Can Covid-19 Spread Via Building Pipes?

As I explained a couple of weeks ago, it seems plausible that the 2019 Coronavirus (now officially designated as Covid-19) may spread e.g. vertically through a building of flats via the various piping systems. This is based on a theory of what happened in a cluster of SARS cases in Hong Kong in 2003.

CNN and others are discussing this today after officials in Hong Kong partially evacuated a building where this is again a possibility.

The Role of Sanitation in Slowing the 2019-nCov Coronavirus

While most media reports have been focusing on the respiratory side and pneumonia-like symptoms — the fevers, and coughs, and protective measures like face-masks, it may be that toilets, latrines, and sanitation are an important part of the story of the 2019-nCov outbreak.

This paper by Chan et. al examines a familial cluster in Shenzhen, and monitored gastrointestinal (GI) symptoms as well as respiratory ones. As they point out:

“Diarrhoea and gastrointestinal involvement are well known in coronavirus
infections of animals and humans.”

Indeed, as summarised in a recent story from Bloomberg:

A virus-laden aerosol plume emanating from a SARS patient with diarrhea was implicated in possibly hundreds of cases at Hong Kong’s Amoy Gardens housing complex in 2003. That led the city’s researchers to understand the importance of the virus’s spread through the gastrointestinal tract, and to recognize both the limitation of face masks and importance of cleanliness and hygiene, [John Nicholls, a clinical professor of pathology at the University of Hong Kong,] said in an interview. […]

Many of the emerging coronaviruses are so-called pneumoenteric viruses, meaning they can replicate both in the respiratory tract and the gastrointestinal system, said Ralph Baric, professor of microbiology and immunology at the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill, who has studied coronaviruses for decades. Overwhelmed by hundreds of severely sick pneumonia patients, doctors in Wuhan might not have focused on any gastric signs, Baric said in a phone interview.

The Bloomberg story also links to this paper from Li et al. on early transmission dynamics of the virus

“Confirmed cases could more easily be identified after the PCR diagnostic reagents were made available to Wuhan on January 11, which helped us shorten the time for case confirmation. Furthermore, the initial focus of case detection was on patients with pneumonia, but we now understand that some patients can present with gastrointestinal symptoms, and an asymptomatic infection in a child has also been reported. Early infections with atypical presentations may have been missed, and it is likely that infections of mild clinical severity have been under-ascertained among the confirmed cases. We did not have detailed information on disease severity for inclusion in this analysis.” (emphasis added)

If a GI-associated route is part of the story and the sanitation arrangements (pit latrines, squat latrines, toilets, covers, hand washing with soap and water, etc.) are very different between locations then this may well play a part in the story as it continues to develop.

The Personal and Systemic Costs of Hidden Flood Risk

Following the recent floods in Ottawa, the CBC’s Neil MacDonald has put together an interesting piece:

I would never consider buying near the river nowadays, for obvious reasons, and my guess is the miserable residents on those sandbagged streets spend a lot of time contemplating both their home values and the next catastrophic flood. There have been two in the last three years. The Ottawa River surged past its banks weeks ago, and is still frighteningly swollen.

It never occurred to me, back in 2015, to check whether the home we tried to buy was at risk of flooding. Being near the river was a plus, not a threat. And even if I had checked, it probably wouldn’t have done much good. Flood plain maps in Canada are about 25 years out of date.

But that’s about to change. Next year, the federal government will begin uploading nearly 2,000 user-friendly flood plain maps, updating them with the most recent geospatial data. Eventually, entire communities will find themselves publicly identified as at-risk. What that will do to the value of their homes and their flood insurance premiums (assuming they can even get insurance), is obvious.

The article also features some discussion and estimates from Prof. Feltmate of the Intact [Insurance] Centre on Climate Adaptation.

Teaching the Future to Drive Change Today

A study published in Nature Climate Change last week asks whether teaching middle-school children can be done in a way that promotes engagement (and drives the views) of their parents:

“Because climate change perceptions in children seem less susceptible to the influence of worldview or political context, it may be possible for them to inspire adults towards higher levels of climate concern, and in turn, collective action. Child-to-parent intergenerational learning—that is, the transfer of knowledge, attitudes or behaviours from children to parents—may be a promising pathway to overcoming socio-ideological barriers to climate concern.”

The study was performed on families with middle-school students in North Carolina, and involved four lessons and a project, as summarised here:

“The first lesson taught the difference between weather and climate. The next was on how the environment relates to animals and where they live. The third looked at how people who work with wildlife can help the animals adapt to climate change, if they can do so. The fourth lesson focused on how an individual can directly affect the environment.[…] The students also did a climate change-focused service learning project, created a blog post about what they were learning and interviewed their parents about the topic.”

The results presented in the abstract suggest the strategy is effective at influencing:

“Parents of children in the treatment group expressed higher levels of climate change concern than parents in the control group. The effects were strongest among male parents and conservative parents, who, consistent with previous research, displayed the lowest levels of climate concern before the intervention. Daughters appeared to be especially effective in influencing parents. Our results suggest that intergenerational learning may overcome barriers to building climate concern.”

It should also be pointed out that promoting parental engagement is, in the modern era, a worthwhile outcome in and of itself.

But I think it is also reasonable and important to acknowledge that promoting some of these strategies is not without risk. We have learned that there’s no shortage of people, with all sorts of agendas, trying to hack social systems and institutions to exert influence today.

While better tools for broader education are desirable (and badly needed), too often these have also been to obfuscate and indoctrinate. So critical thinking skills, a credible evidence basis and opportunities for robust two-way discussions (i.e. embracing [real] debate, and bringing counterpoints back to the classroom) are all going to be keys to doing this in a responsible way.