‘The head of WHO Europe was today pessimistic about vaccines’ ability to put an end to the Covid pandemic, as new variants dash hopes of reaching herd immunity. Faced with the possibility that the virus may be around for many years, health officials must now “anticipate how to gradually adapt our vaccination strategy”, in particular on the question of additional doses, Hans Kluge told reporters.’
Read here (Free Malaysia Today, Sept 10, 2021)
‘We have all been occupied by the political situation in the country, but the Covid-19 virus is not. It is continuing its relentless march forward, whether we are focused on it or not. While an efficient government that deals with the pandemic decisively is crucial for the country, Malaysians need to be prepared for what is coming our way. I would like to share with you some possible scenarios for the coming weeks and months, and some thoughts and opinions based on current data.
Read here (Code Blue, August 19, 2021)
‘A stronger push towards wider vaccination and herd immunity will be key to domestic recovery and should facilitate an economic rebound as emergence of new Covid-19 variants poses high risk, Moody's Analytics economist Sonia Zhu said. Malaysia's economy contracted by 0.5% year-on-year in the March quarter, following a 3.4% slump in the fourth quarter of 2020.
"Despite a gradual easing of gross domestic product (GDP) contractions, conditions will likely stay weak in the coming quarter due to the latest Movement Control Order (MCO)," she said in a statement today... "Hence, a stronger push towards wider vaccination is key," she said, adding that at present, only 3.4% of Malaysia's total population has received at least one dose of a vaccine.
‘The slow vaccination rate casts doubt on the ability to reach herd immunity target by the end of 2021, tilting the balance of risks to the downside for the subsequent quarter, opined Zhu.’
Read here (The Edge, May 14, 2021)
‘With neither vaccinations to provide herd immunity nor control measures to reduce the infectivity rate, it looks like the government has indeed lost control of the fight against Covid 19, and we, the people, may have to pay the price.
‘There is a terribly urgent need to increase the vaccination rate. While this is being done, controls must be reimposed. It is a time for tough decisions, and one can only hope that this backdoor government will put politicking on the back-burner, and prioritise the last big battle against Covid-19 and minimise the damage.
‘To simply wait for vaccination to take its course and stop the pandemic may result in far too many casualties.’
Read here (The Vibes, Apr 20, 2021)
‘Manaus and cities like it will continue to generate dangerous viral variants if vaccination campaigns are not expanded to broadly reach all nations, rich or poor...
‘Manaus was devastated by a first wave of COVID cases beginning last March. Excess deaths—the 3,457 people in the city who died above the expected mortality figures between March 19 and June 24, 2020—represented 0.16 percent of Manaus’s relatively young population. And 7 percent of men older than 75 died at the peak of the spread.
‘Infections were so prevalent that researchers at the University of São Paulo and their colleagues concluded that Manaus was the first city in the world to reach herd immunity—the point at which enough people are immune to a virus that the spread of new infections is hindered. Their preliminary preprint study estimated that 66 percent of the population had been infected with SARS-CoV-2 (they later revised their figure to 76 percent as of October). The threshold for COVID herd immunity is unknown, but projections often cited range from 60 to 90 percent. Similarly high rates of infection have also been found in the Peruvian and Colombian Amazon...
‘In December 2020 a second wave did hit. And by January the city’s health system, which serves communities across the Amazon, had collapsed. ICUs were full to bursting, and oxygen supplies became exhausted. Some patients were airlifted to other regions of Brazil. But many died of asphyxiation on makeshift beds in hospital corridors or their home, doctors say.
‘More severe than the first one, the new wave took Manaus by surprise. Wearing masks and practicing social distancing had been discarded in the belief the city had reached herd immunity. Caseloads surged out of control, and bleak milestones from last year were surpassed. In January alone more than 3,200 excess deaths were logged, Orellana says.’
Read here (Scientific American, Mar 29, 2021)
The Sars-CoV-2 virus is changing in ways that are making it more transmissible, increasing the severity of disease it causes and allowing it to infect people who should have immunity. These variants are causing concern among global health experts, particularly as there are signs that some vaccines may be less effective against them.
Here are five things to know about the new Covid-19 variants:
Read here (Horizon, Mar 29, 2021)
‘Malaysia will allow its private healthcare providers to open negotiations to procure their own Covid-19 vaccine supplies, the government said on Monday (March 29).
‘However, the country's coordinating minister for its immunisation programme, Mr Khairy Jamaluddin, tempered expectations by warning that a private sector vaccine roll-out - which would allow individuals to pay for their own Covid-19 vaccine - might take place only in the second half of 2021.
‘Mr Khairy said that he would hold discussions with private hospitals about allowing them to procure vaccines, following a request by the Association of Private Hospitals of Malaysia (APHM) to run a parallel vaccination drive along with the government's free vaccination programme to help the country achieve herd immunity against the coronavirus.’
Read here (Straits Times, Mar 29, 2021)
‘No doubt you’ve heard about the novel coronavirus variants that are evolving around the world. There now appear to be more than a dozen versions of SARS-CoV-2, which are of varying degrees of concern because some are linked to increased infectivity and lethality while others are not. It’s easy to be overwhelmed by this diversity and to fear that we’ll never achieve herd immunity. Yet evidence is growing that these variants share similar combinations of mutations. This may not be the multifront war that many are dreading, with an infinite number of new viral versions.’
Read here (Scientific American, Mar 24, 2021)
As Covid-19 vaccination rates pick up around the world, people have reasonably begun to ask: how much longer will this pandemic last? It’s an issue surrounded with uncertainties. But the once-popular idea that enough people will eventually gain immunity to SARS-CoV-2 to block most transmission — a ‘herd-immunity threshold’ — is starting to look unlikely.
Read here (Nature, March 18, 2021)
‘To achieve herd immunity against Covid-19, a substantial proportion of a population would need to be vaccinated but we are currently uncertain as to what this percentage is. In some diseases like measles 90-95 per cent of a population need to be vaccinated to achieve herd immunity; in others like polio we require about 80 per cent.
‘It is very likely that for Covid-19 we will require at least 75-85 per cent of the population to be vaccinated. This can be supplemented by those who had prior infection with Covid-19.’
Read here (Malay Mail, Mar 18, 2021)
‘A February 18 Opinion piece in the Wall Street Journal is raising hopes, and possibly healthy skepticism, with its title and thesis being: “We’ll Have Herd Immunity by April.” The author is Dr. Martin Makary, a professor of health policy and management and public health expert at Johns Hopkins University. He notes that the media is under reporting on the dramatic fact that COVID-19 cases are down 77 percent just in the last six weeks. Largely this is, “because natural immunity from prior infection is far more common than can be measured by testing.”
‘Applying some statistics to the case data, we could deduce the around 55 percent in the US have natural immunity. At the same time, vaccinations have been rolling out, and 15 percent of Americans have gotten a vaccine with the percentage rising fast. Based on these factors, “There is reason to think the country is racing toward an extremely low level of infection. As more people have been infected, most of whom have mild or no symptoms, there are fewer Americans left to be infected. At the current trajectory, I expect Covid will be mostly gone by April, allowing Americans to resume normal life.”
Read here (TrialSiteNews, Feb 20, 2021)
‘In January, Nature asked more than 100 immunologists, infectious-disease researchers and virologists working on the coronavirus whether it could be eradicated. Almost 90% of respondents think that the coronavirus will become endemic — meaning that it will continue to circulate in pockets of the global population for years to come (see 'Endemic future')...
‘More than one-third of the respondents to Nature’s survey thought that it would be possible to eliminate SARS-CoV-2 from some regions while it continued to circulate in others. In zero-COVID regions there would be a continual risk of disease outbreaks, but they could be quenched quickly by herd immunity if most people had been vaccinated.’
Read here (Nature, Feb 16, 2021)
‘In fact, most vaccines don't fully protect against infection, even if they can block symptoms from appearing. As a result, vaccinated people can unknowingly carry and spread pathogens. Occasionally, they can even start epidemics.
"Effective" or "sterilising" immunity: There are two main types of immunity you can achieve with vaccines. One is so-called "effective" immunity, which can prevent a pathogen from causing serious disease, but can't stop it from entering the body or making more copies of itself. The other is "sterilising immunity", which can thwart infections entirely, and even prevent asymptomatic cases. The latter is the aspiration of all vaccine research, but surprisingly rarely achieved.
What type of immunity do the Covid-19 vaccines provide? "In a nutshell we don't know, because they’re too new," says Neal. So far, the available Covid-19 vaccines have not been judged primarily on their ability to prevent transmission – though this is now being evaluated as a secondary endpoint for many of them. Instead, their efficacy was assessed by whether they could prevent symptoms from developing. "This means that we set our targets kind of pragmatically," says Danny Altmann, professor of immunology at Imperial College London.’
Read here (BBC, Feb 4, 2021)
‘Let us look at the numbers - our population is 31 million. We have six million migrant workers and another 200,000 refugees. So altogether there are 37.2 million people residing in Malaysia.
‘The government has said that children and pregnant women will not be given the Covid vaccine - that is about six million children 12 years and below and 0.5 million pregnant women. 6.5 million is 17.5 percent of 37.2 million.
‘In other words, we could achieve our 80 percent immunisation rate if all migrant workers also took the vaccine. But if all of them didn’t, then we would have 12.7 million not vaccinated - children, pregnant mums, migrant workers and refugees - and 12.7 million is 34 percent of 37.2 million. We only achieve a vaccination rate of 63 percent - far short of the 80 percent we need to get herd immunity!’
Read here (Malaysiakini, Jan 30, 2021)
‘A study published in The Lancet analyzed the increased SARS-CoV-2 transmission in Manaus, Brazil, a region that had previously shown high levels of seroprevalence among its community members. A study conducted in October 2020 detected SARS-CoV-2 antibodies in samples from 76% of blood donors, which suggested that the region may have reached the threshold to provide some level of community immunity (ie, herd immunity). Despite the high seroprevalence, Manaus exhibited a large surge in COVID-19 cases and hospitalizations in January 2021.
‘The researchers present 4 possible explanations for the surprising surge in cases. First, the previous study could have overestimated the seroprevalence, which could have put the community below the herd immunity threshold. Second, immunity to SARS-CoV-2 conferred by earlier infection could have waned, resulting in re-infections. Third, the new infectious could be a result of emerging variants, including the P.1 variant first reported in the area, that are less susceptible to antibodies from prior infections. And finally, new SARS-CoV-2 lineages could simply be exhibiting much higher transmissibility, which could allow widespread community transmission even in areas with high existing seroprevalence. The researchers note that these theories are not mutually exclusive, and further study is needed to better characterize the factors driving the current resurgence. In particular, it is critical to investigate the potential that emerging variants could evade antibodies developed from infection with other strains, which could inform response activities in communities around the world.’
Read here (The Lancet, Jan 27, 2021)
‘Vaccinating kids, however, is often not just about the direct and immediate benefits to them. It’s also meant to protect children against diseases that would otherwise become more dangerous for them as adults—measles, mumps, and chicken pox are three common examples—and dampen the overall spread of these diseases. In the short term, the primary reason to vaccinate children against COVID-19 may be that the U.S. will have a hard time reaching herd immunity otherwise.‘
Read here (The Atlantic, Jan 21, 2021)
‘Influenza may provide the best blueprint of what to expect going forward. The most common flu vaccine—the inactivated virus—is not “truly sterilizing because it doesn’t generate local immune response in the respiratory tract,” Crowcroft says. This fact, coupled with low immunization rates (often shy of 50 percent among adults) and the influenza virus’s ability to infect and move between multiple species, enables it to constantly change in ways that make it hard for our immune system to recognize. Still, depending on the year, flu vaccines have been shown to reduce hospitalizations among older adults by an estimated 40 percent and intensive care admissions of all adults by as much as 82 percent.
‘Research on seasonal coronaviruses suggests that SARS-CoV-2 could similarly evolve to evade our immune systems and vaccination efforts, though probably at a slower pace. And data remain mixed on the relationship between symptoms, viral load and infectiousness. But ample precedent points to vaccines driving successful containment of infectious diseases even when they do not provide perfectly sterilizing immunity. “Measles, diphtheria, pertussis, polio, hepatitis B—these are all epidemic-prone diseases,” Crowcroft says. “They show that we don’t need 100 percent effectiveness at reducing transmission, or 100 percent coverage or 100 percent effectiveness against disease to triumph over infectious diseases.”
Read here (Scientific American, Jan 18, 2021)
‘The World Health Organization’s chief scientist warned that even as numerous countries start rolling out vaccination programs to stop COVID-19, herd immunity is highly unlikely this year.
‘At a media briefing on Monday (Jan 11), Dr Soumya Swaminathan said it was critical countries and their populations maintain strict social distancing and other outbreak control measures for the foreseeable future. In recent weeks, Britain, the US, France, Canada, Germany, Israel, the Netherlands and others have begun vaccinating millions of their citizens against the coronavirus.’
Read here (Channel News Asia, Jan 12, 2021)
‘In this short video, Yale’s Dr. Howard Forman, physician and professor, discusses herd immunity — what it is and how to achieve it for maximum benefit in the age of COVID-19.’
View here (Yale News, Jan 6, 2021)
‘Herd immunity against the novel coronavirus could require vaccination rates "between 70 per cent and 90 per cent", Dr Anthony Fauci, the most prominent US infectious disease expert, said in an interview published on Thursday (Dec 24). More than 1 million Americans have received a first dose of a vaccine since Dec 14, according to the US Centers for Disease Control, or only about 0.3 per cent of the population.
‘Fauci, who is advising both President Donald Trump and President-elect Joe Biden on the pandemic, acknowledged that he had incrementally increased his estimates from earlier in the year, when he tended to say only 60 per cent to 70 per cent would need to be inoculated for herd immunity to be reached.’
Read here (Channel News Asia, Dec 25, 2020)