Invasive meningococcal disease: Public Health Ontario research highlights consequences and importance of vaccination
Invasive meningococcal disease can be severe and life-threatening. Two recent studies by PHO authors looked at this disease and highlight the importance of vaccination.
The first study, The Health Burden of Invasive Meningococcal Disease: A Systematic Review, looked at the after effects of invasive meningococcal disease (IMD). Although IMD is rare, the disease continues be a threat to human lives and negatively affects survivors’ quality of life. Common reported consequences of IMD, aside from death, were hearing impairment, cognitive impairment, and psychological problems. In general, children with IMD had a greater incidence of hearing loss and psychological disorders, including attention-deficit/hyperactivity disorder.
This study is important for clinicians who need to be aware of the frequency and potential impact of longer-term consequences of IMD to ensure appropriate investigations and follow-up past the acute phase. “A better understanding of the full spectrum of effects is critical for assessing the burden of disease and supporting health care planning and decision-making given new vaccines,” said Dr. Beate Sander, senior author of the study.
The second study, Epidemiology of serogroup C and Y invasive meningococcal disease (IMD) in Ontario, 2000-2013: vaccine program impact assessment, looked at the population-level impact of the Ontario vaccination program for IMD strains C and Y. The authors looked at 14 years of data and two kinds of meningococcal vaccines, a vaccine preventing C disease strains, introduced in 2004 for one year olds and grade seven students, and a quadrivalent meningococcal vaccine for strains A, C, Y and W, which replaced the C vaccine for grade seven students in 2009.
They found that the incidence of C disease strains decreased significantly over time, particularly in children after introduction of the vaccination program in 2004. There was also a reduction in Y disease strains throughout the 14-year study period, and a decrease among adolescents after the quadrivalent vaccination program was introduced in 2009.
The authors noted that the clear reductions in C disease strains suggest that the program provided both a direct impact and a herd effect, giving protection to those not immunized. Continued surveillance of this disease in Ontario is important to assess program impact of the quadrivalent vaccine.
“Although rare, we continue to see invasive meningococcal disease in the province,” said Dr. Shelley Deeks, a co-author of both studies. “The study suggests that Ontario’s IMD vaccination programs have reduced rates of IMD. It’s important that children are vaccinated at age one and in grade seven to protect against both the immediate and long-term consequences of this disease.”
More information on both studies:
Strifler L, Morris SK, Dang V, Tu HT, Minhas RS, Jamieson FB, Deeks SL, Crowcroft NS, Sander B. The Health Burden of Invasive Meningococcal Disease: A Systematic Review. Published online October 15, 2015. Journal of the Pediatric Infectious Diseases Society.
Wormsbecker AE, Wong K, Jamieson FB, Crowcroft NS, Deeks SL. Epidemiology of serogroup C and Y invasive meningococcal disease (IMD) in Ontario, 2000-2013: vaccine program impact assessment. Published online August 20, 2015. Vaccine.