Why is the growth of cases of Covid-19 growing, but the death rate is falling?

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

In situations with coronavirus in Russia and in the United States, there is a lot in common: now cafes and shops are opening, masking is being canceled. But is everything as optimistic as it seems at first glance? We've translated an article by journalist Dylan Scott on why the updated data might mislead us and why it's too early to forget about the dangers of Covid-19.

In the new outbreaks of coronavirus in the United States, much remains in question: the incidence is growing, but the country has the lowest death rate since the start of the pandemic. You don't need to be a specialist to notice the discrepancy in the numbers: 56,567 new cases of Covid-19 were detected in the United States on July 3, a record high. On the same day, 589 new deaths were recorded, which, in turn, indicates a prolonged and gradual decrease in mortality. There have not been such low figures since the end of March.

When people observe these conflicting trends, the question arises: if the number of deaths does not increase with the cases of the disease, then why not move on to the next stage of exiting quarantine measures? In the end, the numerous blockages of the self-isolation regime have brought huge losses both in monetary terms and in terms of people's mental health. If the mortality rate is no longer the same as in April and May, then there is nothing to prevent the economy from working at full capacity.

Experts say it's too early to rejoice: an increase in the number of infected may be a harbinger of a large number of deaths in the future. And even if mortality data do not rise to the levels seen in April and May, people are still vulnerable.

The new coronavirus, SARS-Cov-2, is an incredibly slow-acting pathogen. Experts say the declining death rates reflect the state of the pandemic a month ago or more, when the original hotspots were localized and only a few states began opening restaurants and businesses.

This means that it may take several more weeks before we see the consequences of new outbreaks of infection. In the meantime, the virus will continue to spread. When the numbers show that the crisis has already arrived, it will be too late. Difficulties only await us.

Even if mortality remains low in the near future, it should not be argued that there are no more risks. Over the past few weeks, thousands of Americans have been hospitalized for lung problems. Young people, who account for the majority of recent infections, have a low risk of dying from the virus, but the likelihood remains.

In addition, some of the sick still need hospitalization. Early research suggests that people who are infected with the coronavirus and survived the disease suffer relatively easily from damaged lungs and other complications that can lead to future health problems.

“An increase in the number of people infected means a faster spread of the virus in society,” said Kumi Smith, who studies infectious diseases at the University of Minnesota. "And the faster this virus spreads, the more likely it is that it will eventually infect someone who could die or suffer serious consequences."

Unfortunately, Smith points out, it’s worth refraining from doing things you enjoy right now in order to help other people.

There is another, perhaps more serious problem - the government's reluctance to take the steps necessary to combat the disease. A few months ago, experts warned that if the United States relaxed its social distancing policy too quickly, turning a blind eye to the need for additional testing or contact tracing, new coronavirus outbreaks would flare up and become more difficult to contain.

Why, along with the number of cases, mortality does not grow

The contradiction between the two curves - the number of cases, which creeps up, and the number of deaths, tending downward - is the main reason why some people want to speed up the process of lifting restrictions, thereby exposing themselves to new outbreaks of coronavirus disease. It is important that such a difference is actually to be expected. Experts say there is a large lag - up to six weeks - between when a person becomes infected and when their death is reported in the official tally.

“Why is mortality not growing along with the number of cases? Thinking in this way is wrong, says Eleanor Murray, an epidemiologist at Boston University. - In the latest data on infected, those who probably caught the infection a week or two weeks ago are marked. The mortality data reports the deaths who were infected about a month ago - in their cases, the infection could develop up to six weeks or more."

“Some people get infected and die quickly, but most die after a while,” Murray continues. “It's not about the one week delay between incidents and deaths. We expect something more, on the order of four, five or six weeks behind."

According to the Covid Tracking Project last week, the recent spike in the number of cases began around June 18 and 19. It was not that long ago, so you shouldn't expect the current mortality data to refer to these numbers.

“Hospital admissions and deaths are lagging because it takes time for the disease to progress,” says Caitlin Rivers of the Johns Hopkins Center for Health Security. "The recent spike started about two weeks ago, so it is not yet known whether we will see an increase in hospitalizations and deaths or not."

Overall numbers can also obscure local trends in the fight against the virus. According to the Covid Tracking project, hospital admissions are increasing in the south and west, but at the same time they are dropping sharply in the northeast, the initial epicenter of the outbreak in the United States. A similar regional shift could occur with mortality data, although it will take time to identify this. But even now, Alabama, Arizona, Florida, Nevada, South Carolina, Tennessee, Texas and Virginia are seeing a rise in average daily mortality, according to the Covid-19 exit strategy, while Connecticut, Massachusetts and New York are seeing marked declines. …

On the one hand, doctors have identified therapies, such as remdesivir and dexamethasone, that shorten the time people spend in hospital and improve the survival rates of patients with COVID-19 on ventilators. On the other hand, new infections are more detected in young people - they have a much lower risk of dying from coronavirus than in older people.

Young people are less susceptible to Covid-19, but the risk of getting sick is not zero

About 3,000 people under the age of 45 have died from the coronavirus, according to CDC statistics. This is a small percentage compared to the total number of deaths from Covid-19 in the United States, but it is there. In addition, young people can develop serious complications that can ultimately lead to hospitalization. Again, their risk is significantly lower than that of older people, but that doesn't mean it's zero.

A recent study published in the journal Nature showed that even in asymptomatic patients with Covid-19, changes were found in the lungs. It is also known that some people who get sick continue to report health problems during the weeks following recovery due to complications from the infection. These include scarring of the lungs, thrombosis and stroke, heart damage, and cognitive impairment. Thus, if a person has had Covid-19 with relatively mild symptoms, they cannot simply return to normal life.

But even admitting that young people face less of a threat from the coronavirus, there remains another major cause for concern if the virus continues to spread in this population: it can very easily move from less vulnerable people to those at higher risk of getting serious complications.

Coronavirus can easily move from young people to more vulnerable age groups

One of the answers to the listed set of facts may be as follows: "We must isolate the old and the sick, while the rest will live in peace." This is good in theory (especially if you are not of the older generation and do not suffer from weakened immunity), but in practice, everything is much more complicated.

“The point is that we live in communities that are closely intertwined with each other. That's a problem, says Natalie Dean, professor of biostatistics at the University of Florida. "And it's not that there are clear lines within communities: you have a high risk of getting sick, you have a low risk."

Florida data show that in late May and early June, young people under 45 were more likely to become infected. But after about a week, new cases began to come to light among the population over this age. Nursing homes in Arizona and Texas - two of the most alarming trends right now - have seen outbreaks in recent weeks as the number of cases rises. After all, people who work in nursing homes live in a society where Covid-19 is spreading. And because they are younger, they may not show symptoms while they go to work and potentially expose older patients to infection.

In both Massachusetts and Norway, one expert noted, about 60 percent of deaths occur in long-term care facilities. It can be assumed that society has yet to find a good strategy to protect certain groups of the population.

“We don't have much evidence on how to protect the most vulnerable social groups when transmission is widespread in the population,” says Mark Lipsich, an epidemiologist at Harvard. “This means that the best way out is to try to contain the spread of the disease, as this will reduce overall morbidity and mortality (as in Norway) and prevent overloading the health system.”

We don't need to lock ourselves in forever - but we need to be reasonable and vigilant

Blocks are extremely cumbersome. Tens of millions of Americans have lost their jobs, drug overdoses have increased, and deaths from heart disease have increased. This suggests that people who previously sought medical help stopped doing so during the outbreak of coronavirus infection.

But without blocking, we cannot destroy the virus. Experts warned that if businesses in the States resume operations too early, the number of infections would skyrocket. This will put a strain on the health care system and increase the risk of more deaths.

If the summer heat somewhat suppresses the virus, then a second wave may occur in the fall and winter. That is why we must find a balance between the needs of the people and the reality that most of us are still exposed to an entirely new pathogen that is more deadly and more infectious than the flu.

“I see that the opening of the establishments is interpreted by many as a return to the 'pre-coronavirus era', when we attended group events, regularly talked with different people and got together without masks, - said Kumi Smith from Minnesota. "But the virus hasn't changed since March, so there is no reason to forget the precautions."

To date, most States have reopened bars but closed schools. However, one of the most thorough studies on the impact of bans on the spread of Covid-19 found that closing restaurants and bars had a significant impact on the virus, while school closings did not. Masks are also not a panacea, but they help reduce the spread of coronavirus.

Experts agree that Covid-19 still poses a risk for Americans, and it goes beyond the boundaries of normal life. We know what needs to be done at home to slow the spread of the coronavirus. But we need our governments, from Washington to capitals of different States, to become smarter when it comes to starting businesses.

Only collective action will help get rid of the coronavirus forever. Other countries understand this too. We must take action now, before it is too late.