According to public health
experts, antibiotic misuse and overuse during the pandemic could exacerbate
another ongoing crisis: antibiotic resistance, in which pathogens such as
bacteria and fungi evolve to resist powerful drugs designed to kill them.
Antibiotic-resistant diseases kill more than 750,000 people each
year, with the figure expected to rise to 10 million by 2050.
Antibiotic-resistant bacteria can cause about 2.8 million infections and over 35,000 deaths in the United States alone each year.
Antibiotic overuse during the COVID-19 pandemic may now be
compounding the situation. When COVID-19 author describes coughing, fever,
shortness of breath, and chest X-rays indicated white spots—lung inflammation
resembling bacterial pneumonia—many were offered antibiotics in the early
months of the pandemic. For example, more than half of the approximately 5,000
patients admitted to hospitals in the United States between February and July
2020 were given at least one antibiotic within the first 48 hours of their
stay.
"When dealing with uncertainty, you err on the side of
prescribing, which isn't always the best thing to do," says Jacqueline
Bork, an infectious disease physician at the University of Maryland Medical
Center.
Antibiotics are only effective against bacteria, not viruses such
as SARS-CoV-2, which causes COVID-19. However, pneumonia can be caused by
fungi, bacteria, or viruses. Identifying which pathogen is to fault can take up
to 48 hours and may need invasive tests to determine the infection's source.
Sometimes the tests fail to identify the cause of the problem. "It's
likely that many of us were overprescribing antibiotics. But, given the absence
of a clear understanding of the situation, we did the best we could at the
time," Bork says.
Some doctors were also concerned that, as with influenza and other
viral infections, a fungal or bacterial infection could develop during or
following COVID-19. "We couldn't even screen for viral versus bacterial
illness at first because there were so many people who came in with
pneumonia," Bork explains.
When she and other doctors across the world discovered that only
about 20% of COVID-19 patients had fungal and bacterial co-infections, they
reduced their antibiotic use. Antibiotics were required for patients who were
critically ill. They were in hospitals for more extended periods, often with
breathing tubes and catheters that cause bacterial infections and sepsis.
Despite this, doctors in many parts of the world continued to
provide antibiotics to COVID-19 patients who didn't need them. Patients had
resorted to self-medicating with antibiotics when they could not consult
doctors, sometimes even as a preventive step. Overuse and misuse of antibiotics
may have occurred during the pandemic due to the high cost and lack of access
to diagnostic tests that establish bacterial illness and hence the necessity
for antibiotics, a "just-in-case" attitude, and sometimes a lack of
knowledge about the latest science.
How does antimicrobial resistance develop
Antibiotics are chemicals produced by soil-dwelling fungi and
bacteria that kill or hinder the growth of other bacteria competing for the
same limited resources. The targets adapt over time by developing resistance
against such an arsenal. They accomplish this by producing enzymes, which
inactivate antibiotics, drain antibiotics from bacterial cells, block
antibiotic entry, or bypass their effects. Other bacterial species that weren't
primarily aimed by antibiotics can sometimes evolve defenses by acquiring
relevant genes from nearby resistant bacteria through a process known as
horizontal gene transfer.
Researchers have developed commercial antibiotics based on natural
antibiotics that fight bacterial illnesses in humans and animals. However, some
of these infection-causing bacteria in water and soil may have already gained
resistance genes.
Such resistant bacteria make up a small percentage of the
bacterial population in host bodies at first, but this changes as antibiotic
use increases. The medicine kills susceptible bacteria, eliminating competition
and allowing resistant germs to proliferate and thrive quickly. In addition,
giving incorrect antibiotic doses or misusing them, such as for the wrong
condition, can kill healthy bacteria in our bodies and foster the spread of
antibacterial drugs superbugs.
These drug-resistant bacteria can spread by sewage, polluted
water, surfaces, and food—or through direct contact—in hospitals, communities,
animals, and poultry farms. As more individuals become infected with superbugs,
current antibiotics become less effective, resulting in more extended hospital
stays, more medical costs, and more deaths. This is especially concerning for
low- and middle-income countries, which are disproportionately affected by
limited access to clean water and sanitation, quality healthcare, and
over-the-counter access to generic antibiotics, encouraging self-medication
when consultation is costly.
How COVID-19 may exacerbate multi-drug resistant infections
During the pandemic, 35 of 56 nations reported an increase in
antibiotic prescribing, according to a global survey done by the World Health
Organization in late 2020. Antibiotics were prescribed in practically all
COVID-19 instances in one country, and self-medicating with these drugs was
widespread in another.
Antibiotics such as azithromycin, doxycycline, fluoroquinolones,
cephalosporins, and carbapenems have been prescribed to COVID-19 patients in
hospitals. Although some studies have shown that bacterial or fungal
co-infection or secondary infection rates among COVID-19 patients are less than
20%, they've frequently utilized broad-spectrum antibiotics that kill a variety
of bacteria, including helpful bacteria. Antibiotics such as azithromycin and
doxycycline have been prescribed to outpatients with mild COVID-19 symptoms.
A few studies suggested taking azithromycin and doxycycline early
in the pandemic because of their antiviral and anti-inflammatory properties,
which could help calm a COVID-19 patient's hyperactive immune system when it
starts destroying its cells. However, more recent research has found no real
benefits.
"A lot of COVID-19 patients come to me for a second opinion,
and I see azithromycin on their prescriptions even now," says Lancelot
Pinto, a pulmonologist at Mumbai's P.D. Hinduja Hospital. "Perhaps the
justification is that there's a chance of a bacterial infection, so it's better
to be covered," she says, "but I don't think many physicians [in
India] care if it's a virus or not when prescribing antibiotics."
In other cases, physicians have been compelled to prescribe
azithromycin in remote areas where, for example, diagnostic testing such as
X-rays are unavailable to confirm pneumonia, let alone determine whether the
etiology is bacterial, fungal, or viral.
"When individuals aren't as sure of themselves, they think
it's better to provide it just in case," says Rumina Hasan, a pathologist
at the Aga Khan University in Karachi, Pakistan. She also points out that
disconnected physicians or unable to keep up with current COVID-19 information
contributed to the improper overuse of antibiotics during the epidemic.
"And it's tough to change a trend [of using certain treatments against a
disease] once it's established," Hasan explains.
Antibiotics can save lives when used correctly, but global health
experts believe that their extensive and indiscriminate use during the epidemic
may have produced the perfect storm for resistant bacteria to emerge.
In the future
We may not see the rise of superbugs and their effects right away,
but "the harm is done," says Pilar Ramon-Pardo, Pan American Health
Organization's regional advisor on antibiotic resistance. During the pandemic,
the WHO's Global Antimicrobial Resistance and Use Surveillance System took a
hit due to a shortage of medical staff worldwide who could collect samples and
report on drug-resistant microbes.
There's a budget shortage, and mental fatigue as all resources are
devoted to defeating COVID-19. "People don't want to hear about yet
another public health crisis," says Muhammad Zaman, a Boston University,
professor of biomedical engineering. "Something has to give," says
the speaker.
Should we expect new antibiotics to fight antibiotic-resistant
illnesses if they become more common in the post-pandemic world? According to
Zaman, there aren't likely to be as many. Antibiotic courses are rarely longer
than 14 days, and they don't earn pharmaceutical companies as much money as
therapy for common diseases like cancer and diabetes. New drugs are also more
likely to encounter drug resistance sooner rather than later, making innovation
less lucrative.
The National Institutes of Health, on the other hand, created an
antibacterial resistance initiative in 2013 to conduct and fund research aimed
at evaluating novel medications and diagnostic tools as well as improving the
use of existing antibiotics. According to global health experts, the solution
is to improve infection prevention and control. Vaccines against drug-resistant
diseases that are now being developed could also be promising.
"However, the idea that this is merely a scientific issue is both incomplete and misleading," Zaman argues. "We need to consider economics, availability, and human behavior."