Quote:The World Health Organization on Monday warned against complacency and urged countries to continue their efforts to curb the spread of the novel coronavirus as the pandemic was getting worse globally, Reuters reported.

There are more than 71.21 lakh coronavirus cases worldwide. Covid-19 has killed over 4.06 lakh people, according to the Johns Hopkins University tracker.

WHO Director General Tedros Adhanom Ghebreyesus said that more than 1,36,000 cases were reported worldwide on Sunday, and this was the most in a single day so far. “More than six months into the pandemic, this is not the time for any country to take its foot off the pedal,” he said in an online briefing.

Quote:Studies show people with the coronavirus are most infectious just at the point when they first begin to feel unwell, World Health Organization (WHO) experts said on Tuesday (Jun 9).

This feature has made it so hard to control spread of the virus that causes COVID-19 disease, but it can be done through rigorous testing and social distancing, they said.

"It appears from very limited information we have right now that people have more virus in their body at or around the time that they develop symptoms, so very early on," Maria van Kerkhove, a WHO epidemiologist and technical lead on the pandemic, told a live session on social media.

Preliminary studies from Germany and the United States suggest that people with mild symptoms can be infectious for up to 8-9 days, and "it can be a lot longer for people who are more severely ill", she said.

(03 February 21, 10:13)mjcn19 Wrote:

Quote:Philippines' coronavirus cases top 527,000

The Philippines now has 527,272 confirmed COVID-19 cases after the Department of Health (DOH) reported 1,658 new cases on Monday, February 1.
 
The DOH reported 58 new deaths due to the coronavirus disease, bringing the death toll to 10,807, while the recoveries are up by 27, raising total recoveries to 487,574.
 
Of the total cases, 28,891 are active. "

Source

Quote:

• Can a COVID-19 vaccine make me sick with COVID-19?
  
  No. None of the authorized and recommended COVID-19 vaccines or COVID-19 vaccines currently in development in the United States contain the live virus that causes COVID-19. This means that a COVID-19 vaccine cannot make you sick with COVID-19.
  
  There are several different types of vaccines in development. All of them teach our immune systems how to recognize and fight the virus that causes COVID-19. Sometimes this process can cause symptoms, such as fever. These symptoms are normal and are a sign that the body is building protection against the virus that causes COVID-19. Learn more about how COVID-19 vaccines work.
  
  
  
• After getting a COVID-19 vaccine, will I test positive for COVID-19 on a viral test?
  
  No. Neither the recently authorized and recommended vaccines nor the other COVID-19 vaccines currently in clinical trials in the United States can cause you to test positive on viral tests, which are used to see if you have a current infection.​
  
  
  
• If I have already had COVID-19 and recovered, do I still need to get vaccinated with a COVID-19 vaccine?
  
  Due to the severe health risks associated with COVID-19 and the fact that re-infection with COVID-19 is possible, vaccine should be offered to you regardless of whether you already had COVID-19 infection. CDC is providing recommendations to federal, state, and local governments about who should be vaccinated first.
  
  At this time, experts do not know how long someone is protected from getting sick again after recovering from COVID-19. The immunity someone gains from having an infection, called natural immunity, varies from person to person.
  
  
• Will a COVID-19 vaccination protect me from getting sick with COVID-19?
  
  Yes. COVID-19 vaccination works by teaching your immune system how to recognize and fight the virus that causes COVID-19, and this protects you from getting sick with COVID-19.
  
  
• Will a COVID-19 vaccine alter my DNA?
  
  No. COVID-19 mRNA vaccines do not change or interact with your DNA in any way.
  
  Messenger RNA vaccines—also called mRNA vaccines—are the first COVID-19 vaccines authorized for use in the United States. mRNA vaccines teach our cells how to make a protein that triggers an immune response. 
  
  
• Is it safe for me to get a COVID-19 vaccine if I would like to have a baby one day?
  
  Yes. People who want to get pregnant in the future may receive the COVID-19 vaccine.
  
  Based on current knowledge, experts believe that COVID-19 vaccines are unlikely to pose a risk to a person trying to become pregnant in the short or long term. Scientists study every vaccine carefully for side effects immediately and for years afterward.  The COVID-19 vaccines are being studied carefully now and will continue to be studied for many years, similar to other vaccines.
  

• Pfizer-BioNTech COVID-19 vaccine
  
• Moderna’s COVID-19 vaccine
  

• AstraZeneca’s COVID-19 vaccine
  
• Janssen’s COVID-19 vaccine
  
• Novavax’s COVID-19 vaccine​
  

Quote:Novavax vaccine trials run in South Africa and the UK indicate that its efficacy in the UK was 89% at least seven days after individuals had received two doses of vaccine. In South Africa, the vaccine efficacy was 60% in people living without HIV. A small group of individuals living with HIV – about 150 – was included in the efficacy analysis. However, the study didn’t have the statistical power to evaluate for vaccine efficacy specifically in this population.

Why the major difference in risk between the UK’s 89% and South Africa’s 60%? 

Quote:...At a time when the answer is more urgent than ever – especially as the British government has decided to delay the second dose of all currently approved Covid-19 vaccines from 3-4 weeks to 12, and Russia is trialling a single-dose regimen of its Sputnik V vaccine named "Sputnik-Light" – it's also surprisingly complicated. Here's what we know so far. 

Pfizer-BioNTech

According to Pfizer data published in December 2020, the Pfizer-BioNTech vaccine is roughly 52% effective after the first dose. Out of 36,523 participants in the phase three trial – the final stage of testing where people either received two full doses, 21 days apart, or a placebo – who had no evidence of existing infection, 82 people in the placebo group and 39 in the vaccine group developed Covid-19 symptoms. However, this early protection comes with some important caveats. First, the protection doesn't kick in until at least day 12 – until then, there was no difference between the two groups. Secondly, one dose is still significantly less protective than two. The latter is 95% effective at preventing the disease after a week.

But there is also another figure that has been circulating on the internet, and anecdotally, being fed to patients by certain doctors – the suggestion that the first dose is around 90% effective. And this is where it gets a little more complicated.

Oxford-AstraZeneca

For the Oxford-AstraZeneca vaccine, things are a bit different. In a paper published in January, the authors explain that the vaccine offers protection of 64.1% after at least one standard dose. This compares to 70.4% if you've had two full doses, or – oddly – 90% in people who have had one half dose followed by one full dose.

Meanwhile, based on these unpublished data they have seen, the Vaccine Committee has estimated that, from three weeks until 9-12 weeks after the first injection, the vaccine prevents around 70% of cases of serious disease.

Because the phase three trial included two gaps between the first and the second dose – including one of six weeks and a longer one of 12 weeks – it's possible to say with more certainty that the first dose can continue to provide some protection for at least a few months before the booster shot.

Moderna

According to a document the company submitted to the FDA, the Moderna vaccine can provide 80.2% protection after one dose, compared to 95.6% after the second (in people aged 18 to 65 – it's 86.4% in those over 65). As with the Pfizer vaccine, all participants in the phase three trial received two doses of the vaccine or a placebo within a single set time period – in this case, 28 days – so it's not yet known whether the immunity from a single vaccine would continue, or drop off after this stage.

Sinovac

The CoronaVac vaccine was developed by Sinovac, a biopharmaceutical company based in Beijing, China. This version is unusual as it has been trialled independently in several countries – all of which have produced different results.

According to researchers in Turkey, the vaccine is 91.25% protective, while scientists in Indonesia have said that it’s 65.3% effective, and the Butantan Institute in São Paulo, Brazil recently announced that the vaccine prevents 50.4% of people from developing symptoms. At the moment, no one has released data on the efficacy of a single dose – these figures only apply to two doses, spaced 14 days apart.

The results have been viewed with some scepticism, because they were published via press releases, instead of – as would normally be the case – in a peer-reviewed journal. Without access to more information about the trial methods and the data that was collected, it’s harder for scientists to make their own assessments of the results' validity. 

Sinopharm

In all, there are five Chinese vaccines at various stages of development.

Another is "BBIBP-CorV", by the state-owned company Sinopharm, based in Shanghai. Officials in the country recently announced that this version is 79% effective after two doses – though by then, it had already been distributed to nearly a million people. This estimate has not been verified by the international community, because the underlying data and methods for its trial have not been made publicly available. It's not yet clear how protective it might be after a single dose.

Outside China, the vaccine is currently being tested all over the world, and has been approved in Bahrain, Egypt, Jordan, the Seychelles, and the United Arab Emirates. The UAE recently became the first to rate its efficacy, claiming via a press release that it is 86% effective...

Quote:Covishield

This vaccine has been developed by the University of Oxford and British-Swedish pharmaceutical company AstraZeneca. Adar Poonawalla, Chief Executive Officer, Serum Institute of India (SII) -- which is British-Swedish pharma giant AstraZeneca's manufacturing partner – said that the vaccine would be 90 to 95 per cent effective if the two shots are parted by around 2-3 months. "You'll be hearing some good news from the UK very soon... It would be a 90-95% effective vaccine if you just keep a two-to-three months' gap between dose 1 and dose 2. They will make that public with documentation."

Covishield, Poonawalla added, is highly effective vaccine against novel coronavirus. The vaccine is being touted as one of the most promising vaccines for India where cost and logistics play a big roll.

Covaxin

Covaxin has been developed by Indian biotechnology company Bharat Biotech and clinical research body Indian Council of Medical Research (ICMR). The NDTV report calls Covaxin an inactivated vaccine -- one of the oldest methods for vaccinating people – which means that whole, inactivated viruses are injected in the body to trigger an immune response. These whole batches of coronavirus must be grown, "killed" using a chemical or heat and then made into a vaccine, making it a longer process, the report says.

According to reports, the recipient of the vaccine will also be handed fact sheet and an adverse effect reporting form where they would have to note down symptoms suffered within the first seven days. The consent form state that the vaccine has demonstrated the ability to produce antibody against coronavirus in phase 1 and phase 2 clinical trials. “However, the clinical efficacy of Covaxin is yet to be established and it is being studies in phase 3 clinical trial,” the report said.