or so if she has not had an attack in the past. It is unfortunately quite expensive -- US$130 for the two shots.

By immunizing yourself and your children, you not only protect your family but also reduce the risk of an epidemic by decreasing the available pool of people that can get the disease. 

-- Dr. Moreton is an obstetrician and gynecologist at Beijing United Family Hospital.