expert comment about COVID-19 testing issues

expert comment about COVID-19 testing issues


Journalists have asked for comment on the current COVID-19 testing issues being discussed in the media. 


Prof Gordon Dougan, Department of Medicine, University of Cambridge, said:

“Having personal experience of setting up a testing service for health care workers in real time I appreciate the complexities and challenges which are practical, logistical and ethical.  It is vital that testing results get back as quickly as possible, normally within 24h if they are to be useful to prevent further disease transmission.  This is particularly important in settings such as hospitals and care homes where asymptomatic carriers can infect vulnerable people.

“The current national testing system is was put together at short notice and is centralised involving multiple partners.  Many inexperienced groups are involved and facilities have been set up ad hoc.  Despite valiant efforts the system is not robust and is vulnerable to failure at multiple levels; practical (equipment, reagents), logistical (trained personnel) and ethical (the need to return data promptly . Also any system needs to be transparent and trusted with independent validation.  It helps if local communities are involved who know their ground and people.”


Dr Stephen Griffin, Associate Professor in the School of Medicine, University of Leeds, said:

“The current inadequacies of community testing run the risk of us getting seriously behind in terms of the recent resurgence of SARS-CoV2 infections across the entire UK.  Estimates that infections are doubling approximately every seven days are likely to now be somewhat out of date, yet we are currently flying blind with respect to how the epidemic is evolving in the community.

“Worryingly, it has not been made clear exactly where the bottleneck in providing new tests lies, merely that the increased demand for community testing is currently overwhelming the system taking weeks to rectify.  It is astonishing that proper provision was not made during the summer, especially given that the Government has been consistently advised that the autumn and winter posed a considerable risk for increased virus transmission.

“Moreover, the government has a duty of care to ensure the safe return of schools, universities and workers, especially as they have promoted considerable social mixing in bars, pubs, restaurants and travelling abroad, all whilst mystifyingly “pausing” the shielding scheme.  Testing and tracing is currently the best means to achieve this safe return, yet capabilities are sorely lacking.  If the private contractors engaged in this activity are unable to deliver – although it is unclear whether that is the problem or not – then it’s possible redirecting investment into our NHS public health system might deliver more favourable outcomes.

“It is imperative that testing and tracing is not only restored, but improved immediately, or we may start to pay a severe price if hospital admissions and the incidence of severe disease increase.  It would seem prudent that, rather than aiming for the moon, perhaps the government might consider placing both feet firmly on the ground by properly establishing the fundamentals of test and trace.”


Dr Joshua Moon, research fellow in the Science Policy Research Unit at the University of Sussex Business School, said:

“The current issues with testing have a mixture of implications.  The first point is that a lack of testing is clearly going to impact what cases are found, but the more important question is which cases.  A lack of testing capacity means that testing resources will need to be targeted in some way.  The way this is done will affect what cases slip through the net.  Reports coming back to us show that ordering a test requires filling out a ‘reason’ for ordering a test which seems to be allocating some sort of priority (those with symptoms, essential workers, etc.).

“Second, with a large number of tests being missed we are likely to be missing a vast number of contacts too.  By missing these contacts we have to worry about what is going on unseen by the testing system.

“Some reports have come out talking about issues in the viability of tests, with particular focus on issues with the Randox tests.  This is worrying given that Randox tests are frequently used in care homes so missing cases in that context is very worrying.

“One of the deeper issues, however, is why we are seeing an acute shortage when total tests per day currently sit at two thirds of the government’s claimed testing capacity.  I am particularly worried about why the claimed capacity was so much higher than it actually was.  Without proper understanding of the system’s capacity, there is a fundamental weakness in ability to plan for the future.  If we expect to have capacity (as we did) and see a sudden spike in cases that overwhelm capacity far below our expectations (as we did) then we’ve missed out on a key warning to prepare for this exact scenario.  Promises of 500,000 tests a day in October do us no use now when we know that these estimates aren’t reliable.”


Prof James Naismith FRS FRSE FMedSci, Director of the Rosalind Franklin Institute, and University of Oxford, said:

“It seems clear that the logistics of the testing system are under severe strain.  I can think of no other reason why the claimed capacity is so far ahead of the number of tests processed.

“Science can test hundreds of thousands samples a day, new technology might indeed push us towards a million.  Without good logistics to take samples where they are needed and deliver in the appropriate form to the testing site, it won’t matter.

“The bouncing around of positive daily tests suggests that something is awry in data reporting.

“It would seem desirable that government focus on the rather dull but crucial work of managing the logistics.  The high profile shortcomings will undermine public confidence in the system, at precisely the time it is needed most.

“What does this mean?

“1. The testing system has not collapsed.

“2. We are able to monitor the spread of virus.  The number of positives as proportion of tests remains low.

“3.  On their own, issues with the testing system do not curtail our ability to contain viral spread.  The failure to effectively isolate infectious people dwarves all other problems.

“4. The rise in cases is concerning given the winter is coming, but we are far from the dark days of March.  We still have time but none to waste.

“5. Cases in the young present little health risk since the disease is mild for all but a few where it can have tragic consequences, but in every country where cases rise sharply, hospitalisation and deaths have followed.  It is magical thinking to believe the UK will be different.

“6. Medical and scientific advances mean that the death toll will be now be much lower from serious infections.

“I and many other scientists urged a serious attempt be made in May to build a test, track and isolate system.  We all stated that it would be extremely hard work to do this and it needed sustained focus.  I stressed that all three legs are needed, two on their own are useless and largely a waste of money.  These are not problems of science, they are problems of organisation, direction and management.

“What is needed in my view, is a tracing system that reaches the contacts of a person with a positive test within a day and asks them to isolate immediately.  Within two days all these contacts should be tested and those who are positive are financially and otherwise supported to continue to isolate whilst those who are negative are immediately allowed to return to life.  There is no perfect system, there is a risk of false negatives of course but the most infectious people are usually the easiest to identify by testing.

“However, the rise in cases we have seen and the imposition of a rule of six, is precisely what an effective test, trace and isolate system with public health measures (hand washing, masking, some social distancing and improved ventilation indoors) should have avoided.

“Without public confidence and effective isolation, even a million tests a day will not solve our problem.”


Prof Brendan Wren, Professor of Microbial Pathogenesis, London School of Hygiene & Tropical Medicine, said:

“It seems that there are several bottlenecks in the testing procedures.  These are not being made publicly available so we can only speculate that these may be limited materials for the testing process, capacity and procedural issues.  This needs to be addressed urgently and if it is capacity then university labs should be more widely employed”


All our previous output on this subject can be seen at this weblink:


Declared interests

Dr Stephen Griffin: “No conflicts.”

Prof Brendan Wren: “No conflicts.”

None others received.