What a flight between Dubai and Auckland tells us about coronavirus infections by plane

Negative pre-departure coronavirus tests are not enough: all passengers should be considered potentially infected upon arrival at their destination, especially on long-haul flights. The case of flight EK448 Dubai-Auckland

(photo: Getty Images) Negative tests before boarding would not guarantee Covid-free flights. A study published in Emerging Infectious Diseases, the journal of the US CDCs, puts on the table new evidence of coronavirus transmission during long-haul air travel, such as that between Dubai (United Arab Emirates) and Auckland (New Zealand).

Flight EK448

Flight EK448 departed from Dubai on 29 September 2020 and headed to Auckland was the focus of a small outbreak of Covid-19: despite all the passengers in possession of negative tests carried out before embarking, despite the distancing measures and personal protective equipment (only actually recommended) on board, 7 people then tested positive for the coronavirus and 6 became ill with Covid-19 during the 14 days of quarantine, mandatory in New Zealand.

What happened? Who did the infection start from and where did it come from? The international team of researchers led by Tara Swadi of the New Zealand Ministry of Health tried to find an answer to these questions, which analyzed the movements and the genome of the coronavirus extracted from the biological samples of the 7 passengers to trace the source of the infection and understand if the transmission had actually taken place in the 18 hours of flight that separate Dubai from Auckland.

Travel

The 7 passengers (A, B, C, D, E, F, G) came from 5 different countries before coming to Dubai to board the same flight to Auckland . All, as per protocols now adopted internationally, had tested negative for the coronavirus within 72 hours of departure and 5 of them had repeated the test in Malaysia. On board the plane they were all seated a few rows away for an 18-hour flight. Two of them decided not to wear masks and gloves (recommended but not mandatory).

(image: diagram of the position of positive passengers on board / Swadi et al, 2021)

The genome

By sequencing the entire coronavirus genome in the 7 passenger samples, the researchers found that the sequences were identical to each other, with the exception of a single mutation in one of the passengers. A clue that the infection probably had actually occurred during the flight. By comparing the sequences with those contained in the Gisaid database, the scientists found 6 other identical genomes: 4 registered in Switzerland and 2 in the United Kingdom.

The origin of the outbreak

In light of these information, the team thinks that the source of the infection was passenger A, the first to show symptoms of Covid-19 during the quarantine in New Zealand, who left Switzerland together with passenger B, who tested positive for infection a a day away. The virus would then spread on the plane, infecting 4 other people. Passenger G, on the other hand, allegedly contracted the coronavirus during quarantine, from his travel companion F.

(image: the provenance of positive passengers / Swadi et al, 2021) However, the researchers admit, it is not Absolute certainty is possible due to gaps in sequencing data globally. In other words, the virus may not come from Switzerland and may have been introduced by another passenger from another country where, however, this genome has not yet been found or has not been registered on the database. Or again, one of the passengers may have become infected during the stopover at Dubai airport, where personal protective equipment was not mandatory.

In any case, the authors conclude, the study demonstrates the validity of the New Zealand model which still continues to consider travelers, despite all security measures, as potentially infected, and therefore forced to quarantine.


Finance - 2 hours ago

How much did Zoom's revenue grow in 2020

adsJSCode ("nativeADV1", [[2,1]], "true", "1 "); Medicine - 3 hours ago

Clinical tests of Takis' Italian Covid vaccine begin. What does it mean?

adsJSCode ("nativeADV2", [[2,1]], "true", "2"); Social Network - 4 hours ago

Twitter has started to fight disinformation about vaccines against Covid-19

Topics

Coronavirus Health Travel globalData.fldTopic = "Coronavirus, Health , Travel "

You May Also Interest

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.