Influenza Incidence, Severity and Impact Conference #isirv

Last week I was at the Institut Pasteur in Paris for the conference on Incidence, Severity and Impact of Influenza. The conference was organized by the Epidemiology Subgroup of the International Society for Influenza and Other Respiratory Viruses (ISIRV). The subgroup’s remit, though still developing, is to coordinate activities around influenza epidemiology, and the conference is an opportunity for researchers and policymakers worldwide to provide updates on these activities.

2016-01-21 08.34.39

Although there was not much in the way of new data presented at the conference, a few things stood out for me. A major challenge in studying influenza is that most systems to track the progression of seasonal and pandemic strains rely on data from hospital admissions or other healthcare encounters. This is useful, but only part of the story, as most people who acquire influenza do not seek medical treatment. Our understanding of how much illness and transmission occurs in the community is, in most places, very limited. There was an overview of recent and ongoing community-based studies of influenza from the UK, New York City and Nicaragua, in which participants are recruited from the community to report symptoms on a regular basis and provide samples for laboratory testing of influenza.

There were also reports from two studies in South Africa and Malawi addressing influenza in HIV-infected individuals. These studies compared severe (hospitalized) influenza cases and mild (non-hospitalized) influenza cases, finding that HIV infection was much more common among hospitalized patients. There are some methodological limitations to this type of study (for example, HIV patients are generally more likely to use hospital services, and so might be more likely to be diagnosed with influenza in hospital relative to other healthcare settings), but nonetheless, as antiretroviral treatment becomes more widely available and the number of people living with HIV increases, this raises the potential for an increased burden of influenza in this population. It also raises important policy questions. HIV patients are a target group for influenza vaccination, but in many low and middle-income countries, influenza vaccine supplies are limited. The question of how to prioritize limited stocks and which groups should receive influenza vaccine is very relevant and much more work is needed in this area.

Leave a Reply

Your email address will not be published.

Back To Top
Skip to toolbar