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What scientists are doing to develop a vaccine for the new coronavirus – The Conversation Africa

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With an increasing number of confirmed cases in China and 24 other countries, the COVID-19 epidemic caused by the novel coronavirus (now known as SARS-CoV-2) looks concerning to many. As of Feb. 19, the latest numbers listed 74,280 confirmed cases including 2,006 deaths. Four of these deaths have occurred outside of mainland China: one each in the Philippines, Japan, Hong Kong and France. The case in France is the first COVID-19 death outside of Asia.

The World Health Organization (WHO) declared on Jan. 30 that the outbreak constituted a Public Health Emergency of International Concern.

In light of these events, health experts around the world are now divided as to whether this event will become a pandemic, or whether it will be possible to contain transmission of this virus.

Towards a pandemic?

In a recent New York Times article Dr. Thomas R. Frieden, former director of the Centers for Disease Control and Prevention, said it was “increasingly unlikely that the virus can be contained.” In the same article, Dr. Anthony S. Fauci, director of the U.S. National Institute of Allergy and Infectious Disease (NIAID), said, “It’s very, very transmissible, and it almost certainly is going to be a pandemic.”

On the other hand, the WHO remains optimistic. Its head of emergency responses, Dr. Michael Ryan, told STAT News, “there’s enough evidence to suggest that this virus can still be contained” and that “until [containment] is impossible, we should keep trying.”

This brings us to the scientists and experts who are doing just that, throwing everything they have at this public health issue. Some are focused on treating patients with existing or novel therapeutics, others are focused on stopping transmission between individuals by developing a vaccine. Luckily for scientists, lessons learned during the 2013-16 West African Ebola epidemic are now enabling the fast-track development of vaccines, without compromising their safety and efficacy.

Of course, it is critical to learn more about this specific novel virus, including its source and why transmission appears to be more efficient than with other coronaviruses.

Vaccine development

CEPI, the Coalition for Epidemic Preparedness Innovations, is an international, not-for-profit organization with the mandate of accelerating the development of vaccines against emerging infectious diseases. On Jan. 23, it announced financial support to three institutions for the development of a vaccine against the newly identified coronavirus: Inovio Pharmaceuticals Inc. and its “DNA platform,” the University of Queensland and its “protein clamp platform” and a Moderna Inc. partnership with NIAID using its “mRNA platform.”

On Jan. 31, CEPI also announced an extended partnership with CureVac, a biotechnology company, to adapt its RNA vaccine platform to SARS-CoV-2. Four days later, CEPI launched a call for proposals to develop new vaccines against the novel coronavirus, open to all organizations meeting its criteria and in possession of a readily available platform.

People wearing surgical masks sitting in the Shanghai metro in January 2020. The novel coronavirus that originated in Wuhan has spread to many cities in China.
(Robert Wei/Shutterstock)

Johnson & Johnson has also announced its participation in vaccine development, using its “adenovirus platform,” which consists of a virus that is modified to look like SARS-CoV-2, but is unable to cause disease in humans. GlaxoSmithKline, another large pharmaceutical company, recently announced a partnership with CEPI to offer access to anyone who would like to use its adjuvant platform (adjuvants are components that can be added to vaccines to increase the generation of an immune response).

Finally, adding its name to the list, the University of Hong Kong also announced it already had a vaccine, designed from a modified influenza virus vaccine.

Issues and solutions

But what do these platforms mean? Why are so many different organizations working towards the same goal of developing a vaccine against one pathogen? Wouldn’t it be easier if everyone worked together, instead of trying such a wide variety of approaches? The answers to these questions are not so simple.

Vaccine platforms are tools that scientists can use to develop a new vaccine, using a similar system to previously successful approaches. For example, one well-known and straightforward approach is the “inactivated platform,” where the pathogen is safely replicated in laboratories, inactivated and then administered as a vaccine.

Although these platforms use different approaches, they all have the same overall goal of training the immune system of the vaccinated individual to quickly recognize a pathogen inside the body.




Read more:
Coronavirus grown in lab outside China for first time, aiding the search for vaccine


So why are there so many different platforms? Well, each platform has its own advantages and disadvantages. Some are easier to mass produce, some are known to induce fewer side effects, and some are just better at training particular aspects of the immune system.

The human immune system is divided into two major arms: innate and adaptive. Our innate immune system is non-specific and provides an immediate, but limited level of protection against a foreign intruder inside the body. The adaptive immune system can target a specific pathogen, but needs time to develop its full effect, about 21 to 28 days following infection, or vaccination. The adaptive side can be further sub-divided into humoral and cellular immunity.

With new pathogens like SARS-CoV-2, scientists don’t know which sub-division of the immune system will provide protection, so they aren’t certain which platform will produce the most successful vaccine.

What are scientists doing then?

Vaccine design looks simple on paper, but making it work all the way to human use is a whole other story.

Currently, scientists are working on identifying which parts of SARS-CoV-2 they can use in their vaccines. These parts have to be carefully selected, because they need to mimic what a real infection would look like to our bodies. This has to be done in conjunction with selection of an appropriate vaccine delivery method: the platform that will be used.

Coronaviruses, like MERS CoV seen here, are named for their appearance under a microscope: projections give the edges of these viruses a characteristic corona, or crown-like shape.
(NIAID)

For ethical reasons, once a vaccine candidate is available, it needs to undergo safety and efficacy testing in animals (although exceptions are possible). Not all laboratory animals are susceptible to infection in the same way as humans. This is why scientists are also working to identify an animal model suitable for evaluating candidate vaccines. At this point, many months and tens of thousands of dollars have been invested in vaccine development.

Once animal trials are satisfactory, the vaccine can be administered to humans in a clinical trial to evaluate the vaccine’s safety and efficacy. This means additional months to years (if not decades), and millions of dollars in investment.

The last steps are often out of the scientists’ hands. The vaccine must be registered and receive regulatory approval, produced at large-scale and distributed. Although these steps take only a few lines to list here, they can take years to actually achieve.

On the other hand, health experts tell us over and over again that if we’re lucky and everything goes well, we could have a safe and effective vaccine in about a year. It remains to be seen at what stage of the process we will be in early 2021. If China has managed to build a 1,000-bed hospital in 10 days to counter the spread of the epidemic, who knows what can be achieved in a year on the vaccine side.

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Why it's important to tell people that monkeypox is predominantly affecting gay and bisexual men – Medical Xpress

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<div data-thumb="https://scx1.b-cdn.net/csz/news/tmb/2022/why-its-important-to-t.jpg" data-src="https://scx2.b-cdn.net/gfx/news/2022/why-its-important-to-t.jpg" data-sub-html="Monkeypox particles in an infected cell. Credit: NIAID, CC BY“>

<img src="https://scx1.b-cdn.net/csz/news/800a/2022/why-its-important-to-t.jpg" alt="Why it's important to tell people that monkeypox is predominately affecting gay and bisexual men" title="Monkeypox particles in an infected cell. Credit: NIAID, CC BY” width=”800″ height=”530″>
Monkeypox particles in an infected cell. Credit: NIAID, CC BY

Monkeypox virus, or MPXV, is an emerging threat to public health. The World Health Organization recently declared the current outbreak a global public health emergency.

For decades, several African countries have experienced ongoing outbreaks of MPXV, driven primarily by contact with animals and transmission within households. However, before last year, most people in Europe and North America had never even heard of the disease. That was until the among gay, bisexual and other men who have sex with men.

Debates over the epidemiology of MPXV

Over the past several months, a controversy has raged about whether it’s OK to say that the current MPXV outbreak is primarily affecting gay and bisexual men, and that it is primarily being spread through close personal contact, such as sex.

As a social and behavioral epidemiologist working with marginalized populations, including gay and bisexual men, I believe it’s important that people know that sexual and gender minority men are the primary victims of this MPXV outbreak. I believe this knowledge will help us end the outbreak before it bridges into other communities.

For reference, more than 90% of cases in non-endemic countries have been transmitted through intimate , and the vast majority of cases are among gay men. Very few cases are linked to community transmission.

While these statistics are undisputed, some have feared that identifying sexual behavior as the primary cause of current MPXV transmission would dampen the public health response. Others have warned that connecting MPXV to an already stigmatized community will worsen stigma towards gay sex.

Non-sexual transmission is possible, and a considerable threat

It is true that MPXV can transmit through more casual contact and through fomites (inanimate objects on which some microbes can survive, such as bed linens, towels or tables).

However, months into the current outbreak, we have not seen these routes emerge as important pathways of transmission. This may be due to changes in the fundamental transmission dynamic of MPXV or due to enhanced cleaning procedures implemented in response to COVID-19 in places such as gyms and restrooms.

Why it’s crucial to know MPXV affects gay and bisexual men

Informing the public about MPXV is important because plays an important role in shaping public health policies, such as who gets access to vaccines and what interventions are used to stop .

A recent study conducted by my team aimed to demonstrate the importance of public health education by asking Canadians to participate in a discrete choice experiment.

We asked participants to choose between two hypothetical public health programs across eight head-to-head comparisons. Descriptions for each hypothetical program identified the number of years of life gained by patients, the it addressed and the population it was tailored for.

From our analyses of this data, we learned a lot about how the public wants public health dollars to be spent and how their knowledge and bias shapes these preferences. There were five major takeaways:

  1. People preferred interventions that added more years to participants’ life expectancy. In fact, for one year of marginal life gained, there was a 15% increase in the odds that participants chose that program.
  2. We found that people tended to favor interventions that focused on treatment rather than prevention. While this approach is emotionally intuitive, large bodies of evidence suggest that it is more cost-effective to prevent disease than to treat it. As the old saying goes: An ounce of prevention is worth a pound of cure.
  3. People generally preferred interventions for common chronic diseases—such as , diabetes and cancer—and were less likely to favor interventions for behavior-related conditions, such as sexually transmitted infections.
  4. People generally preferred programs focused on the general population as opposed to those tailored for key marginalized populations. In fact, people were least likely to prefer interventions tailored for sexual and gender minorities.
  5. The bias against behavioral interventions and those tailored for key populations was overcome when the programs addressed a health condition that was widely understood to be linked to the population the program was tailored to. For example, people were more likely to support interventions for sexually transmitted infections when these interventions were tailored for people engaged in sex work or for gay and .

This study highlights why it is important to educate the public about inequities. People are smarter, more pragmatic, and more compassionate than we give them credit for. If we take the time to share evidence with them about the challenges that stigmatized communities face, they will be more willing to support policies and efforts to address these challenges.

Ending MPXV quickly is critical, especially since the virus has the potential to evolve in ways that could make the disease more infectious. Protecting gay and bisexual men first, protects everyone.

We should, of course, always be aware of the potential harms and the corrosive effects of stigma. However, in , honesty really is the best policy.


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Monkeypox: An expert explains what gay and bisexual men need to know


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How Worried Should You Be About New Reports on Polio? – The Suburban Newspaper

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MONDAY, Aug. 15, 2022 (HealthDay News) — Poliovirus detected in New York City wastewater last week put public health officials on high alert, as it indicates the potentially paralyzing virus is circulating widely in the area.

But infectious disease experts say there’s no need for families of fully vaccinated children to panic.

“The inactivated polio vaccine is part of the standard childhood immunization schedule, so for most families, it really shouldn’t be a concern,” said Dr. Gail Shust, a pediatric infectious diseases specialist at NYU Langone Hassenfeld Children’s Hospital in New York City. “It happens to be an extremely effective vaccine.”

At this point, there’s also no need to seek out a polio booster for a fully vaccinated child or adult, she added.

“For kids who’ve gone through the normal vaccination schedule in the United States, there is zero reason for them to get a booster,” Shust said.

Instead, concern should be focused on communities with clusters of unvaccinated children and adults, because those are the people at risk for polio, experts say.

A young man in Rockland County, N.Y. — about 45 minutes northwest of the Bronx — was diagnosed in late July with the first case of paralytic polio identified in the United States in nearly a decade.

Subsequently, poliovirus was detected in the sewage of both Rockland County and neighboring Orange County, indicating community transmission of the virus.

Polio can lead to permanent paralysis of the arms and legs. It also can be fatal if paralysis occurs in muscles used to breathe or swallow.

About 1 in 25 people infected with poliovirus will get viral meningitis, and about 1 in 200 become paralyzed.

“A lot of people who get infected with poliovirus, they’re asymptomatic,” Shust said. “It’s entirely possible there are other cases that haven’t been diagnosed and there are more people infected than we’re aware of.”

Children should receive at least three doses of polio vaccine by 18 months of age, with a fourth dose delivered between ages 4 and 6, according to the U.S. Centers for Disease Control and Prevention.

New York state health officials said they are particularly concerned by neighborhoods where fewer than 70% of children between 6 months and 5 years of age have received at least three doses of polio vaccine.

About 86% of New York City kids have gotten all three doses, but in Rockland County the rate is just over 60%, and in Orange County the rate is just under 59%, state health officials said.

Statewide, nearly 79% of children have received three doses by their second birthday, officials said.

Poliovirus also has been identified in London’s wastewater, and health officials in the United Kingdom have decided to offer polio vaccine boosters to children.

“They’re starting to do that in London. We haven’t said that that’s necessary,” said Dr. William Schaffner, medical director of the Bethesda, Md.-based National Foundation for Infectious Diseases.

“The only time we’ve given boosters in the past is when someone who was vaccinated as a child then decided to travel to some developing country where there was a lot of polio, and we said, OK, to be on the safe side, to be prudent, we’ll give you a booster before you go,” Schaffner said. “It wasn’t really thought to be necessary, but it was a prudent, extra, easy, safe thing to do.”

Poliovirus lives in the intestinal tract and can be transmitted through stool, so wastewater surveillance is a logical way to track it, said Vincent Racaniello, a professor of microbiology and immunology at Columbia University in New York City.

More from this section

“These viruses have probably been in the sewage for years,” he said. “We’ve just never looked for them, and now we started to look because of this case. And I would say the more we look, we’re going to find it all over the U.S., especially in major cities.”

These strains of poliovirus likely entered the United States from people in other countries who have had the oral polio vaccine, Racaniello and Schaffner said.

The oral vaccine was the first developed and the easiest to administer, so it is still used as part of the World Health Organization‘s polio eradication efforts around the globe, the experts said. But, Racaniello said, it’s an infectious vaccine, meaning it contains a weakened version of the virus itself.

“It reproduces in your intestines, and you shed it — that’s the virus in the sewage,” he said. “That virus gets around very easily, and it can cause polio even though it’s a vaccine virus. After it passes through the human gut, it can reacquire the ability to cause polio.”

The United States stopped using the oral vaccine in 2000, after the U.S. Preventive Services Task Force decided that the risk of even a few incidental cases of polio was too great, Schaffner said.

“Each year we had about 4 million births and we had somewhere between six and 10 cases of vaccine-associated poliomyelitis,” he said. “We were giving a very small number of children and adults paralysis by using the oral vaccine.”

The U.S. now exclusively uses a four-dose inactivated polio vaccine.

“The virus is killed. There’s no possibility it can multiply. It cannot mutate. It cannot cause paralysis,” Schaffner said. “But as an inactivated viral vaccine, it has to be given by needle and syringe, which is more cumbersome and considerably more expensive and, of course, added to the number of inoculations little children were getting, which didn’t make moms too happy.”

Schaffner said it’s “notable” that vaccine-related poliovirus is circulating in the United States.

“We wouldn’t have expected it to be widely disseminated, so we’re just finding there’s even more intercontinental transmission of these oral polio vaccine viruses than we thought,” Schaffner said.

“If you had asked me before this case, I would have said that unless somebody has just gone abroad or had a visitor from abroad, you wouldn’t find it here because we’re not using [the oral vaccine] in the United States,” Schaffner added. “But we may be a smaller global community even than I thought.”

The only true protection is vaccination, and Racaniello hopes that wastewater surveillance data will help persuade the vaccine-hesitant to go ahead and get their jabs.

“Maybe they thought there was no poliovirus in the U.S., right? And so they say I don’t need to get vaccinated,” Racaniello said. “And so now we can show them that there is. In fact, I think we should do more surveillance of wastewater and show people, look, it’s in every major metropolitan city. You better get vaccinated.”

More information

The U.S. Centers for Disease Control and Prevention has more about polio.

SOURCES: Gail Shust, MD, pediatric infectious diseases specialist, NYU Langone Hassenfeld Children’s Hospital, New York City; William Schaffner, MD, medical director, National Foundation for Infectious Diseases, Bethesda, Md.; Vincent Racaniello, PhD, Higgins Professor, Department of Microbiology and Immunology, Columbia University, New York City

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Monkeypox outbreak 'shows signs of slowing' in Britain, health officials say – CBC News

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British health officials say the monkeypox outbreak across the country “shows signs of slowing,” but that it’s still too soon to know if the decline will be maintained.

In a statement on Monday, the Health Security Agency said authorities are reporting about 29 new monkeypox infections every day, compared to about 52 cases a day during the last week in June. In July, officials estimated the outbreak was doubling in size about every two weeks. To date, the U.K. has recorded more than 3,000 cases of monkeypox, with more than 70 per cent of cases in London.

The agency also said more than 27,000 people have been immunized with a vaccine designed against smallpox, a related disease.

“These thousands of vaccines, administered by the [National Health Service] to those at highest risk of exposure, should have a significant impact on the transmission of the virus,” the agency said.

It said the vast majority of cases were in men who are gay, bisexual or have sex with other men and that vaccines were being prioritized for them and for their closest contacts and health workers.

Last month, Britain downgraded its assessment of the monkeypox outbreak after seeing no signs of sustained monkeypox transmission beyond the sexual networks of men who have sex with men; 99 per cent of infections in the U.K. are in men.

British authorities said they bought 150,000 doses of vaccine made by Bavarian Nordic, the world’s only supplier. The first 50,000 doses have already been rolled out or will be shared soon with clinics across the country, and the next 100,000 vaccines are expected to be delivered in September.

WATCH | Canada records more than 1,000 monkeypox cases: 

Canada now has more than 1,000 monkeypox cases

5 days ago

Duration 2:02

As Canada hits more than 1,000 cases of Monkeypox, public health officials say we have enough vaccine supply. In the U.S., health officials are giving smaller doses of the monkeypox vaccine to stretch limited supplies.

Canada will use wastewater testing to track disease 

The Public Health Agency of Canada (PHAC) has repeatedly declined to provide the number of monkeypox vaccines Canada has in the national stockpile, citing security concerns, despite providing that number for other vaccines and other countries sharing that information.

Chief Public Health Officer Dr. Theresa Tam said during a news conference Friday that Canada has so far deployed 99,000 vaccines to provinces and territories. 

She said that it was “too soon to tell” if cases were slowing in Canada, although there may be “some early signs” that they are not increasing at the same rate as during the beginning of the outbreak.

There are now 1,059 monkeypox cases across Canada, with the bulk of them in Ontario and Quebec, and Tam said Canada will soon move to testing wastewater in different regions of the country to better track the spread of the disease, building off the infrastructure developed to monitor COVID-19 during the pandemic.

Anyone can become infected with monkeypox through multiple forms of close, physical contact with an infected person’s lesions, including skin-to-skin contact such as touching or sex, as well as through respiratory droplets in a conversation, or even being exposed to contaminated clothes or bedding. 

Most people recover without needing treatment, but the lesions can be extremely painful and more severe cases can result in complications including brain inflammation and death.

Globally, there have been more than 31,000 cases of monkeypox reported in nearly 90 countries. Last month, the World Health Organization declared the outbreak to be a global emergency and officials in the U.S. have classified the epidemic there as a national emergency, but Canada has not followed suit. 

Outside of Africa, 98 per cent of cases are in men who have sex with men. With only a limited global supply of vaccines, authorities are racing to stop monkeypox before it becomes entrenched as a new disease.

Tam said more than 99 per cent of monkeypox cases in Canada are in men and the median age of those infected is 35. Late last month, PHAC urged gay and bisexual men to practise safe sex and limit the number of sexual partners, in an effort to slow the spread of the virus among sexual networks.

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