On August 22, a U.S. citizen was admitted to the hospital with “unusual symptoms.” Subsequent sampling by the Centers for Disease Control and Prevention (CDC) confirmed that the patient had been infected with the H5N1 virus. Thus, 14 cases of bird flu have been recorded in the United States this year. The difference is that in the latter, there was no direct link with infected animals.
The patient could have infected, in addition to a member of his family, a health worker who had treated him. Although new information from the CDC increased that number to seven workers, increasing the chances of Contagion of bird flu between humans. “The simple answer is that we still don’t know,” he tells EL ESPAÑOL. Ursula Höfleveterinarian and researcher at the Hunting Resources Research Institute (IREC-CSIC).
It is true that none of the seven cases have yet been confirmed, but if that were the case (since all have developed symptoms), the virus would be we are getting closer to the “pandemic”as some American experts have already warned. It would then not be an “isolated case”, as state authorities defined it during a press conference held two weeks ago.
The next day, the CDC revealed that two workers who had been in contact with the patient had developed symptoms. “As no tests were carried out, we do not know whether they had bird flu or a cold,” explains Höfle. The problem is made worse because the CDC cannot send members of this organization to the state unless the state requests it (a request that the Missouri Department of Health and Senior Services has not not formulated at the moment).
This institution has also received criticism over the way the situation was handled. “The credibility of health care is at stake. [estadounidense]”, Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told trade media. Statistical. He also expressed concern about the time it takes to find out who may have been infected and in what way.
Difficulty identifying cases
The contagion of confirmed patients also worries virologists because he has no known contact with livestock or birds. However, in the state of Missouri, no infected herds have been reported, as has happened in other parts of the country: 239 herds in 14 states have tested positive for H5N1, although it is suspected that this number could be higher. Until now, transmission of the virus had only been confirmed among people working on farms housing infected animals.
But this new affair opens the door to a mutation of the virus and can be transmitted more easily between humans. And when a new infection occurs, the virus has the “opportunity” to acquire new mutations and evolve into a form that could lead to a possible pandemic.
“That’s the big question,” Höfle says of the origin of the contagion. “There is a first jump, which goes from animals to humans. And then there is the one which occurs between humans. The latter can be effective and be the first step towards massive contagion or simply cause a local epidemic.
The researcher remembers that in 2005 “there was a lot of fear” because the highly pathogenic strain of bird flu also caused contagion between people. Although there were “isolated cases”, The lethality of the virus in humans was close to 60%. “A new mutation does not cause a pandemic, but the virus can carry a pandemic risk. It must therefore be monitored very closely.”
Among the workers who were in contact, one of them tested negative in the test carried out. But it cannot be ruled out that it was carried out too late to detect the infection. To the three who subsequently showed symptoms, no tests have been carried out for now. Missouri health officials said they are analyzing antibody test results, which could reveal whether they have been exposed to the virus.
“What cannot be traced with certainty is whether the source of exposure is the already confirmed patient,” explains Höfle. For its part, the CDC is analyzing a blood sample from the confirmed case and a family member. To the latter No tests were performed to confirm the infection.despite the fact that he fell ill the same day the other contact was hospitalized.
One of the excluded hypotheses is that the other seven cases developed a common flu, because it is not the season. Its arrival, expected at the beginning of autumn, could affect avian flu, making it difficult to identify H5N1 cases.
