QCOSTARICA – Will we ever be able to eradicate covid-19 from the world? Can it be removed from Costa Rican territory? Will SARS-CoV-2, the virus that causes this disease, persist among us? What awaits us?
There are no exact answers yet, but science already envisions possible scenarios given the characteristics of the pathogen and the disease. To draw a possible map of the future of this disease, La Nación spoke with specialists in Epidemiology, Public Health, Mathematics, Microbiology, Virology and vaccines.
They agree that vaccination has been a decisive tool that has changed the course of what we see today, but this does not mean that we can abandon our luck to inoculation campaigns.
“If at the end of this year, in December, we have a high percentage of people with second doses, 80% or more, that gives us the advantage of starting 2022 with a protective immunity level to maintain health services and that will allow to reactivate the economy, reactivate education, respond to waiting lists in health services, dedicate more to mental health,” said epidemiologist Ana Cecilia Morice Trejos, who was vice-minister of health and is an advisor to the Pan American Organization of Health (PAHO).
For the specialist in Biomathematics Tomás de Camino, who is director of the School of Intelligent Systems at Cenfotec University, massive events such as ColdPlay concerts in March, will increasingly be the norm.
“With a requirement for a vaccine and controlled use of a mask at an event, that already provides a fairly high level of security. In other countries, massive concerts are being held with protocols and there have been no reports of outbreaks. They are places with a high vaccinated population and the level of herd immunity is higher,” he affirmed.
Step by step: to understand what happens with the disease
To try to project a more long-term future on infectious diseases, it is important to know basic contexts in the framework of their impact on populations.
Eradication. For this to occur there cannot be circulation of the pathogen throughout the world. This has only been achieved with smallpox.
Elimination. The disease is eliminated from a country or region and no cases are detected. In Costa Rica, polio and measles have been eliminated, the elimination of malaria is on the way. There may be imported cases (such as that of the French who arrived with measles in our country in 2019), but these would not lead to a national outbreak, and if they do, it must disappear in less than a year. This status can be lost, the American continent eliminated measles, but outbreaks in several countries have appeared.
Endemic. The permanence of a disease in a country or region, but which is kept under control and whose cases are within those expected. Outbreaks can occur at different times, especially in susceptible populations, but it would not lead to an epidemic. In Costa Rica, there is endemic influenza and dengue fever, for example.
For the specialists consulted by La Nación, our country will enter the third scenario with covid-19. This will not begin just yet, because for now, the high circulation of the virus causes us to have an epidemic, but it will occur as more and more people with high levels of immunity (either by vaccination or natural infection) and the circulation of the virus is less.
“One would like to eradicate all infectious diseases, and that has only been possible for smallpox. There will always be susceptible people. We already know that this disease (covid-19) is here to stay,” said bioinformatics specialist microbiologist José Arturo Molina.
Morice adds that with smallpox there was also a special situation: at that time, the population density was much lower, the movements of people from country to country were less, and the virus was not as contagious as SARS-CoV-2.
Virologist Eugenia Corrales Aguilar adds that smallpox did not have an animal reservoir either, SARS-CoV-2, yes, whose reservoir is a bat and infections have also occurred in other animals.
Dr. Daniel Salas Peraza, Costa Rica’s Minister of Health, points out: “we cannot detach ourselves from the pandemic event at the global level. It is not a dengue or influenza epidemic that behaves very differently in tropical countries or elsewhere. With covid-19 it is more uniform and we are immersed in a global dynamic”.
Proof of this fact, Morice said, is the case of New Zealand, an island, with a small population and that has little migratory flow, where months ago it was said that the covid had been eliminated, but the cases reappeared. For the expert, it is clear that the disease cannot be eliminated due to the characteristics of the virus, so it is necessary to work on prevention to avoid outbreaks.
As he explained, respiratory diseases are more difficult to eradicate or eliminate because they are spread through the air. It does not require a vector, such as dengue or Zika, which requires a mosquito to be transmitted. In contrast, with covid, an infected person does not need more than a little of their saliva to transmit.
Looking ahead: sporadic outbreaks with close monitoring
In the longer term, when there is greater immunity and the circulation of the virus is less, there will be outbreaks, some larger than others, especially in more susceptible people, either because they are not immunized or because they have situations that weaken their defense system. This does not mean that it can affect and complicate the young and healthy as well.
“Covid-19 can transform into a disease that may have outbreaks from time to time, but that will never lead to saturation levels in hospitals and ICUs like the ones we saw last year and this year,” de Camino said.
Situations like this have been seen with previous pandemics, recalled the pediatric immunologist Olga Arguedas Arguedas, director of the National Children’s Hospital (HNN) in San Jose.
“It will be very similar to what happened with the Spanish flu or the bubonic plague and other great pandemics that preceded us. Yes, it is coming down, but even with that, there are going to be people who are going to die on the descent. We are also going to have sprouts, peaks, waves … so, we have to be very good surfers to navigate those waves and be victorious,” she said.
Molina agreed that it is to be expected that the number of cases will be increasingly reduced without saturating the health systems or forcing new restrictions, but personal measures will be necessary. It is also to be expected that the virus will become a “little bit less aggressive”, but even so, the risk for people who are not fully immunized is concerned, because the virus will find a niche in them who are susceptible.
“Viruses always find the susceptible, even if they are few, because it is their way of subsisting. They will find those who are not vaccinated, or those who have not developed a good immune response, or those who are much more exposed,” Morice confirmed.
Epidemiologist Juan José Romero also estimates that there will be pandemic waves of lesser magnitude in the world. The epidemic waves in Costa Rican will not be seen again the same size as the previous ones unless a new variant emerges for which the vaccines do not work, then we could have important epidemic waves.
Morice hopes that by 2023 we can have regained more normality, but this will happen little by little, it will not be overnight.
The most affected
Corrales indicated that reaching an endemic situation in the future does allow a respite for hospital services, but this does not mean that the virus ceases to be of concern and that complications and deaths will not occur; They will be to a much lesser extent, but we will continue to see them and our groups will be more affected than others.
“The famous living with the virus does not mean that it does not matter. Every year we are going to have people who are going to be infected, who are going to be hospitalized. There are going to be people who are going to die and who are going to die even if they have the vaccination. Vaccination is not a complete shield, but we are going to have much less impact. Will we get out of the pandemic with that? I don’t know, because it depends on the virus and the virus also depends on us,” said the virologist.
For the specialist, the behavior of the virus among the population will be like that of influenza, but with symptoms that can be more serious for the most vulnerable population. For this reason, she insisted, we cannot pretend to stop seeing hospitalized and dead every year, a situation that also occurs with influenza.
There are people who will suffer more from the impact of the endemic.
Romero points out that the numbers of important cases will first be seen in children under 12 years old, since they do not yet have a vaccine to protect them, but also in other populations, such as older adults and people whose immune systems do not work well.
Mortality would be concentrated mainly in these groups.
How to live with the virus?
Arguedas is emphatic that we must continue to take care of ourselves,” covid-19 is not going to disappear by magic and we have to learn to live with it intelligently.”
As Romero warned, the important outbreaks have to do with the behavior of the people and the freedoms granted by governments, factors that will be reflected in many cases of infection, in many cases of hospitalization, but with few deaths.
“What could happen in Costa Rica? A more or less similar scenario. With the elimination (of measures) we could have some peaks, with a low number of deaths compared to what was observed when there were no vaccines.
“You have to help with the vaccine. With the measures that we already know, we cannot say goodbye to the mask, open and ventilated places or handwashing,” he concluded.
The article was originally published in Spanish in La Nacion and translated and adapted by QCR staff.