Autumn will bring a strong pandemic wave which is likely to arrive earlier than the normal flu season in Europe, warn Angus Nichol and Denis Coulombier today. Writing in Eurosurveillance, the authors look ahead to how countries can best deal with the looming emergency by assessing how the first few weeks of the pandemic were handled on the continent.

 

“The European Centre for Disease Prevention and Control (ECDC) expects that in autumn European countries will experience a major first wave well beyond anything that has been experienced to date in this pandemic,” write Nichol and Coulombier, of the ECDC. “It is unlikely to occur at once and there will be heterogeneity within countries.”

 

European countries’ experience of the pandemic has already been mixed, note the authors. The majority of cases have been reported in Spain and the UK, with France and Germany having recently reported a high number. But all countries should anticipate a surge in the coming months, they say, which will “inevitably” strain health services.

 

Nichol and Coulombier single out the UK as the country with the highest number of people affected and the highest rates of virus transmission in Europe, with cases of severe and fatal illness “mounting up”. “Most infections are mild but there are steadily increasing numbers of people needing hospital care and more deaths are being reported.”

 

They looked for clues on how countries should handle the future wave of influenza by assessing the UK’s experience, and comparing response measures taken by the country to those adopted in North America.

 

At the early stages of the emergency, in May and June, the UK tried to stop influenza from spreading beyond small clusters or outbreaks of illness. This was done by actively tracking down and offering treatment with antiviral drugs to cases and their contacts in schools and families. In spite of these efforts, the daily number of laboratory-confirmed cases of ‘swine flu’ continued to rise, say the authors, prompting the country’s health authorities to reconsider the tactic.

 

On 2 July, the UK abandoned this ‘containment’ or ‘delaying’ strategy in favour of a ‘mitigation’ or ‘treatment’ strategy — essentially offering early treatment only to those at high risk of severe disease. This was adopted in North America from the outset, note Nichol and Coulombier, as advised by the World Health Organization.

 

Which of these approaches should European countries take when swine flu resurges? The authors suggest that delaying should be considered only when the country has seen only a handful of cases. “When confronted with more cases countries should consider whether to attempt delaying at all, what the advantages are of any time it might buy and the opportunity costs from what else will not be done as a consequence.”

 

Although delaying strategies could have kept the epidemic at bay for a while in the UK, working out how successful it has been is difficult and will take some time, explain Nichol and Coulombier. But for now, the country’s experience suggests these strategies can put public-health workers and laboratories under strain, making the task “impossible in any country given what is known now about the [virus’] effective reproductive number”.

 

Offering antiviral treatment aggressively and preventively early on in the outbreak, but not after the illness becomes widespread, can also send confusing messages to the public. Furthermore, people are less likely to complete a course of antiviral-drug treatment if they have mild symptoms or no signs of illness.

 

If delaying strategies are adopted, it is important to know when the time is right to activate mitigation strategies, note the authors. “There was... broad agreement based on the UK example that mitigation should be adopted either in the initiation phase or when acceleration starts... in individual countries.”