IMG's Chief Medical Officer Discusses The COVID-19 Vaccines & Their Impact on The Future of Travel

IMG's Chief Medical Officer, Dr Geoff Tothill MB, BS, FRCP Edin. FFTM RCPS Glas. Cert AvMed. shares his expertise on the COVID-19 vaccines and their impact on the future of travel as of early February 2021.

Q: Historically, the COVID-19 vaccines have been the fastest developed vaccines on record. How were we able to do this safely?

A: Firstly, vaccinologists have recognised for some time that we need a faster process for producing vaccines to protect against new viral threats as they emerge. Various teams have been developing the technologies required to manufacture RNA vaccines with the flexibility to rapidly repurpose a vaccine for emerging new variants. At the time of the Pandemic, a range of companies were using mRNA in immunotherapy for cancer, so there was already a great deal of safety information and experience in their use. Secondly, we know a lot about coronaviruses. We’ve experienced coronavirus pandemics before, and both SARS and MERS were extensively studied. There were candidate vaccines for both of those pandemics, so we had a flying start when it came to developing vaccines for COVID-19 because we knew that targeting the ‘spike protein’ was likely to be important. Additionally, the resources that have been mobilized around the globe to produce a vaccine have been enormous. And finally, the speed that we can recruit people to studies and then report on the results has really improved in the last couple of years. All of these things, together, have helped us to produce effective and safe vaccines very quickly.

Q: If someone has already recovered from COVID-19, should they still get the vaccine?

A: Yes - they should still get vaccinated. The reason is that the natural immunity you get from having the virus is probably weaker than the immunity that will be derived from getting the vaccine. Based on the research, thus far, there doesn’t seem to be any reason, clinically, why you shouldn’t get the vaccine. If anything, it is expected to boost your immune system and give you protection longer than already having had COVID-19.

Q: There are quite a few vaccines available, is there a "best" option and should people receive more than one?

A: In general, there is not a "best" or "ideal" vaccine as any vaccine currently being administered has gone through the necessary research to be approved for use. In terms of receiving more than one, the best practice is that you will get the booster dose of the original manufacturer and same delivery mechanism as the first one you received. We don't have enough data on the effects of mixing and matching vaccines and boosters. For example, if you get the AstraZeneca vaccine, you should get the AstraZeneca booster. This could change in time, but we just don’t have enough information at the moment to know if giving a different vaccine as a booster dose would be effective or safe.

Q: Do you think that passengers will be required to present documentation prior to being allowed to travel?

A: Many months ago, we speculated that one thing that could unlock international travel would be a vaccination certificate, but there are difficulties with that from an administrative standpoint. There needs to be a universally accepted mechanism for recording everyone’s vaccination status; there has to be a common certification that is recognized across the globe, which would give countries confidence that their inbound travelers have actually been vaccinated. This is already in place for yellow fever vaccination, with some countries requiring travelers to have a valid vaccination certificate before entering, but I suspect it will be some time for nations to agree on protocols, requirements, and documentation.

Q: Why do you think that we're seeing a variance from country to country in terms of quarantine and travel requirements. Do you think we will have a more consistent process for individuals arriving into a country with regard to quarantine and testing?

A: I'd love to see a single approach for quarantine and testing, but I think we will continue to see a divergence of approach as individual countries respond with local policies based on the trends of their own case numbers and possibly in response to the emergence of a new variant virus, which they will seek to keep out of their countries. We are beginning to understand how we will use testing in the travel industry and I think we will start to see countries requiring negative rapid and PCR tests as a requirement for entry. One problem with rapid tests is that they are often completed outside of a clinical environment. This is convenient for the traveler, as these can be done by individuals in virtually any location, even airports. However, it means they are less authoritative than PCR testing done in a lab. I believe this is why we are seeing a lag in countries accepting rapid antigen testing for inbound travelers. There are several keys to finding an accurate and reliable test for the purposes of travel. Additionally, we must determine if the false positive and negative rates of a particular test are acceptable. Individual countries are concerned that the tests have been properly performed and not just for the traveler’s convenience.

Q: How much of an incidence of COVID-19 in a population needs to be present to determine the vaccine effectiveness?

A: At a study level, we have data from about 20,000 people on the Pfizer trial, 15,000 on the Moderna trial, and around 20,000 on the AstraZeneca trial. From a regulatory standpoint, those are ample numbers to know that the vaccines are effective. I would expect that within a few months of starting vaccination programs, we will be able to get an indication of the effectiveness in a real world situation. I don’t expect it to be vastly different from the efficacy rate in the trials, which would be roughly 80-90%. These studies will not have identified everybody that came in contact with the virus nor everyone who contracted it, which makes it difficult to determine the effectiveness unless you have huge testing capacity, but given the current data, we can be confident that the current vaccines provide a great deal of protection from the serious disease that can be caused by the currently circulating virus.