Bird Flu in China Passed Person to Person, is Epidemic Possible? H7N9 Symptoms, Prevention & Treatment

Researchers in China have found strong scientific evidence of human-to-human transmission of a new form of bird flu, suggesting that the virus may be able to spread between people.

According to a study from the British Medical Journal (BMJ), Avian Influenza A (H7N9) was identified in China this year and as of June 30, 133 cases have been reported, resulting in 43 deaths.

The study points out that according to current available data, most affected patients have had a history of visiting live poultry markets or contact with poultry within a week of being diagnosed to the illness, showing that sources of infection are likely coming into contact with a contaminated environment or contaminated poultry.

However, recently a man was infected with the virus and was provided bedside care by his daughter who had no known contact with any poultry. Days after the father was admitted to the hospital, his daughter became ill and was also hospitalized. Both were diagnosed with the H7N9 virus and subsequently died from it.

Now, researchers on the team who published the BMJ study say it is vital to establish if the virus can transmit from person-to-person because of the potential of a pandemic if it possesses sustainable transmissibility between humans.

The study reports that the first patient, the father, regularly visited a poultry market and became ill about five days after his last exposure to poultry. He was hospitalized on March 9. As his symptoms worsened, he was transferred to ICU later on in the month, and then on May 4, died of multi-organ failure.

The second patient, the man's daughter, who had no known exposure to poultry, provided direct and unprotected bedside care for her father before he was admitted to ICU. Six days after her last contact with her father she became ill and was admitted to the hospital on March 24. She died on April 24 of multi-organ failure as a result of the H7N9 virus.

Two almost genetically identical virus strains were taken from the patients, suggesting the transmission of the virus was from father to daughter.

Forty-three other people who came in close contact with the patients were tested for influenza virus and all tested negative for H7N9.

The researchers concluded that the most likely explanation for this case is that the virus "transmitted directly from the [father] to his daughter."

They stress, however, that "the virus has not gained the ability to transmit itself sustained from person to person efficiently."

To the best of the researcher's knowledge, this is the first probable transmission of the virus from person-to-person and their findings reinforce that the virus does indeed possess the potential for a pandemic.

However, these findings do not imply that H7N9 has come any closer to adapting fully to humans.

According to James Rudge and Richard Coker from the London School of Hygiene and Tropical Medicine, limited transmission of the virus between humans is "not surprising, and does not necessarily indicate that the virus is on course to develop sustained transmission among humans."

Rudge and Coker say that while the study does not suggest that H7N9 is any closer to delivering the next pandemic, it does provide a timely reminder of the need to remain extremely vigilant and that the threat posed by the virus has by no means passed.

"It would be a worry if we start to see longer chains of transmission between people, when one person infects someone else, who in turn infects more people, and so on," Rudge said. "And particularly if each infected case goes on to infect, on average, more than one other person, this would be a strong warning that we might be in the early stages of an epidemic."

According to the Center for Disease Control (CDC), symptoms of news strain of bird flu include high fever and cough. Infected people often progress to more serious illnesses including severe pneumonia, acute respiratory distress syndrome, septic shock and multi-organ failure leading to death.

Preventative measures to avoid infection include avoiding domesticated birds, washing your hands and getting a flu shot. Since there is not currently a specific vaccine to prevent against H7N9, the CDC recommends antiviral drugs Tamiflu and Relenza to treat an infection.