Alarm to spread bird flu from cats to humans

The first case in New York City was discovered and reported to be infected with a rare, avian flu virus that can spread directly from cats to humans.

According to the New York City Department of Health, this is the first case reported to be infected with the H7N2 virus (a variant of avian influenza virus) due to exposure from an infected cat. While the risk of direct infection like this is extremely low, officials still warn that cat owners should pay attention to pet health issues in order to take appropriate precautions.

"Whenever the virus adapts to a new animal, the risk of transmission will increase. Therefore, we are very worried about the health of the cats in the area as well as their owners," Ivars Varma - Deputy director of disease control at the New York City Department of Health said.

The virus has spread at least to about 45 cats in an animal protection center in Manhattan. The reason is that infected cats have spread to veterinarians. The doctor accidentally infects most of the remaining cats when treating them.

Avian influenza virus has spread to cats and from there to humans.(Image source: Shutterstock).

Last week, more than 100 cats tested positive for H7N2 viruses throughout animal protection centers in New York City. Although the virus is not yet easily transmitted from cats to humans, it has already developed the ability to spread easily from cats to cats.

This is not only the first time that H7N2 virus has been transmitted from cats to humans, but it is also the first time this virus has the ability to pass from poultry to cats.

But the good news is that this strain of influenza virus is just an extra variant, not too dangerous . The sick veterinarian only experiences some mild flu symptoms and then fully recovered in a short time.

Of the 350 people tested because they were exposed to cats in Manhattan protection centers, only one case was confirmed to be infected.

The Department of Health said the risk will be highest when people are exposed to respiratory secretions of infected cats for long periods of time.

In infected cats, if they are too old and weak, the virus will attack aggressively and fatally. But in young and healthy cats, they will be easy to overcome and recover completely.

Between 1996 and 2012, most people infected with the H7 influenza virus (H7N2, H7N3 and H7N7) reported in the Netherlands, Italy, Canada, the United States, Mexico and the United Kingdom are all involved in poultry. The infection mainly leads to symptoms of pinkeye and mild upper respiratory inflammation, with the exception of 1 death in the Netherlands. So far no cases of H7 influenza virus infection have been reported in China.

Type A influenza viruses are divided into variants based on two surface proteins, hemagglutinin (HA) and neuraminidase (NA). For example, "H7N2 virus" is a type of influenza A virus that has one HA of 7 proteins and one NA 2 protein. Similarly, the "H5N1" virus has one HA of 5 proteins and one NA 1 protein.

There are 17 HA variants and 10 NA variants. Various combinations of HA and NA may occur. All variants of influenza A virus can infect birds, except for the H17N10 variant found only in bats. Only two variants of influenza A (H1N1 and H3N2) are circulating in humans. Several variants are found in other infected animals, for example H7N7 and H3N8 cause horse disease and H3N8 cause dog disease.