Costa Rica purchased three million units of the Pfizer and BioNTech vaccine against COVID-19, which now shows encouraging progress in its preliminary results. In early October, the country announced the agreement with the companies and indicated that the drug would be enough to immunize 1.5 million people since two doses are needed to be applied for each patient.
Costa Rica would receive at least three million doses of this vaccine in the course of 2021. The government asked the company to deliver the doses “progressively” during the year. The Ministry of Finance; estimated that vaccinating the entire population would cost between ¢ 24,000 million and ¢ 45,000 million.
Delivery logistics, meanwhile, would be another challenge. Still, Pfizer told in early October that they do not expect any mishap with the delivery of the vaccines. “Innovative packaging and storage mechanisms have been developed for the candidate vaccine against COVID-19,” the company said through its press office.
“These packages contain GPS sensors, which will indicate the location and temperature of each shipment, in order to anticipate any deviation or problem, to act and solve before something happens,” they added.
In addition to this acquisition, the country also made a purchase through the COVAX mechanism of the World Health Organization (WHO). In this way, Costa Rica would receive vaccines for one million people. In total, vaccines are insured for 2.5 million people in 2021.
The Minister of Health, Daniel Salas, estimated that he hopes to begin vaccination in the first half of 2021. The first groups to receive the vaccine would be the elderly, health personnel and people with risk factors.
What do the results say?
A preliminary analysis by Pfizer and BioNTech showed an encouraging result: it was 90% effective in preventing COVID-19 among patients who had not been previously infected. The company started phase 3 of clinical trials in July. Some patients received the real vaccine and others received a placebo. The tests look at whether people who got the vaccine get less sick. Among the nearly 44,000 participants, only 94 people fell ill with COVID-19. Preliminary analysis suggests 90% effectiveness in preventing COVID-19; that is, few vaccinated people became ill.
The US Food and Drug Administration (FDA) calls for a vaccine that is at least 50% effective. If these results hold, the vaccine would be approved. But details are still missing. The company did not publish its results in a scientific article, but only sent out a press release. Because of this, the data cannot be reviewed yet.
The Pfizer vaccine uses a system called “messenger RNA.” If approved, it would be the first commercial vaccine of its kind to hit the international market. Vaccines work by training the body to recognize and attack pathogens, in this case, the SARS-CoV-2 Coronavirus.
Traditionally, a “deactivated” version of the virus is introduced into the body so that the body can recognize it. Sinovac (China) uses this method in its Coronavirus vaccine. But in 1990, scientists at the University of Wisconsin discovered that they could “trick” the body into producing the proteins of a virus without inserting that virus, using the RNA molecule.
The Pfizer and BioNTech vaccine use this method to train the body. Its application, like most of the possible vaccines against COVID-19 understudy, is with two doses. Patients receive a first, and three weeks later they receive a second. Protection would be achieved seven days after the last dose. In total, reaching protection would take 28 days.
So far, the results seem to indicate that the vaccine is safe. Pfizer noted in an investor presentation that the side effects are mild headache and some fatigue.