[Table of Contents]

Volume: 25S5 - August 1999

Proceedings of the National Varicella Consensus Conference
Montreal, Quebec
May 5-7, 1999

Research Needs

Participants identified a number of research needs and priorities related to varicella, outlined below. It was also recommended that these priorities be brought to the attention of appropriate funding bodies so that research funds can be made available to address them.

• General immunization issues, such as the need for booster doses and waning immunity, should be addressed.
• Studies should be done to assess the molecular epidemiology of VZV strains in Canada.
• Mechanisms of and susceptibility to VZV embryopathy should be defined.
• Models should be used to predict when surveillance systems should shift from aggregate to case-by-case reporting and when special studies should be done for case investigation. Surveillance data should be periodically fed back into the models to improve their predictive capacity.
• Appropriate and safe immunization strategies should be determined for immunocompromised patients, including HIV-infected persons; cancer patients in remission; solid organ transplant recipients; bone marrow transplant recipients; patients with hypogammaglobulinemia; leukemia patients (e.g. whether to immunize 3 months after treatment, and the role of acyclovir); persons with chronic lung disease (e.g. cystic fibrosis); and other immunocompromised individuals, such as those receiving cyclosporine treatment.
• Studies should be done to determine the potential for early use of vaccine in anatomically compromised individuals (e.g. persons with pulmonary conditions or skin disease); persons with chronic heart disease; and pre-operative cases (for elective surgeries).
• History and serologic status of health care workers should be investigated to establish (1) a Canadian profile among the age groups in this population; (2) the benefits of booster vaccine, if any; and (3) the potential need to revise the definition of health care worker with respect to potential work exposure.
• Epidemiologic studies should be undertaken to determine whether any of the following groups are at higher risk and should be identified as priorities for specific immunization strategies: aboriginal persons (e.g. whether aboriginal children are at higher risk of complications from varicella, whether invasive group A streptococcal infections are more common, whether children are at risk for missed vaccination opportunities because of relocation); homeless persons; and immigrants (e.g. seroprevalence information to determine endemicity from country of origin).
• Special studies in pregnant women should be carried out to determine how many times a pregnant woman should be screened; the loss of immunity; and prospective (anonymous) varicella prevalence among pregnant women or babies.

[Previous] [Table of Contents] [Next]