Oxford model: Half of the British population may already be affected by coronavirus

(Patria) - Given the differences in testing regimes worldwide, the true rates of mortality and hospitalization due to coronavirus are not easy to confirm, writes the New York magazine Intelligencer.

However, modeling carried out by researchers at the University of Oxford could result in good news, even if it doesn't sound so good at first.

Namely, according to hypothetical modeling by the Oxford Laboratory for the Ecology of Infectious Diseases, half of the UK population may have already been infected with the coronavirus.

If accompanying studies confirm this modeling, it will show that only a minor portion of those infected required hospitalization, while the vast majority had only mild symptoms, if any at all.

The Intelligencer further writes that in a mathematical experiment, researchers observed a population at risk for severe infection. While a risk rate of 0.1% suggests a high number of infections – implying lower hospitalization and mortality rates – a rate higher than 1% implies the possibility that the virus could prove to be a greater threat to the entire population.

In the first scenario where the rate is 0.1%, the coronavirus arrived no later than mid-January and spread for a full month, still undetected, before the first cases were confirmed.

Based on the epidemiological SIR model (susceptible-infected-recovered), commonly used in epidemiology, with data from reports on the number of cases and deaths in the UK and Italy, researchers have determined that the British government's initial strategy of achieving 'herd immunity' could be justified.

The head of the research team, Sunetra Gupta, claims to be 'surprised by the unqualified acceptance of the Imperial model,' referring to an academic report predicting 250,000 deaths in the UK if the government implements a plan to suppress the virus but 'does not suppress it completely.' 

Earlier this week, there were 8,077 infected people in Britain (out of 90,436 tested), with 87 deaths.

Verifying this estimate, the Oxford team is now working with teams from the universities of Cambridge and Kent to begin antibody testing to determine the current stage of the epidemic, Gupta told the Financial Times.

The general medical significance of antibody testing is also emphasized by Laurie Garrett, a Pulitzer Prize winner who reports on infectious diseases:

- Most importantly, the test serves as a public health tool. If we had an antibody test, we could test the population of New York and determine how many had or currently have the virus in their bodies. Since we know this virus has never been in the human body before, anyone with antibodies against the virus would have, by definition, been exposed since January.

If we could produce an antibody test in mass quantities – and I know that's what's being worked on – and put it into commercial use, it could change the entire perspective on the pandemic, Garrett explains, adding:

- What would be good to know now is how many people who had pneumonia since January actually had coronavirus? The answer to that question would make a difference at the political level. If we suddenly noticed an increase in cases of hidden pneumonia since mid-February, it would show us that we are in big trouble; that it's like Italy here; that we will face an astronomical surge in infections and our hospitals will be full. Conversely, if the same number of cases were found in samples from January 1st, it would show us that, okay, it's developing gradually but we don't have to lock down every person in New York, maybe we can flatten the curve, which makes a huge difference in our approach, which wouldn't have to be so drastic, Garrett emphasizes. 

Although the Oxford model sounds promising, like all other studies investigating the coronavirus, it should be approached with caution. Namely, if antibody testing does not confirm the epidemiologists' findings, the modeling could significantly jeopardize the social distancing measures that public health experts consider vital for stopping the spread of the coronavirus.

If nothing else, this initiative underscores the need for an adequate level of testing so that governments can make decisions that correspond to real infection and hospitalization rates, writes Intelligencer.