Bad news from Corona for those who are overweight

In the details, Doctor Jesus Eugenio Sosa Garcia, who is responsible for critical cases in the intensive care unit at Medica Sur Hospital in Mexico City, confirmed that the most prominent factor among all the high-risk cases with Covid-19 disease that he treated was obesity.

He added, according to the medical journal Nature, that he and his colleagues examined statistics early in the epidemic and found that half of the 32 patients admitted to the intensive care unit were obese.

Despite optimism that a vaccine against the emerging virus will be produced soon, but for Mexico and many other countries with an increasing number of people with high body mass indexes (BMIs), some researchers fear that the vaccine may not be the panacea that doctors and patients hope. Both

An unexpected new source of corona transmission

Clinical trials

In the United States, “We're concerned about that,” says Donna Ryan, who studies obesity at the Pennington Biomedical Research Center in Baton Rouge, Louisiana. Vaccines, which are helpful for a handful of other conditions, often don't work well for severely obese patients. This suggests that the COVID-19 vaccine may not provide as much protection as hoped for.

Although the researchers were unable to be sure whether obesity would affect the efficacy of the vaccine, it is likely that alternative ways will be found to counteract the problems if they arise. But the scientists also expressed concern that clinical trials may not be able to detect such problems immediately or in the early stages.

The risks are constantly increasing

Also in China, it became clear early in the outbreak of the Covid-19 disease that obesity increases the risk of infection, when epidemiologist Lin Shu at Sun Yat-Sen University in Guangzhou was analyzing the data of the first wave of the epidemic in the country, she noticed the emergence of a pattern in a model One by one, he suggests that BMI has always been a clear factor in the severity of COVID-19 cases.

Possible reasons

When she submitted her study to an academic journal in March 2020, the editors in charge of issuing the journal urged her to communicate with WHO officials and alert them about her findings.

Since then, the results of scientific studies around the world have emerged, which have reached the same conclusion, that those who are obese are more likely to die when they have Covid-19 disease compared to those who are of normal weight, even in the presence of factors such as diabetes. And taking high blood pressure into account.

adipose tissue

In addition, obesity can exacerbate the metabolic effects of coronavirus infection. Adipose tissue expresses relatively high levels of ACE2 (angiotensin-converting enzyme 2) that the coronavirus uses to invade cells. “Adipose tissue seems to act as a reservoir for the [novel coronavirus],” says Dr. Gianluca Iacobilis, an endocrinologist at the University of Miami in Florida.

chronic inflammation

But it's the effects on the immune system that are most worrying for some researchers, because obesity can cause chronic low-grade inflammation, which is thought to contribute to an increased risk of conditions such as diabetes and heart disease. As a result, the researchers suggest, obese people may have higher levels of a variety of immune-regulating proteins, including cytokines.

Immune responses released by cytokines can damage healthy tissue in some severe cases of COVID-19, said Milena Sokolowska, who studies immunology and respiratory diseases at the University of Zurich in Switzerland. Paradoxically, Dr. Sokolowska explains, a persistent state of immune stimulation, or persistent exhaustion, may impair some immune responses, including a T-cell response that can directly kill infected cells.

longer period of time

Initial evidence suggests that SARS-CoV-2 infection persists for five days longer in obese patients than in those who are thin, said Daniel Drucker, an endocrinologist and physician at Mount Sinai Hospital in Toronto in Canada.

gut and lung microorganisms

While Sokolowska added that obesity also leads to lower and less diverse groups of microbes in the gut, nose and lung, as well as problems with metabolic functions compared to lean individuals. She explains that gut microbes can affect the reaction of the immune system to resist pathogens or the body's use of vaccines, citing in this context what researchers announced, last year, for example, that changes in the gut microbiome due to taking antibiotics negatively affect the immune system. The body's response to the influenza vaccine.

13% of adults in the world

According to the latest data from the World Health Organization, about 13% of adults in the world are obese. Professor Ryan points to studies of vaccines against influenza, hepatitis B and rabies, which have shown lower responses in those who are obese than those who are lean. Professor Shaw says: "In cases of influenza vaccine, it did not achieve good results in obese patients."

Increasing doses

It is possible that ways will be found to compensate for the shortcomings in the effect of vaccines on obese patients, as is the case with the success of researchers' efforts to improve vaccine response rates among the elderly. Prof Ryan says giving obese people extra doses of the vaccine is one possibility. “Maybe three shots instead of two, or maybe a bigger dose, but doctors shouldn’t hold back saying the vaccine won’t work.”

Cry of warning

Ultimately, Drucker noted, the world may need to wait for data from clinical studies to clarify the roadmap, but the wait may be nerve-wracking. Dr. Sosa Garcia and others hope that the association between COVID-19 and obesity may force some governments and health care systems to deal with the growing problems of obesity in their countries, saying: “If you were a public health official and realized that 40% of the population is at high risk, This data is a wake-up call.”