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MOSCOW, May 15. /TASS/: Most of coronavirus patients have blood type A, while those having blood type AB are the fewest, chief of Russia’s Federal Medical Biological Agency Veronika Skvortsova said on Friday.
"An interesting fact that was noted by foreign specialists and has been verified by the Agency’s centers. The overwhelming majority of those infected have blood type A," she said at an online news conference organized by TASS. "Next are types O and B. And, indeed, the rarest is type AB."
She noted however that it might be because type A is the most widespread among the population.
One half of coronavirus patients in Russia have no symptoms, the proportion of asymptomatic cases in Moscow is about 60%, Veronika Skvortsova noted. "The proportion of asymptomatic cases is very high: in Moscow it accounts for 60% and in the country in general — almost one half, every second case," she said.
As for patients who experience mild symptoms of COVID-19 caused by the novel coronavirus, they can lack the necessary number of antibodies to form immunity to the disease, Skvortsova noted. "It has been widely documented that people who recover from mild forms [of COVID-19] do not have enough antibodies in the concentrations needed to obtain real immunity."
Skvortsova stressed that the number of patients with severe forms of the disease was not growing. "Fortunately, the number of cases that require additional oxygen and artificial lung ventilation is declining as well," she noted.
COVID-19 incidence in Russia has stabilized by now, the official went on. "By now, the situation with the newly confirmed coronavirus cases is relatively stable as the daily growth has been around 10,500 recently," she stated.
"However the recent month demonstrated that we already had such a period before the May Day holidays and if the number of people who, say, go out frequently, were as it had been a month ago, we would have seen the epidemic’s regression," she said.
Incubation period
The average incubation period for the novel coronavirus is about five days, Veronika Skvortsova said. "On average, the incubation period is about five days, five or five and a half days, not one or two days, as is the case with other acute respiratory infections."
It is still unclear for how long a recovered patient remains a carrier of the novel coronavirus, Veronika Skvortsova continued.
"It should be acknowledged that it still remains unclear for how long the virus stays in the human body. Scientists in different countries are now trying to find out. If the presence of the virus in the nose or throat is not identified, that does not mean that the virus is absent from the patient’s body altogether," Skvortsova said. According to descriptions of several cases in different countries, some recovered patients who twice tested negative for coronavirus developed the disease again after exposure to cold or excessive strain.
"This may happen for two reasons — either repeated infection or reactivation of the virus still present in the human body," Skvortsova elaborated.
Earlier, the chief physician of the republican infection hospital in Buryatia, Tatyana Symbelova, told the media that a female patient had to be taken to the hospital again with COVID-19.
In late December 2019, Chinese officials notified the World Health Organization (WHO) about the outbreak of a previously unknown pneumonia in the city of Wuhan, in central China. Since then, cases of the novel coronavirus — named COVID-19 by the WHO — have been reported in every corner of the globe, including Russia.
On March 11, 2020, the WHO declared the coronavirus outbreak a pandemic. According to the latest statistics, over 4,543,000 people have been infected worldwide and more than 303,000 deaths have been reported. In addition, so far, over 1,712,000 individuals have recovered from the illness across the globe.
To date, a total of 262,843 coronavirus cases have been confirmed in Russia, with 58,226 patients having recovered from the virus. Russia’s latest data indicates 2,418 fatalities nationwide. Earlier, the Russian government set up an Internet hotline to keep the public updated on the coronavirus situation.