How proportionate is the pandemic response?
Dr Robert Verkerk raises questions about the new flu outbreak and how to respond to it
No one doubts the suffering that some have experienced due to the current outbreak of new influenza A(H1N1), formerly referred to as ‘swine flu’. But in the context of many other human diseases, the media reaction to the disease, as well as the international coordination of responses by governments, the pharmaceutical industry and vaccine manufacturers seems somewhat disproportionate.
To put it in context, in sub-Saharan Africa at least a million people die a year from malaria – the mortality figures average out at around 3,100 people each day. Worldwide, ordinary seasonal influenza causes 3 to 5 million cases of severe illness each year and kills between 250,000 and 500,000 people annually.
Since the new strain of H1N1 was found to be spreading rapidly in Mexico in April, causing sometimes severe symp- toms or even death in persons primarily under 60 years of age, the World Health Organization (WHO), as of 29 May, has been able to confirm 15,510 cases – but just 99 deaths (0.6%). In the case of the vast majority of confirmed infections of ‘new influenza’, the symptoms have been mild and present no threat to life at all.
When you look at the pattern of deaths compared to the spread of the virus, it’s clear that the virus is spreading, yet causing a declining death rate, which appears to have settled, at least for the time being, at a around half a percent of those infected (Fig 1). This is a common pattern in epidemics. The greatest virulence often occurs in the early stages – then it tends to peter out. While the majority of infected persons have so far suffered only mild ‘flu symp- toms, one shouldn’t become complacent. A mutation or reassortment of the virus may yet cause significant death and dis- tress. However, there is no evidence yet of any such change to the virus.
We should not forget that this virus’ close relative, the avian-derived H1N1 virus that causes mostly non-lethal, sea- sonal influenza, originally caused between 25–50 million deaths during the ‘Spanish flu’ of 1918–20. In the 90 years since its first outbreak, its virulence has never returned to the levels found in the early waves of infection in humans. Will it be any different for the new subtype?