The U.S. Centers for Disease Control and Prevention (CDC) said it is tracking a number of red flags that indicate that bird flu could be the next global pandemic. This was written by Newsweek, reported by UNN.
The first severe human case of avian influenza in the United States was reported in Louisiana earlier this month. Genetic analysis has shown that the virus has mutated, making it more easily transmissible to humans, the Centers for Disease Control and Prevention said.
The agency called the mutations “disturbing” and “a reminder that A(H5N1) viruses can undergo changes during the clinical course of human infection.
On Monday, the CDC told Newsweek that while the risk of avian influenza to the public remains low, the agency is closely monitoring several “red flags” that could indicate the virus could be on the verge of a pandemic.
These include any outbreaks of avian influenza transmitted from person to person, as well as evidence that the virus has mutated, making it easier to spread between people.
“The discovery of epidemiologically linked clusters of human cases of A(H5N1) influenza may indicate that the virus has begun to spread better between people,” a spokesperson for the CDC's Avian Influenza A(H5N1) team told Newsweek.
Increasing cases of human infection with avian influenza from animals may also indicate that the virus is “adapting to spread more easily from animals to humans,” they added.
“The CDC is looking for genetic changes in circulating viruses that indicate they may be better transmitted between people,” said a spokesperson for the Center.
The CDC has warned that any of these factors could “increase the CDC's risk assessment for the public.
However, in none of the cases in the United States are there any signs of human-to-human transmission. All of them occurred in isolation, after contact with infected animals.
“Until now, such mutations have been detected infrequently and have occurred in the context of prolonged infection in individual patients, not at the time of initial contact with the influenza A(H5N1) virus circulating among animals,” said the Center's representative.
The CDC says that since 1997 it has been actively tracking thousands of reports of human cases of avian influenza worldwide, recording them and watching for warning signs that avian influenza is becoming more and more transmissible.
The spokesperson added that the CDC is also working with numerous state partners to look for evidence “indicating the spread of influenza A(H5N1) from person to person.
The recent case in Louisiana falls into the category of “red flags,” the spokesman said.
However, according to the CDC, this case would have raised more concerns if the mutations had been detected in birds or at an earlier stage of infection, when the patient was more likely to have unknowingly spread the virus.
Although the Louisiana case is the first severe case in the United States, more than 60 mild human cases have been reported in the United States this year.
Experts say that the increase in the number of cases is caused by a sharp rise in the incidence of bird flu in wildlife populations, which, in turn, “puts more people at risk.
About 65 cases of avian influenza were reported in 10 states: California, Colorado, Iowa, Louisiana, Michigan, Missouri, Oregon, Texas, Washington and Wisconsin.
A state of emergency has been declared in California, where 37 cases have been reported.
The latest report from the CDC on December 24 states that 10,917 birds in 51 jurisdictions have been found to have the infection.
The vast majority of human cases of avian influenza occur as a result of contact with infected animals. Typically, wild birds transmit the virus to domestic animals, including poultry and livestock. Humans then become infected by contact with an infected animal, its feces or saliva.