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We’ve explored the progress made toward a vaccine and dived into the evolving and largely positive immunity picture, but there’s even more good news out there in our fight against the coronavirus. Here is a grab bag of research that shows we’re making progress in this pandemic.

Take your vitamins

You can get vitamin D in three ways:

1. Your skin produces it when exposed to sunlight.

2. You get it when eating a diet of foods that naturally contain it, like fish or egg yolks, or that have been fortified with it, like milk.

3. You take a supplement, like a multivitamin.

It turns out that vitamin D seems to be pretty good for your immune system in addition to your bones. In fact, a 2017 study found that vitamin D played some role in helping to prevent acute respiratory infections.

Given this, we’ve naturally been looking at it in regard to COVID-19; in general, there’s been a lot of studies from an associative point of view. For example, countries with higher rates of vitamin D have had lower rates of coronavirus infection. One Italian study found that people who reported taking vitamin D supplements were less likely to be infected; another Italian study found lower levels of vitamin D in COVID-19 patients than they’d expect to find in the population. A U.S. study found that lower vitamin D levels were associated with increased COVID-19 risk. There also have been a couple of studies that have failed to find a link.

What we don’t have is a randomized, controlled trial (RCT) in which we give some people vitamin D, and some people a placebo, and see if there’s any difference in COVID-19 infections. When we’ve run huge RCTs on vitamin D supplements with cancer and cardiovascular diseases, we’ve found nothing. And honestly, it’s not hard to think of reasons why people with low vitamin D would be more likely to have COVID-19: People who are low on vitamin D might spend more time indoors, where they’re more likely to be infected. Sick people stay inside. And sunlight itself may have therapeutic qualities in general.

I’ve typically avoided writing about treatments without RCTs to back them up, but I’m making an exception because vitamin D is super safe. Unless you take huge quantities of it, you’re going to be just fine. In general, getting out in the sun for just a few minutes a day is really helpful, and a vitamin supplement may help too. This is a very-low-risk, potentially-medium-reward thing you can do.

Smoking isn’t a big risk factor

Smoking is terrible for you. You shouldn’t do it. I just want to make that clear.

And yet, smoking doesn’t appear to make the virus worse.

Here’s the research. One study found that countries with higher rates of smoking actually had fewer coronavirus deaths. One comprehensive look at 18 peer-reviewed studies and 12 pre-print studies found that, when you adjusted for age and gender, smoking prevalence among hospitalized patients was about one-third of what you’d expect if smoking had no impact.

What about nonhospitalized patients, people who just test positive? Looks like we get similar results. In Israel, they looked at their 114,000 tests and found that 9.8% of those with the disease were smokers, compared to 19.4% of the negative tests.

Heck, we can even do this analysis in Utah. In 2018, 9.2% of Utah’s population smoked. But only 5.1% of Utah coronavirus cases have been current smokers, and only 4.7% of our hospitalized cases. Some of that discrepancy is due to lower smoking rates in the aging population, but that doesn’t explain all of it.

What’s going on here? There are a whole bunch of hypotheses. One that would explain it most easily is that people who smoke are used to having respiratory symptoms like coughing and trouble breathing, so they don’t go in to get tested for the virus. (There are arguments against this, such as that serological surveys also seem to show the same smoking split.) Another is that people with preexisting conditions that make COVID-19 worse may be more likely to quit smoking. Yet another is that smokers choose to socialize outside more due to their smoking.

But there are some explanations that might explain it from a biological perspective. One is that nicotine inhibits the production of inflammatory cytokines, the body’s proteins that we see elevated levels of during the “cytokine storm” late stages of the disease, where essentially your immune system is attacking the body.

It’s also possible that having your lungs coated with a thin layer of tar and toxins is normally awful but in this case has the side effect of preventing coronaviruses from being able to infect lung cells. (Generally, smokers have a higher risk of flu, but there is at least one team of scientists who think the shape of the coronavirus and how it attaches to cells might make this different.)

Look, smoking is more likely to kill you than the coronavirus is, so don’t start smoking on the back of this research. I’m sure that there’s some sort of bad-journalism Razzie award for those who advocate that their readers smoke, and I don’t want to win it. But if you are a smoker, hopefully this reduces your stress somewhat.

Advances in treatments

We’re clearly getting more and more tools to treat the coronavirus effectively.

Remember what a big deal it was when we gave a Utahn blood plasma transfusions from someone who had already recovered from the disease back in April? In that case, loss of life looked so likely that they were willing to experiment. The patient got better.

We’ve now done over 20,000 of these plasma treatments in the United States, and we know they’re quite safe. Serious adverse effects were found in fewer than 1% of patients. Mortality for patients declined from 12% to 8.6%. The Mayo Clinic also notes that “now there is sufficient donation to meet most of the demand.”

You may also remember the dexamethasone finding, that this steroid given orally in late-stage COVID-19 patients really had an impact on mortality. One recent study of another steroid, methylprednisolone, found that prolonged, low-dose treatment “was associated with a significantly lower hazard of death” — 71% lower, in fact. That’s really good!

Again, these aren’t drugs you should be taking at home, because the steroids will hurt your immune system. But for those who are in COVID-19-induced cytokine storm, it seems like a good bet. It’s also good news for the cost of treatment: Methylprednisolone costs about $10, and is widely available.

Reduction in mortality

As a result of these treatments, it’s becoming more clear that fewer sick people are dying.

The best data comes from England, where we’re seeing death rates go down significantly among people who are hospitalized with the disease.

The death rate among hospitalized patients in England is decreasing. (https://www.cebm.net/covid-19/declining-death-rate-from-covid-19-in-hospitals-in-england/)

In all, the rate in England has gone from about 6% of hospitalized cases dying at the beginning of April to about 1.5% at the end of June. That’s a big difference!

Improvements in treatment is just one reason for the four-fold difference, and probably doesn’t explain all of it. Other possible explanations: that the most vulnerable were more likely to die first; people may be more likely to enter the hospital with COVID-19 symptoms than they were in the past; and people who caught the coronavirus earlier when no precautions were being taken may have gotten a larger dose and therefore a more potent case of the disease.

In Utah, the data needed for this calculation isn’t public: We don’t know exactly when deaths occurred or when they were first hospitalized. Over the entirety of the pandemic, there have been 2,109 hospitalizations due to COVID-19, and 251 have died. That’s 12%, though that also counts the deaths of people who never made it to the hospital for one reason or another. The difference between Utah’s and England’s numbers may reflect fewer people going to the hospital in Utah than in England, a lower standard of care, or a difference in measurement. We just don’t know.

The U.S. picture shows that deaths are certainly up as a result of our recent coronavirus spike, but perhaps less than anticipated so far. I expect that death trend to follow the case trend overall, but a more muted wave of deaths wouldn’t be just good news, it would be great news.