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Expert comment on antibody tests for COVID-19

What do we know about the immune response to COVID-19 and how does this differ by age, gender, co-morbidities or other traits? What are the different tests available? How reliable are they? Do the tests show immunity? And do we even know how long immunity to COVID-19 might last.

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By Professor Georgina Ellison-Hughes, Dr Rocio Martinez-Nunez and Dr Rui Ribeiro Galao
Faculty of Life Sciences & Medicine
King’s College London

With promises of antibody tests being rolled out in the next few days, and retailers told not to send home-testing kits as their accuracy is questioned, it is timely to consider what we do and don’t know about these tests. What do we know about the immune response to COVID-19 and how does this differ by age, gender, co-morbidities or other traits? What are the different tests available?  How reliable are they? Do the tests show immunity? And do we even know how long immunity to COVID-19 might last.

What do we know about the immune response to COVID-19?

The immune response to COVID19 can be split into a healthy antiviral immune response or a defective/overactive immune response, which is often implicated in the resulting damage to the lungs and other organs, and then the person can be severely ill. There is a high percentage of patients that get infected with SARS-CoV-2 and do not develop any symptoms, hence the importance of social distancing to protect others since we do not know who can be carrying the virus.

Initially, viral infection switches on antiviral defences. These include interferons and pro-inflammatory cytokines and chemokines, which kill the virus and attract immune cells (neutrophils, monocytes, macrophages and T cells) to the site of infection. The virus enters cells employing ACE2 as a receptor, a protein that is expressed in many cell types and present in the epithelium in the airways.

In the healthy immune response, the innate antiviral defences fight against the virus and virus-specific T cells can later eliminate the infected cells before the virus spreads. Neutralizing antibodies in these individuals can block viral infection, and phagocytic cells such as alveolar macrophages recognize neutralized viruses and apoptotic cells and clear them by phagocytosis. Altogether, these processes lead to clearance of the virus and minimal lung damage, resulting in recovery.

In a defective immune response, there is a hyperactivation of the immune cells in the lungs causing overproduction of pro-inflammatory cytokines (cytokine storm), which eventually damages the lungs. The resulting cytokine storm circulates to other organs, leading to multiple organ damage. 

In patients that are severely ill there is a combination of multi-organ damage, increased coagulation and lymphopenia. Researchers are trying to elucidate the mechanisms underlying these responses and the causes for the hyperactivation of the immune response.

Longer-term immunity is acquired through antibodies made by the B cells of the immune system, which stick around in the blood post-infection. These antibodies can bind to the virus, either neutralizing it directly or marking it for destruction by other immune cells. Studies have found high levels of neutralizing antibodies to SARS-CoV-2 in recently recovered patients. This is the principle behind new trials such as those at Guy’s and St Thomas’ Hospitals in which severely ill patients receive plasma from recovered donors. Memory T cells are another source of long lasting immunity and are generated when a person gets infected, remaining in the blood and responding rapidly when re-infection occurs.

How does the immune response differ by age, gender, co-morbidities and other traits?

As we have observed, everyone responds differently to the virus with most healthy, infected people under the age of 65 making a full recovery. However, there is increased severity with age, and if you have an underlying health condition i.e. cardiovascular disease or diabetes. Black and ethnic minorities also seem more affected.

A retrospective, multicentre cohort study has shown old age, being male and cardiovascular disease co-morbidity are risk factors for mortality of COVID19 (Zhou et al. 2020, The Lancet). The most common cardiovascular co-morbidity as a risk factor for mortality is hypertension, followed by diabetes. Moreover, prevalence of hypertension is highest in the elderly population and advanced age remains the strongest predictor of COVID-19 related death.

Because disease severity is due to not only the viral infection but also the host response, older individuals suffer because they have a progressive decline in immune function with increasing age, called immunosenescence.

Another risk factor to disease severity and dying from COVID19 is being male. The reasons for this are currently unclear, but it has been suggested that women may naturally have stronger immune defences than men. Another possibility is that comorbidities associated with poorer prognosis are more common in men.

What are the various antibody test being trialled in labs, and being sold to the public? 

With no ‘gold standard’ for antibody testing and an incomplete knowledge of the immunology of COVID-19, it has been problematic to evaluate serologic tests. Several lateral flow immunoassays (similar to a pregnancy test) were initially trialled, with ease of use and affordability weighing heavily in their favour. Several of these have presented high sensitivities and specificities and are available to buy by the public (companies such as Alpha and Blue Horizon). The kits manufactured by Roche and Abbott will shortly be available on the NHS. There is a drive now to test different ELISA platforms including Abbott. ELISA takes longer than lateral flow tests but is quite reliable and is the preferred option for large scale testing.

What are the different ways you administer these tests? 

These are all blood tests, and most of them just use a finger prick of blood. The Roche and Abbott tests must be carried out by a doctor and the blood is sent to a laboratory for evaluation. The most commonly used method is to take a blood sample, spin it down in a centrifuge to obtain the plasma serum content of the blood and analyse the presence of antibodies, including neutralising antibodies. Saliva may be another source for antibodies.

Will the antibody test show that the person is immune? 

The test will detect whether you have the antibodies (immunoglobulins, IgG and IgM) against SARS-CoV-2. However, having antibodies does not automatically mean you are ‘immune’ against SARS-CoV-2. Neutralizing antibodies are more ‘effective’ against SARS-CoV-2 and most commercial tests detect only if there is presence/absence of immunoglobulins (Ig).

How reliable are the various tests?

The reliability can differ depending on what Ig’s are being detected and how long after you perform the test following testing positive for SARS-Cov-2. The antibody tests available are those that detect the presence of IgM and/or IgG and inform about current (likely in the case of IgM) or previous (IgG) infection with SARS-CoV-2. However, to determine presence of SARS-CoV-2, i.e. if a person is ‘infectious’, PCR remains as the gold standard.

Roche and Abbott have said the level of accuracy for its SARS-Cov-2 antibody test is high, and it was able to distinguish the antibodies from those for closely related coronaviruses, which have been known to produce positive results in tests made by other companies.

What are IgM and IgG antibodies and how do they affect the interpretation of the test?

Immunoglobulin M (IgM) antibodies are usually the first antibody produced by the immune system when a pathogen attacks. A positive IgM test indicates that you may have been infected recently (peaking at day 7-10 post-infection) and that your immune system has started responding to the virus.  When IgM is detected you may or may not still be infected.

Immunoglobulin G (IgG) antibodies develop in most patients within 7 to 10 days after symptoms of COVID-19 begin. IgG antibodies remain in the blood after an infection has passed. These antibodies indicate that you may have had COVID-19 in the recent past and have developed antibodies that may protect you from future infection. Therefore, an IgG antibody test is most reliable as a source of information about previous infection. Tests that combine measurement of IgM and IgG, and therefore do not distinguish between the two, cannot guarantee the presence of IgG antibodies, which are the ones that in theory confer longer immunity and remain in the bloodstream to protect from future infections.

How long does immunity last for?

In patients at least 14 days after discharge from hospital, studies show have high levels of antibody which suggests that their immune system is armed against further attack. Because SARS-CoV-2 has only been around for 6 months, how long the immunity lasts for is unclear. However, if SARS-CoV-2 is like other coronaviruses, like 2002’s SARS 1, or 2012 MERS, then immunity could last for several years. We think that we should err on the side caution because a recent study, by the group of Professor Lia van der Hoek from the University of Amsterdam tested 10 male individuals regularly over a time span of 35 years for four types of coronaviruses, which cause the common cold. Results showed an alarmingly short duration of protective immunity with frequent reinfections at 12 months post-infection and a substantial reduction in antibody levels as soon as 6 months post-infection. It is of note that respiratory viruses are not great at triggering long-lasting immunity.

Believing that everyone's perspective is important, Zest Magazine has opted to provide an avenue for these perspectives to be known. care to hear the publication's contributing writers; or better yet, do some contributing yourself by contacting info@zestmag.com.

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Why hustle culture can do more harm than good to your mental health

Despite the fact that hustle culture causes individuals to increase their working hours and reduce the number of hours they have for sleep, it can actually cause people to become a lot less productive, making the entire culture itself extremely counterproductive.

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Anybody with social media will be aware of the hauntingly popular notion of ‘hustle culture’, which refers to people feeling pressured to work tirelessly, without rest, and to be constantly making money and being productive. 

The research team at Private Rehab Clinic Delamere, has stressed that this notion can be extremely toxic and can cause a negative impact on people’s mental health and wellbeing.

Stress

One of the many negative impacts that hustle culture can have on an individuals mental wellbeing is with extreme stress. Stress in the workplace can affect people both mentally and physically, it can generate feelings of anxiety and cause depression. In phsycial form, stress can cause heart disease, difficulty breathing, headaches and alcohol and drug dependency. 

Stress caused by heavy work pressures, long hours and workloads can result in burnout. Being burnout can affect everyday tasks at work or in the home, it can make an individual feel less productive and it increase the risk of mistakes. In industries that deal with machinery or are based in dangerous environments, this could have catastrophic consequences. 

Anxiety 

Hustle culture creates a toxic environment for fear, guilt and shame, and the glorification of overworking can lead to severe cases of anxiety. The anxiety makes employees feel that they have failed if they ever take a break. Not allowing yourself any time to relax can be extremely dangerous for your mental health and wellbeing. Anxiety can lead to a plethora of other issues including lack of sleep, fatigue, and exhaustion.

Exhaustion

Working too much, feeling constantly under pressure and having a poor sleep cycle can cause exhaustion. This can lead to counter-productivity later down the line as exhaustion can cause difficulty with concentration, memory and even emotional imbalance. 

There are also instances where the body is able to just shut itself down and fall asleep whilst working, this can be extremely dangerous if a person’s industry involves driving vehicles or operating heavy machinery. 

Fatigue

Fatigue is sometimes compared to exhaustion, however fatigue can be more long term and can cause further damage to a person’s mental health and wellbeing. Symptoms can be much more severe than exhaustion too, individuals will often experience headaches, dizziness and muscle pains and weakness.

Fortunately, with some simple and practical lifestyle changes such as taking more breaks and getting proper sleep, fatigue can reduce over time, but in some cases you may need to see a doctor. 

Decreased Productivity 

Despite the fact that hustle culture causes individuals to increase their working hours and reduce the number of hours they have for sleep, it can actually cause people to become a lot less productive, making the entire culture itself extremely counterproductive. 

This is why hustle culture has a negative impact on both employers and employees, for employers they end up with workers being much less productive and the workers themselves begin to face a plethora of physical and mental health issues that can be entirely avoided.

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5 Affordable and simple ways everyone can be an eco warrior

Understanding that collective effort is the way to go, retail giant SM Supermalls is committed to helping all Filipinos make more environmentally friendly choices in every aspect of their life.

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From changing weather patterns to disease outbreaks, we are already feeling the effects of global warming. We need to act now and work together in protecting the planet.

Understanding that collective effort is the way to go, retail giant SM Supermalls is committed to helping all Filipinos make more environmentally friendly choices in every aspect of their life.

“Many people care about the planet but find it hard to create a green lifestyle because of limited time or budget. That’s why we have community programs that make it more convenient and affordable to be an eco-warrior,” says Jonjon San Agustin, SVP for Marketing, SM Supermalls.

Here are five easy ways on how you and your family can live greener.

Segregate your trash and Trash to Cash

Segregating your biodegradable and recyclable waste reduces the amount of trash that goes into landfills. Have separate containers for different kinds of trash: biodegradable for food and garden waste; recyclable for plastic, paper, and metal waste; residual waste for trash that can’t be recycled including used tissue or paper plates; electronic waste for old batteries or broken gadget which shouldn’t be mixed with other waste because they contain metals that can contaminate the soil.

You can bring your recyclable waste to SM Supermalls’ Trash to Cash Recycling Market, held 10 am to 2 pm on every first Friday and Saturday of the Month. Visit this link to find the kiosk locations near you.

Limit the use of plastic through Plastic Waste Collection

Did you know that it takes plastic over 1,000 years to decompose?

About 10% of plastic materials will end up in the ocean and can kill marine life. In the Philippines, plastic waste often congests sewage systems causing floods. You can avoid using single use plastic by bringing your own reusable containers or eco bags when going to the groceries.

You can also buy items in eco-friendly packaging.

Plastic cutlery and straws are optional during order delivery or takeout. For dine-in, you can have your own eco-kit which has a drinking bottle, a set of utensils, and a foldable eco bag. Go green anytime and anywhere!

You can also recycle your plastic waste through SM Supermalls’ Plastic Waste Collection programs. Make it a fun weekend and volunteer for SM by the Bay and SM Mall of Asia’s regular ocean clean-up drives.

Plant a garden

Plants help stop climate change by removing carbon dioxide from the air. If you don’t have a large yard for a garden, you can still get houseplants! There are many creative and beautiful ways to add more plants to a small home like using a backless bookshelf or installing vertical gardens.

Get plants, tools, and expert tips on how to take care of your home garden at SM Mall. You can also find beautiful containers like terrariums and plant hangers that are made by Filipino SMEs.

Buy eco-friendly products

Choose more environmentally friendly products to gradually create a sustainable lifestyle.

Environmentally friendly products can be reusable or biodegradable. They are usually made from sustainable materials with eco-friendly packaging. They also produced less toxic waste during manufacturing and after disposal.

You can find thousands of eco-friendly products within SM malls through the recently launched Green Finds pop-up stores. The selection of products can help go green in every aspect of your life.

Reuse as much as you can

Before you throw anything away, consider if the item can be either upcycled into something useful, or donated to someone who needs it. SM holds regular toy and book drives, where you can even get discount vouchers to use in the store.

Join the Green Movement

The SM Green Movement is a collective effort of SM, its customers, communities, and partners to promote green living, green culture and a green planet. For more information, visit this website.

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5 Tips when buying life insurance for the first time

A knowledgeable and professional insurance agent can offer trusted guidance when it comes to finding the right life insurance protection at the right price.

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Major life changes like getting married, starting a family or buying a house are often when people start thinking about buying life insurance. Now, more than ever, people are more concerned with their financial security. Buying a life policy can be a process that sounds intimidating or confusing – but it’s also very important.

During this Life Insurance Awareness Month, Erie Insurance shares five points to discuss with your agent when buying life insurance for the first time.

  1. Understand who (or what) you are protecting. While anyone experiencing a significant life event like getting married or starting a family often recognizes the need for life insurance, others may not realize they could benefit from it as well. For instance, stay-at-home parents and student loan cosigners could have a definite need for life insurance.
  2. Only buy the life insurance plan you can afford. Many people are surprised at how much life insurance they really need to protect the people and things they love most – but they are also surprised at how affordable it can be. If you cannot find a policy that fits in your budget, it’s a mistake to forgo any coverage at all. Something is definitely better than nothing.
  3. Think through your beneficiaries. A life insurance beneficiary is the person or entity you name in your life policy to receive funds in the event of your passing. Your beneficiary can be a person, business, trust, charity or even your church. And you can have more than one. It’s important to make sure you think through who your beneficiaries are and if any proceeds meant to benefit a minor should be held in a trust.
  4. Buy from a financially sound company. You want the backing of a financially strong insurer if you or someone you love needs to call on the life insurance policy. A.M. Best, the largest and longest-established company devoted to issuing in-depth reports and financial strength ratings about insurance organizations, gave Erie Family Life Insurance Company a rating of A (Excellent).
  5. Consider current and future needs. Don’t just consider your current lifestyle, keep in mind your future needs and what those could include for your spouse, children or business (think college expenses, weddings, etc.). By taking in these considerations today, you’re investing in the security of your future. Life insurance is less expensive than most people think—and that’s especially true when you’re younger. 

A knowledgeable and professional insurance agent can offer trusted guidance when it comes to finding the right life insurance protection at the right price. Life insurance with Erie Family Life offers you the right coverage with flexible options, helping you to build a policy now that is adaptable later.

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