PROVIDENCE, R.I. - In response to increasing rates of meningitis over the past few years, Rhode Island public health officials recently recommended statewide meningitis immunization for everyone between 2 and 22 years of age.
Although the Rhode Island Department of Health (RIDH) and the Centers for Disease Control and Prevention (CDC) claim the increased number of meningitis cases do not represent an outbreak, a total of 125,000 doses of vaccine have been administered since late February when the RIDH adopted the new vaccination policy.
The state has purchased 275,000 doses of vaccine for Rhode Island practitioners to administer free to anyone in the specified age group; 248 clinics have already received 210,000 of those doses. The total estimated cost to purchase the vaccine is $5 million.
The amount of vaccine ordered by the RIDH is far less than the amount of vaccine used in outbreaks over the past four years. During 13 outbreaks between 1994-1997, just over 100,000 doses of vaccine were used, according to Bradley A. Perkins, MD, chief of the Meningitis and Special Pathogens Branch, CDC Division of Bacterial and Mycotic Diseases.
Although mass immunization of the population is not indicated at this time, RIDH Director of Health Patricia A. Nolan, MD, advised on Feb. 23 that all children and young adults 2 to 22 years receive meningococcal vaccine from their primary care providers during the next six months, unless they have been previously immunized in the last three years.
Robert Marshall, PhD, RIDH assistant director of health for community affairs, said at virtually the same hour of the announcement by Nolan, a 5-year-old child died of meningitis - the third death since Jan. 1.
By the next morning, the entire primary health care system in Rhode Island was in gridlock. Pediatricians and family practitioners' offices were overrun with phone calls and anxious parents demanding immunization for their children. It was at this point that the governor announced the state would help to establish community clinics to help meet the public demand for the vaccine, Marshall said.
Clinics have now been set up in public and parochial school gymnasiums, senior centers, hospitals and community centers and some have hours suitable for the working population.
The Advisory Committee on Immunization Practices (ACIP) guidelines for outbreaks state that vaccination should be undertaken once a specific case threshold is met. However, the RIDH recommended widespread vaccination despite that fact that epidemiological evidence did not indicate the need.
"I think it [mass vaccination] is an unfortunate public health response. This is a precedent that CDC and ACIP do not support," Perkins said. "It's a licensed vaccine and the RIDH knowingly deviated from the ACIP guidelines - not to willfully disregard them, but as a result of pressure from the public and medical community."
The average number of cases in recent years has jumped from 12-15 in 1994-95 to 24 cases reported in 1995-96 and 1996-97. Since Jan. 1, six cases in Rhode Island have been bacteriologically confirmed and five are still considered probable based on clinical data; three children, ages 2, 5 and 9 years have died.
Two cases since January have occurred in adults older than 40 and six cases in children 18 years or younger. Three 19-year-olds and one 20-year-old were also diagnosed with meningitis.
The reported cases have been caused by different strains of Neisseria meningitidis and are not linked, Marshall said.
As for the increase in sporadic cases of meningitis, Marshall said there is no identified reason, however the CDC stated peaks of meningitis cases occur in different locations throughout the United States each year.
The state is purchasing the vaccine with financial support from health insurers. All Rhode Island practitioners who administered meningococcal polysaccharide vaccine (Menomune-A/C/Y/W-135, Pasteur Mérieux Connaught) since Feb. 19 will be reimbursed.
Meningococcal vaccine is not universally recommended for routine administration by the ACIP because of its relative ineffectiveness in children under 2 years, which is the group at the highest risk for disease. The meningococcal polysaccharide vaccine also does not induce long-term immunity, nor does it protect against all serotypes of the disease.
Perkins said the conjugate serogroup A and C meningococcal vaccines in clinical trials were developed using methods similar to those used for the Haemophilus influenzae type b conjugate vaccine, and the efficacy of several experimental serogroup B meningococcal vaccines have been documented in older children and young adults.
Public health representatives from Rhode Island and surrounding states recently met with the CDC to discuss issues of conducting better control of meningococcal disease and working to implement early licensure and use of conjugate meningococcal vaccines, he said.
"The conjugate vaccine will be the best tool to fight this disease," Perkins said. "This could effect the early implementation of the conjugate vaccines."
Manufacturers currently working on meningococcal conjugate vaccines include Chiron Vaccines, Wyeth-Lederle Vaccines and Pediatrics, North American Vaccine and Pasteur Mérieux Connaught.
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