Bird Flu Spreading Rapidly in Kathmandu, Affecting Poultry and Raising Health Concerns

Bird flu is currently being observed in dozens of places in Kathmandu. Farmers have suffered significant financial losses, and concerns and interests are also being expressed regarding human health. 

Various studies and research have shown that migratory birds play a role in spreading the bird flu virus from one place to another. Just a few months ago, it was confirmed that dozens of crows in Kathmandu died due to bird flu. 

The Department of Animal Services has stated that the main reason for thousands of birds being infected is infected crows. Infected crows with bird flu are referred to as 'crow flu' in this article.

• What is Bird Flu?

Flu viruses are of four types: 'A', 'B', 'C', and 'D'. Among these, flu 'A' and 'B' viruses particularly affect human health. Flu 'A' has a history of taking the form of a pandemic at various times in the past. 

Under flu 'A' fall seasonal flu like 'H3N2' (also colloquially called 'Hong Kong Flu'), 'H1N1pdm09' (also colloquially called Swine Flu), and various species of bird flu. 'H3N2' and 'H1N1pdm09' tend to be more active twice a year, specifically in February-March and July-August. 

Among the various species of bird flu, 'H5N1' and 'H9N2' viruses are currently considered the main causative viruses infecting chickens in Nepal. Human casualties due to the 'H5N1' bird flu virus first occurred in Hong Kong in 1997. Similarly, the 'H9N2' bird flu virus was first confirmed in humans in Hong Kong in 1998. 

'H5N1' bird flu virus is classified as a highly pathogenic avian influenza, while 'H9N2' bird flu virus is classified as a low pathogenic avian influenza. The mortality rate of the 'H5N1' bird flu virus has been observed to be over 50 percent. 

However, the data shows that only a few individuals have died due to 'H9N2', meaning its symptoms appear normal in most people. Nevertheless, in Nepal, 'H9N2' bird flu is currently causing deaths in large numbers of farmed birds (chickens). 

What symptoms appear in humans if infected with bird flu?

Specifically, 'H5N1' and 'H9N2' viruses have been confirmed in birds in Nepal. If infected with the 'H5N1' bird flu virus, severe symptoms can appear in humans. High fever, cough, sore throat, runny or stuffy nose, body and head aches, and in some cases, diarrhea can occur. 

Breathing difficulties and severe pneumonia are its main complications. Recently, it has been confirmed in America that this virus has also spread to humans through cattle or infected cow's milk. Red eyes have appeared as the main symptom in such infections. 

However, it is said that fever is not very common in bird flu transmitted in this way. There is a big difference in symptoms when bird flu spreads from chickens and cattle or milk. Will the symptoms of 'H5N1' virus-infected 'crow flu' in humans be different from these two sources? It would not be wrong to say that this is currently a subject of discussion. 

The other 'H9N2' bird flu virus currently spreading appears to be limited to mild symptoms based on past observations. So far, only 2-4 infected individuals have been confirmed to have died worldwide due to this virus, while about 200 people have been confirmed infected. Cough, sore throat, runny nose, fatigue, muscle and joint pain, and mild fever are the main and initial symptoms that appear after infection. 

In cases confirmed with bird flu, treatment can be done using the antiviral drug 'Oseltamivir'. However, a vaccine against bird flu has not yet been developed or made available for humans. 

In conclusion, the Department of Animal Services has concluded that the bird flu virus has spread to chickens and ducks through infected crows. And, as this article is being written, the bird flu virus still appears to be spreading at lightning speed in Kathmandu. Dozens of poultry farms are being affected due to bird flu. 

Some public awareness information is available about ways to avoid infected chickens with bird flu. However, there is still less discussion, minimal information, and in some cases, confusion about how people should take precautions from 'crow flu', i.e., infected crows roaming around our homes. 

Since crows are birds that fly in the open sky, it seems almost beyond imagination for humans to control them. In other words, 'crow flu' appears to have a high probability of continued spread. Nevertheless, to prevent 'crow flu' from gaining further momentum, the concerned bodies need to provide or develop simple and practical measures for the citizens. This is because bird flu has occurred in the past, and there is no room for complacency that it will not appear in the coming years. 

Dr. Pun is the coordinator of the Clinical Research Unit at Shukraraj Tropical and Infectious Disease Hospital.