The Seychelles is the most vaccinated nation on Earth. But Covid-19 has surged

The Seychelles is causing concern for world health experts after a rise of Covid-19 cases among fully vaccinated individuals.

The World Health Organization said Tuesday that it would review coronavirus data from the Seychelles, an archipelago of 115 islands in the Indian Ocean, after the health ministry said more than a third of people who tested positive for Covid-19 in the week to May 8 had been fully vaccinated.

The Seychelles is viewed as having conducted a very successful vaccination rollout so far; it can boast having the highest share of people vaccinated against Covid-19 anywhere in the world, above Israel and the U.K.

The majority of vaccinated people have received China’s Sinopharm vaccine (approved for emergency use by the WHO last Friday) as well as the AstraZeneca shot (known as Covishield locally, a version produced in India). In total, the Seychelles with a population of over 97,000 has recorded just under 8,200 cases and 28 deaths during the pandemic.

On Monday, the Seychelles’ health ministry reported a steep rise in the number of cases. From 120 new cases reported on April 30, a week later over 300 cases per day were recorded on May 7 and May 8, respectively.

Of all the positive cases, the health ministry said 63% had either not been vaccinated or had only received one dose of SinoPharm or Covishield, but 37% of the new infections were in people who had received both doses.

The ministry noted that, of the patients requiring hospital treatment, 80% had not been vaccinated and tended to be people with co-morbidities. It added that “almost all” of the critical and severe cases requiring intensive care treatment had not been vaccinated either. To date, none of the patients who have died with Covid-19 have been fully vaccinated, it said.

To date, among those who a have received two doses, 57% have received Sinopharm and 43% Covishield, the Seychelles’ health ministry said.  It’s unclear which vaccine had been given to individuals who had been fully immunized but then tested positive for Covid.

While there was a flattening of new cases on May 7 and May 8 (with 317 new cases reported and then 314 cases, respectively), the health ministry said “the rate of transmission remains high and is of concern.”

The situation has certainly alarmed experts, particularly as 60% of the Seychelles’ total population has been fully vaccinated. What’s more, 86% of the Seychelles’ targeted population for vaccination — 70,000 people — have been fully vaccinated to date, ministry data shows.

On Monday, WHO’s Director of Immunization, Vaccines and Biologicals, Dr. Kate O’Brien, said in a briefing that the WHO was in direct communication with the Seychelles’ health ministry and that the situation was a “more complicated situation than the top-line messages.”

“As was noted, the vaccines are highly efficacious against severe cases and deaths. Most of the cases which have occurred are mild cases. However, what is also important is that a substantial fraction, over 80% of the population, has been vaccinated. But as we know … some of the cases that are being reported are occurring either soon after a single dose, or soon after a second dose, or between the first and second doses.”

She said in this specific situation, a very detailed assessment was required “of what the situation is, first of all what the strains are that are circulating in the country, secondly when the cases occur relative to when somebody received doses, third what the severity of the cases is.”

“Only by doing that kind of evaluation can we make an assessment of whether or not these are vaccine failures or whether it is more about the kinds of cases that are occurring, the milder end of cases and then the timing of the cases relative to when individuals received doses. That evaluation is ongoing and we’re supporting and engaging with the country to understand the situation.”

CNBC has contacted the WHO for updated comment on the situation in the Seychelles but is yet to receive a reply.

The WHO has repeatedly warned that vaccination alone would not be enough to stop the pandemic in its tracks, but would rather be another weapon in the arsenal to fight the virus.

Restrictions on social contact as well as good personal hygiene are still seen as the basis of preventing the spread. Last week, the Seychelles re-imposed restrictions on some social gatherings and public spaces in a bid to curb the rise in infections.

The situation faced by islanders acts as a reminder that no coronavirus vaccine currently in use has been proven to be 100% effective at preventing Covid-19 infection. Still, all the vaccines currently authorized for use by the WHO have proven to be very, if not extremely, effective at preventing serious Covid infections, with cases, hospitalizations and deaths greatly reduced in countries with advanced vaccination programs, like the U.K.

With a third wave of cases and new virus variants having the potential to cause further loss of life and economic destruction, time is of the essence to approve and distribute life-saving vaccines around the world, with the more available, the better.

On Friday, the WHO granted emergency use authorization to the China’s state-owned pharmaceutical firm SinoPharm, a move which could fast-track the shot’s use in WHO’s COVAX scheme, which aims to provide poorer countries with access to vaccines.

The WHO said the addition of the SinoPharm vaccine had “the potential to rapidly accelerate Covid-19 vaccine access for countries seeking to protect health workers and populations at risk.”

It noted that the WHO’s Strategic Advisory Group of Experts on Immunization had completed a review of the vaccine and, on the basis of all available evidence, recommended it for adults 18 years and older, in a two-dose schedule with a spacing of three to four weeks.

“Vaccine efficacy for symptomatic and hospitalized disease was estimated to be 79%, all age groups combined,” it said. However it noted that “few older adults (over 60 years) were enrolled in clinical trials, so efficacy could not be estimated in this age group.”

In March, AstraZeneca released updated clinical trial date which showed its vaccine was 76% effective at preventing against symptomatic Covid-19 infection. Vaccines by Pfizer–BioNTech and Moderna were found to be around 95% effective.