Tag: Virus

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Severe COVID-19 increases risk of future cardiovascular events

Study: COVID-19 severity and risk of subsequent cardiovascular events. Image Credit: Yurchanka Siarhei / Shutterstock.com

To date, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the virus responsible for the coronavirus disease 2019 (COVID-19), has infected over 603 million individuals and claimed more than 6.4 million lives worldwide.

About 30% of COVID-19 survivors continue to experience a wide range of persistent symptoms for several weeks since their initial diagnosis. This condition is commonly referred to as post-acute sequelae of SARS-CoV-2 infection (PASC) or “long COVID.”

Study: COVID-19 severity and risk of subsequent cardiovascular events. Image Credit: Yurchanka Siarhei / Shutterstock.com

Study: COVID-19 severity and risk of subsequent cardiovascular events. Image Credit: Yurchanka Siarhei / Shutterstock.com

Background

Even though multisystem inflammatory syndrome is the most common PASC syndrome in adults and children, a wide range of other symptoms, including sleep difficulties, persistent fatigue, type 1 diabetes, and neurological disorders, have been reported. The incidence of these symptoms varies from one person to another based on their demographic and clinical characteristics.

Several studies have indicated the manifestation of multiple cardiovascular complications, such as arrhythmia, hypertension, acute myocardial infarction, thromboembolism, and cerebrovascular accidents, in individuals who have recovered from COVID-19. However, a limited number of studies have confirmed that severe COVID-19 leads to a high risk of cardiovascular diseases.

A recent Clinical Infectious Diseases journal study determines the relationship between COVID-19 severity and risk of subsequent cardiovascular events (CVEs) in a large cohort.

Study findings

A retrospective cohort study was performed using nationwide health insurance claims data of adults from the United States Health Verity Real-Time Insights and Evidence database. Increased COVID-19 severity was found to enhance the risk of developing subsequent CVEs among individuals without a cardiac history in previous years. 

As compared to COVID-19 patients who required outpatient care, those who required hospital admission were more likely to experience CVEs. Among COVID-19 hospitalized patients, those admitted to the intensive care unit (ICU) were almost 80% more likely to develop CVEs than non-ICU hospitalized patients.

In fact, non-ICU hospitalized patients exhibited only a 28% possibility of experiencing CVEs thirty days after initial COVID-19 symptoms. Additionally, as compared to COVID-19 outpatients, hospitalized patients were more likely to be admitted for a CVE after recovering from COVID-19.

In younger adults, the incidence of cardiovascular sequelae was lower as compared to older adults. Aside from CVEs, other severe outcomes, such as thrombotic events and cerebrovascular accidents, were observed in patients who recovered from severe COVID-19. However, such observations were less likely in COVID-19 patients who required only outpatient care.

The study findings emphasize the importance of vaccination, as demonstrated by its ability to reduce severe disease. Similarly, prompt antiviral treatment of acute COVID-19 has been recommended, which would help reduce the possibility of transition to severe illness.

Both COVID-19 vaccination and timely therapeutic interventions would alleviate the risk of severe COVID-19 and subsequently decrease the possibility of experiencing CVEs.

The findings of the present study are consistent with previous research that has reported a higher incidence of myocarditis and pericarditis in patients who recovered from severe SARS-CoV-2 infection. Nevertheless, it was observed that elevated cardiovascular risk after acute infection may not be exclusive to COVID-19.

In fact, some other diseases that have been associated with an increased risk of long-term CVEs are influenza and pneumonia bacteremia. Additionally, 22-65% of sepsis survivors are at an increased risk of CVEs.

The underlying mechanism responsible for the increased risk of CVEs following SARS-CoV-2 infection has not been determined. SARS-CoV-2 infects cardiac myocytes through their interaction with the angiotensin-converting enzyme 2 (ACE-2) receptor, which might remain persistent; therefore, this interaction induces chronic inflammatory responses and subsequent tissue damage or fibrosis.

Another mechanism related to the development of CVEs following recovery from COVID-19 is an autoimmune response to cardiac antigens that causes delayed damage to cardiac tissues. Anti-heart antibodies also correlated with cardiovascular manifestation and COVID-19.

Viral toxicity is another possible mechanism that might cause long-term cardiac damage or thrombosis in vasculitis. However, in the future, more research is needed to confirm the mechanisms related to cardiac damage after SARS-CoV-2 infection.

Conclusions

Due to the lack of a COVID-19-negative control group, the authors failed to quantify the elevated risk of CVEs in COVID-19 patients. The unwanted inclusion of patients with a history of CVEs could have overestimated the result as well. The impact of vaccination status on the incidence of CVE was not studied.

Despite these limitations, the present study strongly emphasized that patients who recovered from severe COVID-19 were at a greater risk of developing CVEs. As compared to COVID-19 patients who required outpatient care, those who were admitted to the ICU were at a higher risk of experiencing CVEs.

The importance of COVID-19 vaccination in preventing severe infection was strongly emphasized in this study.

Journal reference:

  • Wiemken, L. T., McGrath, L. J., Andersen, K. M., et al. (2022). COVID-19 severity and risk of subsequent cardiovascular events. Clinical Infectious Diseases. doi:10.1093/cid/ciac661.
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Monkeypox spreading locally at large LA County events, health officials say

Monkeypox spreading locally at large LA County events, health officials say

The number of confirmed monkeypox cases in Los Angeles County has jumped to 22, which health officials said has largely been spread among men who have sex with other men who have recently attended large events.

Most of the recent cases involve individuals who have not traveled out of the country or out of the state, as was the situation in most of the first identified cases in the US.

No hospitalizations or deaths have been reported, officials said.

“Anyone can get and spread monkeypox, but some of the recent cases identified have been among gay, bisexual, and other men who have sex with men who attended large events where the exposure to monkeypox may have occurred,” the Los Angeles Department of Public Health said in a statement on Friday. “Public Health is working with event organizers to notify attendees of potential exposure.”

Monkeypox
Around 25% of the number of US cases of Monkeypox are in California.
Getty Images

The department said it would be JYNNEOS vaccine, targeting “individuals at higher risk of monkeypox,” which includes those who have had close contact with an infected person and those who were at an event where they may have had “skin-to-skin” contact with an infected person.

The department said it would be working to make the hard-to-come-by vaccine available for other high-risk groups as supplies increase.

Monkeypox is a viral infection that causes skin lesions and is endemic in certain parts of Africa. But the current outbreak has hit countries like the US and United Kingdom where the virus does not usually spread, sparking global concern.

The virus can cause blisters, pimples and rashes on the skin. Most who contract monkeypox report only mild illness that goes away within two-to-four weeks without treatment.

Monkeypox can spread through contact of bodily fluids, monkeypox sores or clothing with an infected person, according to the Centers for Disease Control and Prevention. It can also be contracted by breathing in respiratory droplets while speaking to someone.

The CDC said there have also been reports of transmission among family members and close contacts.

On Saturday, the US surpassed 200 confirmed cases nationwide, 51 of which are in California, according to the CDC’s latest data.

The White House announced earlier in the week that tests for the virus will be shipped to commercial laboratories to expand testing and speed up diagnoses.

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COVID-19 superspreader events typically originate from few carriers

Study: Analysis of overdispersion in airborne transmission of COVID-19. Image Credit: oxinoxi / Shutterstock

A recent research paper published in the journal Physics of Fluids analyzed the overdispersion in the coronavirus disease 2019 (COVID-19) airborne transmission.

Study: Analysis of overdispersion in airborne transmission of COVID-19. Image Credit: oxinoxi / ShutterstockStudy: Analysis of overdispersion in airborne transmission of COVID-19. ​​​​​​​Image Credit: oxinoxi / Shutterstock

Background

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been characterized by overdispersion and superspreading events comparable to SARS and other respiratory virus outbreaks. Any incident that results in more than the typical number of secondary transmissions is referred to as superspreading.

Overdispersion is a non-random trend of grouping in the context of contagious diseases, which frequently involves a large proportion of zero cases and a limited percentage of large outbreaks.

Nevertheless, the specific functions and influences of established physical and viral factors correlated to transmission processes on overdispersion are still unknown. Moreover, the characteristics and nature of superspreading episodes are instrumental in explaining the spread of SARS-CoV-2. To date, mechanistic simulations depicting airborne transmission have not been combined with real-world occupancy and distribution data to better explain large-scale characteristics of disease dynamics, such as transmissibility overdispersion.

About the study

In the present study, the authors used real-world occupancy information from over 100,000 social contact contexts in 10 United States (US) metropolises to undertake mechanistic modeling of COVID-19 point-source transmission via infectious aerosols. The primary purpose of this study was to use the molecular basis of airborne disease transmission to investigate event-level SARS-CoV-2 spread overdispersion utilizing real-world data from a significant number of social engagements.

The team tried to establish an algorithm centered on aerosol dispersion with randomized data and obtainable occupancy information to derive the distribution of the number of secondary infections for every infectious case. They investigated whether observed trends of overdispersion in secondary transmissions could be replicated through simulations utilizing the above algorithm.

Further, the scientists aimed to develop an analytical function (rather than a fit) that may explain the probability density function of the number of secondary infections arising from the dynamics of the problem. Furthermore, they attempted to determine the dominant factors that cause overdispersion and the consequences for mitigation strategies.

To achieve this, the scientists used 100,000 random social-contact conditions to solve an aerosol dispersal model by combining real-world area and occupancy data with practical ventilation and viral load rate to attain the probability distributions for the number of secondary infections for each infectious case in those situations.

Results and discussions

According to the simulated results, the aerosol transmission pathway was compatible with overdispersed individual COVID-19 infectivity. In addition, with exposure time, ventilation rate, and speaking time, SARS-CoV-2 load fluctuation was the most substantial factor controlling secondary attack rates. According to the authors, they, for the first time, generated analytical equations that precisely characterized the modeled probability density functions of secondary attack and infection rates. Besides, the generated analytical expressions revealed how the quantitative link among personal-level viral load variance and event-level occupancy governs overdispersion simultaneously.

These findings reveal that even in the case of airborne transmission, about 4% of index cases in indoor contexts were responsible for 80% of secondary cases, underlining the need for identifying and concentrating mitigation efforts on superspreading event causes. The results emphasize the significance of interventions, including isolation through rapid testing to identify intense viral shedding periods, for reducing exposures during stages of heightened viral shedding, improved ventilation, and the higher likelihood of outbreaks with SARS-CoV-2 variants of concern (VOCs) correlated with superior viral loads. Ultimately, considering viral burden and occupancy over indoor environments, the present analytical function may predict the spatially specified likelihood of outbreaks and outbreak magnitude via point-source transmission events.

Conclusions

Overall, the study findings demonstrated that around 4% of COVID-19 index cases possibly caused 80% of secondary SARS-CoV-2 infections, resulting in an extended tail probability distribution function of secondary infections per infectious event. Overdispersion appears to be notably driven by personal-level heterogeneity in SARS-CoV-2 load, with occupancy coming in second. The team then developed an analytical function that mimics the modeled SARS-CoV-2 overdispersion. Further, they illustrated the efficacy of potential COVID-19 mitigation techniques using this analytical function.

The present analysis adds a relevant dimension to the growing body of proof regarding SARS-CoV-2 airborne transmission by linking the mechanistic insights of COVID-19 aerosol spread with reported large-scale epidemiological features of outbreaks and thus unfolds as a potent tool for evaluating the likelihood of epidemics and the possible effects of mitigation actions on extensive disease dynamics. The simulation in this article covers overdispersion in the number of secondary cases rendered by each infectious case over an hour in such 100000 instances, assuming one index case at each site. The team mentioned that when combined with appropriate data, the current analytical expressions created and confirmed using simulations could explain overdispersion through drastically broader timeframes and contact vicinities.

Journal reference:

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Microbix Presenting Respiratory Virus Controls Data at Two Events

Microbix Presenting Respiratory Virus Controls Data at Two Events

QAPs Supporting Tests That Simultaneously Detect Multiple Respiratory Viruses

MISSISSAUGA, Ontario, April 19, 2022 (GLOBE NEWSWIRE) — Microbix Biosystems Inc. (TSX: MBX, OTCQX: MBXBF, Microbix®), a life sciences innovator, manufacturer, and exporter, announces it will be presenting performance results of its quality assessment products (“QAPs™”) that support molecular-diagnostic (“MDx”) screening-tests for respiratory viruses at two industry congresses – “Labquality Days” in Helsinki, Finland April 20-21, 2022 and “ECCMID 2022” in Lisbon, Portugal, April 23-26, 2022.

Labquality Days is an annual international congress focusing on quality in laboratory medicine and medical devices. It is sponsored by Labquality Oy, a well-established Scandinavian clinical-lab proficiency and accreditation authority that is also a Microbix distribution partner. ECCMID 2022 is the 32nd annual congress organized by the European Society of Clinical Microbiology and Infectious Diseases.

At these events Microbix will be presenting performance results of its QAPs for support of MDx tests that detect multiple respiratory viruses from a single patient-sample. At Labquality Days, Microbix’s presentation is titled “Microbix’s Cross-Platform Compatible Respiratory Virus Multiplex Samples for use as a Quality Management Tool in Laboratory Syndromic Testing.” At ECCMID, Microbix’s presentation is titled “Respiratory Virus Multiplex Formulations Desiccated on Copan’s FLOQSwab® for use as Cross-Platform Compatible EQA Samples and Laboratory Quality Controls.” Microbix gratefully acknowledges the assistance of its six collaborator firms in planning and executing these evaluations. The posters will be available on Microbix’s website (https://microbix.com) following their presentation.

The two poster presentations detail the performance of three Microbix “multiplex” QAPs that each support testing for three to four pathogens, collectively providing quality management support of testing for 11 common respiratory viruses – Adenovirus, Enterovirus, Influenza A, Influenza B, Metapneumovirus, Parainfluenza 2, Parainfluenza 3, Respiratory Syncytial Virus, Rhinovirus, SARS-CoV-2 (a.k.a., COVID-19), and Seasonal Coronavirus OC43. Each of these 11 viruses continue to cause widespread human disease.

These QAPs support the new-generation diagnostics that simultaneously detect multiple pathogens from a single patient sample – referred to as “multiplex” tests. By establishing the precise cause of disease symptoms, multiplex tests help enable better patient-care while also providing public health with intelligence on institutional or community prevalence of pathogens. Multiple new multiplex MDx tests are also suitable for use outside clinical laboratories – at point-of-care (“POC”) sites such as clinics or pharmacies – and thereby provide easier access to care and faster test results. Microbix “PROCEEDx™FLOQ®” and “REDx™FLOQ®” QAPs formatted onto Copan® FLOQSwabs® are ideal for supporting POC tests, as they fully-emulate test-workflows and are room-temperature stable.

Purchase enquiries for Microbix’s QAPs can be e-mailed to customer.service@microbix.com.

About Microbix Biosystems
Microbix develops proprietary biological technology solutions for human health and well-being, with over 100 skilled employees and sales now approaching C$ 2.0 million per month. It makes a wide range of critical biological materials for the global diagnostics industry, notably antigens for immunoassays and its laboratory quality assessment products (QAPs™) that support clinical lab proficiency testing, enable assay development and validation, or help ensure the quality of clinical diagnostic workflows. Microbix antigens enable the antibody tests of over 100 international diagnostics companies, while its QAPs are sold to clinical laboratory accreditation organizations, diagnostics companies, and clinical laboratories. Microbix QAPs are now available in over 30 countries, distributed by 1WA (Oneworld Accuracy Inc.), Alpha-Tec Systems, Inc., Diagnostic International Distribution SpA., Labquality Oy, The Medical Supply Company of Ireland, R-Biopharm AG, SDT Molecular Pte Ltd, Seegene Canada Inc., and Thomas Scientific LLC. Microbix is ISO 9001 and 13485 accredited, U.S. FDA registered, Australian TGA registered, Health Canada establishment licensed, and provides CE marked products.

Microbix also applies its biological expertise and infrastructure to develop other proprietary products and technologies, most notably viral transport medium (DxTM™) to stabilize patient samples for lab-based molecular diagnostic testing and Kinlytic® urokinase, a biologic thrombolytic drug used to treat blood clots. Microbix is traded on the TSX and OTCQX, and headquartered in Mississauga, Ontario, Canada.

Forward-Looking Information
This news release includes “forward-looking information,” as such term is defined in applicable securities laws. Forward-looking information includes, without limitation, discussion of Labquality Days, Labquality, or ECCMID 2022, the posters or their relevance, the products of Microbix or its collaborators, Microbix’s business and business results, goals or outlook, risks associated with financial results and stability, development projects such as those referenced in its corporate presentation, regulatory compliance and approvals, sales to foreign jurisdictions, engineering and construction, production (including control over costs, quality, quantity and timeliness of delivery), foreign currency and exchange rates, maintaining adequate working capital or raising further capital on acceptable terms or at all, and other similar statements concerning anticipated future events, conditions or results that are not historical facts. These statements reflect management’s current estimates, beliefs, intentions and expectations; they are not guarantees of future performance. The Company cautions that all forward-looking information is inherently uncertain and that actual performance may be affected by a number of material factors, many of which are beyond the Company’s control. Accordingly, actual future events, conditions and results may differ materially from the estimates, beliefs, intentions and expectations expressed or implied in the forward-looking information. All statements are made as of the date of this news release and represent the Company’s judgement as of the date of this new release, and the Company is under no obligation to update or alter any forward-looking information.

Please visit https://microbix.com or www.sedar.com for recent Microbix news and filings.

For further information, please contact Microbix at:

Cameron Groome,
CEO
(905) 361-8910		 Jim Currie,
CFO
(905) 361-8910		 Deborah Honig,
Investor Relations
Adelaide Capital Markets
(647) 203-8793
ir@microbix.com 		Jim Macdonald,
Investor Relations
Torrey Hills Capital
(858) 456-7300
jm@sdthc.com

Copyright © 2022 Microbix Biosystems Inc.
Microbix®, DxTM™, Kinlytic®, and QAPs™ are trademarks of Microbix Biosystems Inc.
PROCEEDx™FLOQ® and REDx™FLOQ® are trademarks of Microbix Biosystems Inc. in collaboration with Copan Italia S.p.A.
Copan®, FLOQ®, and FLOQSwab® are trademarks of Copan Italia S.p.A.

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Attendance plummets at LA covid vaccination events

Attendance plummets at LA covid vaccination events

Nurse Angel Ho-king sways her head to the sound of salsa music as she waits for people willing to roll up their sleeves to get a shot. Ho-king is part of a four-person crew staffing a covid-19 vaccine table at a health fair in Rampart Village, a predominantly immigrant neighborhood about 10 minutes from Dodger Stadium.

In three hours on a recent Saturday, Ho-king and Brenda Rodriguez, a medical assistant, vaccinated 16 people — far fewer than they had anticipated. Nearly everyone who showed up at the fair, organized by Saban Community Clinic, was an adult seeking a booster shot or a young child getting a first dose (children ages 5 to 11 became eligible for a vaccine late last year).

As covid infections have declined so too has interest in covid vaccines — even though the shots are highly effective at preventing serious illness and death from the virus.

In California’s most-populous county, where more than 1.7 million people have not received even one dose, vaccination events have turned desolate. About 46,000 county residents got their first dose in March, a 79% decline from January, according to the Los Angeles County Department of Public Health.

Those who remain unvaccinated are harder to convince, telling health care workers and vaccination coordinators that they don’t feel a sense of urgency.

According to a January survey by the Public Policy Institute of California, about 1 in 10 California adults said they definitely won’t get vaccinated, which has remained consistent since January 2021, and 86% of unvaccinated adults said the omicron variant wasn’t enough to persuade them. Employers and businesses are dropping or rolling back vaccination mandates. And although proof of vaccination once offered perks like allowing people to go maskless indoors, face coverings are generally no longer required in California.

At a recent vaccination drive coordinated by an immigrant advocacy group in Palmdale, near Lancaster in northern LA County, only two people showed up over four hours, both for second doses. As of April 1, 25% of Palmdale residents ages 5 and up were unvaccinated, compared with 17% of county residents, according to county data.

Jorge Perez, Salva Organization‘s vaccine coordinator, spent a week promoting the event with his team, going door to door, visiting local businesses, and publicizing it on social media. At previous vaccine drives, “we got 42 people, then 20, then four,” said a disappointed Perez. “Now two.”

Perez reduced the number of staffers at vaccination events from five to two in February as the numbers started to dwindle.

Much work remains to be done to combat vaccine misinformation, especially given the spread of BA.2, an omicron subvariant that is highly transmissible, said Dr. Richard Seidman, chief medical officer for L.A. Care, a public Medicaid insurance plan that serves county residents. The number of covid cases and hospitalizations had been declining since February, but the county is again seeing a bump in cases, according to data released this week.

People have various reasons for remaining unvaccinated, Seidman said. “For some, it’s distrust of the government or health care providers in general,” he said. “Some are more cautious and want to take a wait-and-see approach. Others simply don’t believe the science.”

A study published April 11 by JAMA Internal Medicine shows just how entrenched views are. Many people who refused to get vaccinated early on said they were waiting for the shots to get full approval from the FDA. But when the agency’s first full approval of a covid vaccine came in August 2021, the study concluded, it did little to change people’s minds and “had little immediate impact on vaccination intentions.”

In California, unvaccinated people were nearly 14 times as likely to die from covid as people who had been fully vaccinated and received a booster dose, according to state data from March 7-13.

Perez said people getting their first shots now are doing so mainly because they feel obligated — to meet a work requirement, for example, or enter places such as restaurants, bars, and gyms that require proof of vaccination.

That was the case for Modesto Araizas, one of the two people who showed up at the Palmdale vaccine event. Despite contracting covid twice, missing work, and having a hard time breathing, he didn’t get vaccinated until he needed proof of vaccination to eat at his favorite seafood restaurant.

“I haven’t been scared,” said Araizas, 46. “I take vitamins, eat healthy food, and I work out.”

Until recently, the federal government reimbursed doctors, hospitals, and other providers for tests, treatments, and vaccines for uninsured people. But the Health Resources and Services Administration stopped accepting reimbursement claims for tests and treatments March 22, and for vaccinations April 5.

Many uninsured people now will likely need to pay out-of-pocket for tests and other services.

Perez is hoping people might become more open to vaccines if covid tests become too expensive for them. No one will want to keep paying for tests when they can just get a shot, he reasoned.

Nurse Roxanna Segovia works at a pop-up vaccine and testing clinic in front of South LA Cafe in South Central LA. She recently spent 45 minutes trying to persuade a man who had visited the clinic regularly for free tests to get vaccinated.

“He gave me all the reasons he has not been vaccinated, like his civil rights were being violated and Bible verses,” Segovia said. “His job requires it now, and he said he was losing money by missing work waiting for test results. If he continued this way, he wouldn’t be able to feed his family, but even so, he still wasn’t sure if he was making the right choice.”

At the end of their conversation, he got the shot.

This story was produced by KHN, which publishes California Healthline, an editorially independent service of the California Health Care Foundation.




Kaiser Health NewsThis article was reprinted from khn.org with permission from the Henry J. Kaiser Family Foundation. Kaiser Health News, an editorially independent news service, is a program of the Kaiser Family Foundation, a nonpartisan health care policy research organization unaffiliated with Kaiser Permanente.

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Resurging COVID-19 events related to cold-chain food or packaging contamination

Study: Time course and epidemiological features of COVID-19 resurgence due to cold-chain food or packaging contamination. Image Credit: Sorn340 Studio Images/Shutterstock

In a recent study published in the latest issue of the Biomedical Journal, researchers reviewed coronavirus disease 2019 (COVID-19) resurgence events in China related to frozen food and packaging contaminated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Study: Time course and epidemiological features of COVID-19 resurgence due to cold-chain food or packaging contamination. Image Credit: Sorn340 Studio Images/Shutterstock
Study: Time course and epidemiological features of COVID-19 resurgence due to cold-chain food or packaging contamination. Image Credit: Sorn340 Studio Images/Shutterstock

They identified one of the weak links of the SARS-CoV-2 epidemic where patient zero often remained hidden and was hard to detect, such that the infectious disease outbreak was apparent only after a while and by that time had spread uncontrollably. The current review findings could help devise more effective COVID-19 mitigation and intervention strategies for the future.

Background

After the first COVID-19 outbreak of late 2019 in Wuhan, China, several incidences of COVID-19 resurgence events related to frozen food or packaging contamination have been reported as China imports frozen food from countries where the COVID-19 epidemic is ongoing.

Most of these events reported since July 2020 traced back to frozen shrimp imported from Ecuador. Later, in September 2020, the live SARS-CoV-2 virus was isolated from the outer packaging of imported frozen cod carried by the two stevedores found to be SARS-CoV-2-positive during a routine nucleic acid amplification test (NAAT) testing of the personnel in Qingdao Port, China. According to the authors, this event is the first known case where live SARS-CoV-2 was detected on cold-chain food in the world, confirming that it can survive on cold-chain food packaging and spread through cross-border transportation.

Perhaps SARS-CoV-2 itself is not responsible for the material surface contamination. In lieu, the enclosed and highly humid environment of food packaging and processing facilities and transportation favors the material-to-human SARS-CoV-2 spread. To date, epidemiological features of such COVID-19 outbreaks and the risk of this transmission route remain unclear.

In the present study, researchers conducted a literature search on the official website of the Centers for Disease Control of China and local authorities to identify COVID-19 resurgence events related to cold-chain food or packaging contamination. Additionally, they gathered the relevant epidemiological events and laboratory evidence to support their work.

Incidences of COVID-19 resurgence in China

On August 6th, 2020, in Yingkou, Liaoning Province, China, three packaged food samples were SARS-CoV-2-positive, whereas all 43 employees and 306 personnel of the enterprise tested SARS-CoV-2-negative in the NAAT and antibody tests. This finding led researchers to one of the most intriguing findings of this literature review that SARS-CoV-2 does not transmit via eating or buying cold-chain food products. Thus, it is evident that only the port staff, especially the stevedores, were at high risk of contracting SARS-CoV-2 as they came in direct contact with virus-contaminated materials and needed COVID-19 vaccination on priority.

Further, this finding led to the understanding that successful COVID-19 transmission to humans occurs through the material surface only when – i) a human (host) comes in direct contact with the SARS-CoV-2-contaminated material surface, including food packaging and ii) the human carrier sheds the virus to the surface.

Interestingly, SARS-CoV-2 stays viable (live) and stable on material surfaces, such as cardboard and plastic, for days, particularly under refrigerated (4°C) and frozen (-10 to -80°C) conditions; however, when it finds another human body through direct contact, it rapidly disseminates via human-to-human transmission.

Incidences of COVID-19 resurge in other countries

A rather popular COVID-19 resurgence event occurred in Auckland, New Zealand in August 2020. After 102 consecutive days of zero local cases of COVID-19 in Auckland, authorities reported four lab-confirmed COVID-19 cases in one Auckland household with no overseas travel history. Notably, one of the SARS-CoV-2-positive individuals in this household worked with a cold-chain company.

Within two days, three more employees tested SARS-CoV-2-positive, and seven family members of these cold-chain workers also tested positive. By October 2020, there were 179 origin-unknown cases with a C.12 lineage of SARS-CoV-2, designated as the outbreak of Auckland August Cluster.

Likewise, similar outbreaks have occurred in several other countries, including Australia, Japan, Germany, and the United States, among workers of food processing facilities.

Additionally, there have been multiple cruise ship outbreaks of norovirus in the United States between July and October 2019. The present food provisioning review traced this infection to imported frozen raspberries from China, which then had to be recalled. Workplace conditions, such as prolonged close contact with coworkers, shared workspace and transportation, and congregate housing, also add to the risk for SARS-CoV-2 infection.

According to the data released by the Centers for Disease Control and Prevention (CDC), United States, between March 1st and May 31st, 2020, there were 28,364 reported cases and 132 deaths among workers in 382 meat and poultry processing facilities in several US states. Often these workplaces were crowded and highly humid, overall, conducive for human-to-human, human-to-material, and material-to-human transmissions.

Conclusions

To conclude, the study highlights the significance of surveying materials and the entire territory where imported products arrive as frequent human testing alone does not suffice. Additionally, the study data suggest that regular sampling and proper disinfection of imported products are effective ways to detect SARS-CoV-2 and prevent its spread on material surfaces.

In 2021, the Joint Prevention and Control Mechanism of the State Council of the People’s Republic of China issued a series of technical guidance for the prevention of COVID-19 transmission related to cold-chain food and controlled occurrence of several community-level outbreaks with the potential to turn into an epidemic.