de Boer PT, de Lange MMA, Wielders CCH, Dijkstra F, Schneeberger PM, van der Hoek W
RIVM Report 2017-0127
Between 2007 and 2010 there was a large epidemic of Q-fever in the Netherlands. In approximately two in 100 patients who have had Q- fever, the bacteria remain in the body. After months or even years, this can cause a serious disease to develop, i.e. chronic Q-fever. Chronic Q- fever occurs mainly in people with specific cardiovascular diseases, or who have a weakened immune system. If it is caught in time, these people can be treated with a course of antibiotics which has to be taken for at least eighteen months.
A number of civic groups have requested that a screening programme be set up so that people can be traced early before they become chronically ill. The National Institute for Public Health and the Environment (RIVM) has carried out an investigation to see if such a screening programme would be cost-effective. This would be the case for those groups at risk (people with a specific cardiovascular disease or a weakened immune system) who live in an area that was affected by the Q-fever epidemic. The screening of adults and elderly people who have no risk factors for chronic Q-fever is not cost-effective.
This study examined the costs and benefits of tracing chronic Q-fever in various groups of people. In this type of analysis, account is taken of the measure 'one year in perfect health', which is usually indicated by the acronym 'QALY' (Quality-Adjusted Life Year). Using this measure enables the effects of various treatments or preventative measures to be compared with one another. The calculations include looking at the costs (such as those of the study itself and of treatment) and benefits (such as improvement in health, fewer people with severe complications and the treatments required). The end result is the number of Euros that it costs to gain one QALY. This is then weighed against a sum of money up to which the programme could be regarded as being cost-effective.
Screening to trace patients at an early stage can also have disadvantages. For example, a false diagnosis of chronic Q-fever could be made. Also, it is not always clear if it is useful to start treatment or not. In addition, apart from causing worry it can also have damaging effects on the body, such as the side effects of the long-term use of antibiotics.