Meningococcal Disease in Pilgrims

Disease Update

Synopsis: Since the outbreak of Neisseria meningitides infections that occurred in Hajj pilgrims in 1987, Saudi Arabia has required pilgrims to be vaccinated with the bivalent meningococcal A/C vaccine. In recent years, outbreaks of meningococcal disease associated with pilgrims to the Hajj have shifted from serogroup A to W135. Saudi Arabia has changed the policy for the 2002 Hajj season to require that all pilgrims be vaccinated with the quadrivalent meningococcal vaccine.

Source: Memish ZA. Meningococcal disease and travel. Clin Infect Dis. 2002;34:84-90.

A large and serious outbreak of serogroup a meningococcal disease associated with the Hajj occurred in 1987. The outbreak led to a requirement that pilgrims traveling to Saudi Arabia be vaccinated with the meningococcal vaccine. Following the institution of this requirement, small outbreaks of meningococcal diseases still occurred in Mecca and Jidda, mainly in unvaccinated persons. Following the Hajj in 2000, an outbreak involving predominantly W135 was identified. It affected at least 330 pilgrims and their contacts in numerous countries.¹ (See prior review in TMA Update July/August 2000;10(4):29-30.) In 2001, more than 150 cases of meningococcal disease were identified in the period following the Hajj, with greater than 50% attributed to serogroup W135.²

As a result of the shift to serogroup W135 predominance, the Ministry of Health of Saudi Arabia is instituting a change of policy for the Hajj in 2002. All local population at risk will be vaccinated with the quadrivalent vaccine. Moreover, all pilgrims must be vaccinated with the quadrivalent meningococcal vaccines. The vaccine needs to be administered at least 10 days before and not greater than 3 years prior to arrival in Saudi Arabia. Children 3 months to 2 years old should receive 2 doses of the vaccine separated by a 3-month interval.³

The transmission of meningococcal disease to contacts by vaccinated pilgrims demonstrates the failure of the polysaccharide vaccine to eliminate N meningitides carriage in vaccinees. Furthermore, while the serogroup A and C polysaccharide vaccines have a clinical efficacy of 85-100% in older children and adults, the serogroup C polysaccharide is ineffective in children younger than 2 years of age.⁴ The efficacy of serogroup Y and W135 polysaccharides is less clear. Newer vaccines such as the meningococcal conjugate vaccines hold promise for improved protection and should become available within the next few years.

To assess pharyngeal colonization in pilgrims after returning from Saudi Arabia, the Centers for Disease Control and Prevention (CDC) performed a study in 2001. The carriage of W135 was found to be similar between pilgrims and nonpilgrims.⁵ Therefore, the CDC does not recommend prophylactic antibiotics for returning pilgrims.

On the other hand, prophylactic medication after close-case contact (household, day care center, exposure to patients’ oral secretions) should be given within the first 24 hours of exposure. For adults, the recommended antibiotic is one oral dose of ciprofloxacin 500 mg or ofloxacin 400 mg or azithromycin 500 mg. For post-exposure prophylaxis in children, rifampin can be given at 5 mg/kg every 12 hours for 2 days in those younger than 1 month old, and 10 mg/kg every 12 hours for 2 days in those older than 1 month old. In children younger than 15 years of age, a single dose of ceftriaxone 125 mg IM is an alternative prophylaxis.

There is one meningococcal vaccine available in the United States, and that is the quadrivalent vaccine containing polysaccharide to serogroups A, C, Y, and W135 (Menomune). A serogroup A/C polysaccharide vaccine has been used outside of the United States, and a conjugate serogroup C vaccine has been available in the United Kingdom. Because of the change requiring the quadrivalent vaccine for pilgrims to Saudi Arabia, the immunization records of travelers should clearly reflect the administration of the quadrivalent A, C, Y, W135 vaccine. In addition to providing the immunization, a discussion of postexposure prophylaxis would benefit the travelers.

References

1. World Health Organization. Meningococcal disease, serogroup W135—update. Available at www.who.int/emc/outbreak_news/n2000/may/12may2000.html.

2. World Health Organization. Meningococcal disease, serogroup W135 (update). Wkly Epidemiol Rec. 2001;76:213-214.

3. World Health Organization. Meningococcal disease, serogroup W135. Wkly Epidemiol Rec. 2001;76:141-142.

4. Rosenstein NE, et al. Meningococcal vaccines. Infect Dis Clin North Am. 2001;15:155-169.

5. CDC. Update: Assessment of risk for meningococcal disease associated with the Hajj 2001. MMWR Morb Mortal Wkly Rep. 2002;50:221-222.

Published: February 2002