I’m a geriatrician and recently, while visiting an aged care facility, I had a conversation that left me floored.

One of the nurses was talking about how incredibly amazing the local hospital network was because they provided them some PPE.

This nurse works at a large aged-care facility in Melbourne. She is intelligent, dedicated and hard-working. The facility she works at is owned by a publicly listed company which made huge profits last year, yet she only got PPE when it was donated by a public hospital!

Generally, people don’t move to residential care because they are enjoying excellent health. People go to residential care because they need help with activities of daily living, whether due to frailty, other medical conditions or dementia.

Every year, I see outbreaks of flu or gastro, but with COVID-19 the vulnerability of residents to infection has become more stark than ever.

In Australia, we have only had one residential care facility with sustained transmission, Newmarch House in Sydney, which lead to 19 deaths. According to data from the Kaiser Family Foundation, 46 per cent of all US deaths from COVID-19 occurred in residents of residential aged care.

Part of the vulnerability to COVID-19 comes from age-related changes to immune function.

With age comes a decrease in the ability to create antibodies, which are specific immune proteins that can target a particular microbe. This means it is harder for older adults to control viral infections because their immune systems don’t have the same capability to produce antibodies.

People who are older have faced far more infections than someone who is young, so with age we have less of a cell type called “naïve T-cells”, which are able to stimulate an antibody response to a new threat. This means that one of the key reasons older adults are more susceptible to COVID-19 is that they just aren’t able to produce an effective antibody to combat and control the disease.

Older adults, particularly those who are frail, also have higher baseline levels of inflammation, due to an age-related accumulation DNA and tissue damage, as well as “senescent” cells which are damaged and can no longer replicate, but still produce chemical messengers to turn on inflammation. Most people die from COVID-19 because of high levels of inflammation in the lungs, with fluid and white blood cells moving into the air space and making it impossible for oxygen to get into the bloodstream.

It is the combination of an ineffective antibody response to control the infection, and a non-specific immune response so dramatic it actually damages tissue.

The risk from COVID-19 isn’t just due to physical factors. Time and time again we have seen that outbreaks of COVID-19 occur in groups of people who are not able to isolate.

Residential care is a perfect tinder box of vulnerable people, kept inside together, dependent on the same over-worked staff for help with their basic needs.

I can’t comment directly on the outbreak in Newmarch house, but I have spoken to so many staff in residential care facilities who are terrified for their residents. Residential care facilities are peoples’ homes, they share spaces like dining and lounge rooms. If one person gets sick, it’s highly likely they’ve already come into contact with many others.

Not only do staff have inadequate PPE, there are no minimum staff ratios. Since most facilities are run for profit, keeping staff numbers low saves money, which means these staff work incredibly hard, even without needing to practice heightened infection-control procedures.

This is why many residential care facilities felt forced to go into lockdown, to prevent families visiting their loved ones, knowing the distress it would cause, but also knowing that one mistake could portend tragedy.

This has led to a second epidemic, this one of loneliness, where people have suffered mental anguish by being cut off from their families.

The aged-care sector relies on public funds to make money for shareholders providing care to some of the most vulnerable people in our society. Since publicly listed companies are obliged to make profits, there is a direct conflict of interest to spending money to provide the best care possible. One of the first steps in giving back older adults their human dignity would be simple regulation about resident-to-staff ratios.

One lesson we can take away from this pandemic is that disease is not a great equaliser. We don’t all have the same risk of dying, and we don’t have the same risk of getting the disease in the first place.

The death toll in residential care have been staggering, a sign we need to step back as a society and think about how we can do better at caring for those who need our help.

Staying Alive by Dr Kate Gregorevic is out now from Pan Macmillan.