Category: COVID

Categories : COVIDTags :

Nearly 4 in 10 Swedish COVID Patients in ICUs had Obesity

On By ModernMedia
Photo by Siora Photography on Unsplash

People with obesity were overrepresented among adults in Sweden in intensive care for COVID during the first wave of the pandemic, with over twice the proportion as compared to the general population. 

The study, appearing in PLOS One, used  the Swedish Intensive Care Registry (SIR) tp the researchers identified all patients with COVID who were admitted to ICUs in Sweden during the initial wave of the pandemic, in spring and summer 2020. Where height and weight data were missing from SIR, this was supplemented directly from the ICUs and also through the Nationwide Passport Register.

Though people with obesity were identified early on as a risk group that was affected especially severely by COVID, this study contributes to a new, more detailed picture.

A total of 1649 individuals with COVID from ICUs around Sweden were included. All the participants were aged 18 and over; three-quarters were men; and pregnant women were excluded.

The results show that patients with obesity (BMI of 30 kg/m2 or more) were overrepresented among those with COVID receiving intensive care in Sweden, which was 39.4 %, compared to 16% in the general population .

A high BMI increased the risk of both serious illness with long stays in intensive care and of death. A link was found between BMI over 30 and a 50% increase in mortality risk, compared with the normal-weight group. Among those who survived, a BMI over 35 was associated with a more than doubled risk of intensive care for over 14 days. These analyses have been adjusted for age, gender, comorbidity, and state of health at ICU arrival.

“For individuals with COVID who are in intensive care, obesity means an increased risk of death, and among those who survive, obesity boosts the risk of intensive care lasting more than 14 days,” explained first author Lovisa Sjögren, researcher at Sahlgrenska Academy, University of Gothenburg. “Based on our results, obesity should be included as an important risk factor in COVID. Patients with obesity who suffer from COVID should be monitored closely.”

The study is based on the Swedish Intensive Care Register, and Dr Sjögren points out that high-quality registers are a basic precondition for studies of this type to be feasible.

Senior author Jenny M Kindblom, Associate Professor at University of Gothenburg added: “Some international studies have shown a connection between high BMI and the risk of becoming severely ill with COVID. We can now show this in a Swedish context, and with the advantage of having a fully up-to-date BMI value for every patient,” said.

At an early stage during the pandemic, the researchers who conducted the study were in touch with HOBS, a Swedish patient organisation for people living with overweight and obesity. Many members were concerned that a high BMI would elevate the risk of serious illness in COVID.

“At the time, there were no publications in the field, and the study was initiated to enable us to answer patients’ questions. We now hope as many people as possible will take the opportunity to get vaccinated, and that health services include BMI – as a risk factor and perhaps choose to exercise special vigilance in monitoring patients with obesity who are suffering from COVID,” said Prof Kindblom.

Source: University of Gothenburg

Categories : COVID Obstetrics & GynaecologyTags :

Post-COVID Vaccination Menstrual Changes Investigated

On By ModernMedia
Photo by Mat Napo on Unsplash

A paper awaiting peer review on the MedRxiv preprint server shows that menstrual changes in women receiving after the COVID vaccine are quite common.

Many people began sharing that they experienced unexpected menstrual bleeding after being vaccinated for COVID, an emerging phenomenon which was undeniable yet understudied.

Unfortunately, dismissal by medical experts fueled greater concerns, as both vaccine hesitant and anti-vaccine individuals and organisations began to conflate the possibility of short-term menstrual changes with long-term harms to fertility. Many influencers used this well-used framing of protecting women as a means of further anti-vaccine messages.

There are many plausible biological mechanisms that could explain a relationship between an acute immune challenge such as a vaccine, its corresponding and well-known systemic effects on haemostasis and inflammation, and menstrual repair mechanisms of the uterus. The uterine reproductive system is flexible and adaptable in the face of stressors. Examples include marathon running having short term influence on hormone concentrations in the short term; short-term calorie restriction that results in a loss of menstrual cycling can be overcome by resuming normal feeding; that inflammation influences ovarian hormones; and that psychosocial stressors can correspond to cycle irregularity and yet resilience can buffer one from these harms. Typhoid, Hepatitis B, HPV vaccines have all had menstrual irregularity associated with them.  

While sustained early stressors can influence adult hormone concentrations, short-term stressors resolve and do not produce long-term effects. This is quite different from the sustained immune assault of COVID itself: studies and anecdotal reports are already demonstrating that menstrual function may be disrupted long-term, particularly in those with long COVID.

In this sample, 42% of people with regular menstrual cycles bled more heavily than usual, while 44% reported no change, after being vaccinated. Among people who typically do not menstruate, 71% of people on long-acting reversible contraceptives, 39% of people on gender-affirming hormones, and 66% of post-menopausal people reported breakthrough bleeding. We found increased/breakthrough bleeding was significantly associated with age, other vaccine side effects such as fever or fatigue, history of pregnancy or birth, and ethnicity.

Many respondents who had post-vaccine changes did not have them until fourteen days or longer post-inoculation, which extends beyond the typical seven days of adverse symptom reporting in vaccine trials.

Source: MedRxiv

Categories : COVID Ethics and LawTags :

The Rise of Phony Stem Cell COVID Treatments

On By ModernMedia
SARS-CoV-2 virus. Source: Fusion Medical Animation on Unsplash

The global race to develop new stem cell-based COVID treatments during the pandemic was filled with violations of government regulations, inflated medical claims and distorted public communication, according to an article appearing in Stem Cell Reports.

While stem cell therapy has treatment applications for a limited range of diseases and conditions, at present no clinically tested or government-approved cell therapies are available for the treatment or prevention of COVID or long COVID.

Despite this, some clinics have started offering unproven and unsafe “stem cell” therapies that promise to prevent COVID by strengthening the immune system or improving overall health, according to lead author Laertis Ikonomou, PhD, associate professor of oral biology in the University at Buffalo School of Dental Medicine.

The article explores the negative effects that misinformation about cell therapies has on public health, as well as the roles that researchers, science communicators and regulatory agencies should play in curbing the spread of inaccurate information and in promoting responsible, accurate communication of research findings.

“Efforts to rapidly develop therapeutic interventions should never occur at the expense of the ethical and scientific standards that are at the heart of responsible clinical research and innovation,” said Prof Ikonomou.

Other investigators include Megan Munsie, PhD, professor of ethics, education and policy in stem cell science at the University of Melbourne; and 

Many of the studies on possible stem cell-based COVID treatments are at an early stage of investigation and further evaluation on larger sample sizes is required, says Munsie. However, the findings from preliminary studies are frequently exaggerated through press releases, social media and uncritical news media reports.

“Given the urgency of the ongoing pandemic, even the smallest morsel of COVID science is often deemed newsworthy and rapidly enters a social media landscape where—regardless of its accuracy – it can be widely shared with a global audience,” said Aaron Levine, PhD, associate professor of public policy at Georgia Institute of Technology..

Clinics selling such treatments sometimes use these findings and news reports to exploit the fears of vulnerable patients by unethically advertising unproven stem cell treatments benefits of boosting the immune system, regenerating lung tissue and preventing transmission of COVID, said co-author Leigh Turner, PhD, professor of health, society and behaviour at the University of California, Irvine.

Reportedly some harm to patients resulted from unproven stem cell therapies, including blindness and death. Patients suffer financially as well, said Prof Ikonomou, as the products range in price from a few thousand to tens of thousands of dollars, and people are often encouraged to receive the expensive treatments every few months.

Patients who COVID may decline vaccines, stop wearing masks and stop other COVID safety measures, Prof Turner warned. They may also be less likely to participate in ethically conducted clinical trials.

“The premature commercialisation of cell-based therapeutics will inevitably harm the field of regenerative medicine, increase risks to patients and erode the public’s trust,” said Prof Ikonomou.

Despite warnings, many offending companies continue to make false claims. The authors recommend that regulatory agencies consider implementing stronger measures.

They also suggest that scientific and professional societies lobby regulatory agencies to increase enforcement of laws and regulations. The authors recommended that science communicators and journalists can combat misinformation by not engaging in hyperbolic coverage of research results and conveying study limitations.

Source: University at Buffalo

Categories : COVIDTags :

Long COVID in More Than Half of Survivors

On By ModernMedia
Photo by Joice Kelly on Unsplash

More than half of the 236 million people diagnosed with COVID around the world will experience ‘long COVID’ up to six months after recovering, according to Penn State College of Medicine researchers.

During their illnesses, many patients with COVID experience symptoms, such as tiredness, difficulty breathing, chest pain, sore joints and loss of taste or smell.

There have been few studies focussing on patients’ health after recovering from COVID. The researchers examined worldwide studies involving unvaccinated patients who recovered from COVID in order to understand the short and long term impacts of infection. The study found that both adults and children can experience several adverse health issues for six months or longer after recovering from COVID.

The researchers conducted a systematic review of 57 reports that included data from 250 351 unvaccinated adults and children who were diagnosed with COVID from December 2019 through March 2021. Among those studied, 79% were hospitalised, and most patients (79%) lived in high-income countries. Patients’ median age was 54, and 56% were male.

Patients’ health post-COVID was analysed during three intervals at one month (short-term), two to five months (intermediate-term) and six or more months (long-term).

Survivors were found to experience an array of residual health issues associated with COVID,.which generally affected a patient’s general well-being, their mobility or organ systems. Overall, half of survivors experienced long-term COVID manifestations, and these rates remained largely constant from one month through six or more months after their initial illness.

Several trends were observed among survivors, such as:

  • General well-being: More than half of all patients reported weight loss, fatigue, fever or pain.
  • Mobility: Roughly a fifth of survivors had a decrease in mobility.
  • Neurologic concerns: Nearly one quarter of survivors had difficulty concentrating.
  • Mental health disorders: Nearly a third of patients were diagnosed with generalised anxiety disorders.
  • Lung abnormalities: Six in ten survivors had chest imaging abnormality and more than a quarter of patients had difficulty breathing.
  • Cardiovascular issues: Chest pain and palpitations were among the commonly reported conditions.
  • Skin conditions: Nearly a fifth of patients experienced hair loss or rashes.
  • Digestive issues: Stomach pain, lack of appetite, diarrhoea and vomiting were among the commonly reported conditions.

“The burden of poor health in COVID survivors is overwhelming,” said co-lead investigator Dr Paddy Ssentongo, assistant professor at the Penn State Center for Neural Engineering. “Among these are the mental health disorders. One’s battle with COVID doesn’t end with recovery from the acute infection. Vaccination is our best ally to prevent getting sick from COVID and to reduce the chance of long-COVID even in the presence of a breakthrough infection.”

The mechanisms behind long COVID remain little understood. These symptoms could result from immune-system hyperactivation, lingering infection, reinfection or an increased production of tissue-attacking autoantibodies. SARS-CoV-2 can access, enter and live in the nervous system, resulting in commonly occurring nervous system symptoms such as taste or smell disorders, memory impairment and decreased attention and concentration commonly.

Dr Ssentongo noted that the study did not rule out other causes from the symptom besides COVID.

Early intervention will be crucial for improving the quality of life for many COVID survivors, and in the years ahead, health care providers will likely see an influx of patients with psychiatric and cognitive problems, such as depression, anxiety or post-traumatic stress disorder who were otherwise healthy before contracting COVID. Healthcare systems in low- and middle-income countries risked being overwhelmed with 

“Since survivors may not have the energy or resources to go back and forth to their health care providers, one-stop clinics will be critical to effectively and efficiently manage patients with long COVID,” Dr Ssentongo said. “Such clinics could reduce medical costs and optimise access to care, especially in populations with historically larger health care disparities.”

Source: Penn State

Categories : COVID Obstetrics & GynaecologyTags :

Delta Variant Causes Pregnancy Complications

On By ModernMedia
Source: Anna Hecker on Unsplash

Pregnant women have been a population of concern for physicians since the beginning of the COVID pandemic, and early on the frequency of caesarean delivery, preterm birth and pregnancy-related hypertension was reported to be increased in pregnant women who developed severe or critical illness from the novel coronavirus.

In May and June this year, there was a lull in COVID cases and hospitalisations, to the relief of physicians at the University of Alabama at Birmingham Hospital and their pregnant patients. However, the Delta variant soon caused a rise in cases, hospitalisations and deaths across the US state of Alabama. Along with this there was a seemingly higher number of pregnant patients with COVID in hospitals and intensive care units than in previous surges.

“We saw an alarming increase in pregnant patients hospitalised with the Delta variant in July and August,” said Akila Subramaniam, MD, associate professor in UAB’s Division of Maternal-Fetal Medicine. “Even more, many of our patients were delivering pre-term because of the effects of the virus on these women.”

Researchers tracked admission rates and maternal and neonatal outcomes of pregnant COVID patients at UAB Hospital from March 22, 2020, to Aug. 18, 2021. Outcomes were compared between pre-Delta and Delta groups, with preliminary findings seriousindicating  morbidity and adverse outcomes associated with the Delta variant and pregnancy.

Prior to the Delta variant, UAB Hospital saw the highest admission of pregnant women with active COVID in July 2020. A total of 28 pregnant patients were admitted that month, three of whom were admitted to the intensive care unit. In comparison, 39 pregnant patients, with 11 in ICU, were hospitalised in just the first 18 days of August.

“Pregnant women are a high-risk population with low-vaccination rates overall,” said Jodie Dionne, MD, associate director of UAB Global Health in the Center for Women’s Reproductive Health and associate professor in the Division of Infectious Diseases. “There is misinformation circulating that causes doubt in the vaccines or downplays the effect of the virus. This study highlights how dangerous contracting the virus, especially the Delta variant, can be for the mom and baby.”

From the study’s early findings, the UAB researchers emphasize recommendations from the Society of Maternal-Fetal Medicine, the American College of Obstetricians and Gynecologists, and the Centers for Disease Control and Prevention to vaccinate pregnant patients to mitigate severe perinatal morbidity and mortality.

The findings were published in the journal of Obstetrics and Gynecology.

Source: University of Alabama at Birmingham

Categories : COVIDTags :

Kenya’s Waves Driven by Socio-economic Differences and Variants

On By ModernMedia
Phot by Martin Sanchez on Unsplash

By combining COVID surveillance data with population mobility data from smartphones, infectious disease modellers have explained the evolution of the first three COVID waves to hit Kenya. 

Sequential waves of transmission through different socio-economic groups, followed by infection boosted by the introduction of new variants.

In order to forecast future outbreaks, the team had to develop a model to explain current waves. The work brought together COVID antibody survey data, PCR case data, genomic variant data and Google mobility data, seeking to find an explanation to the waves of COVID in Kenya. The aim was to then provide policy-based forecasts on future waves in the country based on the model findings.

Lower socio-economic groups have been identified as vulnerable to SARS-CoV-2 in the global South due to living in densely populated informal settlements, with reduced access to sanitation, and relying on daily mobility for informal employment. In contrast, those from higher socio-economic groups with job security can work from home, physically distance and readily access water and sanitation, thereby decreasing transmission.
The modelling results show that differences in mobility and contact rates between high and low socio-economic groups within Kenya explain the differences between the first and second waves. In the initial phase of the epidemic (from March 2020), individuals in high socio-economic groups could reduce their mobility and contact rates, but individuals in lower socio-economic groups could not. This resulted in transmission among individuals in lower socio-economic groups that was observed as the first wave in urban centres. As these individuals recovered from infection and became immune, at least temporarily, the first wave ended.

By the onset of the second wave (from October 2020), individuals in high socio-economic groups had increased their contact rates and mobility. This led to transmission among individuals in the high socio-economic groups, and also involved rural as well as urban areas. The second wave then appeared to end as individuals cleared the virus and became immune, at least for the time being. However, the advent of the more infectious Beta and Alpha variants resulted in a third wave among both high and low socio-economic groups (from March 2021).

 In many other African countries, there have been multiple waves that are not fully explained by timing of restrictions, and as they have similar urban socio-economic groupings, the researchers speculate that these explanations may have wider applicability. Understanding the causation of such multiple waves is critical for forecasting hospitalisation demand and the likely effectiveness of interventions including vaccination strategy.

Dr Samuel Brand from the University of Warwick said: “This is one of the first studies to consider detailed predictions of the dynamics of COVID across multiple waves in tropical sub-Saharan Africa. We believe this sets a new standard for the type of public health modelling work that can be conducted in real-time in developing countries.”

Dr John Ojal of KEMRI-Wellcome Trust Research Programme said: “There are highly detailed modelling studies of this nature in High Income Countries, but there have been none previously in tropical sub-Saharan Africa.”

The study has been published in the journal Science.

Source: University of Warwick

Categories : COVIDTags :

Vaccinated Individuals Reduce COVID Risk for Nonimmune People

On By ModernMedia
Photo by Gift Habeshaw on Unsplash

As the number of family members with COVID immunity from prior infection or vaccination increased, there was a decrease in infection and hospitalisation risk for nonimmune people. 

This is shown in a Swedish study conducted by researchers at Umeå University and published in JAMA Internal Medicine.

“The results strongly suggest that vaccination is important not only for individual protection, but also for reducing transmission, especially within families, which is a high-risk environment for transmission,” said Peter Nordström, professor of geriatric medicine at Umeå University.

Evidence shows that vaccines greatly reduce the severity of COVID including the Delta variant but there less is known how vaccination affects transmission of the virus in high-risk environments, eg within families.

The researchers found that there was a dose-response association between the number of immune individuals in each family and the risk of infection and hospitalisation in non-immune family members. Specifically, non-immune family members had a 45 to 97% reduced risk of infection and hospitalisation, as the number of immune family members increased.

The study is a nationwide, registry-based study of more than 1.8 million individuals from more than 800 000 families, drawing on various databases. In the analysis, the researchers quantified the association between the number of family members with immunity against COVID and the risk of infection and hospitalisation in nonimmune individuals. The researchers accounted for factors such as differences in age, socioeconomic status, clustering within families, and several diagnoses previously identified as risk factors for COVID in the Swedish population.

“It seems as if vaccination helps not only to reduce the individual’s risk of becoming infected, but also to reduce transmission, which in turn minimises not only the risk that more people become critically il, but also that new problematic variants emerge and start to take over. Consequently, ensuring that many people are vaccinated has implications on a local, national, and global scale,” said study co-author Marcel Ballin, doctoral student in geriatric medicine at Umeå University.

Source: Umeå University

Categories : COVID ImmunologyTags :

Differences in Natural and Vaccine-induced COVID Immunity Revealed

On By ModernMedia
Source: Fusion Medical Animation on Unsplash

A new study recently published in Nature has found that immune protection resulting from COVID protection creates lasting effects in memory B cells.

Unlike circulating antibodies, which peak soon after vaccination or infection only to fade a few months later, memory B cells can remain to ward off severe disease for decades. They also evolve over time, learning to produce successively more potent ‘memory antibodies’ that are more effective at neutralising the virus and with better adaptation to variants.

Though vaccination instils higher levels of circulating antibodies than natural infection, the study suggests that not all memory B cells are created equal. While vaccination gives rise to memory B cells that evolve over a few weeks, natural infection births memory B cells that continue to evolve over several months, producing highly potent antibodies adept at eliminating even viral variants.

Though the findings suggest an advantage from natural infection over vaccination, this does not outweigh the dangers of illness and death from COVID, the researchers warn.

“While a natural infection may induce maturation of antibodies with broader activity than a vaccine does – a natural infection can also kill you,” explained Professor Michel C. Nussenzweig, head of Rockefeller’s Laboratory of Molecular Immunology. “A vaccine won’t do that and, in fact, protects against the risk of serious illness or death from infection.”

When any virus enters the body, immune cells immediately release circulating antibodies, which decay at variable rates depending on the vaccine or infection. They may confer protection for months or years but then dwindle in number, allowing possible reinfection.

Long term protection is provided by memory B cells that produce memory antibodies. Studies suggest that memory B cells for smallpox last at least 60 years after vaccination; those for Spanish flu, nearly a century. And while memory B cells don’t necessarily block reinfection, they can prevent severe disease.

Recent studies have suggested that within five months of receiving a vaccine or recovering from a natural infection, some no longer retain sufficient circulating antibodies to keep the novel coronavirus at bay, but memory B cells remain vigilant. Until now, however, scientists did not know whether the vaccines could be expected to provide the sort of robust memory B cell response seen after natural infection.

Prof Nussenzweig and colleagues resolved to tease out any differences in memory B cell evolution by comparing blood samples from convalescent COVID patients to those from never-infected mRNA-vaccinated individuals.

Vaccination and natural infection elicited similar numbers of memory B cells, which rapidly evolved between the first and second dose of the Pfizer and Moderna vaccines, producing increasingly potent memory antibodies. But after two months, progress stalled. The memory B cells were present in large numbers and expressed potent antibodies, but the antibodies were not getting any stronger. Also, although some of these antibodies were able to neutralize Delta and other variants, there was no overall improvement in breadth.

The researchers found that in convalescent patients, however, memory B cells continued to evolve and improve up to one year after infection. With every memory B cell update, more potent and more broadly neutralising memory antibodies were coming out.

There are several potential reasons that memory B cells produced by natural infection might be expected to outperform those produced by mRNA vaccines, the researchers said.

It is possible that the body responds differently to viruses that enter through the respiratory tract than those that are injected. Or perhaps an intact virus goads the immune system in a way the vaccines’ spike protein antigens simply cannot. It may also be possible that the virus persists in the naturally infected for weeks, giving the body more time to mount a robust response. The vaccine, on the other hand, is flushed out of the body mere days after triggering the desired immune response.

Memory B cells appear to undergo limited bouts of evolution in response to mRNA vaccines, a finding which may have significant implications for booster shots. A booster with the current mRNA vaccine would likely stimulate memory cells to produce antibodies strongly protective against the original virus and somewhat less so against the variants, Prof Nussenzweig said.

“When to administer the booster depends on the object of boosting,” he said. “If the goal is to prevent infection, then boosting will need to be done after 6 to 18 months depending on the immune status of the individual. If the goal is to prevent serious disease, boosting may not be necessary for years.”

Source: Rockefeller University

Categories : COVIDTags :

Digital COVID Vaccination Certificates for South Africa are Here

On By ModernMedia
Photo by Priscilla Du Preez on Unsplash

People vaccinated in South Africa can now download their digital COVID vaccination certificates. The service officially went live on Friday, and was announced by the Minister of Health, Dr Joe Phaahla.

Addressing a media briefing, Dr Phaahla said the certificate could be used for travel and tourism, sport and recreation events, music festivals, shops that are providing discounts and prizes for people who are vaccinated.

“Our role is to make this tool available to the nation to provide people with the proof of vaccination so they can have access to the many amenities and activities that some have been missing…

“The vaccination certificate was introduced over the last three days while it was in the testing phase but some people have been able to upload it to their cell phones.

“We are launching the first phase of the certificate – there’s going to be a lot more improvements in the next two months [with regards to] the safety and security of the certificate but it is ready for use,” said the Minister.

The certificate was developed by the Department of Health and the Council for Scientific and Industrial Research (CSIR) and can be found at https://vaccine.certificate.health.gov.za.

The project manager for the National Electronic Vaccination Data System (EVDS), Milani Wolmarans, said the certificate can be downloaded through a web portal by anyone who has received the COVID vaccine in South Africa.

“You’ll need your vaccination code from the SMS you received after your vaccination, South African ID or Foreign Passport number or Asylum or Refugee number. This should be the same document that you presented when you got vaccinated and the cell phone you included on your registration,” she said.

Vaccination codes will be sent via SMS over the next four day, and also be accessed from the COVID call centre on 0800 029 999.

“With regards to the recognition of the digital certificate, most countries around the globe would accept the certificate. It is, however, dependent on the policy of the country that you would be visiting and also what their verification requirements would be.

“Towards the end of the next two months, there will be an app that you can use to download the certificate,” Wolmarans said.

The Minister also welcomed South Africa’s removal from the UK’s red list, which will take effect on Monday 11 October.

“We are also pleased with the UK government announcement that it is taking our country from the red list – meaning more easy travel between people from South Africa and the UK. The UK will be recognising the certificate that we are launching,” Dr Phaahla said.

Importantly, the UK will also now recognise South African COVID vaccination certificates.

Source: SA News.Gov

Categories : COVID Substance UseTags :

People With Substance Use Disorder at Higher Risk for COVID

On By ModernMedia
Source: Unsplash CC0

A recent study showed that people with substance use disorders (SUDs) face higher risks for developing COVID and for experiencing serious problems associated with the infection. The study, published in World Psychiatry, examined these risks in fully vaccinated individuals with SUDs.

The study included 579 372 people in the US, of whom 30 183 had a diagnosis of SUD and 549 189 without such a diagnosis) who were fully vaccinated between December 2020 and August 2021 and had not contracted COVID before their vaccinations.

The risk for breakthrough COVID infection in vaccinated people with SUDs ranged from 6.8% for tobacco use disorder to 7.8% for cannabis use disorder, all significantly higher than the 3.6% in the vaccinated non-SUD population. After controlling for demographics (age, gender, ethnicity) and vaccine types (Pfizer, Moderna, Johnson & Johnson), patients with SUDs – with the exception of those with tobacco use disorder – still had higher risks for breakthrough COVID-19 compared with matched individuals without SUDs, with the highest risks for those with cocaine use disorder and cannabis use disorder. 

The higher risk for people with SUDs was found to be largely due to their higher prevalence of comorbidities and adverse socioeconomic determinants of health (such as problems related to education, employment, and housing). However, those with cannabis use disorder, who were younger and had less comorbidities, still had a higher risk for breakthrough infection even matching for these. This could indicate that other variables, such as behavioural factors or adverse effects of cannabis on pulmonary and immune function, could explain some of their higher risk for breakthrough infection.

“In our study, the overall risk of COVID infection among vaccinated SUD patients was low, highlighting the effectiveness and the need for full vaccination in this population,” the authors wrote. “However, our findings document that this group remains a vulnerable one even after vaccination, confirming the importance for vaccinated patients with SUD to continue to take protective preventive measures against the infection.”

Source: Wiley