Page 146 - Timeliness of Infectious Disease Notification & Response Systems - Corien Swaan
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144 Chapter 6
Regarding the awareness of ILI symptoms, Schiphol Airport handed all passen- gers on flights arriving from Mexico information leaflets on influenza A/H1N1 2009 with information on early symptoms and requesting them to seek medi- cal advice in case of fever and respiratory symptoms such as coughing. Posters with this information were placed in passenger halls, to inform passengers arri- ving indirectly from Mexico via transit through other airports, or arriving from non-endemic areas with higher transmission (e.g. USA). As contact details were identified on average 3.9 days after exposure, however not contacted yet, we conclude that CT did not have additional value for timely achievement of incre- ased awareness.
It is not a new finding that contact tracing of flight passengers is a time-con- suming procedure [8]. In one study among flight passengers during the pan- demic in 2009, 52% (53/95) of the contacts were reached within 72 h [5]. In a measles contact investigation, 75% (202/275) of responding passengers were contacted within 72 h. In this study however, the diagnosis of measles was al- ready suspected during the flight, and laboratory confirmation was initiated immediately after landing [19]. It also helped that many contacts were tourists staying at the same hotels, which facilitated tracing them.
Our study shows that the longest delay before identification of contact de- tails for an influenza index case is caused by the time between arrival and labo- ratory diagnosis (interval I, 2.6 days). This delay is a result of patients delay in seeking medical care, and doctor’s delay, including laboratory confirmation. For influenza, the indicated laboratory test was Polymerase Chain Reaction, which takes several hours to obtain the result and in the beginning of the pandemic, the PCR test was not yet available in many laboratories.
Patients delay was considerable however. It even took the seven passen- gers with date of onset before the flight, and therefore symptomatic during the flight, 1 to 2 days after arrival before laboratory confirmation was made. Also, none of the airline reported that these patients already were identified during the flight, nor that infection control measures were taken. For the indexes that became ill on the day of arrival, delay until laboratory confirmation still lasted 3 days (range 1–6 days). A pre-pandemic study by Sharangpani et al. among flight passengers showed that they are more willing to seek physicians care in case they developed flu-like symptoms when they perceived the pandemic as seri- ous. [20] Leggat et al. demonstrated during the pandemic that only a minority (35.5%) of Australian citizens would cancel their air travel in case of cough and fever lasting more than 1 day. This was higher among persons who were more concerned about the pandemic [21]. In the Netherlands, the perceived severity
     





























































































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