RIO DE JANEIRO, BRAZIL – The Butantan Institute director Doctor Dimas Covas said that vaccination against the novel coronavirus could become periodic. The assessment does not only refer to the CoronaVac, which the institute produces.
“I do not know if annual, but periodic vaccination will be required, should the virus remain,” said the researcher of the Brazilian Institute which will produce the CoronaVac in partnership with Chinese Sinovac. The interval and amount of doses of the CoronaVac are still under study.
According to the doctor, who was interviewed on Saturday in an education network, the novel coronavirus (Sars-CoV-2) should continue to circulate, as it already occurs with other types of coronaviruses, but in a “very little pathogenic” way, that is, less harmful, after the population is vaccinated.
“I think it [the virus] will remain,” said Covas. “It’s really speculation, for a very simple reason: we have coronaviruses circulating. It’s not the first time we’ve found a coronavirus. Now, in winter, many people will suffer a type of cold caused by a coronavirus”, said the researcher, recalling that there are three types of coronaviruses.
As a reference, the vaccination campaign against influenza conducted by SUS (National Health System) is annual and aimed specifically at priority groups, such as the elderly, people with chronic diseases and health professionals, but anyone may be vaccinated.
“A person catches a cold by this coronavirus, develops immunity against it. Some time goes by, this immunity drops and next year the person catches this coronavirus again”, explained Covas. “This may happen [with the novel coronavirus]. Hence the need for periodic vaccination. If this occurs, it will need to be included in the vaccination calendar [of the Ministry of Health]”.
Interval between doses is still uncertain
There is still a debate over the interval between the two CoronaVac doses. In the state immunization schedule submitted by the São Paulo government, it will be 21 days between one shot and the other. However, during the last press conference, an interval of between 15 and 28 days was speculated.
Covas said that this needs to be improved, because it is a very recent vaccine, with the goal of reaching a single dose.
“These vaccines are still in their initial development stages. They are still newborns, they are a few months old”, reflected the researcher. “There will still be room for technological growth, for development, improvement until, up front, we have an excellent quality vaccine, with a dose once every ten years, which is the dream of everyone who works with vaccines”.
Calendar not yet defined
The Ministry of Health has signed an agreement with the Butantan Institute for exclusive distribution of the CoronaVac, a vaccine against Covid-19 produced in partnership with the Chinese Sinovac. As a result, all 10.8 million doses that were in possession of the São Paulo government since December will be passed on to the federal government.
The question remains as to how vaccination will be performed in São Paulo. The João Doria government is maintaining the schedule for January 25th, but has failed to explain how this will be the case if the federal government is late – given that the vaccines are now in the federal government’s possession.
For its part, the government has not yet set a date, given that the CoronaVac has not yet been approved by ANVISA (National Health Regulatory Agency), but it is also considering January.
The application for the vaccine’s emergency use, previously scheduled for December, was only submitted by Butantan last Friday, January 8th, and on Saturday, January 9th, ANVISA released a statement asking the Butantan for documents that had been expected, but failed to be delivered.
In reaction, the Butantan stated that “it continues providing all the required documents” and that “the deadline established to authorize the use of the vaccine” will not be affected. ANVISA did not comment on this.
Should the deadline be maintained, the agency has until January 18th (ten days since the documents were submitted) to issue an opinion on the application.
So far, the calendar in São Paulo is as follows:
1st phase of Covid-19 Vaccination in São Paulo
Target audience 1st dose* 2nd dose*
Healthcare workers, indigenous and quilombolas communities:
January 25th – February 15th
75 years of age or older:
February 8th – March 1st
70 to 74 years of age:
February 15th- March 8th
65 to 69 years of age:
February 22nd – March 15th
60 to 64 years of age:
March 1st – March 22nd