After coronavirus broke out in Wuhan, China, in December 2019, within a few months, the new virus had spread to almost all continents across the world. And when on January 30, following the recommendations of the World Health Organisation (WHO) Covid-19 was declared a Public Health Emergency of International Concern (PHEIC), the world was plunged into a desperate search for a vaccine against the virus.

So far, the virus has infected more than 11.9 million and killed more than 545,000 people worldwide.

World scientists then agreed to speed up research on a vaccine to help contain the spread of the epidemic and facilitate care for those affected. But a vaccine is yet to be found.

It is encouraging that the global community has mobilised resources around vaccine work for COVID-19 and scientists are working on potential treatments and vaccines, but a cure is yet to be found.

A vaccine trains the immune system to recognise and attack the virus when it encounters it. A vaccine, therefore, stimulates the body to raise an immune response before you get infected with a pathogen so that your body recognises infection with the pathogen when it enters your body and neutralises it. As a result of the vaccine, you either become immune to the disease or suffer fewer consequences of it.

Vaccines protect both the person who is vaccinated and the community. Viruses cannot infect people who are vaccinated. As such, people who are vaccinated cannot pass the virus to others, which is known as herd immunity. Not only would a vaccine save lives, but it would also protect people against the disease.

For instance, Kenya would not have lost 143 lives nor 8,250 persons infected with the virus by July 7, 2020, if a vaccine was available. Besides, a vaccine would also obviate the social distancing restrictions most of us are now living under and ease the ongoing ‘economic lockdown’. In addition, vaccines would help protect health workers and slow down the negative effects of Covid-19.

Currently, all efforts are trained in developing a vaccine. WHO has listed more than 140 different vaccine candidates, currently in various stages of the pre-clinical trial.

The initiatives on new vaccine candidates against COVID-19 are led by leading scientists from the academic sector, large private pharmaceutical companies and small biotech companies. Many companies are working on antiviral drugs, some of which are already in use against other illnesses, to treat people who already have COVID-19. Other companies are working on vaccines that could be used as a preventive measure against the disease.

It could take several months before treatments known to work effectively against COVID-19 are available. It could be even longer for a vaccine. Some of the earliest treatments will likely be drugs already approved for other conditions or have been tested on other viruses.

Ideally, it takes long to develop a vaccine. After laboratory and animal testing, drugs have to pass through several clinical trial stages before they can be approved for widespread use in people.

Trials are organised in phases, with Phase I and Phase II trials typically testing the safety of a drug. Then the drug enters Phase III trials, where its efficacy is tested. All these phases can take between 10 and 20 years. Regulatory review and approval processes take another two years or so.

Due to the rigorous process involved, less than 10 percent of experimental vaccines ever become commercial products. It is also difficult to speed things up, because scientists have to enroll enough people in each stage to have useful results. They also have to wait long enough to see whether there are harmful side effects of the drug.

Developing a vaccine is also a costly enterprise, costing between 200 and 500 million dollars to develop. For all these reasons, we need not lower our guard yet. With no drug insight, we still have to rely on social distancing, contact tracing, self-isolation, and keenly following other measures outlined by the Ministry of Health. No study exists to show that there are particular people or groups of people immune to the virus. Indeed what has been shown is that people of all ages, gender and race can get the virus. For this reason, we need to be vigilant, more than ever before, because we are all equally susceptible to the virus.

-The writer is CEO at the Kenya Medical Training College (KMTC)