Public Health Feature -- May 2002
By Ken Ortolon
With Texas ranked dead last in the nation in making sure young children get their recommended immunizations, it would seem the news couldn't get much worse.
But it has.
Pediatricians and state public health officials say ongoing shortages of vaccines against serious childhood diseases such as measles, diphtheria, and chicken pox are hurting efforts to improve childhood immunization rates in Texas. And, if the shortages persist, Texas could see serious outbreaks of some of these diseases.
"In the last two years we've really been faced with remarkable problems," said Plano pediatrician Molly Ann W. Droge, MD, president of the Texas Pediatric Society. "We're just a time bomb sitting here waiting for outbreaks of vaccine-preventable diseases."
The Shrinking Supply
Dr. Droge, who also serves on Texas Medical Association's Committee on Child and Adolescent Health, says both Texas and the nation have experienced severe shortages in vaccines to prevent eight of 11 illnesses addressed in the regular children's immunization series.
"We're having to postpone these vaccinations," she said. "We're having to ration the vaccines. This is a great concern. These diseases are still present. If children don't get the immunizations as they're prescribed, these diseases will start showing up again."
Officials in the Immunization Division of the Texas Department of Health (TDH) say the most severe shortage to date has been the tetanus-diphtheria, or Td, vaccine. There also are shortages of the measles-mumps-rubella (MMR), diphtheria-tetanus-pertussis (DTaP), varicella (chicken pox), and hepatitis A vaccines, and of a relatively new vaccine, Prevnar, used to prevent pneumococcal disease.
And, it's not just childhood vaccines that are in short supply. The availability of flu vaccines has been limited during the past two winters. In 2001 some physicians paid up to 10 times the previous year's price for a vial of flu vaccine, says Gayle Harris, director of TMA's Public Health Department.
Some of the shortages were caused by production delays while pharmaceutical companies attempted to comply with Food and Drug Administration manufacturing practice guidelines. In the case of hepatitis A, vaccines manufactured as far back as 1999 were recalled because the potency had been diluted inadvertently. And DTaP vaccine production was slowed by the removal of thimerosal as a preservative because of concerns about the effect of mercury in thimerosal. The larger problem, however, is that many pharmaceutical companies are getting out of the vaccine business.
Brad Prescott, a Centers for Disease Control and Prevention (CDC) public health advisor assigned to the TDH Immunization Division, says problems with the Td vaccine began in December 2000 when Wyeth-Lederle announced it would stop producing it. Wyeth-Lederle supplied nearly a third of the national production of Td vaccine in 1999.
"That left only one manufacturer, Aventis-Pasteur, and they just weren't able to keep up," Mr. Prescott said. "There is one minor supplier, but they have a very limited production. Aventis is the only national producer."
Loss of manufacturers also has been partially responsible for shortages of the DTaP vaccine, given to infants and preschoolers. Infants get four doses before age 18 months and a fifth dose before entering school. Until 2000 there were four major manufacturers of that vaccine. Now there are only two.
In a recent article for Forbes.com, writer Ira Carnahan said the number of major vaccine manufacturers has dropped from 37 in the mid-1960s to only four today.
We're the Government and …
Public health officials hesitate to say why pharmaceutical companies are getting out of the manufacturing business, but Dr. Droge says vaccines just aren't big money-makers. "A lot of pharmaceutical companies are no longer participating in vaccine manufacture because it is not a profitable business," she said.
On the surface, that doesn't seem to make sense given the fact that millions of infants are born in the United States each year, creating a never-ending market for vaccines. And, about 75 million adults seek flu shots each year. With that kind of demand, you'd think pharmaceutical manufacturers would find the vaccine market a profitable one.
But Mr. Carnahan says the government has taken all the profit out of vaccines. Federal and state governments buy more than half of the country's childhood vaccines, he states in the Forbes.com article. But the government pays only a fraction of the price charged to private physicians and other health care professionals. The government pays only 60 percent of the market price for the DTaP vaccine and only 55 percent for the MMR vaccine. For others, the government pays as little as 38 percent of the market price, Mr. Carnahan says.
Tom Vernon, MD, vice president for policy, public health, and medical affairs for the Merck Vaccine Division, says a number of factors combine to make vaccine production a "fragile business," including intense government regulation and continuing concerns about liability. But he says government's control of the bulk of the vaccine market has been a huge disincentive for manufacturers to remain in the business.
"The price is less the problem than the signal to the industry, which is we are capping prices," said Dr. Vernon, a former Colorado health commissioner. "The function of government is to get the best possible fiscal deal it can get at any given time. Every year the drive is, 'Can it be cheaper? Can we spend less money? Cheaper, cheaper, cheaper,' to the point that vaccines are in essence commoditized.
"That is the situation when you have government buying a majority of vaccine, which is true across the United States, or in universal purchase states where the state actually buys the vaccine at the federal price for all the rest of the children, even for fully insured or wealthy children. That sends a signal to the industry that this is a place where you don't want to be," said Dr. Vernon.
Skipping the Booster
Regardless of the reasons, the shortages mean kids here in Texas and across the country aren't getting their shots.
The Td vaccine shortage forced TDH to recommend that Td boosters for adolescents -- required for school entry -- be put off for the present school year. TDH is still trying to determine whether an adequate supply of the vaccine will be available to give boosters for the 2002-03 school year.
Meanwhile, TDH is reserving its supplies of Td booster for wound management, says Judi Chase, program administrator for vaccine management in the Immunization Division. TDH buys vaccines through the federal and state Vaccines for Children programs and provides them to TDH regional offices, city and county health departments, and private providers who have enrolled in the program.
"We're following the CDC recommendations," she said. "Our main priorities are wound management and pregnant women who haven't been immunized."
Meanwhile, private physicians say they've had trouble getting the Td vaccine, as well. Madisonville family physician Andrew C. Eisenberg, MD, chair of the TMA Committee on Infectious Diseases, says physicians in outpatient clinics have been forced to send patients with cuts or other wounds to hospital emergency rooms to get Td boosters.
"Aventis was sending tetanus vaccine only to hospital ERs, not to outpatient facilities," Dr. Eisenberg said. "If people step on a nail, they don't necessarily go to the emergency room, they come here. But the company wouldn't send us the Td."
Shortages of the other vaccines have not been as severe. TDH officials say they have been able to ship enough vaccines to keep up with the recommended immunization schedules for DTaP and MMR. But Ms. Chase says TDH has had to juggle available vaccines to make sure the providers it supplies do not run short. For the DTaP vaccine, for example, TDH occasionally has had to cut shipments to some providers to as little as a two-week supply to stretch available vaccine.
So far, Ms. Chase says, TDH has had no trouble getting the MMR vaccine, but that is not the case with private physicians. Dr. Droge says her practice has experienced sporadic shortages of the MMR and varicella vaccines. She says she also was out of Prevnar for two months during the fall of 2001.
Ironically, the Prevnar shortages resulted because physicians and the public health community did better than expected in implementing the vaccine when it hit the market two years ago.
"There was a very rapid implementation throughout the country, one of the fastest start-ups of any vaccine that has been newly licensed," Mr. Prescott said. "The demand exceeded the manufacturing projections."
Getting Back on Target
When the vaccine shortages will be resolved is still an open question. Mr. Prescott says the remaining manufacturers are attempting to step up production to fill the gaps left by those who dropped out, but vaccine production is a lengthy process. Production time for the various tetanus vaccines, for example, is about 11 months.
CDC estimates that states can return to the recommended schedule for Td boosters by late 2002. A return to a full dosing schedule for the DTaP vaccine may not occur this year, CDC says. In January, the Advisory Committee on Immunization Practices (ACIP) recommended that physicians who do not have enough DTaP vaccine give priority to vaccinating infants with the first three doses, and defer the fourth dose for children between 15 and 18 months of age. If shortages continue, the fifth dose for children between ages 4 and 6 years also should be deferred, ACIP said.
Mr. Prescott says the news is better for the varicella and MMR vaccines, manufactured by Merck. The company estimates supplies of the chicken pox vaccine will be sufficient to return to the ACIP recommended schedule by late spring or early summer. And, shipping delays for the MMR vaccine of between 15 and 40 days were expected to continue only through March.
Meanwhile, vaccine shortages continue to hamper physicians' and nurses' efforts to improve Texas' immunization statistics. According to CDC statistics, only 69.5 percent of Texas children under 35 months of age have completed the recommended four doses of DTaP, three doses of polio vaccine, one dose of measles vaccine, and three doses of Haemophilus influenza type B vaccine to prevent Hib meningitis. Getting the kids who missed the recommended vaccines because of shortages or other reasons back into the doctor's office or clinic to catch up may be difficult.
"We're trying to keep reminder systems to try to notify families when the vaccines come in, but you always run the risk of some people not coming back if you don't vaccinate them while you have them," Dr. Droge said. "We're shooting ourselves in the foot, and it's beyond our control."
Ken Ortolon can be reached at (800) 880-1300, ext. 1392, or (512) 370-1392), or by email at Ken Ortolon.
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