The tragic and cowardly attacks on the United States on September 11, 2001 have forever changed the way in which Americans will live their lives. We have become more vigilant and aware. The Homeland Security Team put together by the Bush administration has taken a pro-active and readied approach to the threat of terrorism. In the era of instant news and “team coverage,” Americans are made aware daily of the risks they face. Dirty bombs, anthrax, botulism and smallpox are terms that we hear every single day.
Prior to 9/11, a good portion of a pediatrician’s time was spent educating parents about the benefits of immunizing their children against the preventable childhood illnesses...and how ill-advised it would be to NOT do so. Every now and then, a worried parent would come in with information they had read on the Internet or heard on the news somewhere, about how certain immunizations could cause autism or some dreaded illness. Since 9/11, however, more and more concerned parents are ASKING about the smallpox vaccine...when and where they can have their children and themselves immunized. This is the stark reality of the day.
The Red Book is a publication put out by the Committee on Infectious Diseases for the American Academy of Pediatrics. It is revised and updated every three-to-four years. When searching for smallpox in the index of the 1994 edition, one reference to page 7 states, “The global eradication of smallpox was achieved in 1980 by combining an effective immunization program with intense surveillance and adequate public health control measures worldwide”. The 2000 edition of The Red Book gives two references to smallpox; one of which is a table that outlines “Biological Weapons-Treatment Precautions-and Isolation”. It will be interesting to see how much is written about smallpox in the upcoming edition.
Leafing through a chapter on viruses in a standard, current medical or pediatric textbook, it is noticeable that much has been written about new challenges facing the medical community. Hanta virus, Ebola virus, new strains of hepatitis and the retroviruses that cause HIV fill the section about viral illnesses. There will be NO mention of smallpox (Variola). That is because the World Health Organization declared smallpox eradicated throughout the world in May of 1980. The last endemic occurred in Somalia in October of 1977. During the 1980’s there were only two known samples of smallpox that existed in the world. One was at the Center for Disease Control (CDC) in the United States, and the other was in the former Soviet Union. There was talk about simultaneously destroying the remaining strains, but this never occurred. With the breakup of the Soviet Union, intelligence experts have feared that the security of the Russian supply of smallpox might have been compromised and actually sold on the “black market”. This has probably become a reality as terrorist groups are well funded, and access is not a problem.
Sadly, a devastating disease such as smallpox that was once wiped off the face of the earth is now a potential weapon to be used in the most cowardly manner against one’s fellow man. Smallpox, or Variola, is an acute viral disease that first enters the respiratory tract after which it spreads throughout the body via the bloodstream. The incubation period is 12 - 21 days after which time a prodrome occurs. This includes headache, chills, muscle aches and a high fever--up to 106 degrees. During the first couple of days there may be a transient, non-specific rash on the upper thighs and buttocks, but this disappears after a day or two. By the fourth-to-fifth day the classic vesicle, or blister-like rash, appears on the face, forearms and upper arms, chest and abdomen. These lesions are raised and red at first. Then they become fluid filled with a clear fluid that progresses to a green or grayish-yellow color. These vesicles, which may be deep, also involve the eyes, mouth and throat. After about 10 days, the lesions begin to dry out; at 14 days they begin to crust. By the third week, the scab will fall off leaving permanent scars in over 50% of the survivors. Complications of smallpox include pneumonia, secondary skin infections, viral infection of the bone and cartilage and potentially lethal swelling of the throat and airway. Smallpox is a devastating illness that carries with it a mortality rate of up to 30%.
This summer, the CDC and the Advisory Committee on Immunization Practices met to discuss the threat of smallpox and to set up a pro-active plan for handling a terrorist attack. They recommended against immunizing all Americans at this point in time. Instead, they have designated smallpox response teams, Type C centers, which will respond to any suspected cases of smallpox. The physicians and health care individuals of these Type C centers will be immunized along with epidemiologists, lab scientists, nurses and law enforcement. The estimated number of Type C team members would be around 15,000 to 20,000.
Should a case of smallpox be identified in the United States, the strategy would be to initiate a “ring vaccination” plan, whereby all household members and close contacts would be immunized. It has been well established that post-exposure vaccination, giving the vaccine after one has been exposed to smallpox, will greatly modify or even prevent the disease. Unlike measles, whereby one can transmit the disease BEFORE being clinically ill, in order for one to spread the smallpox virus, they most certainly will be gravely ill. The likelihood of such an individual boarding a plane or a train, or milling about public areas without being noticed is rare.
The history of smallpox vaccine is an interesting one. In 1798, Jenner proved that inoculating humans with material from “cowpox” could prevent them from getting smallpox. Cowpox (vaccinia) and smallpox are so closely related that when one is given cowpox, one is also protected against smallpox. In reality, the smallpox vaccine that was used to eradicate the disease worldwide was actually derived from the underside of calves that had been infected with cowpox. Since this vaccine is not manufactured in a sterile environment it is not without complications. The vaccine made from vaccinia is a live virus. It basically “infects” one with a less serious disease with the resultant protection against smallpox. Since it is a live virus, the recipient of the vaccine may shed the virus to others for a period of two weeks. Individuals whose immune system is compromised are at risk when exposed to vaccine recipients during this time period. Therefore, doctors who receive the vaccine would need to be careful not to come in contact with these “at risk” patients for a period of up to two weeks, during which time they could shed the virus. Giving the vaccine itself to an immuno-compromised person is contra-indicated, for the results could be devastating. These immuno-compromised individuals would include patients with HIV, organ transplantees, pregnant women and people on high dose steroids. There are a large number of individuals walking around who are not aware that they are HIV positive. The question of universal immunization against smallpox is not an easy one. It is estimated that the mortality rate from the smallpox vaccine (actually vaccinia) during the 1960’s was about 5 per million. The incidence of post-vaccine encephalitis was approximately 2 - 6 per million.
Two vaccines against smallpox that are currently available are both derived from vaccinia virus of infected calves. These vaccines will never be licensed because of concerns about contamination. There are two new “cell-culture” vaccines that are in phase II of testing, which means that they will probably not be licensed before late 2003 or 2004. Although these vaccines are much safer and purer, the protection that they will offer against smallpox remains to be seen. None of the studies currently being done involve children. If they are licensed and used in the event of a bioterrorist attack of smallpox, they might be used in children without ANY testing. This poses a real dilemma to the Health Care community and there are no simple answers.
It seems surreal to be writing such an article in the year 2002. To think that mankind could have reached this point is mind-boggling. Yet, this is the reality! We, as Americans, must put our trust and faith in those we have selected to lead us. We must be informed and vigilant. We must keep level heads and not give in to the hysteria and hype that surrounds us daily. Knowledge is vital. The only way to be prepared is to read and ask questions so that we may be better prepared to sift through the plethora of information that bombards us.