Advertisements

Experts believe Covid can get you again in 28 days. Social distancing & wearing a mask continue remain effective tools

Advertisements

MELBOURNE: My glorious two and a half year streak of negative COVID tests came to an abrupt halt last week after receiving a message confirming that I was one of the last catches of the pandemic.

My case complements the rising steepness of the third Omicron wave in seven months that is currently rolling across Australia.

Shaking from my mild seizure, I was optimistic that I would at least have a few months of reprieve from isolation and testing precautions. But new evidence suggests the possibility of reinfection with newer sub-variants in a shorter time frame.

Advertisements

Experts reduced the protective window of prior infection from 12 weeks to 28 days. The governments of New South Wales, Western Australia and the Australian Capital Territory announced this week that those who previously had COVID will need to be tested after 28 days if they develop symptoms. If positive, they will be treated as new cases.

Re-infection — testing positive for SARS-CoV-2 (the virus that causes COVID) after recovering from a previous infection — is on the rise. Reinfection accounted for 1% of all pre-micron cases in England, but in recent weeks it has accounted for more than 25% of daily cases there and 18% in New York.

We don’t have comparative Australian data yet, but it’s likely to be a similar story given the BA.4 and BA.5 Omicron sub-variants appearing here. They are more easily transmitted and can cause breakthrough infection in those previously vaccinated or infected.

Advertisements

Understanding our risk of re-infection at an individual level will be easier if we break it down into four key factors: the virus, each person’s immune response to a previous infection, vaccination status, and personal protective measures. We can do little about the first two factors, but we can take action on the last two.


Virus


Much has been written about the immune system evading the characteristics of the Omicron subvariants due to multiple novel mutations in the SARS-CoV2 spike protein.

Prior to Omicron, infection with one variant of COVID (alpha, beta, delta) conferred long-term cross-immunity. It also gave effective protection against symptomatic infection.

However, that all changed with the introduction of the Omicron BA.1 sub-variant in late 2021, when studies demonstrated reduced cross-protection from prior infection, which was associated with a less robust antibody response.

Advertisements

Fast forward a few months and we can see that even infection with early Omicron sub-variants (BA.1, BA.2) does not necessarily protect us from their newer siblings (BA.4, BA.5).

See also  Caring Does Not Pay – The Health Care Blog

Kolkata cafe offers ‘lightning masks’ to customers

Advertisements

Kolkata, West Bengal, Oct 18 (ANI): A restaurant in Kolkata has decided to make the “new normal” convenient as the spread of COVID continues. The cafe introduced customized masks for its customers. The zipper function of the masks makes it unique. While eating, you can not take off special masks. “So masks have become mandatory, so when you eat here, go out and eat, when you’re done eating, zip up,” cafe owner Somoshri Sengupta said.

Our response to past infection

How our immune system handled a previous COVID infection could affect how it handles future exposure.

We know that immunosuppressed people are at increased risk of reinfection (or even relapse after infection).

Advertisements

infection).

A large review of COVID infection in the UK shows that in the general population, people who report no symptoms or have lower concentrations of the virus in their PCR swabs with prior infection are more likely to be re-infected than people with symptoms or higher concentrations virus.

This indicates that when the body develops a stronger immune response to the first infection, it builds up a defense against reinfection. Perhaps a thin silver lining for those who were trembling, coughing and spitting from COVID!


Vaccination status


When COVID vaccines were introduced in 2021, they offered superior protection against both severe illness (leading to hospitalization or death) and symptomatic infection.

It is important to note that protection against severe disease is still maintained by our immune system’s response to parts of the virus that did not mutate from the original strain. But variants of Omicron can infect people even if they are vaccinated, as the variants have found ways to avoid being “neutralized” by vaccine antibodies.

A new study shows that six months after a second dose of an mRNA vaccine (such as

and Moderna) levels of antibodies to all Omicron subvariants are markedly reduced compared to the original (Wuhan) strain. That is, the ability of the vaccine to protect against infection with subvariants decreases faster than against the original strain of the virus.

Antibody levels in all variants rose again two weeks after the participants were revaccinated, but BA.4 and BA.5 showed the smallest increase in gain. Interestingly, in this study (and related to our highly immunized population), antibody levels were higher in subjects who were infected and vaccinated. Again, the gain was smaller for the newer Omicron sub-variants.


personal protection


Much of the discussion recently has focused on the ability of COVID to evade immunity. But do not forget that the virus still has to get into our respiratory tract to cause re-infection.

See also  ‘Life is valuable’ | Health Beat

SARS-CoV-2 is transmitted from person to person by airborne droplets and aerosols, as well as by touching contaminated surfaces.

We can prevent transmission of the virus by doing everything we’ve been taught over the past two years – social distancing and wearing a mask when not possible (preferably non-cloth), washing our hands regularly, improving ventilation by opening windows and using an air purifier for poorly ventilated areas. And we can isolate ourselves when we are sick.


Infected future?


There is some encouraging recent data that shows that while re-infection may be common, it is rarely associated with severe disease. It also shows that booster shots provide some modest protection.

Although some (unfortunate) people get re-infected within a short amount of time (less than 90 days), this seems to be unusual and is due to the fact that they are young and mostly unvaccinated.

Plans to roll out mRNA booster vaccines to combat Omicron spike protein mutations promise to restore some

control over these options. However, the development of further mutations will only be a matter of time.

The bottom line is that it will be difficult to avoid infection or re-infection with a variant of COVID in the coming years.

There is little we can do about the evolution of the virus or our own immune system, but we can greatly reduce the risk of serious infection in ourselves (and our loved ones) and disruption of our lives by being vaccinated and vaccinated in a timely manner. following simple infection control methods.

(The article was distributed by PTI through The Conversation)

Ayurveda, immunity and Covid: what works and what doesn’t

Does drinking warm water help? Can turmeric help boost immunity? In this webinar, AYUSH practitioner Dr. Ushakiran and ETPanache.com editor Lopamudra Ghatak discuss how Ayurveda can help you stay healthy during the coronavirus pandemic. Recorded live on April 30 at 15:00. Look.

Advertisements

Leave a Reply

Your email address will not be published.