Us Airports: Coronavirus Screening And Safety Measures

In March 2020, 20 US airports were screening travellers for the novel coronavirus (COVID-19). However, the effectiveness of these screenings has been questioned, with some travellers reporting that they were not screened at all. While airport screening may help reassure the public, there is little evidence to suggest that these procedures are making a significant difference in containing the virus. Thermal screening, in particular, has been controversial due to its lack of accuracy in detecting the virus. The World Health Organization does not recommend thermal screening, stating that it offers little benefit while requiring considerable resources.

US airports screening travellers from China, South Korea, Italy, and Iran

In January 2020, several airports around the world began implementing preventive safety measures against the spread of the coronavirus. However, the effectiveness of thermal screening in detecting early signs of infection has been questionable.

In the US, airports are conducting entry screening for travellers from China and Iran. However, travellers arriving from Italy and South Korea are not being screened because those countries are conducting exit screenings.

The US Department of Homeland Security is working to raise the baseline for aviation security by requiring enhanced security measures at foreign airports with direct commercial flights to the US. These measures aim to prevent prohibited items and other threats to transportation security.

The Transportation Security Administration (TSA) incorporates unpredictable security measures, both seen and unseen, to accomplish its transportation security mission. TSA officers screen carry-on and checked baggage for explosives and other dangerous items. They also use advanced imaging technology and walk-through metal detectors to screen passengers for metallic and non-metallic threats, including weapons and explosives.

It is important to note that the World Health Organization does not recommend thermal screening as it is generally considered ineffective and resource-intensive. Instead, rapid identification and testing of suspect cases, contact tracing, and promoting behaviours that reduce the risk of transmission are more effective strategies to control the spread of the coronavirus.

Screening methods: filling out a questionnaire and temperature checks

In January 2020, several airports around the world started implementing preventive safety measures against the spread of coronavirus. These measures include filling out a health questionnaire and undergoing temperature checks.

Filling out a questionnaire

Some countries have introduced health questionnaires for incoming travellers. For example, in February 2020, Disney Cruise Line expanded its embarkation health questionnaire with additional questions regarding the 2019 Novel Coronavirus threat. Guests arriving at PortMiami to check in for a cruise were asked the following yes or no questions:

• Have you or any occupant of your stateroom travelled from or through China, including Hong Kong or Macau, in the past 14 days?
• Have you or any occupant of your stateroom had close contact with, or helped care for, anyone suspected or diagnosed as having Novel Coronavirus, or who is currently subject to health monitoring for possible exposure to Novel Coronavirus?
• Do you or any occupant of your stateroom have a fever (100.4ºF / 38ºC or higher), feel feverish, or have chills, a cough or difficulty breathing?
• Within the last 3 days, have you or any occupant of your stateroom developed symptoms of vomiting or diarrhea?

Temperature checks

Temperature checks, also known as thermal screening, have been implemented in many airports to detect signs of coronavirus-related fever. However, it is important to note that thermal screening has limitations and is not always effective at detecting early signs of infection. The World Health Organization does not recommend thermal screening, stating that 'it is generally considered that entry screening offers little benefit while requiring considerable resources'.

Methods of thermal screening include full-body infrared scanners, handheld infrared thermometers, and ear gun thermometers. Unfortunately, these methods have not been proven entirely accurate. There is a risk that they will flag passengers who have a different type of infection, while missing those who are truly incubating the virus but have not started to show symptoms yet.

Screening is ineffective at detecting early signs of infection

Thermal screening, which involves taking a person's temperature while they go through airport security, has long been controversial. While it can help to detect anyone with an elevated body temperature and, therefore, a possible infectious disease, it is not always effective at detecting early signs of infection.

Thermal screening was widely implemented during the 2003 SARS epidemic and later during the 2009 bird flu epidemic. However, it has its limitations. For example, it may flag passengers who have a different type of infection and miss those who are incubating the virus but haven't started to show symptoms yet.

The World Health Organization does not recommend thermal screening, stating:

> 'It is generally considered that entry screening offers little benefit while requiring considerable resources.'

The problem with thermal screening is that it relies on a person displaying symptoms of an infectious disease. However, many infectious diseases, including COVID-19, can be spread during the incubation period when the infected person is asymptomatic. The incubation period for COVID-19 is, on average, 5.2 days but can be as long as 14 days.

A study from the London School of Hygiene and Tropical Medicine found that, out of every 100 infected travellers taking a 12-hour flight, 42 would pass through both entry and exit screening undetected.

Even with more stringent measures in place, such as travel and quarantine restrictions, traveller screening will still miss more than half of people exposed to the virus, according to research by Katelyn Gostic, a postdoctoral researcher at the University of Chicago. Gostic studied how diseases like COVID-19 spread and how public health officials can try to contain them.

Gostic's research found that screening during flu season means that large numbers of people who are not infected with COVID-19 are probably being detained as false positives because the flu has similar symptoms.

Gostic also found that screening is ineffective early in the outbreak when we tend to rely on it the most. This is because, during the early stages of an outbreak, the vast majority of cases are going to have been exposed recently and probably won't have progressed to symptoms yet.

Billy Quilty, the lead author of the London School of Hygiene and Tropical Medicine study, said:

> 'Our work reinforces that thermal scanning cannot detect every traveller infected with this new coronavirus. Other policies that can decrease the risk of transmission from important infected individuals, such as providing information on rapidly seeking care if symptoms develop, are crucial.'

Screening can be beneficial in raising awareness

Screening at US airports can be beneficial in raising awareness about COVID-19. While it may not be the most effective method to prevent the importation of cases, it can help to delay the spread of the virus. This delay could be crucial in allowing medical professionals to develop more effective treatments or vaccines. Additionally, screening can help educate travellers about the symptoms of COVID-19 and encourage them to self-isolate and seek medical care if they start to exhibit symptoms. This is especially important in a culture where people tend to downplay their illnesses and continue their daily activities, potentially exposing many others to the virus.

The process of screening at US airports typically involves two parts. Firstly, travellers are required to fill out a short questionnaire regarding their travel history, any symptoms they may be experiencing, and their contact information. Secondly, CDC staff will take the travellers' temperatures using hand-held thermometers and observe them for any signs of illness, such as coughing or difficulty breathing. If a traveller is exhibiting symptoms, further evaluation may be conducted to determine if hospitalisation is necessary.

However, it is important to note that screening methods, such as thermal scanning, have their limitations. They may not always effectively detect early signs of infection, especially during the flu season when many travellers exhibit similar symptoms. Additionally, some individuals may be asymptomatic or exhibit mild symptoms, making it challenging for screening procedures to identify them as potentially infected.

To address these limitations, experts suggest implementing more stringent measures, such as travel restrictions and quarantine requirements. These measures aim to prevent the importation of cases and contain the spread of the virus. However, they also carry significant ethical, political, and economic implications, particularly if the epidemic persists over an extended period.

In conclusion, while screening at US airports may not be the primary mode of defence against COVID-19, it can play a crucial role in raising awareness and delaying the spread of the virus. The information provided during screening can empower travellers to make informed decisions and take appropriate actions if they develop symptoms.

Screening is unlikely to ever be a super-effective tool

Additionally, the symptoms of COVID-19 overlap with those of other illnesses such as the flu, allergies, the common cold, and asthma exacerbations, leading to a high number of false positives. The effectiveness of screening is further reduced by the possibility of mild or asymptomatic cases, which are challenging to identify through fever screening or questionnaires. Moreover, public health officials often lack specific and accurate questions to identify affected individuals, especially during the early stages of an outbreak when the mode of disease transmission is unclear.

Furthermore, screening all travellers is a massive undertaking that requires considerable resources. The World Health Organization has stated that entry screening offers little benefit and is generally not recommended. Instead, they suggest focusing on rapidly identifying and testing suspect cases, as well as tracing and monitoring close contacts of confirmed cases.

While screening can provide some benefits, it is crucial to recognize its limitations and complement it with other measures such as quarantine protocols, public health information campaigns, and strict adherence to hygiene and social distancing guidelines. These comprehensive approaches are more likely to be successful in controlling the spread of COVID-19.

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