In the early hours of March 12, the World Health Organization (WHO) officially defined the new coronal outbreak as a “global pandemic”. By the time the news was announced, the outbreak had spread to 114 countries around the world, resulting in more than 110,000 infections and 4,291 deaths, and the number of cases and deaths is expected to rise further. This is the first pandemic caused by a coronavirus.
What are the criteria for judging a “global pandemic”?
Previously, the WHO had adjusted the risk level of the new crown outbreak to “high” and then to “very high”. So under what circumstances would the WHO assume that a disease has entered the global pandemic?
There are no clear criteria for determining whether a disease is entering a “global pandemic”.
“Global pandemic” was originally used by the WHO to describe the stage of an influenza outbreak, but now, according to WHO’s definition, refers to “a global outbreak of a new disease”. At present, there is no clear criterion for determining whether a disease is entering a global pandemic, but the medical community recognizes that “pandemic” includes three criteria:
1, the virus in the population has pathogenicity and lethality, that is, the virus caused by the disease is more harmful;
2, the virus can continue to spread from person to person;
3. There is evidence of a global epidemic of the disease.
It can be seen that the “global pandemic” refers not only to highly contagious, but also to highly pathogenic and fatal. Therefore, once the disease into the “global pandemic” stage, will cause great harm around the world.
Assessments of the infectiousness of a disease are usually expressed in R0, i.e. how many people a patient can infect without intervention. In R0-lt;1, the disease is not contagious, and when R0-1, the disease will spread limitedly and become a local epidemic. Once the R0 value is greater than 1, the number of infections will rise exponentially, resulting in large-scale infection. At present, the R0 value of the new coronary pneumonia is estimated between 2-3, indicating that it is highly contagious.
WHO Director-General Dr Tandeser said the term “global pandemic” was used with great caution and that, based on the extent and severity of the current outbreak, WHO believed that COVID-19 was already characterized by a pandemic. But WHO also says a pandemic does not mean that humans are powerless to deal with disease. Calling the outbreak a pandemic “does not change WHO’s assessment of the virus threat, does not change what WHO is doing, nor does it change what countries should be doing.” “
Those “pandemic disease” events in history
The history of mankind is also a history of the struggle against infectious diseases. There has been no shortage of infectious disease pandemics in history.
Since the 20th century, influenza has caused several pandemics, most recently the H1N1 flu in 2009. According to the U.S. Centers for Disease Control and Prevention (CDC), the first case of infection was detected in April of that year, with the U.S. outbreak peaking from May to June, and on June 11, the WHO declared the flu a global pandemic. It was not until December 2009, when the vaccine against H1N1 was put on the market, that the outbreak was brought under control, and in August 2010, the WHO declared the outbreak over.
Also causing the pandemic was the 1918 Spanish flu. From January 1918 to December 1919, the flu swept the world, experienced three bands of morbidity, and in the deadly second wave of outbreaks, the number of deaths and infections from influenza dropped rapidly, the researchers speculated, because of the common phenomenon in the flu outbreak: the most deadly strain has died with the death of the host. The remaining strains are not infectious and lethal. Still, the flu pandemic killed about 50 million people worldwide.
In addition to these diseases, the infectious diseases that have caused the global pandemic include cholera, AIDS and the infamous Black Death. Fortunately, humans have eliminated the Black Death, and improved sanitation has led to a gradual decline in cholera. Even AIDS, once considered incurable, can be used by drugs to keep the virus at very low levels, ensuring the life span and quality of life of patients.
In recent years, we can hear from time to time the outbreak of an infectious disease in a certain place, the outbreak of SARS (Severe Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome), influenza A and other infectious diseases are still fresh in memory. It seems that the pandemic disease has become more and more, but in fact, SARS is not defined as a pandemic because it is quickly brought under control. Influenza A(H1N1) has been briefly defined as a pandemic, but because of its low fatality rate, the threat to people is relatively small, and some have criticized the definition as inaccurate.
Throughout history, the disease may experience several peaks of infection before the number of people infected declines. Thanks to medical developments, people can use vaccines and drugs to control diseases without passively waiting for the virus itself to weaken.
Watch out for help and tackle the global epidemic
New coronary pneumonia is affecting the whole world. In the face of the outbreak, the response varies from country to country. Many countries, including Denmark and France, have taken measures such as school closures, bans on large gatherings and restrictions on tourists, and Italy, which is mired in the outbreak, has decided to block the entire country. At the same time, there are some countries still uphold the “Buddhist” attitude, has not yet taken effective measures to curb the further spread of the epidemic.
WHO Director-General Dr Tandeser called on countries to take “urgent and drastic action”. He said that at present, countries can take strong measures to effectively inhibit and control the spread of the virus. By detecting, detecting, treating, isolating, tracking, and mobilizing the participation of the national population in response measures, a small number of cases in the country can be prevented from developing into clustercases, or clustercases from developing into community transmission. Even countries and regions that have seen cluster edified cases and community transmission can reverse the trend through treatment, isolation and tracing.
As with any disease pandemic in the past, the fight against disease has become a common battle for all mankind. No matter which country or industry you are in, you have to be involved in this battle. Understanding the dangers and ways of spreading the disease, gathering less and washing hands frequently, can not only protect themselves and their families, but also do their part to stop the spread of the epidemic.