Wednesday, August 26, 2020

Some good news in the world

 https://www.dailymail.co.uk/news/article-8663023/UN-declares-Africa-free-polio.html


Africa is free of polio: World Health Organization declares continent has eradicated the virus after decades-long battle

  • The landmark achievement comes after vaccinations across 47 states
  • There have been zero cases of polio for four years - the threshold for eradication
  • Poliomyelitis attacks the spinal cord and causes irreversible paralysis
  • It paralysed 75,000 children a year in the 90s, when campaigning started    

Africa is free of polio after years of trying to eradicate the virus, the World Health Organization has declared.

The landmark achievement comes after decades of campaigning and vaccination programmes across the continent.

No cases of polio have been diagnosed in Africa in four years — the threshold to certify eradication of the crippling virus. The last case was detected in 2016 in Nigeria, where vaccination efforts had been hampered by Boko Haram jihadists.  

Professor Rose Gana Fomban Leke, chair of the African Regional Certification Commission for Polio eradication, called it a 'historic day' for the continent.  

Poliomyelitis - the medical term for polio - is a contagious virus which attacks the spinal cord and causes irreversible paralysis in children, sometimes within hours.

It paralysed 75,000 children a year in Africa in the 90s, when efforts to eradicate the virus were stepped up. 

A working life-long vaccine wiped out the disease in developed countries like the US and UK but the illness has carried on for years in poorer parts of the world. 

Polio now joins smallpox in the list of viruses that have been wiped out in Africa — 'one of the greatest achievements in public health history', the WHO said. It now only exists in Afghanistan and Pakistan.

There are, however, still rare cases of polio among Africans who haven't had the vaccine because virus fragments in the jab can pass in the faeces of someone who has been vaccinated then mutate and eventually infect unprotected people.  

In other promising developments, the WHO claims Africa's Covid-19 outbreak may have finally passed its peak. More than one million cases and 28,000 deaths have been recorded across the continent since the pandemic began. 

The last remnants of poliovirus in Africa were wiped out thanks to a massive vaccination effort in northern Nigeria, where Boko Haram jihadists had opposed immunisation (Pictured: A child receives a vaccine)

The last remnants of poliovirus in Africa were wiped out thanks to a massive vaccination effort in northern Nigeria, where Boko Haram jihadists had opposed immunisation (Pictured: A child receives a vaccine)

The battle against polio

The battle against polio

Poliovirus is typically spread in the faeces of an infected person and is picked up through contaminated water or food. 

While there is no cure, the disease can be prevented through the administration of a simple and effective vaccine.

Vaccinating people to prevent them from becoming infected thus breaks the cycle of transmission and eventually eradicates the virus in the wild. 

It was endemic — meaning it circulated constantly in the population — around the world until a vaccine was found in the 1950s. 

But this remained out of reach for many poorer countries in Asia and Africa. 

WHAT IS POLIO?

Polio is a serious viral infection that used to be common all over the world.

Most sufferers do not have symptoms and are unaware they have the infection.

For up to one in 100 people, the virus causes temporary or permanent paralysis, which can be life-threatening if it affects their breathing muscles.

Polio incidences fell dramatically when routine vaccination was introduced in the mid-1950s, with no cases being caught in the UK since the mid-90s.

Infection rates are still high in some parts of the world. 

Of those who develop symptoms, these tend to appear three-to-21 days after infection and include:

  • High temperature
  • Sore throat
  • Headache
  • Abdominal pain
  • Aching muscles
  • Nausea and vomiting

These usually pass within a week, however, in less than one per cent of cases the virus attacks the nerves in the spine and base of the brain, which can lead to paralysis. 

People can catch polio via droplets in the air when someone coughs or sneezes, or if they come into contacted with the faeces of an infected person.

There is no cure for polio.

Treatment focuses on easing symptoms.

In the UK, jabs are available as five separate doses as part of the NHS routine childhood vaccination programme.

Source: NHS Choices 

In 1996, African leaders committed to eradicate polio during the 32nd Ordinary Session of the Organization of African Unity in Yaoundé, Cameroon. 

At the time, polio was paralyzing an estimated 75,000 children, annually, on the continent. 

Since then, eradication efforts have prevented up to 1.8million children from crippling life-long paralysis and saved 180,000 lives, the WHO says. 

The last case of polio in Africa was detected in 2016 in Nigeria, where vaccination efforts had been hampered by Boko Haram jihadists. More than 20 workers involved in the campaign lost their lives.

The independent Africa Regional Certification Commission (ARCC) for Polio Eradication officially declared that Africa is free of wild poliovirus, following the eradication of smallpox 40 years ago. 

It comes after an exhaustive, decades-long process of documentation and analysis of polio surveillance and immunisation programmes across 47 countries. 

Dr Matshidiso Moeti, the WHO's regional director for Africa, said: 'This is a momentous milestone for Africa. Now future generations of African children can live free of wild polio.

'This historic achievement was only possible thanks to the leadership and commitment of governments, communities, global polio eradication partners and philanthropists.

'I pay special tribute to the frontline health workers and vaccinators, some of whom lost their lives, for this noble cause.'

'This is one of the greatest achievements in public health history,' WHO chief Tedros Adhanom Ghebreyesus co-wrote in an article in Al Jazeera.

'Delivering polio vaccines to every child in the African region and wiping out the wild virus is no small feat, and the human resources, skills and experience gained in the process leave behind a legacy in how to tackle diseases and reach the poorest and most marginalised communities with lifesaving services,' said Dr Tedros and Holger Knaack, president of Rotary International. 

They said as recently as 2012, half of all globally recorded cases of wild polio virus were in Nigeria — the last country in the region to rid itself of the virus.

THE WORLD'S HISTORY WITH POLIO 

1789: The disease was given its first clinical description by the British physician Michael Underwood.

Late 19th century: Poliomyelitis became a major public health issue in late Victorian times with major epidemics in Europe and the US.

1916: New York experienced the first large epidemic with more than 9,000 cases and 2,343 deaths. Major outbreaks became more frequent during the 20th century.

1953: Dr Jonas Salk, recruited by the University of Pittsburgh, and his associates develop a potentially safe, inactivated (killed), injected polio vaccine. 

1962: The Salk vaccine replaced by the Sabin vaccine for most purposes because it is easier to administer and less expensive. This is the oral polio vaccine (OPV). 

In 1962, Britain switched to Sabin's OPV vaccine, in line with most countries in the developed world. There have been no domestically acquired cases of the disease in the UK since 1982. 

1979: The last case of polio caused by 'wild' virus in US.

1988: Polio had disappeared from the US, UK, Australia and much of Europe but remained prevalent in more than 125 countries. 

The same year, the World Health Assembly adopted a resolution to eradicate the disease completely by the year 2000.  The 'Global Polio Eradication Initiative' (GPEI) was founded in 1988.

1994: The WHO Americas region was certified polio free.

2002: The WHO certified the European region polio-free. 

2012: Polio remained officially endemic in four countries - Afghanistan, Nigeria, Pakistan and India.

2016: The last case of polio in the African continent is recorded in Nigeria.

2020: Africa is declared polio free by The African Regional Certification Commission for Polio eradication (ARCC). Polio remains endemic in only two countries - Pakistan and Afghanistan. 

Sources: the WHO, OurWorldInData

While the eradication of wild poliovirus from the WHO African Region is a major achievement, 16 countries in the region are currently experiencing circulating vaccine-derived poliovirus (cVDPV) outbreaks.

At least 177 people have been diagnosed with vaccine-derived polio this year, the BBC reported. 

This form of the disease can spread among people who have not had the jab but live close to people who have.

The polio vaccine uses a damaged form of the virus to trigger an immune response in people who get the jab, and those damaged viruses are eventually passed out of the body in faeces.

In some rare cases it is possible for the viruses to mutate and become infectious again, and they can then trigger illness in people who are not vaccinated and come into contact with the faeces or contaminated water or food. 

This cannot happen if everyone is vaccinated, but coverage is around 95 per cent in Africa meaning many people remain unprotected. 

It is among those unprotected people, living close to others who have had the vaccine, that the vaccine-derived polio cases occur.

But Africa has now eliminated all strains of 'wild' polio, which means there are no naturally-occuring strains of the virus circulating in people. 

The vaccine-derived infections are significantly less common than wild ones would be if there was no vaccine. 

Because of global efforts to wipe out the disease – efforts costing some $19 billion over 30 years – only two countries (Afghanistan and Pakistan) have recorded cases of wild polio this year. Between them, 87 cases have been diagnosed. 

Dr Tedros said: 'A surge of resources and effort is needed to ensure that the world uses this critical window of opportunity to protect all children in Afghanistan and Pakistan in the upcoming low season, during which there is a natural decline in cases of the polio virus.'

He said vaccination programmes had been paused in those countries during the Covid-19 pandemic.

It comes as WHO chiefs claim Africa may have passed the peak of its Covid-19 outbreak.

WHO Africa regional director Dr Moeti told a conference of African health ministers yesterday that numbers of new cases were declining, but warned against complacency to avoid a second wave.

'We are seeing that we have had what seems to have been a peak, and now we have the daily numbers of cases being reported overall in the region going down,' she said during an online meeting.

But there are still a few countries, such as Namibia, experiencing increases in daily cases.

Africa has recorded nearly 1.2million cases and at least 28,000 deaths since the virus arrived on the continent on February 14.

South Africa has more than half of those infections and is the fifth worst-hit country in the world.

While numbers of cases and deaths are also declining, Health Minister Zweli Mkhize cautioned that 'our biggest worry is whether in fact this is the first surge and there might be another one'.

'We have gone past our apex, our surge, but if you look at Spain it started showing a surge after a long lull,' he told the same meeting.

Dr Moeti lauded African leaders for taking 'extremely courageous, difficult decisions' to 'avert the catastrophe foretold in early projections of how this virus would affect the African region'.

There had been fears that Africa's poor health systems would collapse under the weight of the pandemic. 

But the situation continues 'to be very grave', Dr Moeti warned.

Many governments are starting to lift the lockdown rules imposed to limit the spread of the virus which means 'increase vigilance is required'.  

Lady of the Flies

 This summer was quite cool compared to the last two and so I had no temporary 'house mates', that is to say 'flies', until it heated up a couple of weeks ago.

Then all of a sudden, along with the heat came the flies. I don't know how so many can find their way into my kitchen but not out of it again, even though the door to the balcony is always open. Sometimes I enter the kitchen and it's like a disco for flies there: their humming sounds like techno music and they're all twirling about.

On the one hand, they annoy me with their noisiness, but on the other, as I live and work alone, I almost welcome them as some company. Then again, I feel guilty that they are basically captive in my kitchen.

So I try to get them out by wrenching open the door and getting behind them and walking towards the door, almost pushing them towards freedom again. Most of the time it works.

There are times, however, when they stray into other rooms and I don't always notice it until it's too late, until I find a poor little jewelled body, shining in dark rainbow colours, lying on the ground or window sill, dead from exhaustion after hours of banging against the window pane. Poor wee things.

Thursday, August 20, 2020

"There's no such thing as global warming or climate change." Yeah, right.

How people can blithely turn a blind eye to what is happening in the natural world, I just don't know. It seems they don't realise that they live in this world and that the way we're heading, we're going to be facing some very desperate times. This coronavirus pandemic will seem like a walk in the park in comparison.

Here is a mind-boggling figure for you:

Greenland ice sheet lost a record 1m tonnes of ice per minute in 2019

Climate-driven loss is likely to be the worst for centuries, and is pushing up sea levels

Arctic sea ice in the Denmark Strait on the east coast of Greenland
 Arctic sea ice in the Denmark Strait on the east coast of Greenland. Photograph: Nasa Handout/EPA

The Greenland ice sheet lost a record amount of ice in 2019, equivalent to a million tonnes per minute across the year, satellite data shows.

The climate crisis is heating the Arctic at double the rate in lower latitudes, and the ice cap is the biggest single contributor to sea level rise, which already imperils coasts around the world. The ice sheet shrank by 532bn tonnes last year as its surface melted and glaciers fell into the ocean and would have filled seven Olympic-sized swimming pools per second.

The satellite data has been collected since 2003. The 2019 loss was double the annual average since then of 255bn tonnes. Almost that amount was lost in July 2019 alone.

Scientists knew that ice loss from Greenland had been accelerating fast in recent decades and that there had been high rates of melting in 2019. But the satellite data accounts for new snowfall and allows the net loss to be calculated. The researchers said the scale of the 2019 loss was shocking and was likely to be the biggest in centuries or even millennia.


If the entire Greenland ice sheet melts, sea level would rise by six metres. But the researchers said it was not certain that the sheet had passed the point of no return and that cutting carbon emissions will slow the melting, which would take centuries to complete.

“[2019 was] really shocking and depressing in terms of the numbers,” said Ingo Sasgen, of the Alfred Wegener Institute in Bremerhaven, Germany, who led the analysis. “But it’s also not very surprising, because we had other strong melt years in 2010 and 2012, and I expect we will see more and more.”

Snowfall in Greenland was low in 2019, also due to the blocking pattern, meaning relatively little new ice was added. “The real message is that the ice sheet is strongly out of balance,” Sasgen said.

Weather data and computer models allow for losses to be calculated back to 1948. “If we look at the record melt years, the top five occurred in the last 10 years, and that is a concern. But we know what to do about it: reduce CO2 emissions.”

Sasgen said a further worry was feedback mechanisms that increase ice loss, including meltwater weakening the ice sheet and speeding its fall into the ocean. Hotter weather also melts the white snow on top of the sheet, revealing darker ice below, which absorbs more of the sun’s heat.

“These results come at a crucial time,” said Yara Mohajerani, of the University of California Irvine in the US, who was not part of the study team. “2019 broke the previous record of 2012 by 15%, itself an unmatched record over the past several centuries to millennia.”

He said the heating of the Arctic was likely to increase further in coming years. “So it is crucial to closely monitor the changes in [ice] mass of the sheet, and Sasgen and his colleagues have taken an important step in that direction.”

The research, published in the journal Communications Earth & Environment, used data from the Nasa’s Grace satellites, which take gravity measurements and in effect weigh the mass of ice in Greenland.

The first Grace satellite ended its data collection in June 2017, and its replacement began in May 2018. Data from the second satellite was used to determine how much had been lost in the intervening period.

The researchers found 2017 and 2018 had unusually low ice loss, owing to a reversal of the blocking pattern that resulted in cold, snowy conditions fixed over Greenland. But even in these conditions the sheet still lost ice, meaning cold years do not compensate for the hot ones as in the past.

“It really shows that we have entered a completely different state,” with a trend of increasing ice losses and more variability each year, Sasgen said. “Greenland has become bipolar in a way.”

Prof Stefan Rahmstorf, of the University of Potsdam in Germany, said the new analysis was convincing and showed the transition from the old to the new satellite had worked smoothly.

“Since meltwater is freshwater, it dilutes the salt content of the surrounding ocean, which contributes to slowing the Gulf stream system,” Rahmstorf said. “If we wanted to make the 500bn tonnes of freshwater added in 2019 as salty as ocean water, about 200,000 Panamax-class cargo ships full of salt would need to dump their load into the Atlantic.”

Despite the rapid melting, the Greenland ice sheet is not necessarily doomed to melt entirely. Firstly, as glaciers retreat they lose contact with warmer ocean waters and therefore melt less. Secondly, the melting of the sheet with warm air takes centuries, during which time the rise in global temperatures might be reversed.

“If we reduce CO2, we will reduce Arctic warming and we will therefore also reduce the sea level rise contribution from the Greenland ice sheet,” Sasgen said. “So even though it might eventually disappear in large part, it happens much slower, which would be better as it would allow more time for the 600 million people living near coasts to move away.”

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