Concerns related to the testing of antibodies raised by academics and clinicians
Leading academics have voiced their concerns regarding the rapid deployment of the antibody tests.
Antibody tests Covid-19 may indicate if a person has had the disease in the past.
The first phase of the government programme of the antibody screening should assess the NHS and the nursing staff.
Clinicians can also request tests for patients in a hospital environment and be social if they deem it appropriate.
But a letter from academics and clinicians, published in The BMJ, raises concerns about the performance of tests, their clinical reasoning and their cost.
“We are writing to you to express your concerns about some aspects of the implementation of tests for the detection of antibodies anti-SARS-CoV-2 in England,” wrote the team of experts.
“The NHS England and NHS Improvement have written to trusts and networks of pathology in the NHS on 25 may 2020, asking them to propose tests of antibody in a short period of time and to increase the capacity of thousands of samples per day.
“We have three concerns regarding the application. First, there is no clinical indication for the test on an individual basis. Secondly, the performance of these tests have not yet been evaluated in relation to the standard generally required for a new test. And thirdly, the implications in terms of resources are not taken into account. ”
They stated that a test result is positive or negative would not change the management of a patient, and added that a positive outcome “does not indicate immunity”.
“The concept of” passport immunized “, allowing health care workers or other people work, has not been established. The persons whose antibody test is positive and must always be consider at risk and monitor the policies of infection control designed to prevent the nosocomial spread and risk of infection. Therefore, there is no advantage to the organizations of health care or for other to know the status of the employees at the present time. ”
They have also expressed their concerns about the “performance not proven” tests, adding: “The test is deployed at a pace and on a scale without precedent, without adequate assessment, which might compromise the public’s confidence in the pathology services in the future.”
The letter adds: “NHS England requires that the result is available within 24 hours. Given that the routine testing of patients are not clinically urgent or do not meet a clear need for public health, this tendency to introduce a test not factual for the uncertain gains of risk inefficient use of scarce resources.
The government website says: “while the results of an antibody test will not allow people to make changes to their behaviour, such as the relaxation of the measures of social distancing, it is clear that it is useful to know whether the NHS and social workers, and hospital patients and residents of care homes have had the virus, and in the collection of data on the results of the tests. ”
A spokesman for Roche Diagnostics UK has told the BMJ: “We use antibody testing to the NHS in the context of the next step, it is crucial to understand the spread of this virus, and provide greater confidence and greater assurance as we move into the next phase of our response to this pandemic. ”
A spokesman for Public Health England said: “Our assessments have been completed in a record time by using the samples and tests that we have. We are convinced that the volume of the samples and methodology were of a high standard. ”
In a statement to the BMJ, the department of Health and social Affairs said: “We do not know currently how long the antibody response to the virus, or if the fact of having antibodies means that a person cannot transmit it to others.”
But the spokesman reiterated that the test antibody “will play a role increasingly important as we move into the next phase of our response to this pandemic”.