A Time to Re-Examine Bubbles

A Covid Party

Nine people have contracted covid after gathering in each other's homes at a number of different events - including one attended by someone who allegedly broke their isolation after arriving from a 'red zone'. Covid was the unexpected guest at the party.

The timeline was given by Bailiwick Express:

Saturday 6 February
In the afternoon, A visits B and C at B's house for four hours.
D and E join them. D arrived back in Jersey three days ago.
That evening, A and B attend a party hosted by F. F and three other guests later test positive for covid.
Thursday 11 February
A person in F's household (G) has a friend to visit (H).


Sunday 14 February
Someone in H's household (I) starts showing symptoms and calls the helpline for a test.
H attends a party hosted by J with 10 people in attendance.


Tuesday 16 February
H and I test positive.
Contact tracing begins with the guests from J's party.


Wednesday 17 February
K, who has been in contact with F, is contact traced and tests positive.
A fourth guest from the original party on 6 February tests positive.

Restaurants, 2 metres, and airflow

So what if the party had been held at a restaurant? No one was showing symptoms for much of the time when H attends a party.

Part of the problem with the two metre rule is that it doesn't work in real life. A recent BMJ study showed that "Rigid safe distancing rules are an oversimplification based on outdated science and experiences of past viruses". They noted that:

"Droplets exist across a continuum of sizes. Contextual factors such as exhaled air and ambient airflow are extremely important in determining how far droplets of all sizes travel. Without exhaled airflow, the largest droplets would travel furthest (1-2 m), while the small ones would encounter high resistance (drag) and stay close to the source. When accounting for the exhaled airflow, clouds of small droplets can travel beyond 2 m in the air, and even large droplets have enhanced range."

And they point out that airflow within a confined space - such as a restuarant - can aid transmission:

"Specific airflow patterns, and not just average ventilation and air changes, within buildings are also important in determining risk of exposure and transmission. A case report from an outbreak at a restaurant in China described 10 people within three families infected over one hour, at distances of up to 4.6 m and without direct physical contact. The pattern of transmission was consistent with the transient indoor localised ventilation airflow pattern. Few studies have examined how airflow patterns influence viral transmission; most studies report (if anything) only average indoor ventilation rates. Neglecting variation in localised air flow within a space oversimplifies and underestimates risk modelling."

If anything, this was one of the major contributory factors to the outbreak at the Royal Yacht Hotel, where the hotel was unfairly criticised by social media for breaking the rules - they broke other rules, but that's a different matter.

Studies show that airflow is not consistent - so think of heating in winter, which causes convection currents to permeate a restaurant. There are not usually many "cold spots" which means that hot air - and any small droplets they carry - can go far beyond the two metre distance.

So what can we say: the two metre distance is good as a precautionary measure, and it can slow the spread of the virus, but the notion propagated by the government that it is a safe, controlled space, is a pure chimera.

Bubbles - the Safe Way to Re-Open

Putting all mixing of households into one basket is a major mistake. Back in June, one of many studies on the idea of social bubbles.

The best way to reduce the spread of the coronavirus post-lockdown is for people to limit their interactions to a few repeated contacts, or so-called social bubbles, research from the University of Oxford showed.

Social bubbles vary, but the basic idea is to have a limited number of interactions.

For example, in Canada:

No one is permitted to gather socially with anyone outside of their immediate household or “core bubble”. A “core bubble” can include a maximum of two relatives, friends, partners, or co-parents who happen to live in a different household.

The authors of the Oxford study comment that:

“Strategic reduction of contact can strongly increase the efficiency of social distancing measures, introducing the possibility of allowing some social contact while keeping risks low. This approach provides nuanced insights to policymakers for effective social distancing, which can mitigate negative consequences of social isolation.”

Support Bubbles

This is the approach taken successfully in neighbouring Guernsey, both as they came out of the March lockdown, and now again. First of all, they saw the obvious need for support bubbles:

Support bubbles can only be formed under a specific criteria is as follows:

Where there is only one adult (this includes households with one adult living alone or one adult and any children under the age of 18);

Where there is only one adult carer (this means households where this is one adult carer and anyone else living within the household has a disability and requires continuous care);
Where there is a child under one, regardless of how many other adults are in the household;
Where there is a child under 5 with a disability that requires continuous care (regardless of how many other adults are in the household); or
Where an individual needs to move to another household to support their physical and mental wellbeing.

Widening Bubbles

This happens as numbers decline:

"From today, all households will once again be able to 'bubble' together. That means households can socialise with members of one other home and Islanders do not have to observe social distancing advice with members of their chosen paired household. The rules are restricted to entire households, meaning people do not get to expand their bubble individually."

And this has been improved this year:

"A slight change this year will be that five people from separate households will be able to meet outside, as long as they socially distance. It’s hoped that this will allow people who might miss out on a bubble the opportunity to still socialise."

As last time, this allows flexibility. Back in 2020, it expanded to a different stage, so that the household bubble of two household could 'double up' so your bubble now contains four households. This could be four single bubbles now joining together, two double bubbles or an initial joined bubble with two other single bubbles.

"By Phase 3 we were able to spend time with up to four households, with a subsequent move away from household bubbles in Phase 4 and we then reached a Bailiwick-wide bubble in Phase 5. "

Rather than just coming out with the ridiculous mantra that household mixing is not allowed because it cannot be controlled, our Government needs to take a close look at our neighbour and elsewhere where gradual expansion of "bubbles" makes a way to both have household mixing, and control contacts, in a much safer way than restaurants.

For more on Bubbles, see my earlier:
http://tonymusings.blogspot.com/2020/05/why-jersey-needs-social-bubbles-urgently.html