2019 Novel Coronavirus (SARS-CoV-2, COVID-19)

2019 Novel Coronavirus (SARS-CoV-2, COVID-19)

Last updated: 4/2/2020

Reviewers: Dr. Gary Gonzalez, MD; Dr. Shayna Sandhaus, PhD., Chemistry; Julia Dosik, MPH; and Andrew Roberts Jr., MPH in Global Health

1 Background

Over the last few decades, several new viruses have emerged as threats to human health around the globe. The most recent example is the 2019 novel coronavirus.

The virus itself is called SARS-CoV-2, and the disease it causes is called COVID-19 (short for Coronavirus Disease 2019).

SARS-CoV-2 came to the attention of health authorities in late 2019 when it was identified as the cause of a small number of pneumonia cases in the city of Wuhan in Hubei province, China (WHO 2020). Since then, COVID-19 has spread globally and was declared a pandemic by the World Health Organization on March 11th, 2020 (CDC 2020b; Chappell 2020).

Coronaviruses are a large group of related viruses that cause many common human and animal infections (Li 2020). In humans, coronaviruses typically cause mild respiratory infections. Responsible for an estimated 10–30% of all upper respiratory tract infections, coronaviruses are among the most frequent causes of the common cold (Paules 2020). Over the last decade, new coronaviruses that cause potentially lethal respiratory diseases have emerged. These include severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses (Su 2016).

The SARS pandemic in the early 2000s, which lasted about nine months in 2002–2003, affected over 8,000 people in 29 world regions and caused fatality in almost 10% of cases. MERS, on the other hand, has been smoldering mainly on the Arabian Peninsula since 2012, infecting approximately 2,400 people and having a case fatality rate of nearly 35% (Hui 2020; Killerby 2020). For perspective, the fatality rate of typical influenza viruses is much lower, reaching a maximum of about 0.2% in people over 75 years old; however, because of its high incidence, the number of deaths attributable to the flu worldwide averages between 291,000 and 646,000 annually (Iuliano 2018).

Although the characteristics of COVID-19 illness are still being elucidated, those most likely to contract the disease are people in close proximity to other infected individuals. Importantly, healthcare workers are at increased risk of developing and transmitting coronavirus infections (Judson 2019; Otter 2016).

The most common presentation of COVID-19 is fever and dry cough followed by flu-like symptoms. Some reports indicate that patients may experience ocular symptoms, such as conjunctivitis (pink eye) and eye discharge (Wu 2020b). Emerging evidence suggests that some people may experience gastrointestinal symptoms such as loss of appetite or diarrhea in addition to—or in rare cases instead of—initial respiratory symptoms (Wuhan Medical Treatment Expert Group for COVID-19; Xiao 2020).

Rapid progression to pneumonia and death is more likely to occur in older individuals and those with pre-existing conditions that increase their risk such as obesity, diabetes, or hypertension (Li 2020; Yang 2020; Hui 2020; Azhar 2019). As of mid-March, 2020, commonly reported estimates of the case-fatality rate range from about 1% to 3%; however, the potential for mild cases to go undetected means that the actual fatality rate may be much lower (Wang 2020; Fauci 2020).

NOTE: At the first signs of a respiratory tract infection (e.g., sneezing, coughing, feeling unwell, mild fever), contact your doctor and immediately initiate the interventions described in the Integrative Approaches section of this Protocol. The interventions described in this Protocol, though not necessarily validated as effective specifically for COVID-19, are nevertheless advisable upon onset of symptoms of respiratory tract infections.

2 Spread

Coronaviruses are highly adaptable and known to undergo host-switching. Several established human coronaviruses have evolved from bird or mammalian coronavirus origins (Corman 2018). For example, the human coronavirus associated with MERS is likely to have come from camels, though its origins may have been a bat coronavirus; the SARS coronavirus also appears to have originated in bats and was possibly transmitted by an intermediate mammalian host called a civet (Azhar 2019; Hui 2019). Although distinct from all other known coronaviruses, SARS-CoV-2 also appears to be closely related to a bat coronavirus (Chen 2020).

Once adapted to the human host, coronaviruses can become transmissible between humans. There are four possible routes of transmission: respiratory droplet, contact, aerosol, and oral-fecal (Shiu 2019).

  • Respiratory droplet. Respiratory droplets are thought to be the most important source of SARS-CoV-2 transmission. In this kind of viral transmission, the virus is suspended in droplets emitted from the respiratory tract of an infected individual through a sneeze or cough, which are then inhaled by nearby uninfected individuals. Another possibility is that droplets may land on or near uninfected individuals, be picked up on hands, and transferred to the respiratory tract through touching the nose, mouth, or eyes (Hui 2019). Because respiratory droplets play such an important role in transmission of SARS-CoV-2, it is imperative that everyone practices social distancing whenever possible.
  • Contact. Direct person-to-person contact is another mode of transmission for coronaviruses such as those associated with SARS, MERS, and the current COVID-19 outbreak (Killerby 2020). In these cases, the virus is transferred when an uninfected individual comes into direct contact with an infected person who is actively shedding virus.
  • Aerosol. The aerosol route of transmission involves inhalation of airborne viruses, possibly at some distance from the infected person (Judson 2019; La Rosa 2013). Aerosol transmission appears to be an especially important concern in healthcare settings (Judson 2019). SARS-CoV-2 aerosols are detectable for up to three hours (Kampf 2020).
  • Oral-fecal. The oral-fecal route involves viruses being shed through the feces (usually in people with diarrhea), contaminating surfaces and ultimately hands that can then introduce the virus to the respiratory tract. This is an uncommon but documented route of transmission for coronaviruses such as the SARS virus (Hui 2019).

3 Protective Measures

Below are some basic measures to consider in order to reduce your risk of contracting COVID-19 and other viral illnesses.

  1. Social distancing. Avoiding contact with infected individuals is the most effective strategy to protect yourself from COVID-19. Because SARS-CoV-2 has become pervasive throughout the world, you should assume the people you come in contact with may be infected and stay at least six feet away from them. The CDC and other health authorities worldwide strongly advise that citizens—especially those at increased risk—living in communities experiencing community spread of COVID-19 "[remain] out of congregate settings, avoid mass gatherings, and maintain distance (approximately 6 feet or 2 meters) from others when possible" (CDC 2020d). In some places where the virus has become more widespread, more stringent measures have been taken such as closing public parks, limiting activity outside the home to "essential" tasks, and urging people to remain at home as much as possible. Such strict measures can help further limit the spread of infection.

  2. Avoid non-essential travel. Avoiding travel to areas with known community spread is advisable (CDC 2020c). In addition, all air travel is associated with exposure to people and the infectious agents they carry. Outbreaks of infectious illnesses, including measles, influenza, SARS, and many others, aboard commercial flights have been documented (Mangili 2015; Hertzberg 2016). Therefore, avoiding air travel is a reasonable precaution for reducing your risk of viral infections in general, particularly if you have other vulnerabilities.

  3. Wash your hands. Frequent hand washing is an important strategy for protecting against all types of infectious diseases. Studies in office and healthcare settings have further demonstrated strategic use of alcohol-based surface disinfectants and hand sanitizers can reduce viral spread by 85–94% (Kurgat 2019; Reynolds 2019).

  4. Strengthen immunity. Optimal functioning of the immune system is vital for defending against all types of infections, from mild colds to dangerous influenza and life-threatening pneumonia. A nutrient-dense diet, regular exercise, adequate sleep, and stress management can all contribute to healthy immune function (Zapatera 2015). Other strategies for strengthening immunity and reducing risk of viral infections can be found in Life Extension’s Influenza, Pneumonia, and Immune Senescence protocols.

  5. Disinfect surfaces. A study published on March 17th, 2020 by scientists from the U. S. National Institutes of Health and CDC along with UCLA and Princeton University researchers found that SARS-CoV-2 aerosols were detectable for up to three hours. The virus was detectable on cardboard for up to 24 hours and for up to three days on plastic and stainless steel (van Doremalen 2020).

    Fortunately, coronaviruses can be inactivated with proper cleaning and disinfecting agents. Therefore, keeping surfaces clean and properly disinfected is important to limit the spread of infectious diseases caused by coronaviruses. A study published on February 6th, 2020 found that coronaviruses on inanimate surfaces can be inactivated within one minute through disinfection with 62%‒71% ethanol, 0.5% hydrogen peroxide, or 0.1% sodium hypochlorite (eg, bleach) (Kampf 2020).

    As of March 6th, 2020, the United States Environmental Protection Agency (EPA) provides a list of EPA-registered disinfectant products for use against the SARS-CoV-2 virus (EPA 2020). The list is available on the EPA’s web page, here: https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov-2.

Should You Wear A Facemask?

Early in the pandemic, officials in the United States and elsewhere discouraged the use of facemasks except by sick individuals and healthcare workers. However, this narrative began to shift in late March and early April, with more experts calling for increased mask wearing by the general public.

A major driving force behind the shift in narrative was an analysis published on March 26th by Lydia Bourouiba, PhD, of the MIT Fluid Dynamics of Disease Transmission Laboratory (Bourouiba 2020). Whereas social distancing guidelines have called for maintaining at least 6 feet (2 meters) between individuals, Dr. Bourouiba’s analysis concluded that gaseous ejecta from human sneezes can travel up to 23 to 27 feet. The conclusion is that current social distancing guidelines may be insufficient to protect healthy individuals from becoming infected by sick individuals. Facemasks may be able to mitigate the forward momentum of potentially infectious ejecta and possibly reduce disease transmission. Another potential benefit is that facemasks could reduce the transmission of disease by infected but asymptomatic individuals (Feng 2020; Jefferson 2011).

Local governments of some large municipalities in the United States began calling for widespread facemask wearing in early April. For instance, Los Angeles Mayor Eric Garcetti recommended on April 2nd that all residents wear facemasks when in public (Wise 2020). The World Health Organization is also reportedly re-evaluating their recommendations, but still does not recommend widespread mask wearing as of April 2nd (Shukman 2020).

As of early April, it may be prudent for vulnerable populations such as the elderly and those with conditions that increase their risk to wear masks in public even if they are not sick. Guidelines and recommendations for facemask usage will evolve as more evidence emerges.

Because facemasks remain crucial for healthcare workers, it is imperative that the general public avoid hoarding masks, even if general recommendations begin to lean more heavily in favor of large-scale mask wearing (Blanco 2016).

4 Know the Facts Video

Our Director of Education Dr. Michael Smith debunks common misperceptions about COVID-19 and offers guidance for staying well.

5 Testing and Diagnosis

Testing for COVID-19 has been inefficiently rolled out in the United States and many other countries. As of March 31st, 2020, there are two testing priorities that both the public and private sectors are working to optimize in the United States:

  1. establish widespread availability of accurate, rapid point-of-care diagnostic tests for COVID-19, and
  2. establish widespread and accurate serological (blood serum) tests to determine who has been exposed and subsequently recovered, establishing immunity.

As of March 31st, testing capacity in the United States was insufficient to test all potentially infected individuals and to engage in population screening. Therefore, testing has been prioritized for hospitalized patients, the highly vulnerable, healthcare workers, and first responders. The decision to order a test has been left up to individual clinicians and their clinical judgement. In late March, the CDC updated their testing priority guidelines as follows (CDC 2020a):

Priority 1

  •     Hospitalized patients
  •     Symptomatic healthcare workers

Priority 2

  •     Patients in long-term care facilities with symptoms
  •     Patients 65 years of age and older with symptoms
  •     Patients with underlying conditions with symptoms
  •     First responders with symptoms

Priority 3

  • Critical infrastructure workers with symptoms
  • Individuals who do not meet any of the above categories with symptoms
  • Healthcare workers and first responders
  • Individuals with mild symptoms in communities experiencing high COVID-19 hospitalizations

Non-Priority

  • Individuals without symptoms

If you have symptoms such as fever, dry cough, fatigue, lack of appetite, and muscle pain and think you might have COVID-19, but do not have urgent symptoms such as shortness of breath, you should call your doctor or your local health department for further guidance. Do not go to the doctor’s office or the hospital for testing unless you feel your condition is severe and/or your condition is rapidly worsening. Because there is no effective treatment for COVID-19 at present and interacting with other people risks transmitting the infection, people with mild symptoms should rest at home. 

Unfortunately, there is a lot of misinformation circulating as to the availability of testing in the United States. As of March 31st, there are no FDA-approved at-home tests, and you cannot have your test performed at laboratory patient service centers (such as your local LabCorp or Quest facility). The tests that are available and validated have to be ordered by a doctor, and a clinician has to collect the sample to be sent to a qualified lab for analysis. Results may take several days, depending on the testing methodology. Over the coming several weeks, accurate, rapid testing may become more widely available and testing guidance will likely expand to include larger portions of the population.

6 Medications

Because there are no proven medical treatments for COVID-19 or other human coronaviruses, scientists are looking to both old and new antiviral drugs in search of effective therapies. Several drugs are currently being evaluated in preliminary research. These include antiviral drugs used to treat human immunodeficiency virus (HIV) and hepatitis B and C, such as ribavirin (Ribasphere), lopinavir-ritonavir (Kaletra), and interferon beta-1b (Betaseron) (Sheahan 2020; Chu 2004; Dyall 2017). An early-stage, open-label clinical trial published in the New England Journal of Medicine on March 18th, 2020, failed to show benefit with lopinavir-ritonavir in patients with severe COVID-19 (Cao 2020).

The antimalarial drug chloroquine (Aralen) has shown broad-spectrum antiviral effects in preclinical research, indicating its potential role in combined-drug approaches to treating emerging coronavirus infections (Dyall 2017). Preliminary evidence from multi-center clinical trials conducted in China suggest chloroquine phosphate has clinical efficacy against COVID-19 (Gao 2020). However, its use remains investigational until more rigorous clinical trials can be completed (Cortegiani 2020). Hydroxychloroquine, a less-toxic derivative of chloroquine (McChesney 1983), has been shown in preliminary studies to be efficacious against SARS-CoV-2. Several trials are currently underway to assess the clinical utility of hydroxychloroquine in COVID-19 patients (Frieden 2020; Lecrubier 2020; Liu 2020a).

Remdesivir is another antiviral drug that has shown promise against SARS-CoV-2 in preliminary pre-clinical studies. It is a prodrug of an adenosine analog that has potent antiviral activity against many RNA virus families (Agostini 2018). A 2018 in vitro study showed that remdesivir was efficacious against two strains of human endemic coronavirus (HCoV-OC43 and HCoV-229E) (Brown 2019). A drug screening study published on February 4th, 2020 showed remdesivir and chloroquine were both effective at inhibiting SARS-CoV-2 in vitro (Wang 2020). The Wall Street Journal published an article on January 31st indicating that the pharmaceutical company Gilead has entered into agreement with Chinese health authorities to conduct priority clinical trials to assess the efficacy of remdesivir in patients infected with SARS-CoV-2 (Walker 2020).

On Feb. 25th, 2020, the U. S. National Institutes of Health (NIH) announced the commencement of the first clinical trial of remdesivir for COVID-19 in the United States. The trial is taking place at the University of Nebraska Medical Center in Omaha. This trial will help establish whether remdesivir can offer robust clinical benefits for COVID-19 patients (NIH 2020).

The utility of glucocorticoids for treating acute respiratory distress syndrome (ARDS) has been debated for some time (Hough 2014). Whether glucocorticoids are helpful in patients with ARDS depends on the severity and underling cause of ARDS. In the context of MERS, some evidence suggested that glucocorticoid use was associated with greater mortality (Alfaraj 2019). However, a study published March 13th, 2020 in JAMA suggested corticosteroid use (methylprednisolone) was associated with lower mortality in Chinese COVID-19 patients with ARDS (Wu 2020a). As of March 16th, 2020, several randomized controlled trials are planned to assess the efficacy of glucocorticoids in COVID-19 patients (ClinicalTrials.gov 2020). Until more definitive evidence can be derived from these trials, the decision to use glucocorticoids should be made by the treating physician.

In the face of low efficacy and challenging adverse side effects of known medications, researchers are searching for new approaches. Immunotherapy using monoclonal antibodies could have a role in treating MERS, SARS, and other emerging coronavirus infections such as COVID-19 (Jin 2017), and novel compounds with anti-coronavirus activity are currently being developed and tested (Sheahan 2017).

Angiotensin-II Receptor Blockers (ARBs), ACE inhibitors, and COVID-19

The SARS-CoV-2 virus enters the human body by interacting with a receptor on the outside surface of cells called angiotensin converting enzyme 2 (ACE2). ACE2 is a component of the renin-angiotensin system, which plays a critical role in maintaining homeostasis. Popular blood pressure medications—angiotensin converting enzymes inhibitors (ACE inhibitors [ACEi]) and angiotensin II receptor blockers (ARBs)—modulate this system to control blood pressure. Examples of ACEis are lisinopril (Prinivil, Zestril) and enalapril (Vasotec); ARBs include losartan (Cozaar) and telmisartan (Micardis).

When it became widely reported that ACE2 served as the receptor site for SARS-CoV-2, many people taking ACEis or ARBs grew concerned that these drugs could increase their risk of COVID-19. However, cardiology societies around the world have issued statements urging patients not to discontinue their blood pressure medications, and stating that there is no compelling evidence that these drugs increase risk of COVID-19 (HFSA/ACC/AHA 2020; Patel 2020). It is important to keep in mind that stopping a blood pressure medication does have known risks and is not advised.

Emerging, preliminary evidence suggests ARBs may actually be linked with improved outcomes in COVID-19. While it is crucial to acknowledge that these findings are preliminary, a retrospective study presented (pre-peer review) in late March suggested that people who had been taking ARBs prior to developing COVID-19 were less likely to develop severe disease than people who had not been taking ARBs (Liu 2020b). Other preclinical and preliminary evidence supports the potential beneficial effects of ARBs in COVID-19 as well (Cheng 2020). Ongoing clinical trials will help clarify the role of ARBs in COVID-19; results of some of which are expected in April 2020 (Tignanelli 2020a; Tignanelli 2020b).

 

NSAIDs (eg, Ibuprofen) and COVID-19

In mid-March, questions arose as to whether non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen would be helpful or harmful in the context of COVID-19. As of March 19th, 2020, most experts agreed that evidence was too limited to make a conclusive recommendation for or against NSAIDs, but that there was little evidence that NSAIDs would worsen outcomes in most cases (Melville 2020; NY Daily News 2020). Nevertheless, some physicians and health authorities recommended acetaminophen (Tylenol, known as paracetamol in Europe) rather than ibuprofen or other NSAIDs in the context of COVID-19.

The concern with NSAIDs in the context of COVID-19 is that the drugs may mask the early symptoms of COVID-19, or possibly suppress the immune response to the virus, worsening outcomes. However, these concerns remain theoretical as of March 19th, 2020. As of this writing, there is no evidence that taking NSAIDs increases risk of infection with SARS-CoV-2 or of developing COVID-19 (Melville 2020).

7 Integrative Approaches

There are many integrative therapies with well-established antiviral and immune-modulating properties. Details regarding these therapies can be found in Life Extension’s Influenza, Pneumonia, and Immune Senescence protocols. The interventions described in these protocols, though not necessarily validated as effective specifically for COVID-19, are nevertheless advisable upon onset of symptoms of upper respiratory tract infections.

For upper respiratory tract infections in general, including those caused by some types of coronaviruses, Life Extension has long recommended swift action to help bolster your immune response and mitigate the likelihood of a severe disease course. At the first signs of an upper respiratory tract infection (eg, sneezing, coughing, feeling unwell, mild fever), make an appointment with your doctor then take the following:

  1. Zinc Lozenges : Completely dissolve in mouth one lozenge containing 18.75 mg of zinc acetate every two waking hours. Do not exceed 8 lozenges daily, and do not use for more than three consecutive days.
  2. Garlic: Take 9,000‒18,000 mg of a high-allicin garlic supplement each day until symptoms subside. Take with food to minimize stomach irritation.
  3. Vitamin D: If you do not already maintain a blood level of 25-hydroxyvitamin D over 50 ng/mL, then take 50,000 IU of vitamin D the first day and continue for three more days and slowly reduce the dose to around 5,000 IU of vitamin D each day. If you already take around 5,000 IU of vitamin D every day, then you probably do not need to increase your intake.
  4. Cimetidine: Take 800‒1,200 mg a day in divided doses. Cimetidine is a heartburn drug that has potent immune enhancing properties. (It is sold in pharmacies over-the-counter.)
  5. Melatonin: 3‒50 mg at bedtime.

Do not delay implementing the above regimen. Once viruses that cause respiratory infections infect too many cells, they replicate out of control and strategies like zinc lozenges will not be effective. Treatment must be initiated as soon as symptoms manifest. Although this regimen has not been studied specifically in the context of COVID-19, there is little reason not to implement this strategy along with contacting a qualified healthcare provider as soon as possible after onset of upper respiratory tract infection symptoms.

Below are a few additional integrative interventions that have shown beneficial immune-enhancing effects in the context of viral upper respiratory tract infections.

  • Vitamin C. Several studies have shown that vitamin C supplementation, both before and soon after the onset of symptoms of upper respiratory tract infections, may help ease symptom burden and reduce the duration of illness (Gorton 1999; Hemilä 1999; Ran 2018). However, the available evidence does not consistently support the notion that preventive vitamin C supplementation can reduce the risk of acquiring upper respiratory tract infections (Hemilä 2013; Virilhon 2019). Importantly, studies to date have not focused specifically on coronavirus infections but on upper respiratory tract infections in general such as those caused by rhinoviruses, enteroviruses, and influenza viruses.
     
    As of March 4th, 2020, a study is slated to take place in Wuhan, China to test the effects of twice-daily 12-gram intravenous vitamin C infusions on outcomes in COVID-19 patients. The primary outcome will assess ventilation-free days, and one of several secondary outcomes will be 28-day mortality (Peng 2020). Previously, a 2017 case report suggested that high-dose intravenous vitamin C may have contributed to the recovery of a 20-year-old patient with acute respiratory distress syndrome (ARDS) due to a viral respiratory tract infection (Fowler 2017). On April 1st, 2020, the American Association of Naturopathic Physicians issued a recommendation in favor of the use of intravenous vitamin C as supportive care for patients with COVID-19. Their recommended dosing regimen is 100 mg/kg as a 24-hour continuous infusion for general supportive care, and 200 mg/kg (24-hour continuous infusion) for patients thought to be experiencing a profound inflammatory immune response known as “cytokine storm” (AANP 2020).
  • N-acetylcysteine (NAC). N-acetylcysteine (NAC) is an amino acid derivative with mucolytic properties often used in the context of respiratory illnesses (Blasi 2016; Kalyuzhin 2018; Samuni 2013). A meta-analysis published in 2017 found that treatment with NAC led to shorter duration of intensive care unit (ICU) stay compared with control among patients with ARDS (Zhang 2017). In the current COVID-19 pandemic, some Chinese institutions have been using NAC as part of the standard management of patients in the hospital setting (Wu 2020a), although clinical trials are needed to specifically assess outcomes in COVID-19 patients treated with NAC. Some researchers have suggested NAC could be a valuable therapeutic in COVID-19 on the basis of its potent antioxidant and mucolytic properties (McCarty 2020).
  • Lactoferrin. Lactoferrin is a glycoprotein involved in immune response and several other functions (Baveye 1999). It is found in secreted fluids and is abundant in milk (breast and cow). Lactoferrin has well-documented antibacterial, antiviral, and antifungal properties (Malaczewska 2019; Wakabayashi 2014; Ishikawa 2013). It appears to exert antiviral effects by activating the antiviral cytokines interferon (IFN)-α/β and boosting natural killer (NK) cell activity and Th1 cytokine responses (Wakabayashi 2014). Some studies suggest that lactoferrin administration may reduce the incidence and severity of common respiratory tract viral infections, like colds and flu (Vitetta 2013; Wakabayashi 2014).
     
    In 2005, researchers reported that the gene encoding lactoferrin was highly upregulated in patients affected during the SARS epidemic that emerged in 2003, suggesting that it plays a role in the innate immune response to the infection (Reghunathan 2005). A follow-up study indicated that lactoferrin prevented the 2003 SARS coronavirus from entering host cells (Lang 2011). No data have been published as of March 10th, 2020 directly linking lactoferrin with outcomes in COVID-19 patients.
  • Selenium. Selenium has important antioxidant, anti-inflammatory, and antiviral activities in the body, and deficiency is associated with increased risk of viral infection (Wrobel 2016). In patients with HIV infection, poor selenium status is correlated with increased mortality, and supplementation has been reported to slow progression of immune dysfunction and reduce hospital admissions (Wrobel 2016; Muzembo 2019). Some researchers have proposed that lack of selenium in regional soils may have contributed to the SARS outbreak in 2003 (Harthill 2011).
  • Probiotics. A growing body of evidence shows probiotic supplements with Bifidobacterium and Lactobacillus species can enhance antiviral immune activity and may reduce the occurrence, severity, and duration of viral respiratory tract infections such as influenza (Lenoir-Wijnkoop 2019; Mousa 2017).
  • Epigallocatechin gallate (EGCG). EGCG is a polyphenol from green tea. Because of its broad antiviral effects, EGCG has been proposed as a promising agent for preventing and treating viral infections such as SARS and MERS (Kaihatsu 2018; Hsu 2015).

8 Obtaining Reliable Situation Updates

The CDC regularly updates their COVID-19 information portal. This is a reliable and trustworthy source of information about SARS-CoV-2 and COVID-19. The URL is: https://www.cdc.gov/coronavirus/2019-ncov/summary.html

Disclaimer and Safety Information

This information (and any accompanying material) is not intended to replace the attention or advice of a physician or other qualified health care professional. Anyone who wishes to embark on any dietary, drug, exercise, or other lifestyle change intended to prevent or treat a specific disease or condition should first consult with and seek clearance from a physician or other qualified health care professional. Pregnant women in particular should seek the advice of a physician before using any protocol listed on this website. The protocols described on this website are for adults only, unless otherwise specified. Product labels may contain important safety information and the most recent product information provided by the product manufacturers should be carefully reviewed prior to use to verify the dose, administration, and contraindications. National, state, and local laws may vary regarding the use and application of many of the therapies discussed. The reader assumes the risk of any injuries. The authors and publishers, their affiliates and assigns are not liable for any injury and/or damage to persons arising from this protocol and expressly disclaim responsibility for any adverse effects resulting from the use of the information contained herein.

The protocols raise many issues that are subject to change as new data emerge. None of our suggested protocol regimens can guarantee health benefits. Life Extension has not performed independent verification of the data contained in the referenced materials, and expressly disclaims responsibility for any error in the literature.

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