Awaiting a vaccine

Manal Lotfy , Friday 1 May 2020

It is a waiting game for governments and populations around the world until a vaccine against the Covid-19 can be found, writes Manal Lotfy in London

Awaiting a vaccine

Governments around the world are desperate to deliver good news about easing the lockdowns imposed on economic and social activities to limit the spread of the Covid-19. But good news has become rare these days.

The World Health Organisation (WHO) said this week that there was “no evidence” that people who had developed antibodies after recovering from Covid-19 were protected against a second infection. Therefore, the idea of an “immunity passport” to allow people who have tested positive for antibodies to have fewer restrictions would be a very risky one, it said.

The “immunity passport” or “risk-free certificate” is one of the ways governments around the world are considering to ease some of the restrictions on populations to restart their economies. As a result, the WHO verdict is a major blow.

The assumption of immunity has not been proven, and thus easing restrictions on people who have been infected could increase virus transmission and lead to a second wave.

“People who assumed they were immune might stop taking precautions, which could actually increase virus transmission,” the WHO said.

“There is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection,” it said.

Most studies carried out so far have showed that people who have recovered from the coronavirus infection have antibodies in their blood, but some of these people have very low levels of antibodies, so the recurrence of infection may be possible.

“At this point in the pandemic, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an ‘immunity passport’ or ‘risk-free certificate,” the WHO said.

It said that laboratory tests to detect antibodies needed further validation to determine their accuracy and also needed to distinguish between previous infection by the SARS-CoV-2 virus, which causes Covid-19, and the six other known coronaviruses in circulation.

The assessment will only make it harder for countries around the world to lift some of the restriction on citizens based on the “immunity passport” concept.

Some governments have already considered permitting people who have recovered from Covid-19 to travel or return to work. Chile, for example, said it would begin issuing “health passports” to people deemed to have recuperated from the illness. Once screened for the presence of antibodies, they could rejoin the workforce, officials in Chile said this week. Many European countries including Germany, Italy and the UK are also beginning to test samples of their populations for antibodies.

While the WHO warning will make it difficult for many countries to ease restrictions on population movement, the antibody tests will continue in order to help to understand how the immune system reacts to the coronavirus.

In the UK, 25,000 people will be tested every month for the next year, both for antibodies and to check if they currently have the virus. This could provide more information about whether, and for how long, the disease confers immunity on those who have recovered. That would give a clearer idea about whether testing individuals and giving them some kind of immunity status might be an option in the future.

The WHO’s briefing came at the same time that UK Foreign Secretary Dominic Raab said that a coronavirus vaccine was “unlikely to come this year,” a U-turn after he said it was likely that a vaccine could be available later his year.

Developing a successful vaccine is one of the hardest tasks in medicine, and it is much harder than developing medications and drugs.  


TOWARDS A VACCINE: Vaccine development is often a long, highly regulated and complex process, usually lasting between 10 and 15 years and involving lengthy trials and big budgets, with no guarantee of success.

For example, the world has failed to develop a vaccine for the SARS virus despite its best efforts since 2003.

The idea of fast-tracking a new coronavirus vaccine has been met with doubts from scientists who believe in the traditional approach as a result. Only two of the 76 coronavirus vaccine candidates that the WHO follows closely have opted for the traditional scientific approach.

Traditional vaccines work by creating a weakened version of a virus, similar enough to the original that the immune system will be forearmed if a person is exposed to a full infection in future, helping to prevent actual illness.

Laboratory tests begin with small groups of individuals, and then tests extend to several thousand, then tens of thousands and finally hundreds of thousands of people.

According to the Philadelphia College of Physicians in the US, for a vaccine to be developed, tested and approved it must follow certain standard steps. The first stages are exploratory in nature. Then, there is regulation and oversight as the candidate vaccine makes its way through the process.

The exploratory stage involves basic laboratory research and often lasts from two to four years. Academic and government scientists identify natural or synthetic antigens that might help prevent or treat a disease.

The pre-clinical stage uses tissue-culture or cell-culture systems and animal testing to assess the safety of the candidate vaccine and its immunogenicity, or ability to provoke an immune response. These studies give researchers an idea of the cellular responses they might expect to see in humans.

They may also suggest a safe starting dose for the next phase of the research, as well as a safe method of administering the vaccine. The pre-clinical stages often last from one to two years and usually involve researchers in private industry.

An IND application then involves applying for Investigational New Drug (IND) status, where the labs and organisations involved describe the manufacturing and testing processes, summarise the laboratory reports, and describe the proposed study. An institutional review board, representing an institution where the clinical trial will be conducted, must approve the clinical protocol.

Once the IND application has been approved, the vaccine is subject to three phases of testing.

Phase I aims to assess the candidate vaccine in humans and involves a small group of adults. If the vaccine is intended for children, researchers will first test adults, and then gradually step down the age of the test subjects until they reach their target.

A promising phase I trial will progress to the next stage.

A larger group of several hundred individuals participates in phase II testing. Some of the individuals may belong to groups at risk of acquiring the disease. These trials are randomised and well controlled. The goals of phase II testing are to study the candidate vaccine’s safety, immunogenicity, proposed doses, schedule of immunisations and method of delivery.

Successful phase II candidate vaccines move on to larger trials involving thousands to tens of thousands of people. These phase III trials are randomised and double blind. After a successful phase III trial, the vaccine developer will submit a Biologics License Application to the medical regulatory authority, then this will inspect the factory where the vaccine will be made and approve its labelling.

With no prospect of a vaccine being developed soon and the doubt over the “immunity passports,” governments around the world have few options to end the lockdowns. No wonder many world leaders are preparing their populations to cope with the “new normal,” i.e. to continue living in “social bubbles”.

UK Prime Minster Boris Johnson, who returned this week to his office after recovering from coronavirus, is considering a blueprint to loosen the coronavirus lockdown that could allow Britons to choose 10 people they can mix with in “social bubbles”.

Scotland’s First Minister Nicola Sturgeon said she was considering expanding the definition of “households” to allow small gatherings of people. The possible changes come as England’s chief medical officer Chris Whitty said that some socially disruptive measures, including social-distancing, would have to be in place until the end of 2020. 

Meanwhile, the authorities in Belgium are also considering allowing residents to gather with 10 other people of their choice every weekend. New Zealand, one of the earliest adopters of the lockdown measures, has also settled on an expansion policy. From next week, New Zealanders will be free to slightly extend their bubbles of contact to include close family, caregivers and those living in isolation, so long as they are living in the same town or city.

The enlarged social bubbles may be an important coping mechanism for people around the world while the search for a vaccine continues. It is an unprecedented measure at an unprecedented time.

*A version of this article appears in print in the  30 April, 2020 edition of Al-Ahram Weekly under headline: United we stand

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