An outbreak of 59 cases of Covid-19 across the country originated after 13 people, including a one-year-old child, contracted the disease on an international flight into Ireland over summer.
The passengers were on the same flight, each having transferred via an international airport, flying into Europe from three different continents. The virus then spread to 46 other people afterwards.
A study by Eurosurveillance, a medical journal published by the European Centre for Disease Prevention and Control, discovered the laboratory-confirmed cases in six of the eight different health regions throughout the country. The seven-and-a-half-hour flight had a passenger occupancy of 17pc (49 of 283 seats) with 12 crew.
The research paper refers to the passengers as Groups 1, 2, 3 and 4 and states Group 1 reported spending up to 12 hours overnight in the transit lounge during stopover; Group 2 shared a separate transit lounge while Group 3 and Group 4 had separate short waits of under two hours in the general airport departure area.
The age of the 13 cases, states the report, ranged from one year old to 65 years old, with a median age of 23 years.
The report noted how following the flight, the earliest onset of symptoms occurred two days after arrival. The latest case in the entire outbreak occurred 17 days after the flight.
« Of 12 symptomatic flight cases, symptoms reported included cough, coryza, fever and sore throat, and six reported loss of taste or smell, » according to the report. « No symptoms were reported for one of the passengers, » it said.
A national outbreak control team was then convened with involvement of Departments of Public Health and National Focal Point « to investigate, identify and interview cases, oversee contact tracing and establish control measures ».
« Close contact passengers were defined as two seats in every direction from the first cases notified. They were initially traced and the cabin crew were risk-assessed to establish whether they would be classified as close contacts of the cases or whether they had any illness, » the study found.
As transmission emerged, close contacts on the flight for the first eight presenting cases were identified. Nine reachable contacts tested negative while « five further symptomatic positive cases were confirmed ».
An additional 15 passengers tested Covid-19 ‘not detected’, one passenger declined testing, and the remaining 11 passengers were not contactable.
« No data was available for these 11 passengers or for the crew with regard to symptomatology and subsequent illness. As a result of the risk assessment, crew members were advised to quarantine for 14 days. A ‘warn-and-inform’ letter was sent to all passengers, » it said.
The study also found exposure possibilities for these cases include in-flight, during overnight transfer/pre-flight or unknown acquisition before the flight.
« The incubation period for Covid-19 may be as short as two days, so the potential for in-flight/airport transmission exists in this outbreak. »
Compiled by medical professionals, the report makes a number of recommendations including « when a positive case is linked to a flight, rapid flight contact tracing may prevent onward spread ».
Last night a HSE spokeswoman said: « Given the current domestic and international situation, the safest thing to do is not to travel abroad. »
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Disease outbreak, Virus
World news – GB – Thirteen people infected on a flight led to 59 cases