The Health Information and Quality Authority (Hiqa) has found that mass thermal screening for coronavirus at airports is ineffective.
It is one of two evidence summaries published today to support the National Public Health Emergency Team’s (Nphet's) response to Covid-19.
The report “summarises the best available evidence on whether non-contact thermal screening could be used to effectively identify cases of Covid-19”.
Thermal screening detects radiating heat from the body to give an estimate of core body temperature.
Hiqa said in a statement that they identified “11 primary studies, three rapid reviews and one systematic review relating to Covid-19 and other respiratory virus pandemics.
“All studies were conducted in the context of points of entry (for example, airports), so their relevance to other community settings (such as schools) is uncertain.”
Hiqa said that the mass screening devices using non-contact devices “were not found to be effective in identifying infectious individuals and limiting spread of disease”.
They said that detection rates were consistently low across the studies.
“Thermal screening has been used in other respiratory infectious disease outbreaks, such as the 2009 H1N1 influenza pandemic in Asia and Australia, to improve detection and reduce the time to isolation of infected individuals,” said Dr Máirín Ryan, Hiqa’s Deputy CEO and Director of Health Technology Assessment.
“It typically involves a combination of fever screening, such as temperature testing, alongside self-reporting of exposure risk and or symptoms.
“However, the evidence clearly shows that this type of test is likely to be ineffective in limiting the spread of Covid-19.
“Thermal screening is noted to be high cost and resource intensive.
“Detection rates are very low due to large proportion of cases that have no symptoms, are infectious before showing any symptoms or who do not present with fever.”
Hiqa has also updated its evidence summary on the immune response, and potential immunity, following people being infected with the virus.
“It remains unclear whether long-term immunity to SARS-CoV-2 (the virus that causes Covid-19) is possible,” said Dr Ryan.
“SARS-CoV-2-specific IgG (immunoglobulin G) antibody was detected in nearly all individuals up to three months after they were infected, and over 90% of patients had developed a neutralising antibody response, which protects against viral infectivity.
“However, a handful of new studies suggest that it may be possible to be re-infected with SARS-CoV-2. HIQA will continue to monitor the evidence on immunity and update our summary as required.”
Hiqa said the evidence summaries were developed following requests from Nphet's Clinical Expert Advisory Group.