ACIP Backs Cholera, MenACWY Vaccines

Troy Brown, RN

June 24, 2016

The Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) has voted unanimously to recommend the CVD 103-HgR cholera vaccine (Vaxchora, PaxVax, Inc) for adults aged 18 to 64 years who are traveling to an area of active toxigenic Vibrio cholerae O1 transmission and who have an increased risk for exposure or poor clinical outcome if infected.

The committee also voted unanimously to recommend routine vaccination of HIV-infected persons aged 2 months and older with the meningococcal ACWY vaccine.

Cholera

Vaxchora is a live, attenuated, single-dose oral cholera vaccine. On June 10, 2016, the US Food and Drug Administration (FDA) approved the vaccine for use in adults aged 18 to 64 years traveling to cholera-affected areas. This is a new formulation of a previously approved cholera vaccine.

Cholera infection is caused by toxigenic V cholerae O1 (99% of cases worldwide) or O139. Infected individuals experience watery diarrhea that can be severe and rapidly fatal without treatment. Rehydration is a cornerstone of treatment and can reduce the fatality rate to less than 1%. The infection is endemic in more than 50 countries.

Cholera is uncommon among travelers but can be severe; most travelers to cholera-affected areas have a low risk for severe infection, and the committee does not recommend routine cholera vaccination.

Populations with a higher risk for infection include travelers visiting friends and relatives in an affected area who are unable to follow safe food and water practices and personal hygiene measures, and healthcare workers and response workers who have direct contact with bodily fluids from patients with cholera. Those who frequently travel to affected areas or who remain in such areas on a long-term basis may also have an increased risk as a result of cumulative exposure.

Travelers with a higher risk for poor clinical outcome if infected include those "who may be without rapid access to adequate rehydration and medical care” and those "with chronic medical conditions, including but not limited to travelers with conditions such as cardiovascular or kidney disease who would tolerate dehydration poorly."

The committee recommends that all travelers to affected areas should "follow safe food and water precautions and sanitation and personal hygiene measures as primary prevention strategies against cholera infection. Travelers who develop severe diarrhea should seek medical attention, particularly rehydration therapy, promptly."

Healthcare providers should carefully assess an individual traveler's risk for exposure or severe outcome if infected.

No data exist on the use of the CVD 103-HgR vaccine in pregnant or breastfeeding women; however, pregnant women are at increased risk for poor outcomes from cholera infection. Because the vaccine is not absorbed systemically, maternal vaccination is not expected to expose the fetus or breastfed infant to the vaccine.

There are no data on the use of the newer vaccine formulation in immunocompromised populations. A study of the use of the older formulation in HIV-infected persons in Mali found that the rate of vibriocidal seroconversion was slightly lower among HIV-positive patients compared with HIV-negative patients (58% vs 71%). There were no differences between vaccinated and comparison populations for any systemic adverse events.

There are no data on the use of the newer vaccine formulation in children; data on the use of the older formulation in children are limited.

The recommendation is a category A recommendation. The CDC director and the US Department of Health and Human Services must review and approve the recommendation, after which it will be published in Morbidity and Mortality Weekly Report.

Meningococcal Vaccine

The committee also voted to recommend routine vaccination with meningococcal ACWY (MenACWY) vaccine for HIV-infected persons aged 2 months and older.

The ACIP currently recommends routine vaccination of persons at increased risk for meningococcal disease. This group includes those with HIV, functional/anatomic asplenia or complement component deficiencies, and other chronic underlying illness. The risk for meningococcal disease among HIV-infected persons is increased fivefold to 24-fold; that risk is mostly due to serogroups C, W, and Y.

The incidence of meningococcal disease peaks among those in three age groups: infants and children younger than 5 years, adolescents and young adults aged 16 through 21 years, and adults aged 65 years and older. During the first 5 years of life, the incidence is highest among infants aged 0 through 5 months. Almost half (47%) of serogroup C and Y disease among children aged 0 through 59 months occurs during the first 6 months of life.

The committee was asked to vote on whether to recommend routine vaccination for HIV-infected persons aged 2 months and older (policy option 1) or to recommend routine vaccination for HIV- infected persons aged 11 years and older (policy option 2).

Including HIV-infected children aged 2 months to 10 years would be consistent with current ACIP recommendations for use of MenACWY vaccine in those with functional/anatomic asplenia or complement component deficiencies. Because the number of HIV-infected children in the United States is small, including this age group would not be burdensome or expensive. In addition, it is biologically unlikely that the increased risk for meningococcal disease in HIV-infected persons is different for children in comparison with adults. Research has shown that human serum bactericidal activity titers following one or two doses of MenACWY vaccine in HIV-infected children aged 2 to 10 years are higher than those in HIV-infected adolescents aged 11 to 24 years.

There are limited data documenting the burden of meningococcal disease in HIV-infected children in the United States. Depending on the timing of doses, vaccination of children aged 2 months and older may not entirely harmonize with ACIP/AAPs recommendations for use of MenACWY vaccines at age 11 to 12 years, and including them would mean that these patients would require multiple doses (primary series plus boosters) over their lifetimes.

The majority of the work group members are in favor of vaccination of HIV-infected persons aged 2 months and older.

"It's biologically implausible to me that children would have no increased risk when they're under 11 years of age. I hear people who say there's not a big disease burden or we don't have any data for children under 11 years of age, but it seems inconsistent with past and current policy to exclude a group," ex officio member Carol J. Baker, MD, professor of pediatrics, molecular virology, and microbiology, Baylor College of Medicine, Houston, Texas, said.

"From a programmatic point of view, I think there would be a lot of questions from the public that we would be excluding this group at risk, including those that are at greatest risk for meningococcal disease that we've discussed over and over, and those are children [younger] than 1 year of age [with] HIV infection. I've asked the committee at IDSA [Infectious Diseases Society of America], and we favor policy option 1," Dr Baker added.

The recommendation is a category A recommendation.

The committee voted unanimously to include MenACWY in the Vaccines for Children Program for infants and children aged 2 months and older. The Vaccines for Children Program is a federally funded program that provides free vaccines to children who might not otherwise be able to receive them because of inability to pay for them.

Trumenba Label Updated

The committee also updated changes to the dosage and administration section of the label of MenB-FHbp (Trumenba, Pfizer Inc) that were approved by the FDA on April 14, 2016. The ACIP is expected to vote on whether or not to recommend the changes at their October 2016 meeting.

The label originally recommended administration of three doses at 0, 2, and 6 months. That has been updated to recommend either a three-dose schedule (0.5 mL) at 0, 1 to 2, and 6 months or a two-dose schedule (0.5 mL) at 0 and 6 months. The label further recommends, "The choice and dosing schedule may depend of the risk of exposure and the patient's susceptibility to meningococcal serogroup B disease."

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....