Concluding remarks:
We used the various online sources along with the data from government
organizations for ten countries to screen the flights and passengers
form 24 airports connecting various international airports in India. As
of 4th March 2020 India, has started the thermal
screening of passengers arriving from 12 countries, viz. China, South
Korea, Japan, Italy, Iran, Singapore, Thailand, Malaysia, Hong Kong,
Vietnam, Nepal, and Indonesia. It is, however, not clear if the
passengers either travelling and/or transiting through any of the
airports form middle east, especially Dubai, were also being subjected
to thermal screening. If that was not the case, it is very important to
mention that non-screening of passengers arriving through larges transit
hub like Dubai (DXB) could have remained undetected, which later on went
on to become infected. On the other hand, the stamping of the passengers
initiated by authorities in India came as one of the most effective
steps, as long as it was stringently executed by authorities and
followed by passengers for the self-quarantined for the mentioned
period. We strongly emphasize that this was one of the most effective
way to contain the spread due to importation of the infected passengers
in two following ways. a. a full database of the passenger is obtained
at the time of the screening, and b. it is much easier and feasible to
track the very same passenger for next 14 days, which is the advisable
quarantine period. Such a screening and additional measures like
stamping need not be restricted for the passengers arriving only from
largely affected countries but must be extended to the passengers coming
from large transit hub in future. For example, at the time of initiating
the thermal screening for the passengers arriving from Singapore, there
were not many cases registered in Singapore or other east Asian
countries. As per our understanding such a measure was implemented
primarily to identify the passengers arriving from China, which was
epicenter of pandemic, transiting through one of the east Asian
countries particularly Singapore airport. Overall, we believe that the
effective measures taken by the government and authorities at various
international airports in India were adequate and effective although
they were restricted only to the passengers arriving from largely
infected countries. We, however, also note that the screening and
quarantining of the passengers arriving from major transit hub could
also have been strictly implemented from the very beginning.
It is very important to note that analyses presented here involve the
modeling and estimation based on combination of various different data
sources. Under such a situation, where large datasets from various
sources is combined to derive certain index requires lot of assumptions
to consider and pose various limitations. All these simulations and
subsequent estimation heavily rely on the accuracy and reasonable
assumption of passenger seats and flight data. In this way, we are not
aware of any particular methodology to validate our model, except that
comparing the derived importation risk index with actual number of
passengers, which for our study is in good agreement. Nevertheless, our
results provide data and methodology, which in a nominal way could be
used for effective measures and mitigation policies to be implemented at
travel hubs for effective containment of travel related risk of
infections.