Recent outbreaks of avian influenza and measles have highlighted the need for greater awareness and understanding of these highly infectious diseases. Although COVID-19 has demonstrated an unprecedented capacity for global transmission, the global impact of avian influenza and measles is not expected to be as severe due to differences in modes of transmission and the availability of preventive measures.

COVID-19: COVID-19, caused by the SARS-CoV-2 virus, has resulted in a global pandemic, affecting millions of people worldwide. The symptoms of this disease are varied and include fever, cough, shortness of breath, fatigue, muscle aches, sore throat and loss of taste or smell. It is spread mainly through respiratory droplets from infected people coughing, sneezing, talking or breathing.

Bird Flu: Bird flu, or avian influenza, is caused by several subtypes of the influenza A virus. The symptoms of bird flu vary, but often include fever, cough, sore throat, shortness of breath, muscle aches and fatigue. In severe cases, complications such as pneumonia and respiratory failure may occur. Transmission of bird flu primarily occurs through contact with infected birds, their droppings or contaminated surfaces. Human-to-human transmission is rare but has been observed in certain cases.

Measles: Measles, caused by the measles morbillivirus, is a highly contagious viral infection.  Typical symptoms of measles include a high fever, cough, runny nose, red and watery eyes, and a typical rash that usually starts on the face and spreads throughout the body. Transmission of measles occurs through respiratory droplets when an infected person coughs or sneezes. The virus can remain contagious in the air and on surfaces for several hours, increasing the risk of transmission in crowded places.

Changes in global impact: COVID-19 has a unique ability to spread rapidly around the globe, causing significant illness and death. Its high rate of transmission, coupled with a lack of immunity in the population, has led to its widespread global spread. In contrast, the global impact of avian influenza and measles is not the same. Avian influenza primarily affects birds, with limited human-to-human transmission, and there are effective vaccines and surveillance systems in place to manage outbreaks. Measles, although highly transmissible, is largely preventable through vaccination, which has greatly reduced its global incidence.