WHO has declared the Public Health Emergency of International Concern (PHEIC) a total of 7 announcements. In each announcement, there were the following reasons:
1. 2009, H1N1 influenza
-Serious? Yes (highly transmission, CFR 0.02%, vaccine unavailable at that time)
-Unusual/Unexpected? Yes (new emerging pathogen)
-International spread? Yes
-Trade/travel restriction? Yes
2. 2014, Polio
-Serious? Yes (CFR 2-5% among children/ CFR 15-30% among adolescents and adults)
-Unusual/Unexpected? No
-International spread? Yes (WHO aims to eradicate for preventing a global resurgence of the disease)
-Trade/travel restriction? NO
3. 2014, Ebola in Western Africa
-Serious? Yes (CFR 40-50%)
-Unusual/Unexpected? Yes (re-emerging pathogen)
-International spread? Yes
-Trade/travel restriction? Yes (WHO does not recommend general bans on travel or trade, or general quarantine of travelers arriving from Ebola-affected countries. However, 30 countries have instituted restrictions on travel from the three West African countries most affected by Ebola)
4. 2015, Zika virus
-Serious? Yes (4-6% of pregnant people infected with the Zika virus have children with microencephaly )
-Unusual/Unexpected? Yes (new emerging disease)
-International spread? Yes (vector-borne disease)
-Trade/travel restriction? NO (If you are pregnant, you should NOT travel to areas with Zika outbreaks.)
5. 2018, Ebola epidemic in Kivu region
-Serious? Yes (CFR 67%)
-Unusual/Unexpected? Yes (re-emerging pathogen)
-International spread? Yes
-Trade/travel restriction? Yes
6. 2019, COVID-19
-Serious? Maybe Yes (CFR 3% [2017], available vaccine but limited)
-Unusual/Unexpected? Yes (new emerging pathogen)
-International spread? Yes (zoonotic and human-to-human transmission)
-Trade/travel restriction? Yes
7. 2022, Monkeypox
-Serious? No (IFR 1.4%, highly spreading)
-Unusual/Unexpected? Yes (re-emerging pathogen)
-International spread? Yes
-Trade/travel restriction? No
In the future, I really hope that the war between Ukraine and Russia will not use dirty bombs or nuclear weapons. However, if it would be used, it will cause public health emergency of international concern because radioactive substances not only cause serious disease, they can spread far into the air and contaminate water that can reach neighboring countries or go beyond that.
Feel free to correct me, If I’m wrong.