The level of herd immunity before and after the first 2009 pandemic season is not precisely known, and predicting the shape of the next pandemic H1N1 season is a difficult challenge. Carrat, et al. (2010) conducted a modeling study based on data on medical visits for influenza-like illness collected by the French General Practitioner Sentinel network, as well as pandemic H1N1 vaccination coverage rates, and an individual-centred model devoted to influenza.
The researchers estimated infection attack rates during the first 2009 pandemic H1N1 season in France, and the rates of pre- and post-exposure immunity. They then simulated various scenarios in which a pandemic influenza H1N1 virus would be reintroduced into a population with varying levels of protective cross-immunity, and considered the impact of extending influenza vaccination.
During the first pandemic season in France, the proportion of infected persons was 18.1 percent overall, 38.3 percent among children, 14.8 percent among younger adults and 1.6 percent among the elderly. The rates of pre-exposure immunity required to fit data collected during the first pandemic season were 36 percent in younger adults and 85 percent in the elderly. The researchers estimated that the rate of post-exposure immunity was 57.3 percent overall, 44.6 percent in children, 53.8 percent in younger adults, and 87.4 percent in the elderly. The shape of a second season would depend on the degree of persistent protective cross-immunity to descendants of the 2009 H1N1 viruses. A cross-protection rate of 70 percent would imply that only a small proportion of the population would be affected. With a cross-protection rate of 50 percent, the second season would have a disease burden similar to the first, while vaccination of 50 percent of the entire population, in addition to the population vaccinated during the first pandemic season, would halve this burden. With a cross-protection rate of 30 percent, the second season could be more substantial, and vaccination would not provide a significant benefit.
The researchers conclude that model-based findings should help to prepare for a second pandemic season, and highlight the need for studies of the different components of immune protection. Their research was published in BMC Infectious Diseases.
Reference: Carrat F, Pelat C, Levy-Bruhl D, Bonmarin I and Lapidus N. Planning for the Next Influenza H1N1 Season: A Modelling Study. BMC Infectious Diseases 2010, 10:301doi:10.1186/1471-2334-10-301.
Dear Helpdesk: Working in a Toxic Health Care Environment
March 28th 2024Dear Helpdesk is your steadfast companion, offering life coaching and workplace advice from 2 seasoned IPs for some of your most challenging real-life situations. Let us help you navigate the intersection between work and life, guiding you to navigate the dynamic world of infection prevention with confidence and grace. This article is on handling a toxic health care environment.
Product Locator: Spring and Early Mother's Day Gift Guide for Infection Prevention Personnel
March 27th 2024Whether it's a spring holiday, birthdays, or no reason at all, infection prevention personnel love to give and receive gifts that help at the end of a stressful day. Infection Control Today® offers some gift ideas for infection prevention personnel and their families.
Catching Up With Vangie Dennis, AORN 2022-2023 President at AORN 2024
March 26th 2024Infection Control Today (ICT) had the privilege of catching up with Vangie Dennis, MSN, RN, CNOR, CMLSO, at the Association of periOperative Registered Nurses' (AORN’s) International Surgical Conference & Expo 2024. As the former president of AORN and an esteemed figure in perioperative services, Vangie Dennis shared insights into her recent endeavors and the exciting new chapter she's embarked upon.
How To Optimize Your Time Management Strategies for the Busy Infection Preventionist
March 25th 2024Is your calendar resembling a chaotic masterpiece of overlapping tasks? Join the club of infection preventionists striving to balance responsibilities. Dive into proven strategies from a fellow infection preventionist to reclaim control of your time, streamline tasks, and boost productivity effectively. This is an IP Lifeline article.